List of Units

Wednesday, November 21, 2018

UNIT 9 - NEWER TRENDS IN FOOD SERVICE INDUSTRY IN RELEVANCE TO NUTRITION AND HEALTH

NEED FOR SERVING NUTRITIONAL AND HEALTH- SPECIFIC MEALS

Food provided by residential institutions, such as boarding schools, college hostels, hospitals and old- age homes, are probably the one source of nutrition for the residents and must be adequate. The list of residential institute is long, and it is the responsibility and moral obligation of the caterer to provide nutritionally adequate meal to the resident. Sample menu based on the principles of meal planning and recommend dietary allowances (RDAs) should be provided to the caterer to ensure that the meal is balanced as well as attractive, appetizing, & affordable. Correct cooking practices should be followed to prevent looses of heat – liable nutrients, oxidative losses as well as leaching losses. While selecting commodities, fruits and vegetables at proper stage of maturity, which are fresh and intact, should be purchased. If convenience foods are to be purchased, their cost should be considered. The foods standards laid down by the govt. of various commodities should be checked especially for compulsory standard. For example the fruit product order for processed fruit and vegetable products such as tomato sauce, pineapple slices in syrup etc. just planning balanced meal is not sufficient. The nutrients present in the food should be conserved while preparing food, and cooking practices which enhances nutrients should be observed.
  Eating out has become a way of life. In the past, people eat in restaurant to celebrate a special occasion or it was a weary traveler on the look out of bed and board. Today, practically everybody who steps out of the house for work, education, or business has at least one main meal away from home. Number of food joints to shoot every strata of society has mushroomed in towns and cities. Many of these places are unlicensed, with the food handler having little or no knowledge about nutrients and nutrition, health and diseases. The purpose of eating is to satisfy the hunger pangs & tickle the taste buds. What the consumer looks for today is cost and convenience, the majority paying little heed to the oil bubbling and frothing in the fry pan , or to the non-discriminated addition of ajinomoto to make vegetarian food more flavorful. To make quick money, hygienic practices are ignored or sufficient investments in proper storage and cooking equipments is not made leading to the vicious cycle of diseases and malnutrition affecting work efficiency and productivity.
Some common practices which reduce the nutritional value of food are harmful to health are:
Buying poor quality fruits and vegetables in bulk because of lower rate.
Improper storage leading to further loss of nutrition.
Faulty cooking practices such as using excess water and then evaporating it to get correct constituency: cutting and then washing vegetables.
Overcooking and discarding cooking water( for liquor)
Soaking vegetables in water
Cooking in an open pan
Keeping hot food over extended service period.
Repeated reheating of entire food of instead of reheating quantity required.
Adding alkali to hasten softening of pulses and vegetables and to preserve green colour.
Using Aji-no-moto(MSG) in all preparations to bring out the flavor of food aji-no-moto is used in soups in place of stock permitted level in food is 1%

NUTRITIVE VALUE OF FAST FOOD AND JUNK FOOD

The fast food industry is growing rapidly all over the world to provide a quick meal to the customer at an unaffordable cost and in very little time. in India the fast food industry comprises mainly of south Indian, Punjabi snacks and popular MNCs like KFC, MC’D, pizza hut etc. many product have been modified to suit the Indian palate and respect religious sentiments. Many of these provide take away or drive-thru services as well as sitting area to eat food on the premises. Modern commercial fast food is often highly processed & prepared & industrial fashion. Most items on the menu are prepared at central supply facility & then shipped to individual outlets where they are reheated / cooked or assembled in a short time. The central kitchen ensures consistency in product quality & ability to deliver the order quickly to the customer eliminating labour & equipment cost in the individual restaurant.

NUTRITIONAL EVALUATION OF NEWLY LAUNCHED PRODUCTS

A wide variety of convenience foods are available and new products and attractive packages are being launched every day to meet growing demands of working women, single families, the elderly and commercial establishment who are too busy to invest valuable time and labour in pre-preparation. The newly launched products in the market can be categorized under 5 heads namely:
Basic product – needs some preparation before cooking e.g. shelled green peas
Ready to cook products – needs no further preparation before cooking e.g. frozen green peas
Ready to use products – must be prepared and heated e.g. instant tomato soup powder
Pre cooked products – prepared dish which needs heating before consumption e.g. paneer makhanvala
Table ready products – packet can be opened and eaten e.g. potato chips
Many products launched in the market make health claims which at times could be misleading. Convenience is not the main criteria, but meeting the days nutritional needs should be checked. Some newly launched products based on soya proteins Are industrial prepare often under strict regulation and control and sometimes bacteriology safer than fresh goods, if they are not stored under temperature controlled storage during retailing, their nutritive value and overall quality can be grossly affected.
Many products launched in the market make health claims which at times could be misleading. Convenience is not the main criteria, but meting the days’ nutritional needs should be checked. Some newly launched products based on soy proteins, flax seeds, carotene and vitamin E rich oils have distinct benefits while other foods such as non-diary creams have both advantages because of no cholesterol and disadvantages
Because of fatty acids composition of vegetables, oils seeds. Bakeries shortenings in the market are especially designed for a particular product and the ready product are of superior quality but the Trans fatty acid present in these fats are harmful to health.


ANTIOXIDANTS

They are compounds that prevent oxidation. Oxidation is the process that turns newspaper yellow and cut apples brown. Oxidation leads to degenerative changes in our body. Antioxidants such as vitamin C, Vitamin E, beta-carotene and selenium help protect against free radical damage. They scavenge free radicals and protect body cells against cancer. They prevent atherosclerosis and coronary artery diseases (CAD). The sources of antioxidants are listed below:
Vitamin E soya oil, sunflower oil., almond, spinach, and mint
Vitamin C amla, guava, green leafy vegetables and all citrus fruit
Beta-carotene all green leafy vegetables, and all yellow orange and read fruits and vegetables.
Selenium whole grain, pulses, green leafy vegetables and cauliflower
Non- nutrient antioxidant phenolic compounds, favonoids and isoflavones present in beans, cloves oats, tea, coffee etc.
We need to consume much more than the RDA for antioxidant effect.

SIGNIFICANCE OF NUTRITIONAL LABELING

Nutrition facts labels tell you about the nutrition of a particular product. This information includes serving size, number of servings in the package, calories per serving and the amount of various nutrients contained in the product. Once you understand the labels, they can help you follow a healthy diet and make it easier to choose the most nutritious foods.

Making Healthy Food Decisions -Nutrition labels do affect people's food choices. When you are deciding between two different foods, you can look at the nutrition labels to determine which food is more nutritious. You can compare the labels to determine which foods are lowest in calories, fat, saturated fat, trans fat, cholesterol, sodium and sugar. These are the ingredients you should limit for good health. Checking the ingredients list will help you avoid foods that contain additives or other ingredients that you want to avoid. The foods with the fewest ingredients and those that only contain ingredients that you would have in your own kitchen are healthier than those with lots of ingredients you don't recognize.


Maintaining a Healthy Weight - Reading nutrition labels can help you make the right food choices when you are trying to lose weight or prevent weight gain. In a study published in the "Journal of the American Dietetic Association" in April 2000, people told by their doctors to lose weight for health reasons who used nutrition labels consumed fewer calories, more fiber and less saturated fat, sugar and carbohydrates than the people who didn't use nutrition labels.


Nutrient Consumption - Many Americans don't consume enough fiber, iron, calcium, and vitamins A and C, so these are always included on nutrition labels. You can use the percent daily values listed on the label to give you a good idea which foods are high or low in these essential nutrients. Foods that contain at least 10 percent of the daily value for a nutrient are good sources of that nutrient, and foods that contain 20 percent of the daily value for a nutrient are considered high in that nutrient.


Considerations - While nutrition facts labels can be helpful, not everyone understands the information included or the importance of it. A study published in the "American Journal of Preventive Medicine" in November 2006 found that people who had low levels of literacy and numeracy often didn't understand these labels and that even some people who were more literate sometimes had trouble interpreting nutrition facts labels. Doctors and other health providers need to provide education to their patients on how to use these labels when making dietary recommendations.



PREBIOTIC AND PROBIOTIC FOOD

Probiotics – These are “good” bacteria that help keep your digestive system healthy by controlling growth of harmful bacteria.

 Prebiotics - These are carbohydrates that cannot be digested by the human body. They are food for probiotics.
The primary benefit of probiotics and prebiotics appears to be helping you maintain a healthy digestive system.

Good Sources Of Probiotics - One of the best sources of probiotics is yogurt. It has good bacteria like lactobacillus or bifidobacteria. Look for “live or active cultures” on the label to be sure your favorite brand of yogurt is a rich source of probiotics. Other good food sources are sauerkraut, miso soup, fermented, soft cheeses (like Gouda), and even sourdough bread. The common feature of all these foods is fermentation, a process that produces probiotics.

Good Sources Of Prebiotics - To help maintain healthy level of prebiotics, you can feed them with the foods you eat. Foods rich in prebiotics include asparagus, Jerusalem artichokes, bananas, oatmeal, and legumes.

NUTRACEUTICALS

Nutraceutical, the words “nutrition” and “pharmaceutical”, is a food or food product that provides health and medical benefits, including the prevention and treatment of disease.
"A nutraceutical is a product isolated or purified from foods that is generally sold in medicinal forms not usually associated with food. A nutraceutical is demonstrated to have a physiological benefit or provide protection against chronic disease."
Such products may range from isolated nutrients, dietary supplements and specific diets to genetically engineered foods, herbal products, and processed foods such as cereals, soups, and beverages.


CRITICAL EVALUATION OF FAST FOODS

  • Fast food is refers to those kinds of food that are prepared and ready to be eaten within the shortest time possible.
  •  Additionally, fast food constitute foodstuffs that are available for sale in restaurants and stores made up of ingredients that that can be preheated or precooked without any problem and served in a take away form . 
  • Fast foods are characterized by high fat content, high calories, high cholesterol, and quick, convenient and high sodium concentration. 
  • Similarly, it is inexpensive made from ingredients that are cheap such as fat meat and refined grains. These kinds of foods are not only available in restaurants but also in vending equipment as well as 24-hour expediency stores.
  • Examples of fast food include the following, sandwiches, hot dogs, pitas, fried chicken, French fries, chicken nuggets, tacos, pizza, hamburgers, fish and chips and ice cream to mention but a few.

MERITS OF FAST FOOD

Saves time

The most notable argument brought forth in support of fast food is that it saves time as well as convenience. On the same note fast food save time in the context that one will not engage in all those activities of buying, cleaning such food stuffs, cooking as well as washing dishes. It is also true that when one gets home after a tiresome day thus very tired and bored, the efforts needed to cook can be substituted with having fast food.

Saves money

Similarly, fast foods are cheaper. This is because they are made from cheaper ingredients such as refined grains, meat with a lot of fat among others instead of ingredients that are expensive and nutritious such as vegetables, lean meat and fresh fruits. On the same note considering people who live alone, the expenses of cooking are much higher compared to when buying fast food.

Health advantage

Despite the fact that those opposing fast food claim that it results to various problems in human health, it is worth noting that fast foods have contributed to taller and individuals with higher life expectancy.

Sharing and convenience

It is evident that fast food are usually packed in away that it can be taken out of the restaurant and eaten from anywhere, be it in the car, office, at the bus station. Additionally, unlike other kinds of food, fast food comes with the absolute advantage of splitting and sharing between or even amongst individuals.

Reliability

A study carried out asking why individuals bought fast food established that reliability of such kind of food is what propels them to buying them. Fast foods are easy to obtain, are in plenty, varied in nature and readily available.

Nutritional information

Most of the fast food joints have adopted a culture of making available the information concerning nutrients of their food. It is worth mentioning that with such kind of information as well as a number food stuff variety, one has a chance to choose the best kind of food that suits him or her.

DEMERITS OF FAST FOOD

Health issues

It has been brought forth that fast foods are characterized by high fat content, high calories, high cholesterol, and quick, high sodium concentration and made from ingredients that are cheap such as fat meat and refined grains. All these pose a greater risk to human health.  Too much eating of fast food with such health problems as obesity, high blood pressure, cardiovascular disorders, and liver problems.

Heart attack

Fast foods are prepared using Trans fat which is an artery-clogging fat. Food prepared using this fat includes French fries as well as chicken nuggets to mention but a few.

Increased high blood pressure

Fast food contains a good deal of sodium concentration, this aggravates the risk of high blood pressure.

Obesity

 Continual eating of such kind of food means that we accumulate a lot of calories in our body that are not useful leading to individuals being obese.

Liver problem

Since the liver is responsible for purification/filtering of harmful substances as well as producing substances that help breakdown fats, when fast foods are consumed every now and then, the liver will be overloaded and damaged. This in turn leads to very serious health problems that can be fatal.

Addiction

It has been documented that fast food is addictive. What this means is that individuals who are used to eating such foods cannot go for long without having a bit of such food.

Family bond

The issue of fast food has been brought forth as another factor that jeopardizes family bond. This is because no or very minimal time is used in preparing food together, leave alone eating together. Young people are spending more of their time in having a meal with their fellow friends other than their family members.
Psychologist hold that meal time is a family meeting where each and every member is in a position to share their thought, ideas, problems as well as feelings. This usually helps in strengthening the bond between and among family members. This is in jeopardy during this era of growth in fast food industries.

Lower nutritional content

Fast food has been linked and it is a fact that most of them apart from pizza lack dietary fiber as well as essential micro-nutrients such as vitamin and minerals. It is worth mentioning that food that lack fiber brings with it a number of stomach complication such as constipation.

Expensive

Although previously it was stated that fast food is inexpensive, that was only true when considering an individual buying such kind of food cooking at home. It is important to not that a family visiting or buying fast food once in a while is not that expensive, but when this is done more often, then the amount of money spent can be quite much more as compared to if the family could just buy the food in super market, take the time to prepared it and enjoy a dinner or lunch together as a family

CONCLUSION


We should not advocate for doing away with fast food due to its various disadvantages,but that we should not fight the industry and bring it down to its knees but rather champion for further improvement of fast food that will bring out high quality and healthy food. This will indeed ensure that people consume healthy foods and at the same time cushioning those that depend on the industry for their daily bread from economic uncertainty of doing way with the sector.


UNIT 8 - MASS FOOD PRODUCTION

Definition


  • Mass production is the manufacture of large quantities of standardized products, frequently using assembly line or automation technology. 
  • Mass production refers to the production of a large number of similar products efficiently.

Various methods of cooking


BOILING

This is done by immersing food in boiling water maintain the temperature at 100-degree Celsius till food is cooked in the water. Water is boiled due to conduction and convection of heat. Foods that are usually cooked by boiling are rice, potato, pasta, sage, etc. Boiling is one of the simplest methods of cooking and widely used all over the world.

POINTS TO TAKE INTO CONSIDERATION WHILE BOILING FOOD


  • Water which has to be used for boiling should be just sufficient since a large quantity would leach all the nutrients
  • Boil the vegetables with their skin, or cut them into big pieces which prevent them from nutrient loss.
  • Use the boiled water as stock in soups and making curries so that the nutrient lost in the water can be conserved
  • Boiling food vigorously consumes a lot of fuel and makes the food mushy, soft and spoils its texture.
  • EXAMPLES
  • Carotene present in carrot is lost when boiled in an open vessel.

SIMMERING

Food is immersed in water and cooked in a covered pan at 98-degree Celsius. This method is used for the food that takes long to cook like meat, fish. Especially used for fishes as they don’t disintegrate easily while cooking.

POINTS TO CONSIDER WHILE SIMMERING FOOD


  • Should not rush otherwise the food may break down and may turn mushy.
  • It is a time and fuel consuming method.
  • While simmering, heat sensitive nutrients are lost.

POACHING

Poaching is done by cooking the food item with a small amount of water at 80-85 degree Celsius. Foods which are generally poached are eggs, fruits and sometimes, even certain types of fishes.

POINTS TO CONSIDER WHILE POACHING

Water-soluble nutrients are lost, so one should try and use that water in making gravies or soups.

STEWING

Stewing is done in a covered pan with a small quantity of liquid and once the liquid reaches the boiling point the flame is set to sim mode which makes it a slow and long process. Fruits and vegetables can be cooked by this method and no nutrient loss is observed as 1-2 tablespoon liquid is left which is served along the food but this process is highly time and fuel consuming.

BLANCHING

Food is blanched by immersing the food items in hot water and then cooling them under cold water. Usually, food items that need to be frozen, for example, peas are blanched.
This process helps in preserving the natural colour of the vegetables and fruits and to reduce the microbial load on the food.

STEAMING

Steam generates heat, this heat is used as a medium to cook and so it takes a longer time as compared to boiling. It’s of 2 types:

  • Wet-steaming: Food is cooked by being in direct contact with the steam. For example, while cooking idlis, dhokla, dumplings this method is used.
  • Dry-steaming: Food is cooked by using steam to provide heat to a utensil in which food is being cooked, without any direct contact of food with the steam. For example, double boiling in the case of chocolate.

Steaming is better than boiling as it cooks food faster and steaming helps in preserving the nutrients, colour and flavour in food as there is no nutrient loss due to contact with water.

PRESSURE COOKING


  • Food is cooked under pressure. With an increase in pressure, the temperature, also increases. Thus, the food is cooked very fast. Actually, it is a type of steaming in which water is boiled under high pressure, thus raising the temperature and reducing the cooking time. The equipment used for this purpose is a pressure cooker.Foods which can be cooked in a pressure cooker easily are pulses, rice, vegetables and meat.
  • Water soluble nutrients are lost in pressure cooking the food so one should use the water in making gravies.

FATS AS MEDIUM OF COOKING

In this method of cooking, fats are used as a medium to prepare food.

FRYING

Done at 180-220 degree celsius using oil or fat as the medium to cook. Food is cooked at a fast pace. The types of frying are:

SHALLOW FRYING

In this method, the oil submerges only half of the food product and then food is browned. one has to be careful not to burn the food because the food is cooked at a fast pace. For example, Parantha (Indian bread) is made this way.

DEEP FRYING

In this, the food item is completely immersed into hot oil in a large quantity. Foods cooked using this method are pakoras, samosas, French fries, etc.

POINTS TO TAKE CARE WHILE FRYING


  • Overheating and re-heating of oil for a long time can decompose it. When oil begins to smoke, chemical breakdown of oil begins and Acrolein and free fatty acids are formed from Glycerol. If this happens repeatedly, then the Acrolein formed causes irritation in eyes and nostrils. This breakdown is known as pyrolysis. So prolonged frying should be avoided. It may form aldehydes and other by-products that are harmful to the health and may cause cancer. Oil that has been used once shouldn’t be used again for the same reason mentioned above.
  • Use only MUFA rich oil for cooking
  • Also, never mix the used oil with fresh oil.


BRAISING

It is a combination of using moist and dry heat to cook. This method helps in retaining the moisture or JUICE WITHIN THE FOOD PRESENT. For example, while making Vermicelli Kheer, Vermicelli is first roasted and then cooked in simmering milk.

DRY HEAT AND AIR AS MEDIUM OF COOKING

GRILLING AND BROILING

Food is cooked by placing the food either above, below or in between a hot surface like burning wood, charcoal or any other heating element. Here food is cooked by radiation.

POINTS TO TAKE INTO CONSIDERATION DURING THIS PROCESS


  • Charring may occur.
  • Temperature used for cooking is high so negligence may result in burned food.


BAKING

The food is kept in the center of an oven and the food is cooked by radiation. It makes the food brown, crisp and soft inside. The temperature at which food is usually prepared is 120-250 degree celsius. Used to make cakes, cookies, vegetables, poached eggs, sweet dishes, etc.
This process consumes a lot of electricity. Other than electric ovens, conventional oven method or microwave ovens are also used.

MICROWAVE OVEN

It works on the principle of electromagnetic waves which are produced by power source magnetron and are absorbed by the food.
It is the best method for retaining the antioxidant activity in garlic and mushrooms
About 20-30% of vitamin c in green vegetables is lost during microwaving, which is less than most cooking methods as less water is used.
On the whole, it is the best method as nutrient retention is the most in this method.
Even enhancement of flavour and uniform cooking is seen in less time.

HOW TO REDUCE NUTRIENT LOSS WHILE COOKING


  • Don’t throw the water used to soak the dal and rice as it can be used to cook food again
  • Never use soda to hasten the cooking of pulses as it destroys the nutrients present in them especially vitamin B.
  • Boil the vegetables with peel so that nutrients are not lost.
  • One can also use the vegetables and fruits with peel to cook as they have the most of the nutrients present in them.
  • Always cook the green leafy vegetables in an open lid for initial five minutes as it helps to retain colour
  • Always cut the vegetables and fruits in bigger pieces as in smaller pieces, greater the total surface area of the food exposed therefore is greater and so is the loss of nutrients due to leaching and oxidation.
  • Do not fry and overheat the oil as Acrolein would be formed and can cause harmful diseases like cancer.
  • When peeling the skin of vegetables do peel as thinly as possible.
  • The nutrients in vegetables and fruits are concentrated just below the skin, so peeling before boiling increases the loss of Vitamin C, Folic Acid and other B vitamins. The peels of carrot, radish, gourd and ginger can be scraped instead of peeling. Peel only when absolutely necessary.
  • Do not cut vegetables into very small cubes as each small part comes in contact with oxygen, destroying vitamins.
  • Do not soak vegetables in water to prevent discoloration. Almost 40 %  of the water soluble vitamins and minerals are lost in the soaking water. If you must soak, use up the soaking water to knead dough, prepare soups and gravies.                                                  
  • Root vegetables should be boiled with skins on and then peeled after boiling. This helps the nutrients to migrate to the center of the vegetables, helping better retention of its nutrients. Do eat with skin on whenever possible.
  • Certain amount of minerals and vitamins are lost even during preliminary washing before cooking. Washing may remove as much as 40% of the thiamine. That’s why it is preferable to wash rice with minimum amount of water.
  • Salads should be prepared just before serving and should be served in closed dishes to avoid excessive exposure to air.
  • Do not throw away the excess water drained after boiling rice or vegetables. When preparing cottage cheese, the water left over after curdling is called whey. It is extremely rich in good quality proteins and vitamins and should be used up in preparing gravies, kneading dough or simply had as a refreshing drink after flavoring with lemon juice and salt and pepper.                 
  • Do not keep milk open or exposed to light, as considerable destruction of riboflavin can occur.
  • Baking soda makes cooking water alkaline and thus helps retain the color of vegetables as well as speed up the cooking process, BUT  it destroys thiamin and vitamin C.
  • Cooked vegetables when exposed to the atmosphere before serving may also result in loss of vitamin C. It is preferable to cook vegetables in minimum amount of water keeping the vessel covered and to consume it as soon as possible. Reheating cooked vegetables further destroys vitamins.
  • Such extra care can save precious nutrients. Instead of cooking only for taste and relish, we should try to get the most from our food.                                              

Tuesday, November 20, 2018

UNIT 7 - MENU PLANNING

Introduction

MEAL PLANNING involves planning a balanced meal which is colorful, attractive, appetizing, and palatable and within the economic means of the individuals concerned. A balanced diet is one which provides all the nutrients in the amount and proportion required according to one’s age, gender and activity.
Meal planning involves decision making regarding what to eat and how much to eat each day at each meal.
The meals planned should not only ensure that nutrients are adequately met but also be flexible enough to take advantage of easy availability and lower prices if seasonal foods and meet the needs and choices of family members.
As the health of an individual or a family depends on how well they are fed within the given resources, effective meal planning is a great challenge to every meal manager.

AIMS


  • To meet the nutritional needs of an individual who will be consuming the food.
  • Plan meals within the food cost.
  • Simplify purchase, preparation and storage of meals.
  • Provide attractive, appetizing meals.
  • Save time and money.

Importance of meal planning


  • Customer satisfaction
  • Facilitating costing
  • Facilitating pricing
  • Reference by customer and management
  • Guide production
  • Facilitate evaluation and improvements
  • Facilitate ordering
  • Plan storage
  • Guides the catering staff on how to  prepare dishes
  • Help the catering staff to prepare in terms  of attitudes, skills ordering etc.
  • Some menu requires special preparation  like decorations and equipment therefore  menu will help in availing the necessary.


Principles:

1. Budget
2. Nutrition
3. Time
4. Meal Appeal

BUDGET

It is necessary that one must plan meals and buy food wisely so as to achieve maximum nutrition from the money spent. For eg. As a source of protein pulses as compared to animal foods are relatively cheaper.

NUTRITION

Your health and well being is dependent on eating nutritious food.
TRY TO INCORPORATE EACH PART OF MYPLATE INTO ALL YOUR MEALS!
Focus on fresh fruits and vegetables, whole grains, and lean proteins.

TIME

HAVING LITTLE TIME DOES NOT MEAN YOUR MEALS NEED TO BE “FAST FOOD”.
PLAN AHEAD OR USE CONVENIENCE FOODS.
PRECUT FRUIT/VEGETABLES
SALAD MIXES
MICROWAVES, CROCKPOTS, DISHWASHERS AND FOOD PROCESSORS CAN BE TIME SAVING TOOLS!
MAKE MEALS AHEAD OF TIME
CROCKPOT
FREEZER
FAST COOKING METHODS
MICROWAVE
BROILING
ONE DISH MEALS
CASSEROLES

MEAL APPEAL CHARACTERISTICS


  • COLOR
  • SHAPE
  • FLAVOR
  • TEXTURE
  • TEMPERATURE

Meal Appeal Characteristics
Color- Combine different colors to make a meal interesting and vary the nutrients within the meal!
Shape- Contrasting shapes within a meal make it fun and appealing.
Flavor- Experiment with different flavors in a meal to stimulate the taste buds.
Texture- All meals should include a variety of textures. The texture can vary from soft, crunchy, smooth or chewy.
Temperature- Serving food at various temperatures is another way to add appeal to a meal. A cool side salad with a warm meal is one way to vary the temperature.

Meal Planning based on Food Group System

The first prerequisite of a good meal plan is to meet the nutritional needs of the individual and the family as a whole. No single food can meet all the nutrient requirements. A combination of different foods needs to be included in the diet.
For convenience in meal planning, different foods have been grouped under three food groups based on their function and major nutrient contributions.

  1. BODY BUILDING FOODS
  2. ENERGY GIVING              
  3. PROTECTIVE FOODS

ENERGY GIVING FOODS

This group includes foods rich in carbohydrate like cereals and their products, starchy roots and tubers and sugar and those rich in fat like nuts, fats and oils. Therefore the energy in our diet is mainly contributed by this group.
Cereals and nuts in addition to energy, contribute significant amount of proteins, minerals and B group vitamins.
Fats sugars besides being energy dense add palatability to the diet.

BODY BUILDING FOODS

This group includes food which provides proteins that are important for tissue building and maintenance.
Foods of animal origin like milk and its product, eggs, meat, fish, provide proteins of good quality.
Plant protein foods like pulses, legumes nuts and oilseeds have a relatively inferior quality of protein.
The foods of this group in addition to protein also contributes energy, vitamin A, vitamins of B groups and minerals.

PROTECTIVE FOODS

This group includes foods that provide ample amount of vitamins and minerals for protective regulatory function of the body.
All vegetables and fruits (except starchy roots and tubers) and fruits comprise this group.
Amongst vegetables most of the GLV’S are good source of iron, calcium, beta carotene, vitamin C and dietary fibre.
Deep yellow and orange colored fruits and vegetable are particularly rich in beta carotene and citrus fruits in vitamin C.
Hence, selection and inclusion of some foods from each of these food groups in every meal is important to provide all the essential nutrients for various body functions and to make the diet well balanced.

FOOD COST AND ECONOMY


  • It is necessary that one must plan meals and buy food wisely so as to achieve maximum nutrition from the money spent. For eg. As a source of protein pulses as compared to animal foods are relatively cheaper.
  • For economizing in meal planning, the following characteristics are important:
  • Compare the prices of food items to make best buy of money spent.
  • As far as possible buy food from fair price shops etc.
  • Buy only non-perishable foods in bulk.
  • Use seasonal foods as they are not only economical but nutritious also.
  • Cook the right amount to minimize wastage.
  • Go for economic substitutes within the same food groups. Eg. Choosing cereals and millets instead of bread and pasta.
  • Make proper use of leftover. 


ACCEPTABILITY OF MEALS

Acceptability of meals is as important as meeting nutritional needs and keeping the food cost within the budget. To make meals acceptable, following considerations are important during planning,
LIKES AND DISLIKES: while planning meals it is very important to keep in mind likes and dislikes of family /people.
VARIETY: the meals should have variety in color, texture, and flavour for better acceptability. Variety can be achieved by:
Selecting different foods from each food group.
Avoiding repetition of same food from particular food group.
Including a variety of vegetables in meals so as to incorporate colour.
Using different methods of cooking such as baking, boiling, frying etc. to bring about variety in texture.
Using attractive garnishes, toppings and accompaniments such as papad, pickles and relishes.
SATIETY VALUE: the meals planned should provide adequate satiety so as to prevent hunger till it is time to next meal. Sufficient amount of proteins, dietary fibre and fat helps to provide satiety in the meals.
TIME AND CONVINIENCE: selection of dishes should be done according to the availability of time.
FOOD HABITS AND RELIGIOUS BELIEFS
FOOD AVAILABILITY AND SEASONAL VARIATION: as far as possible seasonal and locally available food should be made use of. Vegetables and fruits in season are not only cheaper but have the highest content and best flavour.

FACTORS AFFECTING MEAL PLANNING

Several factors direct what kind of menu to  make

Nutrition requirements


  • Proteins
  • Starches
  • Vitamins
  • Fats
  • Mineral salts


Health consideration


  • Sickness
  • Availability of foodstuffs
  • Seasonal foods like Fruits Vegetables

Number of courses

  • Appetizer
  • Main dish
  • Dessert

Sequence of courses

Occasions

  • Funerals
  • Wedding
  • Birthday
  • Graduation Ceremony
  • National holiday celebration
  • Festivals


Thursday, November 15, 2018

UNIT 6 - BALANCED DIET

BALANCED DIET


When the diet is able to meet all the needs of an individual and also it provides an extra allowance for minor stresses and strains, the individual is said to be in a state of optimum nutrition.

OPTIMUM NUTRITION is also known as adequate nutrition or good nutrition.

GOOD NUTRITION thus provides all essential nutrients in correct balance which are further utilized to promote the highest level of physical and mental health. Such a state of nutrition can be attained through balanced diets.

BALANCED DIET can be defined as one which contains different types of foods (from all food group) in such quantities and proportions that needs for all the nutrients are adequately met and a small extra allowance is made as a margin of safety.

SAFETY MARGIN is taken into account due to individual variations, losses during cooking and processing and also minor illnesses.
Thus a balanced diet along with inclusion of various food groups focuses on the RDA for various nutrients.

RDA is defined as the estimates of intakes nutrients which individuals in a population group need to consume to ensure that the physiological needs of all subjects in that population are met.
RDA varies with age, sex, physiological state etc.

Factors affecting RDA

This nutritional requirement is influenced by –

  1. age
  2. growth 
  3. gender
  4. pregnancy
  5. breastfeeding
  6. illness
  7. psychological and emotional stress
  8. activity level
  9. smoking
  10. drinking.

IMPORTANCE OF BALANCED DIET

1. It includes variety of food items from all the food groups.
2. It meets the RDA for all nutrients
3. it provide safety allowances so as to withstand short duration of illness.
4. To maintain a state of positive health and optimal performance.
5. Prevents deficiency diseases.
6. Promotes and preserves health.
7. Promotes optimum nutrition thus maintains acceptable body dimensions.


DIGESTION, ABSORPTION, AND METABOLISM

• DIGESTION:
– Mechanical and chemical process in which food is broken down in the gastrointestinal (GI) tract, releasing nutrients in forms the body can use

• ABSORPTION:
– Process in which released nutrients are taken into the cells lining the GI tract

• METABOLISM:
– The sum of the body processes involved in converting food necessary for energy, tissue building, and metabolic controls

DIGESTION: BASIC PRINCIPLES

• Principle of Change
– The body cannot use food as it is eaten
– Food must be changed into simpler substances to be absorbed and then used by cells to sustain life

• Principle of Wholeness
– The parts of the digestive process comprise a continuous whole.
– Food components travel through the gastrointestinal (GI) system until they are delivered to cells or excreted

THE GASTROINTESTINAL SYSTEM
• A long muscular tube that begins with the mouth and ends with the anus (also called the alimentary canal or digestive tract)

UNIT 5 - WATER


What is water?

Water is a transparent, tasteless, odorless, and nearly colorless chemical substance.
It is vital for all known forms of life, even though it provides no calories or organic nutrients.
Water is the most essential constituent of our body. It has fundamental importance in both structure and functioning of all tissues. It accounts for 55-75% of our total body weight.
Lean individuals have more water than the obese, and infants and children have a greater proportion of water than adults.


DIETARY SOURCES OF WATER

1. VISIBLE SOURCES   - The water taken through drinks, plain water, fruit 
                                           juices, hot and cold beverages.

2 .INVISIBLE SOURCES- Water present in food stuffs like vegetables,
                                            whole   fruits, solid food contain varying
                                            percentage of water. 
 3. Apart from this body also contains metabolic water.  It is synthesized in the 
   body as a result of oxidation of macronutrients
The intake of fluid varies among people on the basis of age, gender, climate, physical activity etc.
Adequate amount of water need to be consumed to allow body to perform its daily functions.
8-10 glasses of water should be consumed daily i.e. 2-2.5 litres.

Daily losses of water from body

1. Insensible water loss- water loss which we are not consciously aware of, which occurs continuously in living beings.
loss by evaporation from skin
loss through respiratory tract
2. Through sweat- it depends on physical activity and temperature.

 3. Through urine- it is the most important mechanism by which the body maintains a balance between fluid intake and output.

       4. Loss in faeces- only small amounts of water is normally lost in  faeces, as re-absorption takes place.

FUNCTIONS OF WATER


  • The most important function is of quenching thirst.
  • It is a structural component of all cells. Water is present in bound form in bones and unbound form in most tissues, thus there is a constant interchange taking place between the body compartments of water.
  • It acts as a medium for all chemical reactions to take place.
  • It is an essential component of all body fluids such as blood, lymph, cerebrospinal fluid (CSF), bile, digestive juices and urine.
  • It acts as a lubricant and helps food to be swallowed and digested food to pass through the GIT (gastro intestinal tract).
  • Water regulates body temperature by taking up and distributing heat being produced in cells when metabolic reactions take place.
  • It helps in excreting waste products of the metabolic reactions.
  • It is important to maintain turgidity of cells.


WATER BALANCE

Water intake/ input  =  Water output
Water available through dietary sources and from food metabolism and the loss of water through bodily processes maintains water balance.

When water balance is disturbed then following conditions arises
Dehydration
In situation where water output increases than water input i.e. there is excessive loss of water from body due to conditions like diarrhea, vomit, fever, diabetes, it can lead to dehydration.
A dehydrated person feels thirsty, has dry mouth, sunken and dry eyes, restless, irritable and can also lead to unconsciousness.
The condition is managed by giving ORT(oral rehydration therapy).
In ORT  oral rehydration solution (ORS) is dissolved in 1 liter of water. It is given till the person body gets normally dehydrated.
Odema
When water input increases than output in such a condition retention of water in body takes place and thus salts are also retained in the interstitial fluid giving rise to swelling of the skin.
This condition of retention of water and salt in interstitial fluids is ODEMA
Its characteristic feature is, when pressure is applied to swollen skin a depression is formed.

MAINTAINING WATER BALANCE

In the body, several mechanisms work together to maintain water balance. These include

Thirst

Thirst is one of the most important mechanisms to maintain water balance. When the body needs water, nerve centers deep within the brain are stimulated, resulting in the sensation of thirst. The sensation becomes stronger as the body’s need for water increases, motivating a person to drink the needed fluids. When the body has excess water, thirst is suppressed.

Interaction of the pituitary gland and kidneys

An interaction between the pituitary gland and the kidneys provides another mechanism. When the body is low in water, the pituitary gland (located at the base of the brain) secretes vasopressin  into the bloodstream. Vasopressin stimulates the kidneys to conserve water and excrete less urine. When the body has excess water, the pituitary gland secretes little vasopressin, enabling the kidneys to excrete excess water in the urine.

Osmosis

In osmosis, water flows passively from one area or compartment of the body to another. This passive flow allows the larger volumes of fluid in the cells and the area around the cells to act as reservoirs to protect the more critical but smaller volume of fluid in the blood vessels from dehydration.

Sunday, November 11, 2018

UNIT 4 - MICRO NUTRIENTS (Minerals)

MINERALS

Minerals are natural compounds formed through geological processes. Minerals are needed by the body in small amounts to help it function properly and stay strong. Iron, calcium, potassium, and sodium are some of essential minerals. Humans need small amounts of about 14 minerals to maintain normal body function and good health.

The 14 minerals essential to human health are:
 Macro Minerals          
1. Calcium
2. Phosphorus
3. Magnesium
4. Sodium
5. Potassium
6. Chloride
7. Sulfur
Micro/Trace Minerals
1. Iron
2. Manganese
3. Copper
4. Iodine
5. Zinc
6. Fluoride
7. Selenium

These 14 essential minerals are crucial to the growth and production of bones, teeth, hair, blood, nerves, skin, vitamins, enzymes and hormones; and the healthy functioning of nerve transmission, blood circulation, fluid regulation, cellular integrity, energy production and muscle contraction.
Minerals are neither animal nor vegetable; they are inorganic. Almost all foods contribute to a varied intake of essential minerals. Most minerals are easy to obtain in quantities required by the body. The study of minerals is called mineralogy.

Types of Minerals

There are two types of minerals: Macro minerals and Trace minerals.

1. Macro Minerals
Macro means "large" in Greek are dietary minerals needed by the human body in high quantities. The macro mineral group is made up of Calcium, Phosphorus, Magnesium, Sodium, Potassium, Chloride, and Sulfur.

2. Micro / Trace Minerals
Micro minerals, also known as trace elements are micronutrients that are chemical elements. A trace of something means that there is only a little of it. So, even though your body needs mineral each day in small amounts for good health. Scientists aren't even sure how much of these minerals you need each day. Trace minerals includes Iron, Manganese, Copper, Iodine, Zinc, Fluoride, and Selenium.


CALCIUM


Calcium is the most abundant mineral in the human body and has several important functions.
Calcium is the top macro mineral when it comes to your bones.
This mineral helps build strong bones, so you can do everything from standing up straight to scoring that winning goal.
Calcium is a primary structural constituent of the skeleton, but it is also widely distributed in soft tissue where it is involved in neuromuscular, enzymatic, hormonal, and other metabolic activity.

Calcium absorption is dependent upon the calcium needs of the body, the foods eaten, and the amount of calcium in the foods eaten. Vitamin D from diet or exposure to the ultraviolet light of the sun increases calcium absorption. Calcium absorption tends to decrease with increased age for both men and women. More than 99% of total body calcium is stored in the bones and teeth where it functions to support their structure. The remaining 1% is found throughout the body in blood, muscle, and the fluid between cells.

Overdose Disease of calcium: Constipation and lack of appetite

Deficiency Diseases of calcium: Arthritis, High Blood Pressure, Osteoporosis

Deficiency Symptoms of calcium:

Because bone stores of calcium can be used to maintain adequate blood calcium levels, short-term dietary deficiency of calcium generally does not result in significantly low blood calcium levels. But, over the long term, dietary deficiency eventually depletes bone stores, rendering the bones weak and prone to fracture. The symptoms of calcium deficiency are:
Bowlegs, and Knock-knees of children
Cramp pains in legs
Delay in sitting up, Crawling and Walking of babies
Nerves become extremely irritable
Poor sleep disorder
Weakness in the bones

Rich Sources of calcium:

Dairy Products, such as Milk, Cheese, and Yogurt
Canned Salmon
Leafy Green Vegetables, such as Broccoli, Spinach
Ice Cream, Oysters
Individuals two years and older should eat 2-3 servings of dairy products per day. A serving is equal to:
o 1 cup (8 fl oz) of milk
o 8 oz of yogurt
o 1.5 oz of natural cheese
o 2.0 oz of processed cheese
Although dairy products are the main source of calcium in the diet, other foods also contribute to overall calcium intake. A person may have to eat several servings of certain foods such as spinach to obtain the same amount of calcium in one cup of milk, which is not only calcium-rich but also contains calcium in an easily absorb able form.

Calcium is Important for:

Formation of bones and teeth
Coagulation of blood
Contraction of muscles, Cardiac action
Young mothers during pregnancy and the nursing period
Children and young people for rapid growth of bones

PHOSPHORUS

Phosphorus is the second most abundant mineral in the body and 85% of it is found in the bones. The rest of the body's phosphorus is found in the blood. It is found in the body usually at a ratio of 1:2 to calcium. It is nonmetallic element that is found in the blood, muscles, nerves, bones, and teeth and is a component of adenosine tri-phosphate

Deficiency Diseases: Rickets, Osteoporosis, Stiff joints and Pain in the bones. It can also cause anxiety, irritability, sensitive skin, stress, tiredness and weak teeth etc.

Deficiency Symptoms:

Weak or fragile bones & teeth
Fatigue, weakness
Loss of appetite
Joint pain and stiffness
Less energy and a susceptibility to infections

Rich Sources:

Milk, Yogurt, Cottage cheese, American cheese, Pork, Hamburger, Tuna, Lobster, Chicken, Sunflower seeds, Peanuts,  Peanut butter, Bran flakes, Shredded wheat, Whole wheat bread, Noodles, Rice, White bread, Potatoes, Corn, Peas, French fries, Broccoli, Milk chocolate and Soda beverages (due to the phosphoric acid added as a preservative)

Important for:

Growth, maintenance, and repair of cells, and the production of energy
Maintain the pH level (acidity-alkalinity) of the blood
Reduces pain of arthritis
Speedy recovery of burn victims
Cancer prevention
Building of strong bones and skeleton structure
Maintain heart regularity

Recommended Daily Intake: Men & Women: 1000 mg

IRON


Iron is part of hemoglobin, the oxygen-carrying component of the blood. Iron helps because it's important in the formation of hemoglobin, which is the part of your red blood cells that carries oxygen throughout the body. Although iron is part of the antioxidant enzyme catalase, iron is not generally considered an antioxidant, because too much iron can cause oxidative damage.

Functionality:

The body needs iron to transport oxygen from your lungs to the rest of your body. Iron is necessary for production of hemoglobin, and oxygenation of red blood cells, builds up blood quality, and increases resistance as well as increasing energy production. Iron also forms part of several enzymes and proteins in the body.

Deficiency Diseases:
Anaemia


Overdose Disease: Cancer, Liver & Heart damage, Diabetes & Skin Changes


Deficiency Symptoms:

Lethargy, poor concentration
Pale skin and shortness of breath
poor stamina
Intestinal bleeding
Nervousness
Heart palpitations

Rich Sources:
Iron is found in Meat, Fish, Beans, Spinach, Molasses, Brewer's yeast, Broccoli and Seeds.

Important for:
Formation of haemoglobin
Brain development
Regulation of body temperature
Binding oxygen to the blood cells

Recommended Daily Intake:
Men: 10 mg
Women: 18 mg

IODINE

Functionality:
Iodine's primary function is to keep the thyroid gland healthy and manufacturing sufficient thyroxine, a hormone that is needed throughout the body.

Deficiency Diseases: Acne, Bad Circulation, Confused Thinking, Goiter, Hormonal Imbalance, Miscarriages, Scaly or Dry Skin, Weight Gain and Weight Loss etc.

Overdose Disease: Hyperthyroidism

Deficiency Symptoms:
Apathy, Drowsiness
Hair loss, Fatigue, Dry skin
Increased blood fats
Delayed reflexes, and reduced mental clarity

Rich Sources:
Iodine is added to most table salt so people generally get the required amount from just one teaspoon of iodized salt. Other Iodine sources include eggs, milk, sea fish and sea food, sea vegetables - such as kelp, seaweed, asparagus etc. Fruits and vegetables grown in coastal regions are other good sources of iodine.

Important for:
Thyroid gland to produce thyroxine
An important hormone for growth and metabolism
Prevention of goitre

Recommended Daily Intake:
Men & Women: 0.5 mg
Females require higher iodine amounts during pregnancy.

FLUORIDE

The Fluoride mineral is one of the families of trace minerals and is one mineral that is surrounded by controversy. Although the fluoride mineral is not considered as essential, it certainly plays a significant role in keeping teeth and bones healthy and strong.

Functionality:

It helps in the fight against tooth decay. Teeth need a way to fight tooth decay and fluoride is the best weapon. It's believed that this function plays a big role in protecting a person against the onset of osteoporosis.

Deficiency Diseases:

Cavities and Weakened tooth enamel
Overdose Disease: Dental fluorosis

Deficiency Symptoms:

Appearance of dental carries, better known as cavities
Weakened tooth enamel
Brittle bones

Rich Sources:

Fluoride sources are not at all common and the fluoride mineral is not found in many of the foods that we eat. That is why it has been added to toothpaste and some drinking water supplies. Canned fish, including their edible bones, such as salmon is also a good source of the fluoride mineral.
Important for:
Preventing dental caries
Preventing osteoporosis
Recommended Daily Intake:
Men & Women: 1 mg

SODIUM

The Sodium is also known as salt, has been getting a lot of attention over recent years, attention which has been mainly negative. It is still classed as a major mineral and is very important that the body receives its quota every day in order to function correctly.

Functionality: It is required in the manufacture of hydrochloric acid in the stomach, which protects the body from any infections that may be present in food.

Deficiency Diseases: Diarrhea, Vomiting
Overdose Disease: High Blood Pressure, Hypertension

Deficiency Symptoms: 
Sodium deficiency is rare but Symptoms of a sodium deficiency that is combined with a loss of water includes:
Muscle cramps and weakness
Dizziness
Inability to concentrate
Memory impairment and nausea

Rich Sources: Sodium is found in Table Salt, Anchovies, and Bacon etc.
Important for:
Maintaining blood pressure
Regulates fluids and acid-base balance in the body
Nerve transmission and muscle contraction
Treatment of diarrhea, leg cramps, dehydration, and fever

Recommended Daily Intake: Men & Women: 2400 mg

POTASSIUM

Potassium is the third most abundant mineral in the body and is considered an electrolyte. Potassium keeps your muscles and nervous system working properly.

Deficiency Diseases:
Fatigue, Cramping legs, Muscle weakness, slow reflexes, Acne, Dry skin, Mood changes, Irregular heartbeat.

Overdose Disease: Kidney failure

Deficiency Symptoms:
Weakness
Scarring of heart muscle, Irregular heartbeat or heart failure
Hypertrophy of kidneys
Paralysis of muscle
Retarded bone growth

Rich Sources:
Bananas, Broccoli, Tomatoes, Potatoes with skins, Kiwi, Leafy green vegetables, Broccoli Citrus fruits, Oranges, Dried fruits, Dates, Apricots, Avocado, Beans, Peas, Lentils, and Peanuts are rich sources of Potassium.

Important for:
Regulates heartbeat
Maintains fluid balance
Helps muscles contract
Helps in lower blood pressure
Dispose of body wastes
Recommended Daily Intake:
Men & Women: 3500 mg

MAGNESIUM

The Magnesium is one of the families of major minerals although it is not as well known as some of the other minerals in the same group. Even though it is not as prominent, the magnesium mineral plays an essential role in about three hundred biochemical processes that take place inside the body.

Functionality:
It is essential to maintain both the acid-alkaline balance in the body and healthy functioning of nerves and muscles

Deficiency Diseases: Heart disease, Diabetes and Osteoporosis.

Overdose Disease: Kidney failure

Deficiency Symptoms:
Nausea
Vomiting
Loss of appetite
Fatigue and a feeling of weakness

Rich Sources:
Dark green vegetables such as Spinach, Broccoli and Avocado are excellent magnesium sources. Other magnesium sources include Whole grains, Legumes, Black beans, Brown rice, Lentils, Almonds, Cashews, Peanuts and Peanut butter, Bananas, Soybeans, Wheat bran and Bran flakes, Lean meats, Dry figs, Halibut, Crab and Sardines.

Important for:
Lowers high blood pressure
Promotes healthy cardiovascular system to prevent heart disease and arrhythmia
Calcium deposits, kidney stones, and gallstones
Relief from indigestion
Inhibits blood clots
Diabetes Prevention
Relaxes muscles and reduces severity of asthma by widening the airways

Recommended Daily Intake:
Children: 80-240 mg
Men: 350 mg
Woman: 300 mg
Pregnancy: 350-400 mg
Lactation: 310-360 mg


Other Mineral Elements

Mineral Function Sources
Sulfur Found in protein molecules Occurs in foods as part of protein: meats, poultry, fish, eggs, milk, legumes, nuts

Zinc Part of many enzymes; needed for making protein and genetic material; has a function in taste perception, wound healing immune system health Meats, fish, poultry, leavened whole grains, vegetables
Selenium Antioxidant
Meats, seafood, grains
Copper Part of many enzymes; needed for iron metabolism Legumes, nuts and seeds, whole grains, organ meats, drinking water
Manganese Part of many enzymes Widespread in foods, especially plant foods

Other trace nutrients known to be essential in tiny amounts include nickel, silicon, vanadium, and cobalt.

Thursday, October 11, 2018

UNIT 3 - MACRO NUTRIENTS (Proteins)

Introduction

Protein is the basic material of every living cell. It is the only nutrient that can make new cells and rebuild tissues. Therefore, an adequate amount of protein in the diet is essential for normal growth and development and for the maintenance of health.

Definition


  • Proteins are large, complex, organic compounds made up of carbon, hydrogen, oxygen, and nitrogen. The presence of nitrogen distinguishes proteins from carbohydrates and fats. Apart from nitrogen, elements such as sulphur, phosphorus, copper, and iron are also found in some proteins.
  • They are composed of one or more chains of amino acids. 
  • Proteins are fundamental components of all living cells and include many substances, such as enzymes, hormones, and antibodies that are necessary for the proper functioning of an organism. 
  • They are essential in the diet of animals for the growth and repair of tissue and can be obtained from foods such as meat, fish, eggs, milk, and legumes.

Basic Structure of a Protein

Proteins are made up of hundreds or thousands of smaller units called amino acids, which are attached to one another in long chains.
There are 20 different types of amino acids that can be combined to make a protein. 9 are essential and 11 are non essential.
The sequence of amino acids determines each protein’s unique 3-dimensional structure and its specific function.
The bond which unites the two amino acids is called a peptide bond.
 One amino acid has
1 carboxyl group (COOH)
1 amino group or nitrogen group (NH2)
1 hydrogen (H)
And 1 functional group (R)

NH2CHRCOOH.


Amino Acids

Essential amino acids

Those amino acids which cannot be synthesized in sufficient amounts by the body and must be provided by the diet are called essential amino acids. The human adult requires eight essential amino acids, while growing children require ten essential amino acids. Essential amino acids are indispensable to life.


  1. Isoleucine
  2. Leucine
  3. Lysine
  4. Methionine
  5. Phenylalanine
  6. Threonine
  7. Tryptophan
  8. Valine
  9. Histidine (for children)
  10. Arginine (for children)


Non essential amino acids

Non-essential amino acids do not mean that these amino acids are not required by the body. They are termed non-essential because they are not dietary essentials. If they are lacking in the diet, they can be synthesized by the body from other amino acids.

  1. Alanine
  2. Aspargine
  3. Aspartic Acid
  4. Cysteine
  5. Glutamine
  6. Glycine
  7. Hydroxylysine
  8. Hydroxyproline
  9. Proline
  10. Serine
  11. Tyrosine


Classification of protein based on origin



Classification of protein based on characterization


Classification of protein based on function


Dietary Sources of Proteins

Proteins are present in both plant and animal foods.

Animal food sources
Animal food sources provide the highest quality or complete proteins such as eggs, milk and milk products (cheese, paneer, mawa, milk powder, curds, condensed milk),meat, fish, shellfish, poultry, and organ meat.
Plant food sources

  • Pulses, especially soya bean (43 per cent protein) and its products such as soya milk textured vegetable proteins: nuts and oilseeds-groundnuts and gingelly seeds are important sources of protein in the Indian diet. 
  • Cereals contain 6-12 per cent partially complete proteins and as they form bulk of the diet, they contribute significantly to the protein content.
  • Vegetables contain a small percentage of good quality protein (approx 1-3 percent).
  • Fruits do not contribute towards protein content of the diet.


Functions of Proteins

Proteins perform three main functions

  1. Structural function 
  2. Regulatory function 
  3. Energy 


Structural function

Growth: The primary function of food protein is the synthesis of body cells. Proteins are the major constituent of muscles, organs, endocrine glands, and collagen. Collagen is the main structural protein of bones, tendons, ligaments, skin, blood vessels, and connective tissue. All enzymes and some hormones, e.g., insulin are made up of proteins. Proteins are required for the formation and growth of all these substances. During periods of rapid growth, additional proteins are needed for synthesis of body components.
Maintenance or wear and tear: Protein is required by all age groups for continuous maintenance of all the cells in the body. Cells have a varying life span and proteins are needed to replace the old or worn out cells.

Regulatory function


  • All amino acids from food protein are used for growth and maintenance. Certain amino acids and proteins have highly specialized functions in the regulation of body process and protection against disease. Some of the regulatory functions are as follows.
  • Haemoglobin, an iron containing protein in the red blood cells, performs an important role by transporting oxygen to the tissue cells. 
  • Plasma proteins maintain water balance and regulate the osmotic pressure in the body. 
  • Antibodies that are protein in nature perform a protective function by increasing the body’s resistance to disease. 
  • All enzymes and some hormones, e.g. insulin are made up of protein. The hormone insulin regulates blood sugar levels. Enzymes act as specific catalysts to metabolic process in the body.  
  • Some amino acids have specific functions, e.g. tryptophan serves as a precursor for niacin, a complex vitamin. The amino acid tyrosine in combination with iodine forms the hormone thyroxine. 


Energy


  • Like carbohydrates, proteins too provide 4 kcal/g when broken down in the body. If the diet does not supply adequate calories from carbohydrates and fats, the proteins from the diet will be oxidized to meet the energy needs of the body. Protein is used by the body as a source of energy only when no other source of energy is available.

Methods of improving protein quality


  • Animal protein contains all essential amino acids in correct proportions and amounts and is good quality proteins. Four essential amino acids are in short supply in plant proteins. They are lysine, methionine, threonine, and tryptophan. Proteins in plant foods are generally deficient in one or two essential amino acids. Cereals are poor in lysine and pulses are poor in methionine.
  • Protein will be synthesized only when all amino acids, which form the protein, are present simultaneously. Vegetable proteins are partially complete proteins. These two points should be kept in mind while improving the protein quality of a meal.

The protein quality of a mainly vegetarian diet can be improved in the following ways.

  1. By including a small quantity of complete protein food in every meal. Complete protein foods such as milk, curds, paneer, cheese, buttermilk, and eggs could be used in small quantities in various preparations instead of including it in one meal only, e.g. cereal and milk, egg or cheese sandwiches, french toast, raitha, curd rice, or buttermilk at all meals in place of bowl of curd in one meal. 
  2. Correct mixtures of plant foods could provide all essential amino acids in suitable proportions and amounts. Cereal and pulse combinations will complement each other as cereals provide methionine, which is lacking in pulses, and pulses provide lysine, which is lacking in cereals, when cereal and pulses are consumed together in the same meal, e.g. missie roti, thalipeeth, puran poli, idli, and rajma chawal. This is possible because the same amino acids are not missing from all plant foods. 
  3. Synthetic amino acids may be added to processed foods to compensate for the amino acid deficient in them, e.g., lysine enriched bread. Textured  vegetable proteins are used successfully to improve the protein quality and reduce the cost of protein rich foods.
  4. When plant proteins are consumed with a small quantity of animal protein, the quality of the mixture is likely to be as effective as if only animal protein has been consumed. A good rule while planning menus would be to include some animal proteins at each meal instead of concentrating it all in one meal.


Whey Protein


  • Whey protein is a mixture of proteins isolated from whey, which is the liquid part of milk that separates during cheese production.
  • Milk actually contains two main types of protein: casein (80%) and whey (20%).
  • Whey is found in the watery portion of milk. When cheese is produced, the fatty parts of the milk coagulate and the whey is separated from it as a byproduct.
  • If you've ever opened a yogurt container to see liquid floating on top — that’s whey. Cheesemakers used to discard it before they discovered its commercial value.
  • After being separated during cheese production, whey goes through various processing steps to become what people generally recognize as whey protein — a powder that is added to shakes, meal replacements and protein bars .
  • Whey protein doesn't taste very good on its own, which is why it’s usually flavored. Chocolate-, vanilla- and strawberry-flavored powders are popular.
  • It's important to read the ingredients list, as some products may have unhealthy additives like refined sugar.
  • Taking whey protein is a convenient way to add 25–50 grams of protein on top of your daily intake.
  • This can be important for bodybuilders and gym enthusiasts, as well as people who need to lose weight or are simply lacking protein in their diet.


Soy Protein


  • Soybeans are among the best sources of plant-based protein.
  • The protein content of soybeans ranges from 36 to 56% of the dry weight .
  • One cup of boiled soybeans (172 g) contains around 29 grams of protein .
  • The nutritional value of soy protein is good, although the quality is not quite as high as animal protein .
  • The main types of protein in soybeans are glycinin and conglycinin, which make up approximately 80% of the total protein content. These proteins may trigger allergic reactions in some people.
  • Consumption of soy protein has been linked with a modest decrease in cholesterol levels.




UNIT 4 - MICRO NUTRIENTS (Vitamins)

What are Vitamins?


  • Organic molecules with a wide variety of functions
  • Cofactors for enzymatic reactions
  • Essential, supplied in the diet
  • Two distinct types: Fat soluble (A, D, E, K)
  • Water soluble (B – complex, C)

Vitamins are organic molecules that are essential for normal  health and growth. They are required in trace amounts and must  be obtained from the diet because they are not synthesized in the  body. Before vitamins were discovered, it was known that lime  juice prevented the disease scurvy in sailors and that cod liver oil  could prevent rickets. In 1912, scientists found that, in addition to  carbohydrates, fats, and proteins, certain other factors called  vitamins must be obtained from the diet.







































Source: https://www.slideshare.net/syed_ismail/vitamins-29442747

Author : Dr. Syed Ismail Ibrahim, Professor

Published on: Dec 23, 2013