Bsc 1st Year -Aims and Objectives of Cooking

AIMS AND OBJECTIVES OF COOKINF FOOD –NOTES

 

 

 

What does ‘cooking’ mean?

Can cuccumbers and salads be called ‘cooked foods’?

 

Cooking means exposing food materials to heat. The medium of transfer of heat from its source could be water, air or oil. This will be dealt with in detail at a later stage. First let us understand why we need to ‘cook’ food.

 

In the ancient times, human beings ate / consumed raw meats and other foods like roots and fruits. It was much later after the fire was invented that the concept of ‘cooking’ was known. It is believed that food accidentally fell in the fire and thus the discovery of cooked food. Today we do eat some food in the uncooked (raw) form; though, mostly we associate food with its cooked form.

A. Aims and objectives of cooking food:

1. Making food safe for consumption – Cooking sterilizes food partially. The growth of bacteria gets restricted at 40^oC (104^oF). Non-sporing bacteria are killed at temperatures above 60^oC (140^oF). For example, pasteurization – milk is made safe by holding it at 63^oC (145^oF) for 30 minutes or at 72^oC (161^oF) for 15 seconds. Boiling kills living cells. Spore-bearing bacteria take 4-5 hours of boiling to be destroyed.

2. Making food more digestible – Complex foods are split into simpler substances during cooking. The human body can absorb and utilize these more readily.

3. Increasing palatability

4. Making food look better – Heat brings about changes in colour, texture and overall appearance of the food, making it more appetizing.

5. Introducing variety – A single ingredient may be used in many different ways, cooked by different methods and bring about changes in the meal.

6. Balancing a meal – Different ingredients combined in one dish make it easier to provide a balanced meal – i.e. providing all the required vital nutrients to the consumer.

B. Various textures:

As explained above, raw foods get exposed to some form of heat and then are called ‘cooked’ for consumption. The term TEXTURE is used to describe the characteristics of a finished (ready-to-eat) food product. The final product will have a certain texture depending on

· the order in which ingredients are added

· the way of mixing

· the method of cooking

A correct texture has to be brought about in the food. The chef should not only know the correct texture, but should be able to produce the same in the food. The various textures which are listed down, are difficult to explain in words, they should be felt and understood better. There are very thin differences between some of these, which one should learn better during practical.

1. Firm and close – biscuits and plain short pastries can explain this texture. Raising agents are used while preparing these, but they do not make the product very light or brittle. In fact they are hard as a result of many tiny air bubbles created by raising agents. But the biscuits are not too hard either, because of the fat included.

2. Short and crumbly – nankhatai and tarts are good examples of this texture. Fat included is more than that in biscuits, so it breaks more easily into smaller particles.

3. Spongy – Swiss rolls, sponge cakes, idli and dhokla are spongy. A soft, elastic texture due to incorporation of more air results in this texture.

4. Light – Madeira cake has plenty large holes in it, making it ‘light’. It is firm, but not hard and tough. It is neither as short as a tart nor as spongy as a Swiss roll.

5. Flaky – chiroti, lacchha paratha, chicken or veg puffs and khara biscuits are flaky. Thin, crisp layers are formed by spreading fat in between two layers of dough which get separated during baking / frying and remain separated due to air pockets. The flakes by themselves should not be tough / hard. Ideally the layers break easily and melt in the mouth.

6. Coarse – large and uneven holes are a result of too much of the raising agent or too little liquid. This is not a good texture to have in food; in fact, it is something to be avoided. Such cakes and other products are sunken at the centre.

7. Tough – too much liquid, over mixing, incorrect mixing, too little fat and long cooking time could result in toughness in food. Mostly, like the coarse texture, this also is to be avoided.

8. Hard – another texture which should be avoided as far as possible. In fact, it is considered to be a fault in the product. Too much pressure while mixing, excessive liquid in the product and incorrect quantity of fat result in this texture. Air that is incorporated gets removed out of the mixture, making the final product hard.

 

C. Various consistencies:

Like different textures found in solid foods (which are mentioned above), different ‘consistencies’ are found in liquid foods.

Some substances flow readily, others resist flow and some require force or weight application to start flow. The concept of consistency is closely related to viscosity.

Factors affecting consistency of liquid are –

· concentration (of thickening agent)

· temperature

· degree of dispersion

· mechanical treatment

· time (how long is it after preparing)

Generally speaking, the following consistencies could be found in liquid foods –

A. Pouring – like water and milk. These do not show any resistance and flow easily / readily. Stocks and some thin soups like consommé are examples of ‘cooked’ liquids having pouring consistency.

B. Coating – when a starchy thickening agent is mixed with a liquid, and the mixture is heated, the starch gelatinizes. In case of a protein as a thickening agent, it coagulates when exposed to heat. In both these cases, the liquid starts to thicken. If a spoon is dipped in this mixture, it starts coating the spoon. A thin film of the mixture could be seen in the beginning. Later on it goes on becoming visibly thicker. Depending upon one / more factors listed before, the thickening will take place up to a certain point. While making basic custard, this will be understood better. Here, liquid is milk and thickening is egg yolk. Similar coating consistency could be observed in kadhi where liquid is buttermilk and thickening is gram flour (besan)

The liquid is proportionately more than the flour or thickening agent.

C. Dropping – when a liquid is added to dry flour, it forms lumps as only some flour (granules) gets combined with liquid. Later, when added more liquid, it converts into dough and with some more liquid, it turns into ‘batter’. Here, the amount of solid (flour) is more than the liquid. For example, a cake mixture of fat, sugar, egg and flour is moistened with water or milk. Only that much liquid is required which will make the mixture fall out in a big moist smooth lump. The liquid should be dispersed well to get a smooth mixture. When you make cake batter in the bakery class, you will understand it better. Also, next time when you are waiting for your (batata)vada-pav, don’t forget to observe the vender making and using the batter.

 

 

 

D. Techniques used in pre-preparation:

Raw materials used in food production are mostly natural products. They are available in various shapes and weights. For example, no two potatoes or onions will be same in size, shape and weight. No two red pumpkins will be of the same size, shape and weight. Preparing a finished product calls for basic uniformity in size, shape and weight. This is the base for uniformity in cooking and also the appearance of the food. Breaking down the raw materials into required form is called ‘prepreparation’. Following are a few prepreparation techniques –

· Washing – superficial dirt is removed during washing. Vegetables, fish, meat and sometimes even eggs are washed with cold water before any other process. These days this is done at the very entrance of the store to prevent any dirt and mud entering in the store / kitchen / workplace. Water soluble vitamins and minerals are lost if they are soaked for a long period of time or washed after cutting.

· Peeling and scraping – spoilt, soiled and inedible portions are removed. Skins of potatoes, carrots, radish or fruits can be removed by peeling. Smaller ingredients like ginger, galangal are scraped. Peel off as little of the fleshy part as possible. If vegetables like carrots are washed well, their peels could be used for making stocks.

· Paring – remove surface layers by using a circular motion as in paring an apple.

· Cutting – reducing to smaller parts with a knife or a pair of scissors. When a chopping knife or a food chopper is used, it is termed as chopping.

Cutting into even size cubes --- --- --- dicing.

Cutting into very fine pieces --- --- --- mincing.

Cutting (especially green leafy vegetables &

cabbage) into fine, long pieces --- shredding.

Cutting into slightly thicker, flat pieces --- slicing.

· Grating – reducing to fine particles by rubbing over a rough, sharp surface.

· Grinding – reducing to fine fragments by crushing in a mill, a grinding stone or an ostirizer.

· Mashing – breaking up soft foods like cooked potatoes. {SMASHes are in boxing, NOT is food production}

· Sieving – passing through a mesh to remove impurities or to break down into even parts or to enclose air.

· Milling – used for cereals, to remove husk.

· Steeping – extracting colouring or / and flavouring by allowing ingredients to stand in water at a simmering temperature.

· Centrifuging – Separate two parts of a substance by application of whirling force like separation of cream from milk.

· Emulsification – Blending or mixing to non-mixable (insoluble) liquids by application of force.

· Evaporation / Reduction – removal of moisture by heating.

· Homogenization – subdivision of large drops into smaller ones by forcing them through a small opening under great pressure.

 

E. Techniques used in preparation:

When raw materials are ready to be cooked, they are sent to the preparation area or hot section of the kitchen where it gets exposed to heat. Following are some of the techniques in preparation. List may be enriched as and when you start actual cooking.

· Stirring – this mixes two or more ingredients as they get cooked. Wooden / stainless steel flat spoons, round spoons, perforated spoons etc. of various sizes could be used. Liquids as well as solid and semi-solid ingredients need stirring. Generally it helps in even dispersion of heat leading to even cooking.

· Masking – to prevent food from getting burnt in case of baking / roasting, it needs to be masked with some other food material. It can also be done to get a desired colour and appearance.

· Coating or dipping in batter – as mentioned earlier, batter is a mixture of flour and liquid (mostly equal quantities). Certain foods are dipped in batter and deep fried. The most apt example would be potato vadas. The batter should coat the stuffing fully and not expose any stuffing. This needs skill, because food should be dropped in hot oil immediately after dipping in batter. So, in a split of a second, the process has to be completed. Thus, the consistency of the batter plays a very important role.

· Basting – this is a technique which goes hand in hand with roasting. This means to apply fat / butter on the food while being roasted. It helps by protecting the surface from going dry and also by giving a pleasant brown colour to the roasted food.

· Tadka / baghar – these terms and technique are used in Indian cuisine. Oil is heated to the required temperature and certain spice ingredients are added to it (which should crackle,) then the food (like cooked dal or chopped vegetables) are combined with this. It develops additional taste and flavour to the dish. A peculiar flavour which is the characteristic of the dish can be added through the ingredients in the tempering.

Sometimes, continental dishes, especially rich soups and sauces are also ‘tempered’; but the technique is applied for a different purpose and using different ingredients. A mixture of egg yolk and cream (liaison) is added to a dish to enrich it, to give it a glaze and to make it smooth. A little of the hot soup / sauce is first mixed with the liaison, and then it is slowly stirred into the larger quantity of soup / sauce.

· Seasoning – seasonings bring about the natural taste and flavours of the ingredients. No dish can be complete without seasonings.

· Flavouring – these are those ingredients which impart additional flavours in the dishes. Nutmeg powder in creamed potatoes, cardamom powder in Indian sweets like kheers, vanilla essence in vanilla buns are some of the examples. Flavourings could be added in various forms – powders, drops or whole spices (which are removed before serving the dish to guest).