Tempering the eggs

Once milk/cream mixture have been flavored, it’s time to add the eggs. Tempering is the process of slowly adding a hot liquid to eggs in a recipe, in order to gradually raise the temperature thus slowly exposing eggs to heat without the danger of coagulation.

In this manner, the eggs do not curdle and produce an unacceptable consistency. If the eggs are not properly tempered the hot liquid will cook them, making final product uncomfortably reminiscent of scrambled eggs.

Overheating eggs in sauces, puddings and soft custards can be avoided by tempering the eggs. For sauces and puddings, cook the starch first - it needs extra time to thicken and lose its raw taste – then add the eggs.

Egg also can be tempered with hot liquid milk, is carefully streamed into them, bringing the eggs up to a very high temperature without cooking them.
Tempering the eggs

Manufacture of cranberry sauce

Large amounts of cranberries are used to produce cranberries jelly and cranberry sauce, both retailed as canned products.

The forts can cranberry sauce was packed in Hanson, Massachusetts in 1919, about 100 years after cranberry cultivation began in North America.

In the manufacture of cranberry sauce, water, about twice, as much as fruit and about 0.3% of dispersed pectin are mixed together.

The mixture is then cooked to 102.2 ° C and evaporated in an open steam kettle to a soluble solids content of 65%. Citric acid solution is then added to bring the pH to 3.0 – 3.4.

Whole cranberry sauce should not be cooked to a point where it sets to a solid gel, but should flow slowly when poured into a dish.
Manufacture of cranberry sauce

Process of microwaving the food

The absorption of microwave by a dielectric material results in the microwaves giving up their energy to the materials with a consequential rise in temperature. Food composition (mainly water content) is a key factor that determines how fast it will heat in a microwave environment.

Cooking food using a microwave oven is accomplished by setting an appropriate amount of time necessary for the waves to penetrate the food and cook it.

The most important advantages of microwave heating is that microwaves are capable of penetrating very deeply into certain materials heating extend within the entire food material, which result in very significant reductions in process heating times for drying, thawing, sterilization and so on.

There are limits to the depth of their penetration. The geometry of the food to be heated is an important consideration; conduction and convection may often take far longer to heat a given mass of food.

Microwaves generate heat due to their interactions with the food materials. The microwave radiation itself is non-ionizing radiation, distinctly different from ionizing radiation such as X-rays and gamma rays.

Heating foods evenly in a microwave oven is difficult at best, particularly with solid foods of different composition.

A major use of microwaves in the food industry is the tempering and thawing of frozen foods, especially meat, fish, butter and fruit.
Process of microwaving the food

Losses of tocopherol during food processing

Naturally occurring vitamin E comprises tocopherols and tocotrienols. Processing and storage of foods can result in substantial tocopherol losses. Cooking of porridges of rolled oats and rye meal implies only minor effects on their tocopherol and tocotrienols contents.

Studies of alpha-tocopherol in UHT processed milk suggest that the processing conditions affect the subsequent losses, but that in all cases increased storage temperature led to increased rate of loss.

There was a loss of tocopherol reported in the study of potato chips. After only two weeks’ storage of the chips at room temperature, nearly half of the tocopherol was lost.

The losses were only slightly smaller during storage at freezer temperature.

Deep fat frying of fresh vegetable oil causes losses of about 10% but storage of fried foods, even at low temperature, may cause large losses.  The low content of alpha-tocopherol in frozen foods is surprising and indicates serious degradation even at 12 °C.

Boling of vegetables in water for up 30 minutes results in only minor losses of tocopherol.

Baking of white bread (200 °C, 30 minutes) destroyed of about 5% of the tocopherol in the crumb.

Tocopherol losses during microwave cooking are mainly caused by the effect of high temperature and not by microwaves as such. When sunflower oil was subjected to microwaves discontinuously for 120 min at two constant temperatures: namely 170 °C and less than 40 °C, tocopherol losses were 72% and 21%, respectively.
Losses of tocopherol during food processing 

Processing of fudge

The name fudge covers a wide range of products which are basically toffee formulation but in which sugar crystal has been developed during processing.

Fudge consists of oil, water and milk ingredients.  Normally fudge contains more sugar and milk than a toffee, but composition can vary between very wide limits. The hardness and texture of the final fudge are mainly determined by the water content, which in turn is controlled by the boiling temperature. The higher the temperature, the lower the water content and it will harder the final product.

Vanilla fudge packaging

Fudge is produced by boiling a caramel batch to 120 – 123 ° C, cooling it to about 105 ° C. It is then cats or spread on tables to allow crystallization to develop.

Fudge is a grained product, and some means of graining is required. This can be done by removing part of the cooked batch, cooling it and working it until crystallises, when it is added back to the remainder of the hot batch and thoroughly mixed in.

Whilst this is feasible it is not usual and use of fondant to provide seed crystal is almost universal. Usually about 5% is required but increasing the quality will produce finer crustal and a more plastic product.

Chocolate fudge brownies with walnuts

In fudge applications, the fat works as a smoothing and shortening agent making the product less sticky.

Another very important function of the fat is as a flavour carrier which means that it needs to have very good flavor and flavour stability.
Processing of fudge

History of Cooking

History of Cooking
Perhaps by accident, although anthropologists are still arguing about this. One theory is that an out of control fire burned down a hut and accidently cooked some pigs. People wandered in, tried the cooked meat and liked it.

Another theory is that a forest fire first roasted meat; still others think that cooking was a more deliberate, controlled act by humans. In any case, now there were more options than raw bar and tartare.

It was cooking but how about cuisine? Cuisine can be defined a self conscious tradition of cooking and eating, with a set of attitude about food and its place in the life of man.

So cuisine requires not just a style of cooking but an awareness about how the food is prepared and consumed.

It must also a wide variety of ingredients, more than are locally available and cooks and diners willing to experiments which means they are not constricted by tradition.

Since early humans were still eating to survive and had no control over their food supply, it was not cuisine.

Nobody knows exactly how people mastered fire and started cooking their food, we only know when - between 500,000 and one million years ago.

Roasting over an open fire probably the first cooking method. Pit roasting – putting food in a pit with burning embers and covering it - might have come next.

Then spit roasting, when hunters came home with the animal already on a spear and decided to cook it by hanging it over the fire and turning it.

With sharp tools, meat could be cut into smaller pieces to make it cook faster. Food could be boiled large mollusk or turtle shells where they were available, or even in animal skins, but pots were not invented until around 10,000 BC and there were no sturdy clay boiling pits until about 5000 BC.

Cooking in such vessels would probably have produced bacterial contamination, since there was no soap and no effective way to clean them.
History of Cooking

Ready to Eat Cereals

Ready to Eat Cereals
Ready to eat cereals are processed grain formulations suitable for human consumption without further cooking in the home. They are relatively shelf-stable, lightweight, and convenient to ship and store. There are made primarily from corn, wheat, oats or rice, in about that of order of the quantities produced, usually with added flavor ad fortifying ingredients.

Hot cereals, on the other hand, are made primarily from oats or wheat; those made from corn or rice are of minor importance, being produced in relatively small quantities. The original hot cereals required cooking in the home before they were ready for consumption, but now some varieties are preprocessed so that they are ready for consumption with the addition of either hot water or milk to the cereal in the bowl.

The processing of ready to eat cereals typically involves first cooking the grain with flavor material and sweeteners. Sometimes the more heat stable nutritional fortifying agents are added before cooking, Two general cooking methods are employed in the industry today – direct steam injection into the grain mass in rotating batch vessel, and continuous extrusion cooking , with the latter very much on the increase in recent decades.
Ready to Eat Cereals