Are citric acid and ascorbic acid the same thing? * When you drizzled a little lemon juice over some cut apples, you might have said to yourself, “thank heavens for citric acid and its wonderful ability to keep fruits and vegetables from turning brown. Vitamin C is a great thing! ” Assuming your high-school chemistry student was raiding the refrigerator for the 11th time that day and that he was listening to you (a preposterous assumption), he would simply have rolled his eyes and come up with one more reason to mock you. . The fact is, there is citric acid and ascorbic acid in lemon juice, but they are not the same thing, and it is the ascorbic acid that keeps the fruits and vegetables from turning brown. Indeed, ascorbic acid is the more versatile and essential of the two acids. Ascorbic acid, or vitamin C, has a chemical make-up of C6H8O6. While it is found in citrus fruits, billygoat plums, rose hips, blackcurrants, guavas, kiwi fruits, broccoli, and Brussels sprouts are much better sources.
Most animals can also produce it themselves, although most fish, some birds, all guinea pigs, and some primates — and man — cannot, and so must get it from other sources. In cooking, besides keeping cut fruits and vegetables from turning brown, ascorbic acid promotes the growth of yeast, and so is also often added as an enhancer to bread dough. In commercial food processing it is used as an antioxidant preservative. Citric acid has one more oxygen atom than ascorbic acid; its formula is C6H8O7.
It occurs naturally in citrus fruits and some other fruits and vegetables. It can also be synthetically produced from sugar…Citric acid is used commercially to enhance the tartness in fruit-flavored candy and in soft drinks. It is also added to some ice creams to keep fat globules from coagulating. Some bakers use it in sourdough bread to produce an especially assertive tang. Pickling……Pickling is a global culinary art. If you were to go on an international food-tasting tour, you’d find pickled foods just about everywhere.
You might sample kosher cucumber pickles in New York City, chutneys in India, kimchi in Korea, miso pickles in Japan, salted duck eggs in China, pickled herring in Scandinavia, corned beef in Ireland, salsas in Mexico, pickled pigs feet in the southern United States, and much, much more…… What makes a pickle a pickle? On a most general level, pickles are foods soaked in solutions that help prevent spoilage. …. There are two basic categories of pickles. The first type includes pickles preserved in vinegar, a strong acid in which few acteria can survive. Most of the bottled kosher cucumber pickles available in the supermarket are preserved in vinegar. …. The other category includes pickles soaked in a salt brine to encourages fermentation—the growth of “good” bacteria that make a food less vulnerable to “bad” spoilage-causing bacteria. Common examples of fermented pickles include kimchi and many cucumber dill pickles….. Pickling is not only an international food-preservation technique, it’s also an ancient one.
For thousands of years, our ancestors have explored ways to pickle foods, following an instinct to secure surplus food supplies for long winters, famine, and other times of need. Historians know, for instance, that over two thousand years ago, workers building the Great Wall of China ate sauerkraut, a kind of fermented cabbage. …,But pickling foods does much more than simply preserve them. It can also change their taste and texture in a profusion of interesting—and yummy—ways. It’s no surprise that cultures across the globe enjoy such an assortment of pickled foods, as you would discover on your international food expedition.
In fact, food experts say, the evolution of diverse pickled foods in different cultures has contributed to unique cultural food preferences, such as spicy sour tastes in Southeast Asia and acidic flavors in eastern Europe. meat…Meat is mostly the muscle tissue of an animal. Most animal muscle is roughly 75% water, 20% protein, and 5% fat, carbohydrates, and assorted proteins. Muscles are made of bundles of cells called fibers…. Each cell is crammed with filaments made of two proteins: actin and myosin. …In a live animal, these protein filaments make muscles contract and relax.
Both actions require enormous amounts of energy, which they get from the energy-carrying molecule ATP (adenosine triphosphate). The most efficient generation of ATP requires oxygen, which muscles get from circulating blood. After an animal is slaughtered, blood circulation stops, and muscles exhaust their oxygen supply. Muscle can no longer use oxygen to generate ATP and turn to anaerobic glycolysis, a process that breaks down sugar without oxygen, to generate ATP from glycogen, a sugar stored in muscle. …The breakdown of glycogen produces enough energy to contract the muscles, and also produces lactic acid.
With no blood flow to carry the lactic acid away, the acid builds up in the muscle tissue. If the acid content is too high, the meat loses its water-binding ability and becomes pale and watery. If the acid is too low, the meat will be tough and dry. .. Lactic acid buildup also releases calcium, which causes muscle contraction. As glycogen supplies are depleted, ATP regeneration stops, and the actin and myosin remain locked in a permanent contraction called rigor mortis. Freezing the carcass too soon after death keeps the proteins all bunched together, resulting in very tough meat.
Aging allows enzymes in the muscle cells to break down the overlapping proteins, which makes the meat tender… Without ATP, actin and myosin remain locked in a permanent contraction called rigor mortis. .. Individual protein molecules in raw meat are wound-up in coils, which are formed and held together by bonds. When meat is heated, the bonds break and the protein molecule unwinds. Heat also shrinks the muscle fibers both in diameter and in length as water is squeezed out and the protein molecules recombine, or coagulate.
Because the natural structure of the protein changes, this process of breaking, unwinding, and coagulating is called denaturing. The Best-to-Worst Ways to Cook Your Food You take great care in choosing the right foods for your family to eat, but did you know that the way they’re prepared can have a large impact on their nutritional value? Whereas some cooking methods will preserve the food’s nutrients and flavor, others can actually diminish nutrient content and create harmful substances within your food… What about the microwave?
While some believe microwaving is a fast way to cook food without a lot of extra oils, others believe it can change the chemical structure of the food in unknown, potentially negative, ways, while reducing fragile nutrients. It is always preferable to cook foods at lower temperatures than higher temperatures, not only because the nutrients are better preserved but also because the oils that you cook your food with — particularly vegetable oils like soybean, corn and canola — are easily damaged (oxidized) by the heat, posing health risks… Fortunately, there are many cooking methods out there that are good for your food and good-tasting.
Here we’ve outlined some of the most popular cooking methods, starting with the healthiest methods and ending up with the worst. 1. Eat Your Foods Raw.. Well, it’s not exactly a cooking method, but it is a very healthy way to consume many of your favorite foods. Raw foods, advocates say, are higher in vitamins and nutrients, which are destroyed by cooking. Eating raw may seem extreme, but you can actually prepare some pretty tasty dishes if you know what foods to combine. 2. Steaming…Steaming is cooking food in an environment where the surrounding air has high moisture content.
Regarded as one of the healthiest methods of cooking, steaming is growing in popularity because no fats or oils are used during the cooking process. Steaming retains most nutrients during cooking processes and the most natural flavour out of all the cooking……methods. Steaming can be done in a microwave or on the stove top with metal or bamboo steamers. Simply put a little water in a pot, put in a steamer basket or colander, and add your food. As the water boils, the steam will gently cook your food.
Be sure not to cook your food for too long (veggies should still be brightly colored and slightly crunchy when they’re done), and you can also add some spices to the water to flavor the foods as they steam. This method works especially well for fragile vegetables like leafy greens and fish. 3. Poaching…. Poaching is also cooking food that is completely submerged in water, milk or a flavoured liquid. Different to boiling and simmering, poaching is done at 93°C/119°F to 95°C/203°F where there is no movement in the liquid. The most delicate foods such as eggs (out of shell), soft fruits, chicken breast and some fish are usually poached.
You can poach chicken, eggs and other foods by simmering them in a little bit of water or broth on your stovetop. Use a covered pan and take the foods off the heat when they’re tender. For this reason, it is important to keep the heat low and to keep the poaching time to a bare minimum, which will also preserve the flavour of the food. 4. Baking/Roasting…. Baking in your oven is a perfectly healthy way to cook, though it’s preferable to use a lower temperature and a longer cooking time than a higher temperature to cook the food more quickly (roasting is typically done at a higher temperature).
You can bake meat, fish, poultry, veggies, bread, fruit and anything else. To keep in some of the moisture, try keeping your baking dish covered……Raw Gourmet Meals in Five Minutes is the perfect cooking companion for anyone who wants to get more fresh, healthy and great-tasting foods into their diet — but doesn’t have a lot of time to do it. 5. Stir-Frying…. Stir-frying is a fast, healthy way to cook. Chop your meat and veggies into small, uniform pieces, add a little oil or broth to a pan or wok, then stir the foods until they’re just cooked through (add meat, which takes longer to cook, before the veggies).
To preserve the nutrients in the veggies, cook them only slightly. 6. Braising…Braising is similar to stewing, but the food that is being cooked is only half covered in liquid. With braising, the vessel where the food is being cooked is covered with a tight lid and put in the oven. This is where the cooking process takes place. The heat is encasing the pot and giving it even heat from all over. The braising temperature for meat is usually about 180°C/355°F to 200°C/390°F. For vegetables it’s between 140°C/285°F to 160°C/320°F. Cuts of meat with high sinew and muscle content such as lamb shanks and shoulders are usually used.
When you braise a piece of meat or fish, you brown it slightly in a pan, then cover it with a small amount of liquid such as broth. The pan is covered, and the food is left to slowly and gently finish cooking. After the food is removed, the leftover juices can be used to make a flavorful sauce. 7. Boiling…boiling is the transfer of heat to food that is totally immersed in water, milk or a seasoned stock. Boiling is done at 100°C/212°F. Not all foods are suitable for boiling. High temperature can sometimes toughen up meat. Therefore a long and slow simmering on a low heat maybe required to tenderize the meat.
Rapid boiling and simmering can break up some delicate foods such as brains, berries and fish leaving them unappealing to eat. The foods that are more suitable for boiling are starchy items such as noodles or rice. Root vegetables, like potato and carrots are also good for boiling due to their tougher texture. However, delicate foods like fish are not recommended for boiling as they will fall apart. Boiled foods are healthy in that no harmful substances form when using this cooking method. However, there is some concern that nutrients may be lost when foods are boiled, and they may become overcooked.
Steaming is a preferable cooking method to boiling. Want a break from the stove? Try a raw smoothie for breakfast or a snack. All you need is a blender, some fresh or frozen fruit, and, if you like, some kefir, yogurt or whey protein powder. 8. Sauteing…. Sauteing is a method of cooking food, that uses a small amount of fat in a shallow pan over relatively high heat. Ingredients are usually cut into pieces or thinly sliced to facilitate fast cooking. The primary mode of heat transfer during sauteing is conduction between the pan and the food being cooked. Food that is sauteed is browned while preserving its texture, moisture and flavor.
If meat, chicken, or fish is sauteed, the saute is often finished by deglazing the pan’s residue to make a sauce. Sauteing (cooking foods in a small amount of oil on your stovetop) is an acceptable form of cooking, although it does pose the problem of oxidizing oils. To avoid this, replace the oil with some broth instead and don’t turn the heat up too high. 9. Grilling and Broiling…. Many people love to grill their foods, however there are some potential problems to be aware of. Barbecue grill smoke contains cancer-causing chemicals known as polycyclic aromatic hydrocarbons.
Meanwhile, heterocyclic amines form when food is cooked at a high temperature, such as those used in grilling and broiling. The chemicals have been linked to cancer. Advanced glycation end (AGEs) products are also produced when meats are cooked at high temperatures. AGEs, according to researchers at Mount Sinai School of Medicine in New York, build up in your body over time leading to oxidative stress, inflammation and an increased risk of heart disease, diabetes and kidney disease. 10. Frying…Frying foods is the absolute worst way to cook your foods. The high temperatures produce cancer-causing heterocyclic amines, along with AGEs.
Meanwhile, frying exposes your foods to large amounts of oxidized (rancid) vegetable oils, which then soak into your food and wreak havoc in your body. You should avoid frying your foods and use the cooking methods higher up on this page instead. FOOD & FOOD GROUPS…Food is the basic necessity of man. It is a mixture of different nutrients such as carbohydrate, protein, fat, vitamins and minerals. These nutrients are essential for growth, development and maintenance of good health throughout life. They also play a vital role in meeting the special needs of pregnant and lactating women and patients recovering from illness.
Functions of Food
Food may be classified according to their functions in the body. Physiological functions of food i. Energy yielding foods Foods rich in carbohydrates and fats are called energy yielding foods. They provide energy to sustain the involuntary processes essential for continuance of life, to carry out various professional, household and recreational activities and to convert food ingested into usable nutrients in the body. The energy needed is supplied by the oxidation of foods consumed. Cereals, roots and tubers, dried fruits, oils, butter and ghee are all good sources of energy. ii. Body building foods
Foods rich in protein are called body building foods. Milk, meat, eggs and fish are rich in proteins of high quality. Pulses and nuts are good sources of protein but the protein is not of high quality. These foods help to maintain life and promote growth. They also supply energy. iii. Protective and Regulatory foods Foods rich in protein, minerals and vitamins are known as protective and regulatory foods. They are essential for health and regulate activities such as maintenance of body temperature, muscle contraction, control of water balance, clotting of blood, removal of waste products from the body and maintaining heartbeat.
Milk, egg, liver, fruits and vegetables are protective foods. Social functions of food Food has always been the central part of our community, social, cultural and religious life. It has been an expression of love, friendship and happiness at religious, social and family get-togethers. Psychological functions of food In addition to satisfying physical and social needs, foods also satisfy certain emotional needs of human beings. These include a sense of security, love and acceptance. For example, preparation of delicious foods for family members is a token of love and affection.
Cooking
Food preparation helps in combining food ingredients in various ways with delicate flavours, textures and colour which appeal to thesenses. Food has to be pleasing in appearance and taste so that it is consumed. Understanding food behavior in scientific terms helps in choosing best method of cooking. Food preparation is an important step in meeting the nutritional needs of the family. Foods like fruits, vegetables and nuts are eaten raw but most of the foods are cooked to bring about desirable changes. The process of subjecting foods to the action of heat is termed as cooking.
Cooking by Dry Heat
- Baking Roasting
Cooking by Moist Heat
- Boiling Stewing Steaming Frying
Objectives of Cooking
Improves the taste and food quality Cooking improves natural flavor and texture of food. For example roasting groundnuts, frying onions and papads, cooking rice and roasting coffee seeds improve the flavor. Cooking meat with spices, rice with spices in making pulav, frying cashewnuts in ghee, addition of turmeric, curry leaves, pepper in pongal, blend flavor with one another during cooking. Too much of cooking lowers the flavor as flavouring compounds are volatile.
Over – cooked pulav does not taste as good as well cooked pulav. Destruction of microorganisms Microorganisms are present everywhere and some are useful in making curd, cheese and bread. Some are harmful and cause infections or produce toxins, e. g. clostridium botulism and salmonella. Some moulds produce toxins. Aspergillums in groundnuts, cereals and spices. This aflotoxin is a health hazard. One of the most important methods of protection of food against harmful microorganism is by the application of heat.
Cooking food to the required temperature for a required length of time can destroy all harmful microorganisms in food. E. g. Pasteurized milk. Tapeworm or its larvae which infest pork can be killed by proper application of heat. By cooking, food is made for consumption. Improves digestibility Cooking softens the connective tissues of meat and the coarse fibres of cereals, Pulses and vegetables so that the digestive period is shortened and gastrointestinal tract is less subjected to irritation. Cooking improves the texture hence it becomes more chewable.
Cooking also bursts the starch granules of pulses and cereals so that the starch digestion is easier, rapid and complete. When dry heat is applied to starches they are converted to easily digestible dextrins. Cooking increases the access to enzymes and improves digestibility. Increases variety By cooking, same food can be made into different dishes. For example rice can be made into plain, pulav, lemon rice, biryani or combination with pulses and idli. Wheat can be made into chapattis, puri , paratha or halwa. Increases consumption of food Cooking improves the texture and makes the food chewable.
Improvement in texture and flavour by cooking increases consumption of food to meet our nutritional requirement. Increases availability of food Raw egg contains avidin which binds biotin making biotin unavailable to the body. By cooking, avidin gets denatured & biotin is available to the body Trypsin inhibitors present in soyabean and duck egg get denatured on cooking and availability of protein is improved. Toxic substances from kesari dhal can also be removed by boiling it and throwing away the water. Cooking increase the quality protein by making some amino acids available to the body.
Concentrates nutrients This may be due to removal of moisture or using combination of foods or due to cooking procedures. E. g. sweets. Limitations of cooking Thiamine, which is heat sensitive, may be lost during cooking. Water soluble nutrients are leached into the water during cooking. Vitamin A and C content may be reduced due to oxidation and heat. Quality of protein may be reduced due to destruction of certain amino acids during cooking e. g. bread crust has less quality of protein compared to the inside portion.
Nutritional Effects of Food Processing
An overview of some of the effects that cooking and other food processing methods have on the nutritional value of foods is given below.
- Freezing, Drying, Cooking, and Reheating
- Consuming Raw Foods
Grilling Meats Freezing, Drying, Cooking, and Reheating Nearly every food preparation process reduces the amount of nutrients in food. In particular, processes that expose foods to high levels of heat, light, and/or oxygen cause the greatest nutrient loss. Nutrients can also be “washed out” of foods by fluids that are introduced during a cooking process.
For example, boiling a potato can cause much of the potato’s B and C vitamins to migrate to the boiling water. You’ll still benefit from those nutrients if you consume the liquid (i. e. if the potato and water are being turned into potato soup), but not if you throw away the liquid. Similar losses also occur when you broil, roast, or fry in oil, and then drain off the drippings. The table below compares the typical maximum nutrient losses for common food processing methods. This table is included as a general guide only. Actual losses will depend on many different factors, including type of food and cooking time and temperature..
