1. Emulsifier
An emulsion is a dispersion or suspension of a liquid in a liquid On the other hand, the molecular data of the two liquids do not dissolve each other but are mutually antagonistic.
In general, emulsions are unstable, that is, they can break, or in other words, fat and water will separate, depending on the environmental conditions. To stabilize the emulsion system, an emulsifier is usually added to it.
Substances that can maintain the dispersion of fat in water or vice versa are called emulsifiers. For example, in lettuce and mayonnaise sauce, fat and water will separate without any emulsifier added. The emulsion can be maintained by adding egg yolk as an emulsifier. The most important substances in egg yolks that can maintain the emulsion are phospholipids, among which lecithin is the most important.
Lecithin has a structure like fat but contains phosphoric acid. Lecithin has polar and nonpolar groups. The polar group contained in the phosphate ester is hydrophilic and has a tendency to dissolve in water, while the nonpolar group contained in the fatty acid ester is lipophilic, which has a tendency to dissolve in fat or oil.
Lecithin and other phospholipids are found in animal bodies, namely in eggs, blood, and in-plant fabrics. Monoglycerides and diglycerides are also effective as emulsifiers.
2. Organic Acids
Many organic acids are found in agricultural food, They are generally the product of Krebs cycle metabolism. Fruits contain high levels of acids such as citric acid, which is the main organic acid in oranges and lemons, malic acid in apples, and tartaric acid in grapes. The presence of these acids causes the fruit to have a sour taste, distinctive taste, and slow to rot. Apart from being the result of the physiological process of the material itself, acid can also be produced intentionally through the fermentation of certain foodstuffs by certain microbes (yeasts and bacteria), giving rise to a distinctive taste. For example, fermenting mustard or cabbage leaves produces lactic acid, fermenting apples first produces alcohol, then acetic acid or vinegar. In making cheese, a starter of certain bacteria is used which is added to milk to produce lactic acid, so that it can precipitate milk proteins to form curd.
3. Oxidants and Antioxidants
Some foodstuffs tend to bind oxygen from the air. This is especially true for foods that contain fat or oil. If left too long in the open air will cause oxidation of the material, resulting in damage called rancidity.
Some vitamins found in foodstuffs such as carotene (provitamin A) and ascorbic acid (vitamin C) are examples of materials that are sensitive to oxidation.
Oxygen in the air at a level of about 20% is an oxidant that is always present around food. This oxygen can be reduced by vacuum packaging or replaced with nitrogen. Certain metal ions such as copper ions and iron ions are oxidation catalysts. To avoid this oxidation, copper and iron in food processing are replaced with stainless steel. Natural foodstuffs also contain antioxidants, so they can withstand oxidative damage. Natural antioxidants found in foodstuffs include lecithin, vitamin E, and several amino acids containing sulfur (-SH group).
4. Enzyme
There are still metabolic processes in most of the materials agricultural produce that has been harvested or picked. The process shows that there is still life, which is due to the presence of active enzymes.
Enzymes are biological catalysts that can assist in various biochemical reactions. For example, bananas that are still unripe when picked can ripen, sweet potatoes that are stored can be sweeter than freshly harvested, amylase found in saliva can digest starch in the mouth, pepsin in stomach juices can digest protein and lipase in the pancreas. can break down fat. There are approximately 100 kinds of enzymes in bacteria, yeasts, molds, plants, and animals. After plants are harvested or animals are slaughtered, most of the enzymes are still active in some chemical reactions.
After harvesting, the enzymes will continue the ripening process, unless the enzymes are inactivated by heat, by chemical reactions, or by other treatments. If the enzyme is not inactivated, it is likely that the process of spoilage will occur.
Enzymes can cause changes in taste, color, texture, and other properties of food ingredients. The heating process in food is not only intended to kill microbes but also to inactivate enzymes so that food remains stable during storage.
Enzymes can also be extracted from biological materials and can also be purified. Enzymes in their pure form can be added to foodstuffs to break down starches, tenderize meat, clarify wine, coagulate milk proteins, or other changes.
5. Pigments and Colors
The color of foodstuffs can be caused by several sources, and one of the most important is the pigment in plant or animal materials. For example, chlorophyll gives lettuce or chickpea its green color, carotenes give carrots and corn their orange color, lycopene gives tomatoes and watermelon their red color, anthocyanins give beets and coffee their purple color, and myoglobin gives their coloration. red to the flesh.
Natural pigments usually undergo chemical changes, such as those that occur in ripening fruit or curing meat. Pigments are also very sensitive to chemical and physical changes during processing, especially heat which greatly affects food pigments. In addition, mechanical blows and grinding cause pale discoloration. This is because most of the plant and animal pigments are collected in woven cells and body pigments, such as chlorophyll contained in chloroplasts, if these cells rupture due to grinding or blowing, the pigment will come out and some will be damaged or damaged. oxidized on contact with air.
Not all colors are caused by natural pigments from plants or animals. Color can also be caused by the influence of other factors, for example, the caramelization of sugar causes a dark brown color. Some examples that include caramelization are the dark color (dark brown) of cane sugar due to heating, the color of toasted bread, and the brown color of confectionery caramel.
Another cause of discoloration is a chemical reaction between sugars and amino acids and proteins known as the browning reaction or Maillard reaction. In this state, the amino groups of the protein react with the aldehyde or ketone groups of the reducing sugars to produce a brown color, for example, the dark color of powdered milk that has been stored for too long.
The browning process as described above is called a non-enzymatic browning reaction. In addition, enzymatic browning can also occur, for example, a dark color on the surface of the cut from apples or salak and brown color from tea derived from tannins.
Food color is also caused by the addition of natural or artificial dyes, for example adding turmeric to tofu, adding pandan leaf extract to the banana cake.
6. Taste
Changes that occur in the taste of foodstuffs are usually more complex than is the case with the color of foodstuffs. For example, coffee has 200 known components that cause taste and aroma, although each is in very low concentrations.
These organic substances are very sensitive to air, heat, and their interactions with one another. The taste and aroma of the coffee, milk, meat, and most other foodstuffs usually undergo changes (unstable) during handling, processing, and storage.
Changes that occur in the taste of foodstuffs are more complex than those that occur in the color of foodstuffs. There is an exception that the taste actually develops during the processing of taco, soy sauce, cheese ripening, brem storage, shrimp paste fermentation, and fish.
The taste components can be separated by a gas chromatograph. In this way, the aroma components will be separated from each other based on their evaporation power through a column with a certain absorbent. Each component will give a certain peak on the chromatogram paper (recording chart) and can then be identified. Subjectively the taste can be investigated by organoleptic test by a "taste panel".
7. Vitamin
Vitamins are important components in food, although there are small amounts. Vitamins can be grouped into 2 groups, namely:
a. Fat-soluble vitamins are vitamins A, D, E, K.
b. Water-soluble vitamins are vitamin C and the B complex group of vitamins.
Vitamin A is generally found in animal products such as meat, milk, and eggs. Vegetable products generally do not contain vitamin A but contain a form of provitamin A known as beta-carotene, for example in tomatoes, sweet potatoes, carrots, and green vegetables. Lack of vitamin A will cause blindness in chickens, abnormal growth in childhood, abnormalities in the eye membranes and epithelial membranes.
Vitamin D3 is formed in the subcutaneous tissue of animals and humans, due to the conversion of 7-dehydrocholesterol by ultraviolet rays from sunlight. Ergosterol irradiation can produce vitamin D2 which can be used as an addition to vitamin D in milk and other foods. Vitamin D is found in liver, fish oil, dairy products, and eggs.
Children need 400 IU of vitamin D per day, IU (International Units) is equivalent to 0.025 gamma vitamin D2. Vitamin D deficiency can cause bone growth abnormalities in children.
Vitamin E is an anti-infertility factor for mice, important for the formation and health of animal bone tissue. In general, humans rarely lack vitamin E. Vitamin E is a powerful antioxidant and functions in preventing the excessive formation of peroxides in tissues. An important source of vitamin E is certain vegetable oils.
In general, vitamin C is found in many plant materials. Foodstuffs that are sources of vitamin C are oranges, tomatoes, and green chilies. Both potatoes and milk, whole grains, and meat contain little vitamin C. Vitamin C at high temperatures is easily damaged by oxidation. This vitamin is easily lost during processing and storage. Lack of vitamin C causes brittleness of the capillary walls, bleeding gums, easy tooth loss, and bone joint disease.
The group of B complex vitamins includes thiamin, riboflavin, niacin, pyridoxine, pantothenic acid, folic acid, vitamin B12, biotin and choline. All vitamins from this group are usually found in the same foodstuffs such as liver, yeast, and grain bran. All vitamins of this group are needed for smooth metabolism and some are useful for enzyme activity.
8. Mineral
Most foodstuffs, approximately 96% consist of organic matter and water, the rest consists of mineral elements. Mineral elements are also known as inorganic substances or ash content. Although many of the mineral elements are known for their function in animal feed, there have not been many similar studies conducted in humans.
Until now it has been known that there are fourteen mineral elements needed by humans, in order to have good growth and health. Important minerals are sodium, chlorine, calcium, phosphorus, magnesium, and sulfur. These elements are present in the body in large enough quantities, therefore they are called macroelements or macro minerals. Other mineral elements are present in small amounts and are called micro minerals or trace elements, such as iron, iodine, manganese, copper, zinc, cobalt, and fluorine. The other three elements, namely aluminum, boron, and vanadium, are found in animal tissues, but it is not known for certain whether these elements have specific functions in the human body.
Generally, minerals are not affected by the processing. Calcium is needed by the body because a lack of calcium can cause abnormalities in bones and teeth, it is also important in blood clotting and enzyme activity. Phosphorus is important for controlling metabolic reactions that produce energy, as well as for controlling the acid and alkaline balance in the blood. Iron in the body is partly located in red blood cells as heme, a pigment that contains an iron atom in the nucleus. There are four hemes in a hemoglobin molecule. Iron is found in muscle cells, especially in myoglobin. In contrast to hemoglobin, myoglobin consists of one heme pigment for each protein.
CLASSIFICATION OF FOOD INGREDIENTS
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