Foods that are high in proteins Proteins derive their name from the Greek word proteos. of “prime importance.” The body can manufacture most of the necessary carbohydrates (except fiber) and lipids (except a few essential fatty acids) it needs, but when it comes to protein, the body can synthesize only about half of the compounds […]
Category: Chemistry of Food Composition
You are what you eat..! Food and people are composed of the same chemical materials, and there was a time when people serves as nourishment to other animals in the food chain. All food, including people, consist of six basic nutrient groups: water, carbohydrates, lipids, proteins, vitamins, and minerals. Food provide varying amounts of nutrients. Milk, for example is 80 percent water, meats serve as primary sources of protein, potatoes and grains are rich in carbohydrates, and nuts are almost all fat. Most food contain a combination of the six major nutrient groups.
Since people literally are what they eat, the main purpose of eating and drinking is to replace those nutrients used up in the body’s maintenance, repair and growth, and to obtain the calories necessary for energy. Calories are like fuel to the body, as gas is fuel to a car. Unlike cars, however, living organisms never shut down, even during sleep. Over half the calories used by the body, about 60 percent, are used soley for vital life functions such as maintaining body temperature, respiration and heartbeat. Another 10 percent is used for digesting and absorbing the nutrient from food, and the remaining 30 percent, depending on the person, is used for physical activity.
Phospholipids Phospholipids are similar to triglycerides in structure in that fatty acids are attached to the glycerol molecule. The difference is that one of the fatty acids is replaced by a compound containing phosphorus, which makes the phospholipid soluble in water, while its fatty acid components are soluble in fat. The dual nature of phospholipids […]
Water is the simplest of all the nutrients, yet it is the most important. Without it, life could not exist. Life probably began in water billions of years ago, and it is still essential at every stage of growth and development. Water brings to each living cell the ingredients that it requires and carries away […]
Freezing Point Winter in many parts of the world brings freezing temperatures. The temperatures of winter can turn water into ice when its freezing point is reached. The lower temperature decreases water’s kinetic energy, or the energy associated with motion, which slows the movement of the water molecules until they finally set into a compact […]
Triglycerides About 95 percent of all lipids are triglycerides, which consist of three (“tri”) fatty acids attached to a glycerol molecule. Two fatty acids linked to the glycerol molecule, form a diglyceride, while one fatty acid linked to glycerol is a monoglyceride. The fatty acids on the glycerol can be identical (simple triglyceride) or different […]
Polysaccharides (Fiber) Fiber, also known as roughage or bulk, describes a group of indigestible polysaccharides. Unlike starch, the sugar units in fibers are held together by bonds the human digestive enzymes cannot break down. Most fibers, therefore, pass through the human body without providing energy. Fiber is found only in foods of plant origin, especially […]
Polisaccharides (Starch) Starch, fiber, and glycogen are the polysaccharides most commonly found in foods. Starch The glucose derived from photosynthesis in plants is stored as starch. As a plant matures, it not only provides energy for its own needs, but also stores energy for future use in starch granules. Microscopic starch granules are found in […]
Foods High in Vitamins and Minerals Most foods contain some vitamins and minerals. Vitamins can be categorized into two major groups: fat-soluble (A, D, E, and K) or water-soluble (B complex and vitamin C). Minerals may be termed either macro or micro. Meats are good sources of B vitamins, iron (Fe), and zinc (Zn). Dairy […]
Functions of Proteins in Food The proteins in foods allow certain reactions to occur during preparation: hydration, denaturation/coagulation, enzymatic reactions, buffering, and browning. Hydration The ability of proteins to dissolve in and attract water, a process called hydration, allows them to play several important roles in foods. One of these is the capability to form […]
Functions of Vitamins and Minerals in Food Vitamins and minerals regulate metabolic functions. Because of the vital role these compounds play in the body’s processes, many foods are now enriched or fortified with additional vitamins and minerals. During processing and preparation, foods such as wheat and rice may lose some of their vitamin or mineral […]