Yogurt A-Z Directory

Acidophilus

One of several bacteria in the genus Lactobacillus. It is commonly used commercially together with Streptococcus thermophilus and Lactobacillus bulgaricus in the production of yogurt. Lactobacillus acidophilus gets its name from lacto- meaning milk, -bacillus meaning rod-like in shape, and acidophilus meaning acid-loving. This bacterium thrives in more acidic environments than most microorganisms (pH 4-5 or lower) and grow best at 45 degrees Celsius.

L. acidophilus occurs naturally in a variety of foods, including dairy, grain, meat, and fish. It is also present in human (and animal) intestines and mouths. L. acidophilus (and all lactic acid bacteria) absorb lactose and metabolize it into lactic acid. Like many bacteria, L. acidophilus can be killed by excess heat, moisture, or direct sunlight. L. acidophilus is considered a probiotic or "friendly" bacterium.

The breakdown of nutrients by L. acidophilus produces lactic acid, hydrogen peroxide, and other byproducts that make the environment hostile for undesired organisms. During digestion, L. acidophilus also assists in the production of niacin, folic acid, and pyridoxine. Studies have also shown L. acidophilus can assist in bile deconjugation, separating amino acids from bile acids, which can then be recycled by the body.

Some research has indicated L. acidophilus may provide additional health benefits, including improved gastrointestinal function, a boosted immune system, and a decrease in the frequency of yeast infections. Some people report L. acidophilus provides relief from indigestion and diarrhea.

A University of Nebraska study found that feed supplemented with L. acidophilus and fed to cattle resulted in a 61% reduction of Escherichia coli 0157:H7. Research at Oklahoma State University has indicated L. acidophilus may be helpful reducing serum cholesterol levels. Studies at the University of Kentucky indicated a treatment with L. acidophilus resulted in a 10 to 12% reduced risk of coronary heart disease in persons with high blood serum cholesterol levels.

Allergies

Research indicates that one of the ways probiotic cultures in yogurt (in particular) might help reduce allergies is by restoring normal function to your intestinal mucosa. This then can help prevent allergens from making it through the mucosal barrier.

Antibiotics

An antibiotic is a drug that kills or slows the growth of bacteria. They have no effect against viruses, fungi, or parasites. Antibiotics are one class of antimicrobials, a larger group which also includes anti-viral, anti-fungal, and anti-parasitic drugs. They are relatively harmless to the host, and therefore can be used to treat infections.

The term, coined by Selman Waksman, originally described only those formulations derived from living organisms, in contrast to "chemotherapeutic agents", which are purely synthetic. Nowadays the term "antibiotic" is also applied to synthetic antimicrobials, such as the sulfa drugs. Antibiotics are generally small molecules with a molecular weight less than 2000. They are not enzymes.

Some antibiotics have been derived from mold, for example the penicillin class. Unlike previous treatments for infections, which included poisons such as strychnine and arsenic, antibiotics were labelled "magic bullets": drugs which targeted disease without harming the host. Conventional antibiotics are not effective in viral, fungal and other nonbacterial infections, and individual antibiotics vary widely in their effectiveness on various types of bacteria. Antibiotics can be categorised based on their target specificity: 'narrow-spectrum' antibiotics target particular types of bacteria, such as Gram-negative or Gram-positive bacteria, while 'wide-spectrum' antibiotics affect a larger range of bacteria.

The effectiveness of individual antibiotics varies with the location of the infection, the ability of the antibiotic to reach the site of infection, and the ability of the bacteria to resist or inactivate the antibiotic. Some antibiotics actually kill the bacteria (bactericidal), whereas others merely prevent the bacteria from multiplying (bacteriostatic) so that the host's immune system can overcome them.

Oral antibiotics are the simplest approach when effective, with intravenous antibiotics reserved for more serious cases. Antibiotics may sometimes be administered topically, as with eyedrops or ointments.Antibiotics can also be classified by the organisms against which they are effective, and by the type of infection in which they are useful, which depends on the sensitivities of the organisms that most commonly cause the infection and the concentration of antibiotic obtainable in the affected tissue. Antibiotics are generally used to treat bacterial infections.

The toxicity to humans and other animals from antibiotics are generally considered to be low. However, prolonged use of certain antibiotics can decrease the number of gut flora, which can have a negative impact on health. Some recommend that during or after prolonged antibiotic use, that one should consume probiotics and eat reasonably to replace destroyed gut flora.

Bacteria

Bacteria (singular: bacterium) are microscopic, unicellular organisms. They are often coccus- (spherical) or rod-shaped and 0.5-5 um in the longest dimension, although the wide diversity of bacterial diversity can display a huge variety of morphologies. The study of bacteria is known as bacteriology, a branch of microbiology.

Bacteria are ubiquitous in the environment, living in every possible habitat on the planet.

There are typically ten billion bacterial cells in a gram of soil, and one hundred thousand bacterial cells in a millilitre of sea water. Bacteria play an important role in the cycling of nutrients in the environment, and many important steps in the nutrient cycle are catalysed exclusively by bacteria, such as the fixation of nitrogen from the atmosphere.

There are more bacterial cells on each of our bodies than there are our cells of our own and bacteria are a natural component of the human body, particularly on the skin and in the mouth and intestinal tract.

Yogurt is made with lactic cultures that are beneficial 'bacteria' which are allowed to multiply freely in temperature-controlled milk until it achieves a proper semisolid consistency and tart flavour.

Bacteriophage

A bacteriophage (from 'bacteria' and Greek phagein, 'to eat') is a virus that infects bacteria. The term is commonly used in its shortened form, phage.

Phages are ubiquitous and can be found in many reservoirs populated by bacteria, such as soil or the intestine of animals

Bifidobacterium

Bifidobacterium is a genus of bacteria that is naturally present in the human intestines. Different strains are known to have therapeutic properties that are beneficial to human health, and therefore Bifidobacteria are often added to yogurts as probiotics.

Research has found that the level of Bifidobacteria in adults is usually lower than children, due to a number of factors. In the elderly, the drop in Bifidobacteria level is further accelerated. For this reason, eating yogurt containing Bifidobacteria may help restoring a good balance of the intestine microflora.

Bulgaricus

One of the two types of beneficial bacteria found in yogurt and used in the preparation of it. They perform the acidation in the and are responsible for its coagulation. The bacteria were isolated and named by Professor Metchnikoff.

Calcium

Calcium is an essential mineral for the human body. Calcium is the principal building block for bone and teeth. Dairy products are typically an excellent source of calcium. Yogurt is made from milk, which naturally contains calcium.

Calories

Yogurt is typically low in calories and consequently is often recommended for dieters and weight watchers. Flavoured yogurts may have more calories, the amount varying according to the amount and type of sweetener.

Carbohydrate

Carbohydrate is the most common energy source especially for the brain, which requires glucose for its metabolism. It is commonly found in plants such as grains, legumes, fruits and vegetables; dairy products are the only animal-derived foods containing a significant amount of carbohydrate, in the form of lactose.

Casein

A major protein component in milk, the breakdown of which plays an important role in yogurt manufacture.

Clabber

Thick. sour, curdled or fermented milk. Clabber differs from yogurt in that it sours and thickens naturally. It is sometimes called bonnyclabber.

Cooking

Yogurt is a versatile ingredient in cookery. It should be warmed gently over low heat and cooked over even, moderate heat for a short time so it will not separate. Separating can be prevented by first stabilizing the yogurt. To do this, cornstarch or flour is mixed in water and added to the yogurt before cooking.

If you are using yogurt on its own, however, and the yogurt separates, the flavour is not affected but the dish is not as attractive. When adding yogurt to other ingredients it is generally best to fold or stir it in gently.

Colon Health

There's a medical truism that states: "You're only as healthy as your colon." When eating yogurt, you care for your colon in two ways. First, yogurt contains lactobacteria, intestines-friendly bacterial cultures that foster a healthy colon. Lactobacteria, especially acidophilus, promotes the growth of healthy bacteria in the colon and reduces the conversion of bile into carcinogenic bile acids.

The more of these intestines-friendly bacteria that are present in your colon, the better. Basically, the friendly bacteria in yogurt seems to deactivate harmful substances (such as nitrates and nitrites before they are converted to nitrosamines) before they can become carcinogenic. Secondly, yogurt is a rich source of calcium. Calcium discourages excess growth of the cells lining the colon, which can place a person at high risk for colon cancer.

Calcium also binds cancer-producing bile acids and keeps them from irritating the colon wall. People that have diets high in calcium (e.g. Scandinavian countries) have lower rates of colorectal cancer.

Culture

A colony of bacteria which is introduced into a nutrient substance. In order to make yogurt it is necessary to add culture to the fresh milk. This may be a small amount of previously prepared yogurt or a powdered culture that is sold in packages. The culture is sometimes called a "starter".

Cultured milk

Made by adding bacterial culture to milk. Buttermilk, sour cream and yogurt are examples of cultured milk products.

Curd

The coagulated part of milk that forms when milk proteins are broken down

Dahi

The Indian and Pakistani name for yogurt. Dahi normally differs from traditional ‘western’ yogurts in taste and texture (more butter-like), due to the different starter cultures used, which usually produces more diacetyl components.

Diarrhea

Some viral and allergic gastrointestinal disorders injure the lining of the intestines, especially the cells that produce lactase. This results in temporary lactose malabsorption problems. This is why children often cannot tolerate milk for a month or two after an intestinal infection.

Yogurt, however, because it contains less lactose and more lactase, is usually well-tolerated by healing intestines and is a popular "healing food" for diarrhea. Many pediatricians recommend yogurt for children suffering from various forms of indigestion.

Research shows that children recover faster from diarrhea when eating yogurt. It's good to eat yogurt while taking antibiotics. The yogurt will minimize the effects of the antibiotic on the friendly bacteria in the intestines.

A 1999 study reported in Pediatrics showed that lactobacillus organisms can reduce antibiotic-associated diarrhea.

Digestion

Yogurt is very easily digested and the cultures in yogurt assists the digestive system to assimilate other foods more effectively. Yogurt is converted into an absorbable form in only 30 to 40 minutes as compared to 3 to 4 hours for milk.

Fat content

Yogurt has a low fat content and because of this it is often regarded as a good diet food. One cup of plain yogurt, made from partially skimmed milk, has 4 grams of fat. One cup of plain yogurt, made from whole milk, has 8 grams of fat.

Fermentation

The process which occurs is yogurt after fresh milk has been inoculated with a culture. The chemical reactions caused by the fermentation change the milk to yogurt. The bacteria produces lactate and acetate during fermentation. The lactic acid it produces causes milk proteins to break down, coalescing into a more nearly solid gel substance - yogurt. By breaking down lactose to lactic acid, the bacteria make such dairy products digestible by most lactose intolerant people.

It is a well-known fact that fermented foods keeps for longer, and has better nutritive values, due to the fact that the level of micronutrients in food is increased by fermentation.

Freezing

It is not recommended that yogurt be frozen as the freezing and thawing adversely affect the smooth body and texture.

Immune System/Immunity

The immune system protects the body from infection by creating and maintaining barriers that prevent bacteria and viruses from entering the body. If a pathogen breaches the barriers, and gets into the body, the innate immune system is equipped with specialized cells that detect, and often eliminate, the invader before it is able to reproduce, potentially causing serious injury to the host.

A pathogen that successfully evades the innate immune cells faces a second, adaptive immune system. It is through the adaptive response that the immune system gains the ability to recognize a pathogen, and to mount stronger attacks each time that pathogen is encountered.[1]

Incubation

The period that the newly inoculated milk is kept warm so the bacteria will cause the milk to ferment, thicken and become yogurt.

Iron

Yogurt contains a small amount of iron. There is .1 milligram of iron in 1 cup of plain yogurt made from partially skimmed or whole milk.

Laban or leban

The name for yogurt in such Near Eastern countries as Iraq. Lebanon and Syria.

L.A.C.

Denotes Live Active Cultures which means that the bacterial cultures are still present in the yogurt because it has not been heat-treated. The National Yogurt Association in the USA makes available the L.A.C. seal to manufacturers whose yogurt meets the industry standard for live and active cultures. Heat-treated yogurt has been heated to kill the culture, thereby increasing the shelf life of the product.

Lactic acid

The clear, syrupy liquid formed by the fermentation of lactose when milk sours. It is present in all sour or fermented milks. Yogurt typically contains more than tree times the amount of lactic acid present in other fermented foods. Lactic acid assists the digestion of foods and plays an important role in several biochemical processes.

Lactobacillus

A genus of bacteria that forms a large part of the lactic acid bacteria group. Lactobacilli are naturally found in the human body, including the gastrointestinal tract where they are part of the gut microflora.

Lactase

An enzyme that breaks down the disaccharide lactose into its principal monosaccharide components: galactose and glucose.

Lactose

A white crystalline disaccharide made from whey and found in milk. It is also known as ‘milk sugar’. It is the only carbohydrate component of milk. Lactose is important in yogurt manufacture as it serves as a food source for the lactic acid bacteria, which convert it to lactic acid.

The lactic cultures in yogurt convert 25-30% of the lactose in milk to lactic acid. Plus they give their own bacterial lactase enzymes for your body to use to break down even more lactose.

Lactose intolerance

The inability to digest lactose due to the lack of the enzyme lactase. Approximately 70% of the world’s population has lactose intolerance to a varying degree. As a person ages, their lactase activity tends to decrease.

People who cannot tolerate milk can often eat a certain amount of yogurt without any intestinal upset. The culturing process makes yogurt more digestible than milk, by converting.lactose into glucose and galactose, two sugars that are easily absorbed by lactose-intolerant persons.

Mast

The Iranian or Persian name for yogurt.

Metchnikoff, Ilya

Also known as Elie Mechnikov. The Russian-born French bacteriologist and Nobel Prize winner (1908) who is credited with "rediscovering" yogurt. A member of the Pasteur Institute in Paris, he identified, isolated and named the beneficial bacteria in yogurt and championed its therapeutic values. His discoveries made it possible to produce yogurt on a large scale.

Minerals

One cup of yogurt, made of partially skimmed milk, typically contains .1 milligram of iron, 294 milligrams of calcium, 270 milligrams of phosphorous, 50 milligrams of potassium and 19 milligrams of sodium.

Osteoporosis

Osteoporosis is a serious health problem that has been associated by inadequate intake of calcium and vitamin D. It is caused by the decrease in bone mineral density (BMD) that weakens the bone and makes it more susceptible to breakage.

Yogurt and dairy products are typically a good source of calcium and therefore may help preventing osteoporosis in later life.

Probiotics

Proteins are the most versatile macronutrient which performs crucial functional and structural properties in human body. Dietary proteins are broken down in the body to amino acids, which are used in cell signaling, immune response, and used as building blocks of muscles, organs, and some hormones. Although human bodies can synthesize certain amino acids, there are nine essential amino acids that can only be obtained from food.

Protein

Yogurt is an excellent source of protein. The culturing of the milk proteins during fermentation makes these proteins easier to digest. For this reason, the proteins in yogurt are often called "predigested."

Refrigeration

Yogurt that is prepared in the home should be refrigerated after preparation to stop any further growth of bacteria. Commercial yogurt should be refrigerated as soon as possible and consumed within three or four days to give maximum flavour pleasure. If stored for longer periods, the acidity will continue to increase and the result will be a sharper flavoured product.

Sodium

Sodium is the principal cat ion (a positively charged ion) of the circulating blood and tissue fluids of animals. Normal sodium content is needed to maintain the correct volume of these fluids and the chemical balance of the body. Sodium also helps with the absorption of glucose in the small intestine and in the conduction of nerve impulses. Salt is a chemical compound that combines the elements sodium and chloride.

The recommended dietary intake (RDI) for sodium is 920 to 2300mg per day. In an everyday diet 75% comes from processed foods, 15% from personal use of salt at the table/cooking and <10% from fruit, vegetables and meat.

Soy

Lactic Bacteria can also be used to make "cultured soy" (commonly called soy yogurt) from soymilk in much the same way as fermentation of fresh milk.

Streptococcus thermophilus

One of the most desirable lactic bacteria and one of the main types of beneficial bacteria in yogurt. They quickly ferment milk sugar into lactic acid; inhibit growth of putrefactive bacteria; and are responsible for the flavour and aroma of yogurt.

Temperature

In the preparation of yogurt it is necessary to maintain an even and fairly high temperature so the bacteria will thrive in the milk. This is very important as bacteria will grow rapidly only in temperatures between 32°C. and 48°C. They are killed by higher temperatures and grow slowly or not at all in those below 32°C.

Virus

A virus that infects bacteria is known as a bacteriophage, often shortened to phage.

Vitamins

One cup of plain yogurt, made from partially skimmed milk, contains 170 international units of vitamin A, .10 milligram of vitamin B/thiamine, .44 milligram of vitamin B/riboflavin, .2 milligram of vitamin B/niacin, and 2 milligrams of vitamin C/ ascorbic acid.

Lactic acid bacteria have the property of being able to produce certain complex B vitamins (thiamine, riboflavin and niacin). The synthesis of folic acid (essential for the nervous system development in unborn babies) is particularly important.

Whey

Whey is the ‘watery’ part of milk which separates from the curds after coagulation. Whey is rich in nutreients including protein, lactose, vitamins, and minerals. Whey protein is one of the major source of protein in milk.