Yeast is a living, single-celled organism found in plants and animals. Yeast cells are ovoid and can only be seen through a microscope.
If you weigh the yeast and count the cells in them, then about 1 g of the substance will be about 20 billion cells. Since the human eye is unable to see a cell of 5 microns, these organisms have long remained one of the most mysterious. Until the middle of the 19th century, mankind generally knew little about them. It was only in 1866 that microbiologist Louis Pasteur, who had devoted his whole life to studying the principles of fermentation, became interested in the process of yeast fermentation using the example of beer. And after 15 years in a laboratory in Copenhagen, Emil Hansen isolated and purified individual yeast strains. The methods of cultivating yeast fungi according to the Hansen method are still used today.
Yeast cells are living organisms, and they need air to multiply. These cells must be nourished for energy. And their favorite food is everything sweet: sucrose (cane and beet sugar), fructose and glucose (honey, fruit, maple syrup), maltose (starch).
The size of a yeast cell does not exceed eight thousandths of a millimeter. There are approximately 1,500 types of yeast. Within one species there can be thousands of genetically different strains, but perhaps the most famous is Saccharomyces Cerevisiae, which in Latin means "sugar", "fungus" and "brewing". More often they are called by more understandable names - brewer's yeast or baker's. Each of these species has certain characteristics, and they determine the scope of the yeast. In brewing, for example, different strains are used to produce different types of beverage. But the scope of this substance is much wider. Yeast is used for the production of many products, they play the role of flavoring agents, and have also found application in pharmacology, animal husbandry and other areas.
Yeasts are organisms that need food, warmth and moisture to live and reproduce.
As a result of fermentation, they convert sugars and starches into carbon dioxide and alcohol. There are different types of yeast that are beneficial to human health. They can strengthen the immune system, improve digestion, but some cause fungal infections.
The most famous types of yeast:
The debate around unicellular fungi is not new. Many are interested in what baker's yeast actually is, the benefits or harms of them, some are scared by their composition according to GOST, therefore, more and more often housewives choose not domestic, but French yeast. In fact, if you understand what yeast is, how these microorganisms multiply and how they affect baking, it becomes clear that, by and large, there is nothing to worry about. Whether these substances are useful or, conversely, harmful to the body, depends on the amount of their consumption, the sensitivity of the body, as well as the presence of a fungus of the genus Candida in the body. In small quantities, yeast can improve health by replenishing B-group vitamins, but excess of the substance can adversely affect a person.
Studies have shown that yeast cells are largely similar to the cells of the human body. But while our bodies have tens of billions of cells, yeast has only one.
Man, as scientists say, is a eukaryotic organism. In simpler terms, it means that all of our genetic material is contained in the cell nucleus and mitochondria. By the same principle, nature created yeast, but bacteria are already representatives of prokaryotic organisms. And due to the fact that yeast is unicellular, it is easier for scientists to study their structure, properties and life stages. And from the point of view of structure, metabolism, of all biological models, it is yeast that is closest to humans. In addition, this fungus is the first eukaryotic microorganism whose genome scientists have deciphered by studying the exact sequence of all 16 chromosomes.
The importance of studying these microorganisms is also evidenced by the fact that over the past 15 years, the Nobel Prize in Medicine and Physiology has been awarded to yeast researchers twice. Using human genes in the fungus, scientists are testing the effectiveness of new drugs, studying the specifics of certain diseases.
Most of the research has focused on the potential use of yeast in the healthcare and food industries. Meanwhile, scientists have carried out other experiments. For example, not so long ago it became clear that some of the yeast strains could serve as the basis for the creation of biofuels for transport. By the way, a significant proportion of the insulin chemists create for diabetes is not produced without the help of yeast.
But this is far from all that a person has to learn about yeast. At least, scientists studying these micro-substances are convinced of this.
It should be noted that the development of yeast cells under different circumstances proceeds in different ways. And although these substances, from the point of view of biologists, are living organisms, they are so unique that they can live without air.
When the yeast does not receive oxygen, it acts on sugar to convert it into alcohol. In addition, carbon dioxide is emitted. This process occurs mainly during baking. As a result of this reaction, energy is released - the dough grows. Meanwhile, this energy is not enough for the yeast itself to continue to live. In the presence of oxygen, they, fed with sugar, grow and multiply very quickly, while releasing carbon dioxide, water and a relatively (by the standards of a fungus) a huge amount of energy.
Yeast, like bacteria, is essential for the human body. But the first thing to know about these microorganisms is that there are good and bad bacteria, and similarly with yeast. The fungus can infect organs and tissues, cause allergies and many diseases. Now let's try to understand the types of fungi and understand which of them are useful and which should be avoided.
Almost 80 percent of the world's population is said to fight this pathogenic yeast-like fungus, which causes inflammation in the body. Candida, like all yeast, is a single-celled organism that multiplies rapidly when there is a lot of sugar in the diet. This fungus robs the body of many nutrients, including iron and other minerals, making the blood acidic. Against the background of a sweet diet, Candida is even more active. If this process is not stopped in time, then harmful yeast will practically destroy the digestive and immune systems, deprive them of vitality. In return, they will cause frequent headaches, eczema, dandruff, dermatitis, hormonal disorders, vaginal infections, stomach ailments and confusion.
But besides the harmful ones, there are also beneficial yeasts. The best effect on the body is the fungi contained in probiotic foods. They strengthen the immune system and help fight candida. But foods that contain sugar are also not the best sources of this yeast.
Found in almost all probiotics, S. boulardii yeast has many beneficial properties:
Two more unusually beneficial yeast strains - Kluyveromyces marxianus var. Marxianus and Saccharomyces unisporus. They are contained mainly in kefir sourdough and play the role of a powerful amplifier for the immune system. Thanks to these components, kefir has been considered one of the best tonic drinks throughout the world for centuries. In ancient times, it was considered a drink of long-livers, and in Turkish its name sounds like "feel good".
Yeast is a wonderful ingredient that can help maintain or restore health and beauty naturally.
They are present in many foods, food supplements, and are also found in many cosmetics.
For many decades, yeast has been the focus of research, who unanimously recognize the extraordinary nutritional and therapeutic properties of this fungus. And all - thanks to the unique biochemical composition of these organisms. For humans, they serve as a source of amino acids, minerals, vitamins, enzymes and many other useful substances necessary for growth, proper metabolism and strengthening the immune system.
These microscopic substances are a source of nutrients and, fiber, many types of nutritional yeast, which is usually found exclusively in food of animal origin. In addition, yeast is an excellent source of plant proteins, making it an essential ingredient in vegetarian meals. And the high concentration of fiber provides a feeling of fullness for a long time. These elements are essential for the smooth functioning of the body. They are equally important for humans, animals and even plants.
The latter, just, are the object of recent research. As it turned out, yeast can act not only as a dietary supplement, but also as a useful natural fertilizer. Some strains contribute to a more efficient absorption of useful plants from soils. They also affect plant growth. At the same time, they are absolutely safe "fertilizer". Now scientists are trying to develop an effective yeast-based medicine against mold in fruits and other diseases - as a safe alternative to chemicals.
Perhaps no one will be surprised by the information that yeast is a useful bioactive additive used by people to treat and prevent a wide variety of conditions and diseases.
Yeast as a probiotic is a very promising solution. So scientists convince and add that the range of effects on humans of these microorganisms is very wide.
Scientists have discovered the relationship between yeast and intestinal microflora, in particular, the positive effects of the fungus on inflamed intestines.
Beneficial features:
An unpleasant side effect of taking yeast can be that it harbors not only beneficial bacteria, but also harmful bacteria, such as Candida, which cause asthma, gout, and other illnesses. With an exacerbation or onset of candidiasis, it is important to exclude all yeast foods from the diet for the period of treatment.
Yeast, as noted, is a form of mushroom. Most commonly used for baking and brewing. In this case, brewer's and baker's yeast are used. But besides them, there is also the so-called wild yeast, which can be found in fruits, berries (grapes) and grains.
Usually these microorganisms are well tolerated by humans, but there are people with intolerance. These are persons who are allergic to all types of fungi and mold.
Yeast extract is a food flavoring used in the preparation of bread, beer, cheese, soy sauce, and several other foods.
To understand how this substance affects the body, first you need to understand what it is in general.
Yeast extract is produced by mixing yeast and sugar under warm conditions. And with the subsequent breaking of cell membranes. This extract can be in gel or powder form. The use of yeast extract in food products may be labeled as “natural flavors” or “additives”.
You should know that this extract contains the amino acid glutamic acid. It is a naturally occurring form of the amino acid and should not be confused with monosodium glutamate as a flavor enhancer. And although the yeast extract also affects the taste, it acts like a spice. In addition, it also contains a high concentration of sodium. And this should be taken into account by people who have problems with blood pressure or those who, for other reasons, should not abuse sodium. In addition, the extract contains a very high concentration of B vitamins.
But despite all the benefits of this substance, it is important for people with food allergies or yeast sensitivities to avoid foods that contain fungal extract. The easiest way to do this is by avoiding convenience foods and prepared foods from supermarkets.
All products can be divided into 3 groups according to their yeast content. The first is food that contains fungi under all circumstances. In the second group of products, microorganisms are present only under certain conditions. And the third group is food that does not contain this substance.
The first group includes: bakery products, beer, cider, fruit skins (plums, grapes), grape juice, malt drinks, wine, yeast extract.
The second group includes: cakes, donuts, fruits (overripe), chocolate (some types), soy sauce.
The third group includes a huge number of products from different categories. In particular, you do not have to worry about the presence of yeast in eggs, seafood, different types of meats, raw nuts, beans, brown rice. You can also avoid unnecessary consumption of yeast if you refuse soy sauce during cooking and replace vinegar with lemon juice.
List of foods containing yeast:
Yeast can interfere with the effectiveness of some medicines. It is also important to avoid dietary supplements containing yeast for people who are allergic to the product or prone to yeast infections.
An important note for diabetics: Yeast can lower blood sugar levels, so it is advisable to regularly monitor your glucose reading.
Surely, you wondered what yeast is made of and how this process takes place. Now you will learn how to grow these single-celled mushrooms yourself at home.
Method one. Take 1 glass of water and flour, mix and leave for 7 hours. Then add a small spoonful of sugar and a glass of live beer to the mixture (has a shelf life of up to 2 weeks). Leave for a couple of hours. Store prepared brewer's yeast in a glass container in the refrigerator.
Method two. In a glass container, mix 200 g of raisins, milk, warm water and a little sugar. Cover the vessel tightly with gauze (fold in 4 layers and tie). Keep in a warm place for 5 days.
These recipes will create the common nutritional yeast that doctors recommend for a variety of conditions. This natural product will help with metabolic disorders, lack of B vitamins, digestive diseases, anemia, atherosclerosis, strengthen the body after flu or sore throat. By the way, home-made brewer's yeast is similar in its effect to medications containing these fungi, such as gefefitin.
Perhaps this happened in every housewife. I wanted to bake pies for dinner, but no yeast. But this is not a reason to be upset if you know how to make homemade yeast in sourdough form.
From 200 g of flour and a small amount of water, you need to knead a lump of dough, roll in flour and leave it on for a few. When the lump dries, hardens and becomes sour, you can use it instead of store yeast.
Peel and boil 10 potatoes, which are still hot, rub through a sieve. Add a tablespoon of flour, the same amount of honey and 25 grams of vodka. Leave the mixture warm for 2 days. When a frothy head forms on the surface, you can use a baking sourdough (take foam only).
The fact that yeast is an effective ingredient in many beauty products has been known for a long time. But not many people know that yeast-based cosmetics are easy to prepare on their own. Not sure how to do this? Read our recipes.
Dissolve a bag of dry yeast in cream and add 4 tablespoons of honey to the mixture. Leave on for 20 minutes. Apply to the body and leave on for 15-20 minutes. Rinse off with warm water. This mask improves blood circulation, tightens pores, makes the skin elastic and smooth.
Dissolve a tablespoon of brewer's yeast in a glass of kefir. Insist the mixture in a warm place for several hours. Apply to hair and keep for about half an hour. This mask will relieve dandruff.
Dilute about a teaspoon of brewer's yeast in a small amount of kefir. After the mixture is slightly infused in a warm place, and acquires the consistency of thin sour cream, apply to the skin of the face and keep for about 20 minutes. This remedy relieves acne, improves complexion, and is suitable for oily skin.
Interesting facts about yeast:
Many people ask the question: "Yeast is fungi or bacteria." And there is nothing strange in this, because until relatively recently, scientists themselves did not know the answer to this question. Today, there are other discussions about how safe it is to take yeast. And again, the answer is trivially simple: safe, if in moderation.
Yeast mushrooms (yeast fungi) is an extra-taxonomic position of unicellular fungi from the group of imperfect fungi that have lost their classical (mycelial) structure due to the transition of their habitat to liquid or semi-liquid substrates rich in organic matter.
They unite approximately 1,500 species, which mainly belong to the class of Ascomycetes and, less often, Basidiomycetes.
Yeast mushrooms (not to be confused with thermophilic yeast) - this is a collective type of fungi that do not have a typical mycelium and exist in the form of divided budding or dividing cells. They exist throughout their life, or most of it, in the form of completely separate single cells. And, due to their unicellular structure, they have a much higher metabolic rate than ordinary mycelial species, due to the relatively larger surface area of \u200b\u200btheir cells. Therefore, they always grow and multiply at an incredible speed.
Historically, such species have always been studied separately from others, due to the fact that the methods of their identification were more similar to bacteriological than to mycological. Well, according to the ability of sexual reproduction, these species are divided into subgroups located in different classes of fungi:
in the class of ascomycetes and basidials these are:
in the class of deuteromycetes, in which the sexual cycle is not found, these are:
The body of yeast fungi is very different from all others due to the fact that it consists of only one cell and therefore does not form mycelium (mycelium). And their reproduction is a very interesting phenomenon. A small protrusion appears on the cell, which grows, forming the so-called kidney and gradually turns into an independent cell, which is able to separate and, ultimately, is separated. This process is called budding.
For a long time, mankind has used fungi and yeast in baking and for the preparation of alcoholic beverages. In many languages \u200b\u200bof the world, their name is associated with the fermentation process that they cause. Their Russian name comes from the word "trembling" and it accurately characterizes the state of fermented wort or rising dough.
As already noted, about 1,500 species of imperfect mushrooms are known in nature, and we encounter many of them in everyday life. They are subdivided into:
For example, baker's yeast is used in bakery to make the dough rise and the baked goods become "fluffy", and in winemaking and brewing, wine and brewer's yeast are used, respectively, for the fermentation process. Thus, the indisputable fact becomes obvious: fungi and yeast were, are and will be constant companions and friends of man.
The fact that yeast is a mushroom is probably known to many. And what can be said about the further classification of these representatives of the kingdom? It is known that yeast belongs to the fungi of the ascomycete and basidiomycetes division. What does this mean? Let's try to figure it out together.
Moreover, they lost mycelium as a result of evolutionary processes, as it is believed, in connection with the transition to living in liquid substrates, which are rich in organic matter and are very favorable for the life of these organisms. There are up to one and a half thousand types of yeast in total. All yeasts are unicellular fungi.
Single isolated cells of these fungi reach up to 7 microns in diameter, but some grow up to 40 microns. However, some yeast-like ones still form mycelium at the stages of their life cycle, and in some cases - and a fruiting body. At present, for example, baker's yeast is the first eukaryotes whose genome has been identified and deciphered.
Yeast - mushrooms, "domesticated" by man, and for a long time. They have long been used for thousands of years for culinary purposes: baking, creating conditions for fermentation. Already in ancient Egypt there were bakeries and, obviously, yeast was used. And in some countries, in ancient times, along with baking unleavened bread (for example, matzo or lavash), yeast bread was also gaining popularity. They were known to the Egyptians for more than six thousand years ago, and with the help of these organisms, people brewed this foamy drink.
Interestingly, for the new sourdough, many farms have used the remnants of the old one since ancient times. So, according to scientists, the selection of yeast took place, species that did not occur in the wild appeared. And many consider some types of yeast to be a product exclusively (for example, varieties of cultivated grains: wheat, rye, and others).
This is the name of the science that describes and studies the life and activity of these organisms. Yeast is a mushroom, it was first isolated in 1881 in Denmark, and in 1883 it was already used for the production of beer. At the end of the 19th century, a classification of yeast was created, and in the 20th century, collections and keys of famous cultures appeared. Yeast belongs to the fungi of the ascomycete department until the middle of the last century. Scientists observed their sexual cycle, summarizing it as a taxonomic group. But in Japan, one of the scientists induced reproduction of Basidiomycete yeast as well. Thus, experts came to the conclusion that fungi-yeasts (photo below) were formed in the process of evolution independently among these two divisions of the kingdom (ascomycetes and basidiomycetes). The data was confirmed by the molecular biological study of organisms. They are not a taxon, but, most likely, a special life form.
So, yeast belongs to the fungi of the ascomycetes and basidiomycetes (more precisely, to two different departments). All of them are a sub-kingdom of the highest mushrooms. They can be distinguished by the characteristics of their life cycles and some other signs: pairs in DNA, the presence of urease. Ascomycetes, or marsupial mushrooms, are a fairly extensive department, including up to thirty thousand species (by the way, the well-known truffles belong to this department, as well as morels and lines). Among all - and yeast, which are considered by scientists to be secondary unicellular organisms.
Usually these organisms live in places that are rich in sugars - substrates on the surface of fruits and berries, leaves. They can feed on the waste products of plants: nectar, secretions, wound juices. They also do not disdain dead phytomass. They can live both in organic soil litters and in natural water masses. Some yeast is also present in the intestines of insects that feed on wood. There is a lot of yeast on the leaves, which are affected by aphids.
Some types of yeast cultures have long been in demand in cooking, baking and distilling. Kvass, bread, beer, wine cannot do without these tiny helpers. All these yeasts, known to mankind for a long time, belong to the fungi of the ascomycete department. For the production of strong alcohol, they are involved in distillation at the fermentation stage. Nowadays, some yeast cultures are used in a wide range of biotechnologies: the production of fuels and food additives and enzymes. And in science, they are used as experimental cultures for the research of geneticists.
Yeast belongs to the group of unicellular fungi that have lost their mycelial structure, because their habitats have become substrates of a liquid or semi-liquid consistency, containing a large amount of organic matter. The group of yeast fungi includes 1500 species that belong to the classes of Basidiomycetes and Ascomycetes.
In nature, yeast is widespread and lives on substrates rich in sugars, feeding on flower nectar, plant juices, dead phytomass, etc. Yeast fungi can live in soil and water, in the intestines of animals.
Yeast is a fungus that lives during all or most of its life cycle in the form of individual single cells. The size of yeast cells is on average from 3 to 7 microns in diameter, but there are some species, the cells of which can reach 40 microns. Yeast cells are immobile and oval in shape. Although yeast does not form mycelium, it exhibits all the characteristics and properties of fungi. Yeast fungi are organotrophic eukaryotes with an absorption type of nutrition. These mushrooms use organic matter to produce carbon and energy necessary for life. Yeast needs oxygen to breathe, but in the absence of oxygen access, many types of facultative anaerobes of yeast fungi receive energy as a result of fermentation to form alcohols. Yeast fermentation is suspended or stopped altogether if oxygen begins to flow to the fermentable substrate, since respiration is a more efficient process for obtaining energy. But if the concentration of sugars in the nutrient medium is very high, then even with the access of oxygen, the processes of respiration and fermentation are carried out simultaneously. Yeast mushrooms are very demanding for nutritional conditions. In an anaerobic environment, yeast assimilates only glucose, while in an aerobic environment, it can also use hydrocarbons, fats, aromatic compounds, organic acids, and alcohols as energy sources.
Growth and multiplication of yeast occurs at a tremendous rate, while provoking characteristic changes in the environment. So, thanks to the process of alcoholic fermentation, yeast has become widespread throughout the world. Yeast is believed to be the oldest plant cultivated by humans.
Yeast propagation is carried out by budding (division). Sexual reproduction is also possible. In this case, the resulting zygote is transformed into a "bag", which contains 4-8 spores. In a unicellular state, yeast is capable of vegetative reproduction. So, spores or zygotes can bud. The division of yeast into groups (classes Ascomycetes or Basidiomycetes) is based on the methods of their sexual reproduction. There are types of yeast that do not have sexual reproduction. Scientists included them in the class of imperfect fungi (Fungi Imperfecti, or Deuteromycetes).
Since ancient times, certain types of yeast have been used by humans in the manufacture of wine, beer, bread, kvass, in the industrial production of alcohol, etc. Some types of yeast are used in biotechnology due to their important physiological characteristics. In modern production, using yeast, food additives, enzymes, xylitol are obtained, and water is purified from oil pollution. But there are also negative properties of yeast. Some types of yeast can cause disease in humans, as they are facultative or opportunistic microorganisms. Such diseases include candidiasis, cryptococcosis, pityriasis.
Yeast fungus, the treatment of which is not particularly difficult, is a fairly common disease among women and men. Treatment of a yeast fungus must be carried out in a timely manner, since a yeast infection can cause serious pathologies.
The human body is inhabited by thousands of species of fungi and bacteria that form the microflora of various organs. A number of external factors, pathologies and disorders in the human body can provoke the rapid multiplication of yeast and fungi. Among the main factors are:
Only a doctor can identify and determine the presence of harmful microflora. The diagnosis is made after examination and testing. The main symptoms of the disease:
Yeast can affect both women and men.
Fungal infection (candidiasis) can be transmitted by airborne droplets, through objects and food, and through sexual contact.
Fungi begin to multiply actively on the skin and mucous membranes of a person. Doctors distinguish several types of the disease:
In most cases, yeast is found on the face, armpits, and groin. After detecting pathogenic microflora, the doctor prescribes the appropriate treatment for the fungus.
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Yeast fungi, which can be treated at home, can be overcome with the following drugs:
Some of these drugs are taken by mouth. Other medicines in the form of ointments, creams, solutions and suppositories are applied to the skin and mucous membranes. It is necessary to treat candidiasis in a comprehensive manner. From external agents, sodium tetraborate solution can be isolated. At any stage of the disease, therapy with fortifying and immunostimulating drugs is additionally prescribed. It will not be superfluous to take lactic acid bacteria or lactobacilli.
Do not forget about proper nutrition and taking probiotics. Probiotics contain lactulose, which the body needs to fight disease. The most popular drugs are:
carried out using special ointments, gels, varnishes, solutions and sprays. Among such funds, one can distinguish Lotseril varnish. The varnish penetrates deep into the skin and destroys the fungus. In parallel, terbinafine or diflucan preparations are prescribed. With severe inflammation, antibiotic therapy may be prescribed. The dosage of drugs, the frequency and duration of treatment is determined only by the attending physician.
When using combined therapy with Lumexin and Fluconazole. Antimicrobial drugs are prescribed to suppress the growth of anaerobic bacteria. If vaginal candidiasis is not treated promptly, there is a risk of infection spreading to the bladder and large intestine. Treatment of chronic forms can take many months. Also, the patient should stop smoking and drinking alcohol.
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In folk medicine, there are a lot of recipes and recommendations that will help get rid of yeast. From the means of local application, one can single out:
From recipes for internal use have been proven to be effective:
Any treatment with folk remedies should be agreed with the attending physician. Doctors advise that in order to prevent the disease, you need to maintain hygiene, maintain your immunity and eat only healthy food.