Yeast extracts consist of the cell contents of

yeast Yeasts are eukaryotic, single-celled microorganisms classified as members of the fungus kingdom. The first yeast originated hundreds of millions of years ago, and at least 1,500 species are currently recognized. They are estimated to constitut ...

without the

cell walls A cell wall is a structural layer surrounding some types of cells, just outside the cell membrane. It can be tough, flexible, and sometimes rigid. It provides the cell with both structural support and protection, and also acts as a filtering mech ...

; they are used as

food additive Food additives are substances added to food to preserve flavor or enhance taste, appearance, or other sensory qualities. Some additives have been used for centuries as part of an effort to preserve food, for example vinegar (pickling), salt (sal ...

s or

flavorings A flavoring (or flavouring), also known as flavor (or flavour) or flavorant, is a food additive used to improve the taste or smell of food. It changes the perceptual impression of food as determined primarily by the chemoreceptors of the gustato ...

, or as nutrients for

bacterial culture A microbiological culture, or microbial culture, is a method of multiplying microbial organisms by letting them reproduce in predetermined culture medium under controlled laboratory conditions. Microbial cultures are foundational and basic diagn ...

media Media may refer to: Communication * Media (communication), tools used to deliver information or data ** Advertising media, various media, content, buying and placement for advertising ** Broadcast media, communications delivered over mass ...

. They are often used to create savory flavors and

umami Umami ( from ja, 旨味 ), or savoriness, is one of the five basic tastes. It has been described as savory and is characteristic of broths and cooked meats. People taste umami through taste receptors that typically respond to glutamates and ...

taste sensations, and can be found in a large variety of packaged food, including frozen meals, crackers, snack foods, gravy, stock and more. They are rich in

B vitamins B vitamins are a class of water-soluble vitamins that play important roles in cell metabolism and synthesis of red blood cells. Though these vitamins share similar names (B1, B2, B3, etc.), they are chemically distinct compounds that often coexi ...

(but not

B12 Vitamin B12, also known as cobalamin, is a water-soluble vitamin involved in metabolism. It is one of eight B vitamins. It is required by animals, which use it as a cofactor in DNA synthesis, in both fatty acid and amino acid metabolism. It ...

). Yeast extracts and

fermented Fermentation is a metabolic process that produces chemical changes in organic substrates through the action of enzymes. In biochemistry, it is narrowly defined as the extraction of energy from carbohydrates in the absence of oxygen. In food p ...

foods contain

glutamic acid Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...

(free glutamates), an amino acid which adds an umami flavor. Glutamic acid is found in meat, cheese, fungi (mushrooms and yeast), and vegetables—such as broccoli, and tomatoes. The heat-autolytic process to make yeast extract of the autolysate type was invented in the 19th century by

Justus von Liebig Justus Freiherr von Liebig (12 May 1803 – 20 April 1873) was a German scientist who made major contributions to agricultural and biological chemistry, and is considered one of the principal founders of organic chemistry. As a professor at the ...

. Yeast cells are heated until they rupture, then the cells' own digestive

enzyme Enzymes () are proteins that act as biological catalysts by accelerating chemical reactions. The molecules upon which enzymes may act are called substrates, and the enzyme converts the substrates into different molecules known as products. ...

s break their proteins down into simpler compounds (

amino acids Amino acids are organic compounds that contain both amino and carboxylic acid functional groups. Although hundreds of amino acids exist in nature, by far the most important are the alpha-amino acids, which comprise proteins. Only 22 alpha am ...

and

peptides Peptides (, ) are short chains of amino acids linked by peptide bonds. Long chains of amino acids are called proteins. Chains of fewer than twenty amino acids are called oligopeptides, and include dipeptides, tripeptides, and tetrapeptides. A p ...

), a process called autolysis. The insoluble cell walls are then separated by

centrifuge A centrifuge is a device that uses centrifugal force to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or l ...

filtered Filtration is a physical separation process that separates solid matter and fluid from a mixture using a ''filter medium'' that has a complex structure through which only the fluid can pass. Solid particles that cannot pass through the filter m ...

, and usually spray-dried. This is the process used for Vegemite, Marmite, and the like. Yeast extracts in liquid form can be dried to a light paste or a dry powder. This is not the same as

nutritional yeast Nutritional yeast (also known as nooch) is a deactivated yeast, often a strain of ''Saccharomyces cerevisiae'', that is sold commercially as a food product. It is sold in the form of yellow flakes, granules, or powder and can be found in the bul ...

, which are made from intact cells not directly hydrolyzed and consequently have a lighter flavor.

Production

Yeast extracts in general are produced in three steps: fermentation (growing the yeast), disruption (breaking of the cells), and separation (to keep the soluble part). Although the vast majority of yeast extract spreads are made using von Liebig's traditional approach of heat-autolysis using surplus yeast from beer brewing, other methods do exist for producing specialized types. In terms of fermentation, spent beer yeast is commonly contaminated with the bitter compounds from

hops Hops are the flowers (also called seed cones or strobiles) of the hop plant ''Humulus lupulus'', a member of the Cannabaceae family of flowering plants. They are used primarily as a bittering, flavouring, and stability agent in beer, to whi ...

, requiring a "debittering" step to wash out most of this undesired flavor. Yeast from other sources are not affected by this issue. Spent brewer's yeast is also quite

biodiverse Biodiversity or biological diversity is the variety and variability of life on Earth. Biodiversity is a measure of variation at the genetic (''genetic variability''), species (''species diversity''), and ecosystem (''ecosystem diversity'') le ...

, containing yeasts other than traditional ''Saccharomyces cerevisiae'' and sometimes beer spoilage-causing

lactic acid bacteria Lactobacillales are an order of gram-positive, low-GC, acid-tolerant, generally nonsporulating, nonrespiring, either rod-shaped (bacilli) or spherical ( cocci) bacteria that share common metabolic and physiological characteristics. These bacte ...

too. For disruption of the cell, some physical and chemical methods may be used in place of the heat-autolysis process. Doing so may allow specific compounds to be extracted or to produce an extract without the hydrolysis of cell contents (as in autolysis) happening.

Dietary concerns

Depending on the source, yeast extract may contain

gluten Gluten is a structural protein naturally found in certain cereal grains. Although "gluten" often only refers to wheat proteins, in medical literature it refers to the combination of prolamin and glutelin proteins naturally occurring in all grai ...

. Brewer's yeast are especially likely to contain the protein due to contact with the grains used in brewing. In the case of yeast autolysate, however, the yeast

protease A protease (also called a peptidase, proteinase, or proteolytic enzyme) is an enzyme that catalyzes (increases reaction rate or "speeds up") proteolysis, breaking down proteins into smaller polypeptides or single amino acids, and spurring the form ...

s are able to degrade most of the gluten. For example,

Marmite Marmite ( ) is a British savoury food spread based on yeast extract, invented by the German scientist Justus von Liebig. It is made from by-products of beer brewing ( lees) and is produced by the British company Unilever. Marmite is a vegan ...

contains around 30

part per million In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they ...

gluten according to third-party testing, meeting the EU "very low gluten" limit but not the "gluten free" definition. Unilever reports that no cases of gluten-related reactions have been reported for Marmite. Yeast extract products derived from plant feedstock are by definition

vegan Veganism is the practice of abstaining from the use of animal product—particularly in diet—and an associated philosophy that rejects the commodity status of animals. An individual who follows the diet or philosophy is known as a vegan. ...

and

kosher (also or , ) is a set of dietary laws dealing with the foods that Jewish people are permitted to eat and how those foods must be prepared according to Jewish law. Food that may be consumed is deemed kosher ( in English, yi, כּשר), from ...

–

pareve In ''kashrut'', the dietary laws of Judaism, pareve (from yi, פאַרעוו for "neutral", in Hebrew , and also parve and other variant English spellings) is a classification of edible substances that contain neither dairy nor meat ingredients. ...

, although some consumers prefer extra certification. They are also generally considered

halal ''Halal'' (; ar, حلال, ) is an Arabic word that translates to "permissible" in English. In the Quran, the word ''halal'' is contrasted with ''haram'' (forbidden). This binary opposition was elaborated into a more complex classification kn ...

, despite the concern that the yeast has come into contact with alcohol.

Use in food

Yeast autolysates are the main ingredient in

AussieMite AussieMite is an Australian savoury food spread made from hydrolyzed vegetable protein and yeast extract fortified with B vitamins and iron. It was founded by Roger Ramsey in 2001. The taste of the product is slightly salty and is used for toas ...

, Mightymite,

Vegemite Vegemite ( ) is a thick, dark brown Australian food spread made from leftover brewers' yeast extract with various vegetable and spice additives. It was developed by Cyril Callister in Melbourne, Victoria, in 1922. A spread for sandwiches ...

, New Zealand Marmite,

Promite Promite is a dark brown, salty food paste derived from yeast extract. It is primarily used as a spread on sandwiches and toast similar to Vegemite and Marmite. Promite was invented in the 1950s by Henry Lewis & Company and marketed under the Mas ...

Cenovis Cenovis is a dark brown food paste from Switzerland consisting of yeast extract. It is similar to English Marmite, Brazilian Cenovit, and Australian Vegemite. It is rich in vitamin B1. It is used to flavour soups, sausages, and salads. The most ...

, Vitam-R, Brazilian Cenovit and Maggi sauce.

Bovril Bovril is the trademarked name of a thick and salty meat extract paste similar to a yeast extract, developed in the 1870s by John Lawson Johnston. It is sold in a distinctive bulbous jar, and as cubes and granules. Bovril is owned and distribu ...

(

Ireland Ireland ( ; ga, Éire ; Ulster-Scots: ) is an island in the North Atlantic Ocean, in north-western Europe. It is separated from Great Britain to its east by the North Channel, the Irish Sea, and St George's Channel. Ireland is the s ...

and the

United Kingdom The United Kingdom of Great Britain and Northern Ireland, commonly known as the United Kingdom (UK) or Britain, is a country in Europe, off the north-western coast of the continental mainland. It comprises England, Scotland, Wales and Nor ...

) switched from beef extract to yeast extract for 2005 and most of 2006, but later switched back. Yeast extract is used as a flavoring in foods. It is a common ingredient in American barbecue-flavored

potato chip A potato chip (North American English; often just chip) or crisp (British and Irish English) is a thin slice of potato that has been either deep fried, baked, or air fried until crunchy. They are commonly served as a snack, side dish, or appe ...

s such as

Lay's Lay's is a brand of potato chips, as well as the name of the company that founded the chip brand in the United States. The brand is also referred to as Frito-Lay because both Lay's and Fritos are brands sold by the Frito-Lay company, which has b ...

. It is also widely used in soup bases.

Marmite

Marmite ( ) is a British food spread produced by

Unilever Unilever plc is a British multinational consumer goods company with headquarters in London, England. Unilever products include food, condiments, bottled water, baby food, soft drink, ice cream, instant coffee, cleaning agents, energy drink, ...

. Marmite has been produced since 1902. It is a sticky, dark brown

food paste A food paste is a semi-liquid colloidal suspension, emulsion, or aggregation used in food preparation or eaten directly as a spread. Pastes are often highly spicy or aromatic, are often prepared well in advance of actual usage, and are often mad ...

with a distinctive, powerful flavour, which is extremely salty. This distinctive taste is represented in the marketing slogan: "Love it or hate it." Such is its prominence in

British popular culture British culture is influenced by the combined nations' history; its historically Christian religious life, its interaction with the cultures of Europe, the traditions of England, Wales, Scotland and Ireland and the impact of the British Empire. ...

that the product's name is often used as a metaphor for something that is an

acquired taste An acquired taste is an appreciation for something unlikely to be enjoyed by a person who has not had substantial exposure to it. It is the opposite of innate taste, which is the appreciation for things that are enjoyable by most persons without ...

or tends to polarise opinions. In

Australasia Australasia is a region that comprises Australia, New Zealand and some neighbouring islands in the Pacific Ocean. The term is used in a number of different contexts, including geopolitically, physiogeographically, philologically, and ecologi ...

and the Pacific, British Marmite is sold as "Our Mate", due to the presence of a licensed Marmite produced in New Zealand.

Vegemite

Vegemite ( ) is a thick, black Australian food spread made from leftover brewers' yeast extract with various vegetable and spice

additives Additive may refer to: Mathematics * Additive function, a function in number theory * Additive map, a function that preserves the addition operation * Additive set-functionn see Sigma additivity * Additive category, a preadditive category with fi ...

. It was developed by Cyril Percy Callister in

Melbourne Melbourne ( ; Boonwurrung/Woiwurrung: ''Narrm'' or ''Naarm'') is the capital and most populous city of the Australian state of Victoria, and the second-most populous city in both Australia and Oceania. Its name generally refers to a metrop ...

Victoria Victoria most commonly refers to: * Victoria (Australia), a state of the Commonwealth of Australia * Victoria, British Columbia, provincial capital of British Columbia, Canada * Victoria (mythology), Roman goddess of Victory * Victoria, Seyche ...

, in 1922. The Vegemite brand was owned by

Mondelez International Mondelez International, Inc. ( ), often styled Mondelēz, is an American multinational confectionery, food, holding and beverage and snack food company based in Chicago. Mondelez has an annual revenue of about $26 billion and operates in ...

(formerly

Kraft Foods Inc. Kraft Foods Inc. was a multinational confectionery, food and beverage conglomerate. It marketed many brands in more than 170 countries. 12 of its brands annually earned more than $1 billion worldwide: Cadbury, Jacobs, Kraft, LU, Maxwell Ho ...

)"The Vegemite Story"
Kraft Foods. until January 2017, when it was acquired by the Australian

Bega Cheese Bega Cheese is an Australian diversified food and drinks company with manufacturing sites in New South Wales, Queensland, Western Australia and Victoria. Founded as an agricultural cooperative in the town of Bega, New South Wales by their dair ...

group in a agreement for full Australian ownership after Bega would buy most of Mondelez International's Australia and New Zealand grocery and cheese business. A spread for sandwiches, toast,

crumpets A crumpet () is a small griddle bread made from an unsweetened batter of water or milk, flour, and yeast, popular in the United Kingdom, Canada, New Zealand, South Africa and Australia. Crumpets are regionally known as pikelets, a name also a ...

and cracker biscuits as well as a filling for pastries, Vegemite is similar to British Marmite, New Zealand Marmite, Australian

, MightyMite,

, OzEmite, Brazilian Cenovit, German

Vitam-R Yeast extracts consist of the cell contents of yeast without the cell walls; they are used as food additives or flavorings, or as nutrients for bacterial culture media. They are often used to create savory flavors and umami taste sensations, a ...

, and Swiss

. Vegemite is salty, slightly bitter,

malt Malt is germinated cereal grain that has been dried in a process known as " malting". The grain is made to germinate by soaking in water and is then halted from germinating further by drying with hot air. Malted grain is used to make beer, ...

y, and rich in

glutamates Glutamic acid (symbol Glu or E; the ionic form is known as glutamate) is an α-amino acid that is used by almost all living beings in the biosynthesis of proteins. It is a non-essential nutrient for humans, meaning that the human body can syn ...

– giving it an

flavour similar to beef bouillon. It is

, and

Marmite (New Zealand)

Marmite ( /ˈmɑːrmaɪt/ ''MAR-myte'') is a food spread produced in New Zealand by

Sanitarium Health and Wellbeing Company The Sanitarium Health and Wellbeing Company is the trading name of two sister food companies (Australian Health and Nutrition Association Ltd and New Zealand Health Association Ltd). Both are wholly owned by the Seventh-day Adventist Church. F ...

and distributed in Australia and the Pacific. It is similar to the British

, but the two products are made by different companies. This is the only product sold as Marmite in

and the Pacific, whereas elsewhere in the world the British version predominates. In the rest of the world it is sold as "NZ-Mite". Marmite has been manufactured in New Zealand since 1919. The product's popularity in England prompted the Sanitarium Health Food Company to obtain sole rights to distribute the product in New Zealand and Australia in 1908. They later began manufacturing Marmite under licence in

Christchurch Christchurch ( ; mi, Ōtautahi) is the largest city in the South Island of New Zealand and the seat of the Canterbury Region. Christchurch lies on the South Island's east coast, just north of Banks Peninsula on Pegasus Bay. The Avon River ...

, albeit using a modified version of the original recipe, most notable for its inclusion of sugar and caramel. Common ingredients are also slightly different quantities from the British version; the New Zealand version has high levels of

potassium Potassium is the chemical element with the symbol K (from Neo-Latin ''kalium'') and atomic number19. Potassium is a silvery-white metal that is soft enough to be cut with a knife with little force. Potassium metal reacts rapidly with atmosp ...

, for example. New Zealand Marmite is described as having a "weaker" or "less tangy" flavour than the British version.

Vitam-R

Vitam-R is a savory yeast extract spread made in

Hameln Hamelin ( ; german: Hameln ) is a town on the river Weser in Lower Saxony, Germany. It is the capital of the district of Hamelin-Pyrmont and has a population of roughly 57,000. Hamelin is best known for the tale of the Pied Piper of Hamelin. H ...

, Germany, by the company Vitam Hefe-Produkt GmbH. It was first developed by Rückforth AG in

Stettin Szczecin (, , german: Stettin ; sv, Stettin ; Latin: ''Sedinum'' or ''Stetinum'') is the capital and largest city of the West Pomeranian Voivodeship in northwestern Poland. Located near the Baltic Sea and the German border, it is a major se ...

(today's

Szczecin Szczecin (, , german: Stettin ; sv, Stettin ; Latin: ''Sedinum'' or ''Stetinum'') is the capital and largest city of the West Pomeranian Voivodeship in northwestern Poland. Located near the Baltic Sea and the German border, it is a major s ...

Poland Poland, officially the Republic of Poland, is a country in Central Europe. It is divided into 16 administrative provinces called voivodeships, covering an area of . Poland has a population of over 38 million and is the fifth-most populou ...

) in 1925, following the discovery by

that yeast could be concentrated. It is sometimes described as having a smoother flavor than similar products such as

, or

. Unlike those brands, Vitam-R is not an iconic part of its home country's

cuisine A cuisine is a style of cooking characterized by distinctive ingredients, techniques and dishes, and usually associated with a specific culture or geographic region. Regional food preparation techniques, customs, and ingredients combine to ...

, but it, too, is described as having a love-it-or-hate-it flavor. It is both

and by extension,

vegetarian Vegetarianism is the practice of abstaining from the consumption of meat (red meat, poultry, seafood, insects, and the flesh of any other animal). It may also include abstaining from eating all by-products of animal slaughter. Vegetarianism m ...

, and is sold primarily in

Reformhaus ''Reformhaus'' ("reform house") is a type of German retail store that specializes in groceries and personal care products according to the principles of the 19th-century ''Lebensreform'' movement, for example the products are vegetarian, often ( ...

health-food stores.

Cenovis

Cenovis is a product based on yeast extract that is similar to Marmite and Vegemite, rich in vitamin B₁. In the form of a dark brown food paste, it is used to flavour soups, sausages, and salads. The most popular way to consume Cenovis, however, is to spread it on a slice of buttered bread, as stated on the product's packaging (it can also be blended directly into butter, and then spread on bread, or used as a filling in croissants and buns). Cenovis is popular in

Switzerland ). Swiss law does not designate a ''capital'' as such, but the federal parliament and government are installed in Bern, while other federal institutions, such as the federal courts, are in other cities (Bellinzona, Lausanne, Luzern, Neuchâtel ...

(particularly

Romandie Romandy (french: Romandie or )Before World War I, the term French Switzerland (french: Suisse française) waalso used german: Romandie or , it, Romandia, rm, Romanda) is the French-speaking part of western Switzerland. In 2020, about 2 mill ...

). It was developed in Rheinfelden in 1931, on the initiative of a master brewer named Alex Villinger, (French) and was subsequently produced by the company Cenovis SA.

Other uses

The nutrition-rich nature of yeast extract lends it to a variety of uses. It was historically popular as a vitamin supplement for humans. Rich in proteins and nucleotides, it currently finds use in animal feed and microbiology (see

yeast extract agar Yeast extract agar is a growth medium containing yeast extract. It may refer to: * The nonselective yeast extract agar of Windle Taylor * YM (selective medium), for yeasts and molds * Buffered charcoal yeast extract agar, for ''Legionella ''Le ...

) as nutritional supplements. It also finds use in

cosmetics Cosmetics are constituted mixtures of chemical compounds derived from either natural sources, or synthetically created ones. Cosmetics have various purposes. Those designed for personal care and skin care can be used to cleanse or protect ...

and skincare products due to moisturizing and alleged antioxidant properties.

References

External links

yeastextract.info
Homepage of Eurasyp (European Association of Specialty Yeast Products)
Savory Taste Alliance
{{DEFAULTSORT:Yeast Extract Food ingredients Microbiological media ingredients Umami enhancers Yeasts