Yeast Extract’s Recent Origins
After centuries of using yeast for the production of beer, bread, and wine, a new possibility was discovered for yeast in the 19th century by Professor von Liebig. Von Liebig was the first scientist to discover that yeast could be an exciting new substitute for the taste profile of meat in cooking. After this discovery, at the beginning of the 20th century, the interest in yeast as an aromatic base to improve the flavors of soups, sauces, broths, and other dishes was developed until in the 1950s, yeast extract was introduced to the market.
Source: Biospringer by Lesaffre 2022
Yeast Extract is an Ingredient From Nature
Yeast extract comes from fresh yeast and is, therefore, an ingredient of natural origin. No animal substances are added during its production. It keeps its natural attributes and organoleptic qualities throughout the whole manufacturing process.
The composition of yeast extract is based on the same composition of yeast: proteins, free amino acids, carbohydrates, vitamins, and minerals (Figure 1).
Figure 1. Yeast extracts composition
Source: Biospringer by Lesaffre 2022
How are Yeast Extracts Produced?
Making extracts is a meticulous process. It requires three steps, which must be completed with the utmost precision.
Yeast extracts all begin with fresh yeast which is composed of:
- A cell wall, to separate and protect the yeast cell from the extracellular environment,
- A cytoplasm rich in nutrients such as proteins, free amino acids, vitamins, and minerals,
- A nucleus, location of the precious DNA molecule of the yeast, its genetic information.
Making extracts consists of 3 steps:
1. Fermentation: depending on the uses, a specific yeast strain is selected. Once this selection is made, fermentation starts. It is conducted in tanks under regular growing conditions: a glucose source, a monitored temperature (around 30°C/86°F), and a sufficient oxygen supply. Those conditions are essential for the efficient growth and the multiplication of the yeast population. This first step results in what is called “yeast cream.”
Source: Biospringer by Lesaffre 2022
2. Breakage: induces solubilization of the yeast cell content. This is done through heat and the enzymes naturally present in the yeast cell. After cooling to stop the multiplication of the yeast population, the yeast cream is placed in large tanks at a temperature of 45-55°C (113-131°F) causing the inner enzymes to break down the proteins and other macromolecules into smaller molecules. This step is also known by scientists as “autolysis.” Breakage allows for the selection of tastiest components (elementary particles):
- Protein portions: peptides and free amino acids such as glutamic acids.
- Nucleic acid: Ribonucleic Acid (RNA), Oligonucleotides, and Nucleotides (IMP-GMP).
- Polysaccharides: sugars, mannans, and glucans.
Each parameter of the breakage (duration, temperature, and pH) is crucial and influences the final tasting properties of yeast extract.
Source: Biospringer by Lesaffre 2022
3. Separation: centrifugation allows for the separation of the cell walls from the tasty components and nutrients obtained during the breakage. Every nutrient from the initial yeast is preserved in the yeast extract. This centrifugation ends with a flavorful solution, which is concentrated. At the end of this step, water is evaporated, and nothing remains except the yeast extract!
Source: Biospringer by Lesaffre 2022
This is all done without any chemical additives.
The result of this process is a yeast extract powder, liquid, or paste.
Source: Biospringer by Lesaffre 2022
Basically, yeast extract is only yeast, without its cell wall – Nothing else.
Yeast Extract: The Flavor Saver!
Like traditional yeast, yeast extracts offer high nutritional value but do not have the same purpose. Instead of being used to initiate fermentation like how yeast is used when making bread, yeast extracts are used as an herb or spice to improve the taste of dishes when used in cooking.
So what does yeast extract taste like and how is it used?
The taste of yeast extract is similar to vegetable, meat, or poultry stock. This is explained by the fact that these stocks contain the same proteins as yeast extract. Even more to the point, yeast extract contains 5% natural glutamate, which gives it a specific taste profile commonly known as “umami.” This same flavor profile can be found in tomatoes, Parmesan cheese, and soy sauce. Umami is considered the fifth flavor. Ingredients with an umami profile are believed to enhance the other four flavors: sweet, bitter, sour, and salty. Therefore, ingredients with this flavor, like yeast extract, can be added to dishes and food products to more easily recognize the other four flavors. This makes the food taste richer and better!
As mentioned, yeast extracts are used to improve the flavor of many food products:
- soups,
- sauces,
- stock cubes,
- savory snacks,
- other snacks,
- prepared dishes,
- sausages,
- and pretty much anything else you want to add a richer flavor too!
Yeast extracts are also vegan and vegetarian as well as being halal and kosher!
Therefore, its taste value allows vegetarians and vegans to flavor their dishes without adding animal ingredients.
Furthermore, yeast extract allows food manufacturers and home cooks to engage in a nutritional improvement approach to reduce salt, fat, or sugar content in their dishes while keeping pleasure and taste in their foods.
So, if you want to add some additional flavor as well as a host of nutritional benefits, while at the same time reducing your salt, fat and sugar intake give yeast extract a try! Who knows it may just be the next best thing since sliced bread!
