Fermentation Industry Flashcards
an enzyme-catalyzed metabolic process whereby organisms convert starch or sugar to alcohol or an acid, anaerobically releasing energy.
Fermentation
involves the breakdown of carbohydrates into simpler compounds, primarily to generate energy for microorganisms. The process typically follows glycolysis, leading to the production of pyruvate, which can be further transformed into ethanol, lactic acid, or acetic acid, depending on the microorganism involved.
Fermentation
The word fermentation originally came from a Latin word “______” that means to boil.
fervere
First discovered accidentally by nomadic herders in Central Asia.
Early Yogurt Fermentation (~10 000 BC)
Used in producing bread, vinegar, and soy sauce.
Spontaneous Fermentation (~5000 BC)
Most fermentations require liquid media often referred to as broth, although some solid-substrate fermentations are operated.
Media Formulation
Types of Media
- Simple Media
- Complex Media
only the simplest of inorganic medium such as a few inorganic salts, water and nitrogen sources. From the simple inorganic nutrients, they can synthesize all of the complex organic compounds required to sustain life. Media consisting of few ingredients. Autotrophic organisms require
Simple Media
Media consisting of many different ingredients to fulfill growth requirements of organisms. On the other hand, fastidious organisms lack the ability to synthesize many of their substrates for the growth requirements. They must have an organic carbon supply to provide energy for the synthesis of cellular components and for the release of metabolic energy.
Complex Media
A medium where only pure chemicals in definite concentrations are used.
Synthetic Media
A medium in which the exact concentration and constituents of the chemicals used are not known with certainty. Also known as Undefined Medium.
Non-Synthetic/Crude Media
required for all biosynthesis leading to reproduction, product formation, and cell maintenance. In most fermentations, it also serves as the main energy source.
Carbon Sources
Under Saccharine, a byproduct of cane and beet sugar production.
Molasses
Under Saccharine, can be used as a source of carbon in the fermentation industries since they contain soluble sugars.
Fruit Juices
Under Saccharine, a major waste product of the cheese industry. It is a straw-colored liquid produced as a byproduct in cheese production .
Cheese Whey
Under Starches, classification of wheat, rice, barley
Cereals
Under Starches, classification of potatoes, tapioca, etc.
Roots & Tubers
Under Cellulosic, waste from paper pulp after the digestion process
Sulfite Waste Liquor (SWL)
Under Cellulosic, produced by acid hydrolysis of wood; produces 65-85% fermentable sugars
Wood Molasses
Under Cellulosic, a good source of cellulose
Rice Straw
Under Vegetable Oils and Hydrocarbons, oils obtained by de-oiling vegetable.
Vegetable Oil
Under Vegetable Oils and Hydrocarbons, used as fermentation substrates
Hydrocarbons
____ is required for the synthesis of protein, nucleic acid, and co-enzymes by microbial cells
Nitrogen Sources
What category is the Ammonium sulphate, Diammonium hydrogen phosphate, Ammonia, Urea
Inorganic
Under Organic, a byproduct of the corn wet-milling process
Corn Steep Liquor
Under Organic, the nutrieent-rich byproduct of potato processing
Potato Steep Liquor
Under Organic, a mixture of amino acids, peptides, water soluble vitamins and carbohydrates
Yeast Extracts
Under Organic, the material left after removing oil from the soya bean seeds
Soybean Flour
substances added to or simultaneously with the fermentation which are incorporated into the fermentation product, and which generally serve to increase the yield or improve the quality of the product
Precursors
those chemical compounds that when added to certain fermentations, more of a specific product may be produced, or a metabolic intermediate (which is normally metabolized) is accumulated.
Inhibitors
specific chemical compounds included in media which induce or provoke formation of desired industrial fermentation products
Inducers
surface active agents, reducing the surface tension in the foams and destabilizing the protein films by hydrophobic bridges between two surface, displacement of absorbed protein, and rapid spreading on the surface of the film
Antifoam Agents
depends on the specific type of fermentation process (aerobic/anaerobic).
Oxygen
before use, suspended solids, colloids, and microorganisms is usually removed, so a clean water with consistent composition is required.
Water
What is the microorganism that is one of the most common yeast strains used in fermentation. It is employed in the production of alcoholic beverages like beer, wine, and spirits.
Saccharomyces cerevisiae
What bacteria microorganisms are used in the fermentation of dairy products like yogurt and cheese, as well as in the production of sauerkraut and pickles.
Lactic acid bacteria, such as Lactobacillus and Streptococcus species
What fungi microorganisms are used in the fermentation of soybeans to produce soy sauce and tempeh, respectively.
Aspergillus and Rhizopus
The fermentation medium is prepared, usually containing a carbon source like glucose, lactose, or sucrose. Other nutrients, such as nitrogen sources, vitamins, and minerals, may be added to support microbial growth.
Preparation of raw materials
Specific microorganisms like yeast, bacteria, or mold are introduced into the fermentation medium. The choice of microorganism depends on the desired product, for instance, Saccharomyces cerevisiae for ethanol or Lactobacillus for lactic acid.
Introduction of microorganisms (Inoculation)
The microorganisms break down glucose or other sugars into pyruvate through ________. This process generates a small amount of energy (ATP) and intermediate compounds.
Glycolysis
Under anaerobic conditions, pyruvate is converted into specific byproducts based on the type of fermentation.
Fermentation Reaction
As fermentation continues, the byproducts accumulate in the medium. Some byproducts, like ethanol and organic acids, can inhibit microbial growth if their concentration gets too high.
Accumulation of fermentation products
Once fermentation is complete, the desired product is extracted from the fermentation broth. Common separation techniques include filtration, distillation (for alcohol), centrifugation, and crystallization.
Harvesting and Separation
The extracted product may undergo purification to remove impurities. Additional steps, such as drying, concentration, or chemical modifications, may be applied depending on the end-use application.
Purification and Post-Processing
Unused biomass and waste products are processed for disposal or recycling. Some byproducts like CO₂ and leftover yeast may be repurposed for other industries, like baking or biofuel production.
Waste Management and Recycling
Factors Affecting Fermentation Process:
- Substrate Quality
- Microbial Strain
- Temperature and pH
- Aeration and Mixing
- Sterilization
formed from pyruvate produced in glycolysis. NAD+ is generated from NADH.
Lactic Acid
Lactic acid is formed from pyruvate produced in glycolysis. NAD+ is generated from NADH. The enzyme lactate dehydrogenase catalyzes this reaction. Lactobacillus bacteria prepare curd from milk via this type of fermentation. During intense exercise, when the oxygen supply is inadequate, muscles derive energy by producing lactic acid, which accumulates in the cells, causing fatigue. It is used in making yogurt, sauerkraut, and pickles.
Lactid Acid Fermentation
This is used in the industrial production of wine, beer, biofuel, etc. The end product is alcohol and CO2. Pyruvic acid breaks down into acetaldehyde and CO2 is released. In the next step, ethanol is formed from acetaldehyde. NAD+ is also formed from NADH, utilized in glycolysis. Yeast and some bacteria carry out this type of fermentation. Enzyme pyruvic acid decarboxylase and alcohol dehydrogenase catalyze these reactions. It is used in beer, wine, and bread production.
Alcohol Fermentation
Vinegar is produced by this process. This is a two-step process. The first step is the formation of ethyl alcohol from sugar anaerobically using yeast. In the second step, ethyl alcohol is further oxidized to form acetic acid using acetobacter bacteria. Microbial oxidation of alcohol to acid is an aerobic process. It is used in vinegar production.
Acetic Acid Fermentation
This type of fermentation is characteristic of obligate anaerobic bacteria of genus clostridium. This occurs in the retting of jute fiber, rancid butter, tobacco processing, and tanning of leather. ____________ is produced in the human colon as a product of dietary fiber fermentation. It is an important source of energy for colorectal epithelium. Sugar is first oxidized to pyruvate by the process of glycolysis and then pyruvate is further oxidized to form acetyl-CoA by the oxidoreductase enzyme system with the production of H2 and CO2. Acetyl-CoA is further reduced to form butyric acid. This type of fermentation leads to a relatively higher yield of energy. 3 molecules of ATP are formed.
Butyric Acid Fermentation
Created through lactic acid fermentation, where bacteria like Lactobacillus and Streptococcus break down lactose (milk sugar) into lactic acid, causing milk to curdle and form ____. Different bacteria and aging processes contribute to various cheese flavors and textures.
Cheese
Made by fermenting milk with bacteria such as Lactobacillus bulgaricus and Streptococcus thermophilus. These bacteria convert lactose into lactic acid, thickening the milk and giving it a tangy taste.
Yogurt
Vegetables like cucumbers are fermented using lactic acid bacteria, which break down sugars and produce lactic acid. This process preserves the food and gives it a sour taste. Sauerkraut - a traditional German dish, and its name translates to “sour cabbage” in English. Sauerkraut is made by fermenting shredded cabbage with salt, which allows lactic acid bacteria to naturally ferment the cabbage’s sugars, creating a sour, tangy flavor and a longer shelf life.
Pickles
a traditional Indonesian food made from fermented soybeans, often used as a plant-based meat alternative, known for its chewy texture and nutty flavor.
Tempeh
typically made from malted barley, hops, water, and yeast. Other grains such as wheat, corn, or rice may also be used.
Beer
Beers generally have a lower alcohol content compared to wine and spirits, typically ranging from __ to __ alcohol by volume (ABV).
3% to 10%
brewed at higher temperatures with top-fermenting yeast
ales
brewed at low temperatures with bottom-fermenting yeast
lagers
a dark, rich beer made with roasted malts
stouts
made from fermented grapes, although other fruits such as apples (for cider) or berries (for fruit wines) can also be used.
Wine
Grapes undergo fermentation naturally with the aid of yeast present on the fruit’s skins. During fermentation, sugars in the grapes are converted into ___ and _____.
alcohol, carbon dioxide
Wines typically have alcohol contents ranging from __ to __ ABV, although this can vary depending on factors such as grape variety and winemaking techniques.
8% - 15%
Merlot, Cabernet Sauvignon, Pinot Noir
Red Wine
Chardonnay, Sauvignon Blanc, Riesling
White wine
Grenache Rosé, Zinfandel Rosé
Rose Wine
Campagne, Prosecco, Cava
Sparkling
Port, Sherry, Vermouth
Fortified wines
are distilled alcoholic beverages made from fermented grains, fruits, or vegetables. Common ingredients include barley, corn, rye, wheat, potatoes, and sugarcane.
Spirits
Spirits have higher alcohol concentrations compared to beer and wine, typically ranging from __ to __ ABV or higher.
20% - 60%
distilled from grains or potatoes
Vodka
from sugarcane juice or molasses
Rum
from malted grains and aged barrels
Whiskey
from grains and flavored with botanicals
Gin
made from blue agave plant in Mexico
Tequila
from fermented juice, usually grapes
Brandy
Production of antibiotics via fermentation
penicillin, streptomycin
Synthesis of vitamins
Vitamin C, Vitamin B12
Manufacturing of medical enzymes helps in diagnostics and treatments
glucose oxidase, thrombin
