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Note: The scientific names of the specific microorganisms mentioned in the video are not italicized because of the video application's feature limitations.
Here are the scientific names in the video that are supposed to be italicized.
1. Saccharomyces cerevisiae
2. Acetobacteriaceae
3. Gluconobacter
4. Acetobacter

Attached here is the complete discussion of the topic.


Vinegar is the product made from the conversion of ethyl alcohol to acetic acid by a genus of bacteria, Acetobacter.

Microorganisms involved in the vinegar production
1. Yeast
2. Acetic Acid Bacteria

Yeast (Saccharomyces cerevisiae)
Yeasts are ‘unicellular ascomycetous or basidiomycetous fungi, whose vegetative growth result predominantly from budding or fission’. They are the main component used in alcoholic fermentation they speeds up the fermentation process. Yeasts had high tolerance to acidity that facilitated their survival and growth in fruit juices that have pH values below the tolerance level for several other microorganisms. The YEAST is responsible for the alcoholic fermentation and AAB is for the acetification.

AAB
AAB are classified the acetic acid bacteria (AAB) in the family Acetobacteriaceae and Gluconobacter.
AAB are Gram-negative or Gram-variable bacteria, with ellipsoidal to rod-shaped morphologies, being motile due to the presence of flagella, which could be either peritrichous or polar.
AAB are present in the environment and in the raw material, but they cannot grow during alcoholic fermentation because of the anaerobic conditions. When the alcoholic liquid was exposed to oxygen, the AAB started their growth on the surface.

VINEGAR PRODUCTION

Supposed we have coconut substrate as our flavor. The first step would be, the fermentable sugars are transformed into ethanol by the action of yeast in the name of Saccharomyces cerevisiae. In the second step, Acetic Acid Bacteria oxidizes the ethanol into acetic acid in an aerobic process.

CHEMICAL FORMULATION

Initially, alcohol is hydrogenated to form acetaldehyde. In the second step, hydrogen ions bind with oxygen to form water that hydrates acetaldehyde to form aldehyde.

During third step, aldehyde dehydrogenase converts acetaldehyde to acetic acid and releases hydrogen.

USES OF VINEGAR

Whether naturally produced during fermentation or intentionally added, vinegar retards microbial growth and contributes sensory properties to a number of foods. It has been used as a medicine, corrosive agent, pickling agent and can be directly consumed in diluted form as a beverage. In the food industry, vinegar is used mainly as an acidulant.

Vinegar is found in hundreds of different processed foods, including salad dressings, mayonnaise, mustard, ketchup, bread and bakery products, canned foods, marinades and the current falling wine consumption have favoured an increase in vinegar production.