Why craft beer needs to be fermented

In order to obtain craft beer with excellent taste and taste, every brewing process requires us to do it with our heart. So it is necessary to understand each process, such as how beer is fermented.

The significance of craft beer fermentation

Craft beer fermentation is through the action of beer yeast to convert the fermentable sugar in the wort into alcohol and carbon dioxide, and release heat at the same time.

Role of fermentation (two utilizations, two productions)

Two exploits:

(1) Brewer's yeast uses wort fermentable sugar as carbon source for respiration and fermentation;

(2) Brewer's yeast uses low-molecular-weight nitrogen in wort as a nitrogen source for reproduction.

Two builds:

(1) Generate main metabolites—alcohol and carbon dioxide;

(2) Generate other metabolites—higher alcohols, aldehydes, esters, diacetyl, sulfides, acids, etc.

These products determine the quality of craft beer: taste, flavor, foam, non-biological stability, etc.

Carbohydrate metabolism in wort

Carbonated compounds account for about 90% in wort, mainly

1. The sugars in wort are divided into fermentable sugars—glucose, fructose, sucrose, maltose, and maltotriose;

2. Non-fermentable sugar - low molecular weight dextrin and other carbohydrates.

Carbohydrate metabolism refers to the process by which these sugars are broken down under aerobic and anaerobic conditions.

Formation and effects of by-products during fermentation

(1) is an intermediate or final product of the transformation of yeast substances;

(2) have beneficial or adverse effects on the smell and taste of craft beer;

(3) Diacetyl, higher alcohols, esters, aldehydes, organic acids and sulfides, etc.

Raw green flavor

(1) Diacetyl, aldehyde, sulfide;

(2) Let craft beer present immature aroma and taste;

(3) The content can be reduced through biochemical and technical means.

Aromatic

(1) Esters and higher alcohols;

(2) One of the components that determine the aroma of craft beer is beneficial within a certain range, but excessive will be very unfavorable;

(3) It is difficult or impossible to separate from craft beer by technical means.

Whether it is craft beer or ordinary beer, it needs to be fermented.