Biotechnology and the Brewing Industry

For the first 5,000 years that humans made and consumed beer, little was known about the actual scientific principles involved in its manufacture. Beer making was an art, practiced by craftsmen. Only in the last 150 years have biochemists and microbiologists identified the relevant organisms and metabolic pathways involved in the beer fermentation. In the past ten years alone, the entire genome of Saccharomyces cerevisiae (albeit, a lab strain, not an actual brewing strain) has been sequenced,...

Trickling generator processes

In the vinegar fermentation, the rate at which ethanol is oxidized to acetic acid depends on the presence and availability of oxygen and the surface area represented by the air-liquid interface. In other words, the ability of acetic acid bacteria to perform the acetic acid fermentation is limited primarily by the diffusion or transport of oxygen from the atmosphere to the cell surface. It is possible to significantly accelerate the oxidation of ethanol by increasing the surface area to which...

Propionic Acid In Hops

Proton Translocating Atpase

In the final step prior to fermentation, the wort is pumped into a special heating tank called the brew kettle. It is here that the wort is boiled and other important reactions occur.Be-fore the wort is heated, however, one more essential beer ingredient, hops, is added to the wort. Hops are derived from the plant Homu-lus lupulus in the family, Cannabinaceae , and although they were not part of the original beer formula, they have been added to beer since the Middle Ages. Why hops came to be...