Beverages Juice, Soft Drinks, Wine, and Beer

Fruit juice, beer, wine, and liquor – many of our beverages are based on plant ingredients. Neither the plants themselves, nor the yeasts used in alcoholic fermentation are genetically modified. Nonetheless, many beverages are produced using enzymes made with the help of genetically modified microorganisms.

Alcoholic Beverages. Whether it’s wine, beer, or spirits, alcoholic fermentation is the fundamental metabolic process behind every alcoholic beverage. Yeasts break down plant starches into simple sugars, which are then converted into alcohol (ethanol). Secondary metabolic products help give alcoholic beverages their characteristic aromas and flavours.

Red wine: A stable colour and full aroma are made are possible by enzymes. Some wine makers use enzyme supplements. Fruit juice. Enzymes improve the efficiency of juice extraction and break down substances that cause cloudiness. Beer from Bt maize. A beer from Bt maize is brewed in Sweden (Kenth). A similar beer is availible in Switzerland (Cool Corn).

Plants. Plant materials provide the starch for metabolic fermentation. These may be wine grapes (wine), barley, wheat, maize (beer, spirits), potatoes, and fruit (spirits, liqueurs). None of the plants that are used as starch sources for alcoholic beverages have commercially grown genetically modified varieties. The one exception to this is maize, which is sometimes used for brewing beer. Yeast. None of the yeast strains commercially used in alcoholic fermentation are genetically engineered. No GM yeast strains have been approved in any country, and this is not likely to change any time soon. At one time hopes were high that genetically modified yeast could open new possibilities for alcoholic fermentation. Several research projects were aimed at improving brewing processes to produce low-calorie or low-alcohol beers. Despite several attempts, these efforts have not panned out. Enzymes. The breakdown of starch, the fermentation of sugars, and the formation of characteristic secondary metabolites are all driven by enzymes. These enzymes naturally occur in raw plant materials or are produced by yeast. Sometimes, however, processes can be optimised by adding isolates of essential enzymes. Many of these are produced with the help of genetically modified microorganisms. In beer brewing, supplemental enzymes can accelerate malting, suppress off-flavours, or degrade residues. In wine, they can improve juice recovery during pressing or can adjust the development of flavours and aromas. In spirits, they improve the breakdown of starch and carbohydrates. The use of supplemental enzymes in beer is not permitted in Germany.

Juices. Enzymes can increase the efficiency of juice extraction by digesting starches and cellulose, a tough compound that is found in plant cell walls. After pressing, fresh juice retains enzymes that break down cloudy, starchy residues. Many of these useful enzymes can now be produced with the help of genetically modified microorganisms.

Juices are sometimes fortified with vitamins or sweetened with artificial sweeteners for diabetics. Some of these additives are produced with the help of genetic engineering.

Soft Drinks. Cola and other soft drinks contain several ingredients and additives that are sometimes produced from GM maize or with the help of GM microorganisms.

• Glucose syrup (corn syrup), glucose, and other products derived from starch can be made from GM maize.

• Colourings like beta-carotene and riboflavin, vitamins, citric acid, and the sweetener aspartame can all be produced with the help of genetically modified microorganisms.

See also on GMO-Compass:

• GM microorganisms produce additives, vitamins, enzymes and amino acids.