GB1015831A - Improvements in or relating to methods and composition of chillproofing - Google Patents

Abstract

In order to test whether or not an extract of a fungal micro-organism is suitable for the satisfactory chillproofing of beer, samples of beer are treated with the extract, and the amount of chillhaze in the samples is determined and compared with the amount of chillhaze in similar samples similarly treated with a standard chillproofing formulation. A preferred procedure involves storing fermented but unchillproofed beer in the cold and protected from exposure to air, filtering, carbonating and bottling the beer, removing air from and sealing the bottles, introducing the fungal extract under test into the bottles (this involves opening the bottles and re-sealing them), pasteurizing, storing in the cold, determining the amount of chillhaze in the bottles and comparing this with the amount of chillhaze in similar bottles similarly treated with a standard chillproofing formulation. The following fungal micro-organisms are suitable: Aspergillus niger, Aspergillus awamoris, Aspergillus usami and Aspergillus phoenicius. The following fungal micro-organisms are stated to be unsuitable: Aspergillus oryzae, Aspergillus wentii, Mucor delamar, Amylomyces rouxii, Penicillium oxalicum, Penicillium casei and Penicillium janthinellum. The aqueous extract of the fungal organism is preferably treated to inactivate limit dextrinase, as by lowering the pH temporarily to 1.5-2.0. The suitable fungal extracts may be employed in synergistic combination with such chillproofing proteolytic enzymes as papain, ficin, pinguinain and bromelain. According to an example, a wheat bran mash is prepared from wheat bran, wheat flour and water, and is sterilized. About 125 g. of the sterile mash is inoculated with an actively growing culture of Aspergillus niger, After suitable growth at 30 DEG C., the resultant bran-growth product is dried at low temperature. About 10 parts by weight of water is then mixed with the bran-growth product with continuous stirring or shaking for about an hour. Liquor expressed from the wet bran by pressing, centrifuging or filtering, is tested, either directly or after concentration, as to its suitability for satisfactorily chillproofing beer, by a comparison of turbidity measurements on beer thus treated with those obtained employing papain of a known activity in various concentrations. The fungal chillproofing extracts may be added to fermented beer as it goes into storage, or to wort before, at the commencement of, or during fermentation, or a portion may be added to the fermenter and a second portion added to the fermented beer. Concentrations of 1-2 lbs. of the fungal extract per 100 barrels of beer are suitable. When employing the combination of papain and the fungal extract, it is possible to reduce the amount of papain from 1 lb. to about 1/3 -\ba1/2 lb. per 100 barrels, and the amount of fungal extract to only one-third or one-half of the normal amount required as the sole chillproofing agent.