五倍子单宁对啤酒稳定性的影响

EFFECT OF VEGETABLE TANNINS ON BEER STABILITY

单宁是植物的次生代谢产物。酿酒时单宁从大麦和酒花转入啤酒 ,成为啤酒的重要成分。大麦单宁为缩合单宁 ,以原花色素的二聚体、三聚体为主。在糖化和洗糟时低聚的原花色素因氧化聚合成高分子单宁而急剧减少。酒花单宁由水解单宁、缩合单宁构成 ,其中含有活泼羟基的花色苷和类单宁能延迟啤酒老化口味的产生和提高胶体稳定性。五倍子单宁是中国特有的资源 ,添加五倍子单宁 6g/ 10 0L于麦汁和啤酒中 ,可降低麦汁中高分子区分氮 5mg/ 10 0mL ,减少双乙酰的生成 ,使啤酒胶体稳定性和口味稳定性得以提高。

Tannin, which is a secondary metablite of plants and gets into beer from barley and hop in processing of beer,is an important ingredient in beer.Tannins in barley are condensed tannin consisting chiefly of dimeric and trimeric proanthocyanidins.In the process of saccharification and elution,the content of these oligomeric proanthocyanidins is reduced abruptly through oxidization into polymeric tannins.Tannins in hop consist of hydrolyzable tannins and condensed tannins,containing anthocyanin and odies tannins which inhibit muddy and improve colloidal stability of beer.Chinese gallotannin is hydrolyzable tannin.When Chinese gallotannin is put into wort and beer at 6?g/100?L,the macromolecular nitrogenous substance is reduced 5?mg/100?L in wort,the formation of diacetyl is also reduced,and the colloidal stability and flavour stability of the beer are improved.