啤酒是以麦芽为主要原料,经过糖化发酵后不经蒸馏而制成的饮料,有鲜熟之分。鲜啤酒含有鲜酵母,味鲜美,但保存期短;熟啤酒虽不含鲜酵母,保存期较长,但最好不超过三个月。从颜色上看,有浓淡之分。浓色啤酒又称黑啤酒,浅黑色,味浓醇;淡色啤酒一般呈淡黄色,透明度较好。啤酒中酒精的含量约在4—6%左右。啤酒的卫生标准规定感官指标应呈澄清液体,无沉淀及杂质,无异臭及异味。理化指标,二氧化硫残留量以游离SO_2计按g/kg≤0.05,黄曲霉毒素B_1按Ug/kg应≤5,细菌指标,生啤酒大肠菌群按个/100 ml计应≤50;熟啤酒细菌 Beer is malt as the main raw material, after saccharification and fermentation made without distillation of the beverage, there are ripening points. Fresh beer contains fresh yeast, delicious, but short shelf life; cooked beer although does not contain fresh yeast, longer shelf life, but preferably not more than three months. From the color point of view, there are shades of distinction. Color beer, also known as dark beer, light black, taste rich alcohol; light beer generally pale yellow, better transparency. The content of alcohol in beer is about 4-6%. The hygienic standard of beer provides sensory indicators should be clear liquid, no sediment and impurities, no smell and odor. Physical and chemical indicators, residual SO2 to free SO_2 by g / kg ≤ 0.05, aflatoxin B_1 by Ug / kg should be ≤ 5, bacterial indicators, draft beer coliform bacteria per / 100 ml should be ≤ 50; cooked beer bacteria