Effect of Common Natural Preservatives on the Shelf Life of Fresh Beer

In order to effectively extend the shelf life of fresh beer, lysozyme, protamine, phytic acid, tea polyphenols, sodium D-isoascorbate, glucose oxidase, nisin and natamycin were added into fresh beer as natural preservatives. The fuzzy matrix evaluation system combined with microbiological and physicochemical indexes integrated analysis and observation of the number of microorganisms in fresh beer by trinocular microscope was used to screen the natural preservatives that was more effective in extending the shelf life of fresh beer on the premise of stable beer quality. The results showed that the addition of 0.3 g/L lysozyme, 0.002 g/L glucose oxidase, or 0.03 g/L nisin could effectively extend the shelf life of fresh beer with stable quality.