Phenolic compounds in alcoholic and low-alcoholic beer by fast HPLC-PDA-MS/MS analysis: impact of malt composition, hops and dealcoholization process.

Beer is one of the most consumed beverages worldwide, whose market is constantly increasing. In addiction a side-market of alcohol-free and low-alcohol beer is fast growing, with a consequent strong demand of technologies with a minimum impact on organoleptic and nutritional properties. Polyphenols from malts and hops are the main antioxidants in beer, that affect flavor, color and stability, besides being considered responsible for health benefits. Our recent research aimed to provide a method for the fast analysis of phenolic profile and content, and to investigate the suitability of membrane-based dealcoholization processes. So, we developed a method to fill the need for analysis without samples pretreatments, based on HPLC-PDA-MS/MS in SIR mode [1]. The method, as also assays for total phenolic content, antioxidant activity or NMR investigation, was applied to craft beers differing in the recipe (India Pale Ale, Amber Ale and American Pale Ale, IPA, ALE and APA, respectively) [1] and in malt compositions (Pale Ale with increasing percentage of dark malt, PA100 and PA85, respectively) [2]. The last ones were dealcoholized by osmotic distillation and analyzed (LA100 and LA85, respectively) [2]. A commercial alcoholic beer (AB) was used to investigate a new cascade process: the first diafiltration step was first studied by using two different membranes (cellulose, LAB1, and polyacrylonitrile, LAB2), and the phenolic content was analyzed [3]. Some results of phenolic content (mg/L) are resumed in the Table.