Cold mash in brewer wort with low carbohydrate content: a study of the mashing step

Abstract

Cold mash is an innovative and promising brewing technique for obtaining free-alcohol and low-alcohol beers, with a sensory profile similar to traditional beers. While traditional mashing is carried out at high temperatures, between 50 and 75 oC, this technique uses low temperatures, around 10 oC, but with a longer time. This allows more intense extraction of flavors and color from the malt while keeping the concentration of fermentable sugars low, as the enzymatic starch hydrolysis does not occur at its maximum efficiency. A study was performed on the mashing stage of the brewing process using the cold mash technique, with subsequent physicochemical characterization, to evaluate possible changes in these parameters. To obtain beer worts with low concentrations of fermentable sugars, modifications were made to mashing temperature and time, and a two-level factorial design was applied to evaluate the influence of these variables, demonstrating that the main factor mashing time was of great importance in the response. The extract content, related to the concentration of carbohydrates, presented results around 6 oBx, while the traditional wort has between 11 and 12 oBx, and the protein content was 0.12 to 0.13%, being below than reported in the literature. For pH, the results were around 6.0, which is above the recommended for brewer's wort, demonstrating that the mashing technique employed promoted changes in this parameter, possibly due to the limited action of the phosphatase enzyme, responsible for lowering the pH through the production of phosphoric acid.