Brewing trials with spring and winter barley varieties

Abstract

Mikyška A., Psota V., Hrabák M. (2012): Brewing trials with spring and winter barley varieties. Czech J. Food Sci., 30: 27-34.The effects of a set of barley varieties on the brewing process and quality of beer production intermediaries were studied in trial brews (40 l) prepared using the two-mash decoction process. The varieties included in the trial were selected based on the starch granule size distribution determined previously. A significant effect of the varieties on the saccharification time of both mashes was determined. The highest saccharification rate in brews was achieved with the variety Jersey; the saccharification time of the 1 st and 2 nd mash with the variety Tiffany was markedly longer.The varieties with a greater fraction of large starch granules (Tiffany and Luxor) exhibited a higher haze with sweet wort as well as hopped wort compared to the varieties with a low fraction of large starch granules (Jersey and Tolar). The effect on the lautering time was not demonstrated. Pronounced varietal differences were determined in the extract balance of the brewing process. The varieties Tiffany and Luxor exhibited significantly lower extract yields. The malts from these varieties had lower laboratory extracts and higher extract losses in spent grains. The effect of the variety on the sacharide composition in hopped wort was confirmed. The proportion of fermentable saccharides in hopped wort extract rose from the variety Tiffany (66.9%) to the variety Jersey (83.6%). A significant difference in the final attenuation was also determined (76% in beers prepared from the varieties Tiffany and Luxor compared to 81.5% from the Jersey variety).