• Korean Journal of Food Science and Technology
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• v.40 no.3
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• pp.360-363
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• 2008

Two barley malt samples were selected at two different stages of germination, a well-modified malt germinated for 96 hr and a poorly-modified malt for 60 hr, and were analyzed for total, insoluble, and soluble ${\beta}$-glucan contents. The total ${\beta}$-glucan content in raw barley was 3.96%, and the content was reduced during malting. The total ${\beta}$-glucan contents of the poorly- and well-modified malts were 1.02% and 0.18%, respectively. After 4 days of germination, approximately 95% of the ${\beta}$-glucan present in the barley was degraded. A significantly higher proportion of water-soluble ${\beta}$-glucan was found in the well-modified malt, suggesting that ${\beta}$-glucan solubility was dependent on cell wall modifications in the malt (${\beta}$-glucan breakdown). The proportion of water-soluble ${\beta}$-glucan was also affected by the extraction temperature. The two differently modified malts were mashed isothermally at 45, 55, 65, and 75oC for 2 hr. An increasing mashing temperature resulted in increased viscosity for the wort and the resulting beer. The viscosity of the wort from the well-modified malt was significantly low, due to its low initial malt ${\beta}$-glucan with increased solubility as well as a presumably sufficient ${\beta}$-glucanase activity during mashing.