Relationships between fatty acid contents of barley grain, malt, and wort with malt quality measurements

Although lipids and fatty acids (FA) represent only 1-3% of the grain weight, they can play an important role in regulating, modulating, and determining several chemical and physical properties of the grain and corresponding malts. The aim of this study was to evaluate the relationships between the content of FA in grain, malt, and wort with malt quality characteristics such as hot water extract (HWE) and apparent attenuation limit (AAL) in different commercial malting barley varieties. High and positive correlations were found between myristic acid and HWE (r = 0.71) and between stearic acid and AAL (r = 0.76), with intermediate correlations between palmitic, oleic, linoleic, and linolenic acids and AAL (r = >0.50) in grain. High and negative correlations were found between stearic acid and HWE (r = -0.66), and high and negative correlations were found between palmitic (r = -0.74) and linoleic (r = -0.60) acids and AAL in the wort. Results from this study showed that lipids, as well as the combination of unsaturated and saturated FA, might play a role in determining differences in HWE and AAL between the barley varieties analyzed. No clear evidence on HWE was observed when grain and malt samples from the same variety were compared. These results indicated that lipids and FA should be considered together with starch properties to explain differences between HWE and AAL.