Milling, water uptake, and modification properties of different barley (Hordeum vulgare L.) lots in relation to grain composition and structure.

Milling properties, water uptake, and modification in malting were studied in 14 barley (Hordeum vulgare L.) lots from two consecutive crop years. In all barley lots studied, grains with lower β-glucan and protein content and higher starch content produced finer flours upon milling. Grains with lower β-glucan content also hydrated more rapidly during steeping. A detailed study of two cultivars from two crop years indicated that similar environmental conditions could induce a higher β-glucan content and concentration of aggregated B hordein in the peripheral endosperm and a lower proportion of C hordein entrapped among aggregated hordeins deeper within the endosperm. These characteristics were associated with production of coarser flours during milling as well as with slower water uptake and lower modification. However, the data do not distinguish between the effect of β-glucan content and that of hordein localization. Distribution of β-glucan or total protein within the kernel was not linked to hydration or modification.