Abstract
Differences in kernel texture are mainly caused by specific secaloindoline (SIN) proteins occurring in friabilin fraction of hexaploid triticale (×Triticosecale Wittmack) grain. SINs were isolated using Triton X‐114 partitioning from either kernels/flour or starch of five triticale cultivars with wide range of different hardness. Crude SIN fraction was obtained by size‐exclusion HPLC. SINs were separated on an uncoated fused‐silica capillary using the iminodiacetic (IDA) buffer in conjunction with lower‐concentrated poly(ethylene oxide) and ACN. A low‐concentrate mixture of hydrophilic polymers, PVP and hydroxypropylmethylcellulose in IDA buffer was employed for dynamic coating of capillary inner wall. In total, on the basis of CZE profiles, two SIN‐a proteins and two SIN‐b proteins were identified. Allelic forms SIN‐a1 and SIN‐b1 have both two soft and one medium hard genotypes, however other allelic forms, designed as SIN‐a2 and SIN‐b2, were identified in hard and other medium hard cultivars. The CZE profiles showed that the ratio of the peak areas of SIN‐b proteins isolated from triticale starch can be preliminarily used to distinguish cultivars with soft and hard grain.