Genetic analysis of barley for Shochu quality

Abstract

Malting barley is a primary ingredient for barley Shochu, a Japanese traditional spirit. The production process of barley Shochu consists of the pearling operation where the outer layer of barley kernels is removed and the fermentation process where the pearled barley is fermented and distilled. Due to the labour-intensive nature of the conventional evaluation, a more simple and rapid method is required to assess the suitability of malting barley varieties for Shochu purposes. The present study was conducted to identify genetic regions responsible for barley Shochu quality in an effort to develop a marker-assisted selection method. A doubled haploid population generated from a Commander/WI4191 cross was tested for pearling suitability and flavour component levels in the mash and Shochu, and QTL analysis was performed across two consecutive years using the Shochu quality data sets and a 2531-point linkage map. As a result, consistent QTL for pearling yield were detected on chromosome 1H, which were considered to be a possible selection tool. Fourteen QTL were associated with seven flavour compounds in the mash and Shochu.