Folate in barley grain and fractions

Wholegrain cereals are good sources of folate. However, little is known about folate in barley. In this study, total folate was analysed in five hulled Finnish barley cultivars from three harvesting years (2006–2008). In addition, different fractions were produced from two hulled cultivars by scarification and from mixes of hulled cultivars by industrial milling. Total folate was determined in all samples with a microbiological method and vitamer distribution in scarification and industrial milling fractions, using HPLC or UPLC. Limited variation was observed in the total folate content of the five cultivars. The average contents of the three harvest years ranged from 563 to 773 ng/g dm. Fractions containing germ and outer layers were the richest in folate. The highest total folate content in the scarification fractions was up to 1710 ng/g dm. The total folate content of the hull fraction obtained by dehulling 10% of the grains with an industrial pearler was almost 4-fold compared to the corresponding dehulled grain. This hull fraction is normally not used as food. The main folate vitamers in the fractions were 5-HCO-H₄folate, 5-CH₃-H₄folate, 5,10-CH⁺-H₄folate, and 10-HCO-PGA. Folate content could be enhanced naturally by introducing folate-rich fractions of barley into cereal products.