Volatile Organic Compounds of Whole‐Grain Soft Winter Wheat

Abstract

Cereal Chem. 94(3):594-601The aroma from volatile organic compounds (VOC) is an indicator of grain soundness and also an important quality attribute of grain foods. To identify the inherent VOC of wheat grain unaffected by fungal infestation and other extrinsic factors, grains of nine soft wheat varieties were collected at various days postanthesis (DPA) and analyzed for VOC. Ten VOC were detected in all nine varieties at all DPA. 3-Methyl-1-butanol, 2-methyl-1-butanol, 1-pentanol, hexanal, and 1-hexanol were the predominant VOC in concentration. The VOC concentration generally decreased as grain matured from 25 to 40 DPA. Hexanal and 1-hexanol were the most abundant VOC in five and four varieties at 1.30-2.99 and 1.21-5.46 µg/kg of wheat grain, respectively, at 40 DPA. The VOC profiles of wheat grains infected with fungal diseases and stored for several months were uniquely different from that of sound grain.

Effects of processing on the phenolic contents, antioxidant activity and volatile profile of wheat bran tea

“…In the raw wheat bran, high concentration of 1‐hexanol was detected (Table ), which is in consistent to the literature that 1‐hexanol is the main alcohol in wheat (Ji et al ., ). This alcohol compound has a green and herbal aroma (Table ).…”

“…Amongst all esters, methyl hexanoate was the most abundant. 2‐Pentyl‐furan was detected in raw wheat bran, which was also reported in whole wheat with a fruity and green aroma (Ji et al ., ). It was reported that whole wheat flour had a significantly higher level of 2‐pentyl furan compared to the refined wheat flour (Moskowitz et al ., ), indicating it mainly existed in the bran.…”

“…Two alkanes, nonadecane and heneicosane were detected in this studied material, which were also previously reported in wheat by Zhang () and Ji et al . ().…”

“…Nonanoic acid was the only carboxylic fatty acid detected in the raw wheat bran. It is commonly found in the lipid layer of grain with a waxy and fatty scent (Ji et al, 2017). Alkane is frequently reported in raw wheat, but do not contribute to the aroma profile due to its high odour detection threshold (Hui, 2007).…”

Micro‐organisms growing on rapeseed during storage affect the profile of volatile compounds of virgin rapeseed oil

“…The result of uncontrolled growing of fungi often is a colour shift to a green–yellowish hue with higher lightness and an approxoimately 1000‐fold increase in colony‐forming units per seed mass . It is also known from other raw materials or food products that fungi result in a change of the volatile profile . A correlation between fungi settlement and changes of the volatile profile of rapeseed or the resulting rapeseed oil has yet not been carried out.…”