Effects of abiotic stress and crop management on cereal grain composition: implications for food quality and safety

Abstract

The effects of abiotic stresses and crop management on cereal grain composition are reviewed, focusing on phytochemicals, vitamins, fibre, protein, free amino acids, sugars, and oils. These effects are discussed in the context of nutritional and processing quality and the potential for formation of processing contaminants, such as acrylamide, furan, hydroxymethylfurfuryl, and trans fatty acids. The implications of climate change for cereal grain quality and food safety are considered. It is concluded that the identification of specific environmental stresses that affect grain composition in ways that have implications for food quality and safety and how these stresses interact with genetic factors and will be affected by climate change needs more investigation. Plant researchers and breeders are encouraged to address the issue of processing contaminants or risk appearing out of touch with major end-users in the food industry, and not to overlook the effects of environmental stresses and crop management on crop composition, quality, and safety as they strive to increase yield.

Keywords: Climate change; crop nutrition; drought; food safety; food security; grain composition; heat stress; processing contaminants; regulatory compliance..

Fig. 1.

Top: upland rice growing in a field trial at Shanghai Academy of Agricultural Sciences, Shanghai, China during a period of extreme temperature and drought in August 2013. Bottom: rice grown in a farm of Hainan province (China) in 2010, showing the leaf rolling and white spike phenotypes brought about by drought stress (kindly provided by Professor Hanwei Mei, Shanghai Agrobiological Gene Centre).

Fig. 2.

Diagrams representing the structures of acrylamide, furan, and hydroxymethylfurfuryl

Fig. 3.

Free asparagine concentration in the grain and acrylamide formation in wholemeal flour (heated for 20min at 170 °C) for wheat cv. Alchemy grown at Brockhampton, Herefordshire, UK in 2009–2010 with different rates of sulphur application (data from Curtis et al., 2014a ).