Effects of grain storage time and storage temperature on flour quality parameters of “5 + 10” wheat cultivar and “2 + 12” wheat cultivar

Backgrounds and Objectives Physicochemical changes that take place inside the wheat kernel during storage make the quality stable. Storage temperature will affect the different mechanisms of changes. The newly harvested “2 + 12” wheat cultivar (H4399) and “5 + 10” wheat cultivar (XM26) grains were stored under ambient temperature and 4°C for 120 days, respectively, and sampled for grinding every 30 days. Findings With the extension of storage time, the content of crude protein and glutenin macropolymer (GMP), Gʹ and G" of GMP gel, maximum resistance, and extensibility of both varieties increased to higher value and then decreased slightly. The higher value appeared at 90 or 120 days under ambient temperature, and at 30 or 60 days under 4°C, approximately 30–60 days earlier than under ambient temperature. During storage, the relative increasing of protein and GMP content, sedimentation index, G", tan δ, stability, maximum resistance, and extendibility of dough of “2 + 12” wheat cultivar (H4399) were bigger than “5 + 10” wheat cultivar (XM26). The relative increasing of Gʹ, water absorption, development time of dough were smaller than “5 + 10” wheat cultivar (XM26). Conclusions It is concluded that low‐temperature storage can accelerate protein aggregation in wheat grains and shorten the time to steady state. Increasing in GMP stiffness and dough development time is more sensitive to postharvest storage in a “5 + 10” wheat cultivar (XM26) versus a “2 + 12” wheat cultivar (H4399). Significance and Novelty The changes of protein physicochemical properties of different varieties under different storage conditions explained the main mechanism of protein aggregation during wheat storage.