Studies on the Degradation of Gluten Proteins During Germination of Wheat

摘要

Although the degradation of gluten proteins during germination has repeatedly been described in literature, no systematic studies on the degradation of single protein fractions and types under the same conditions of germination are available. Therefore, the aim of the present study was to investigate the enzymatic degradation of wheat gluten proteins depending on temperature and duration of germination. Wheat kernels were germinated for up to seven days at four different temperatures (15, 20, 25, 30°C). Samples of different stages of germination were taken and analyzed for their quantitative protein composition using a combined extraction/HPLC method. During germination the amount of protein decreased as a function of time. Glutenins were degradedfaster and to a higher extent as compared to gliadins. These differences in the degradation of gliadins and glutenins might be of great interest particularly with regard to using germinated wheat kernels for breadmaking. Within each fraction, protein types were affected to a different extent. Differences were also observed in the degree of degradation as a function of temperature. For example, the omega-gliadins were degraded faster at 20 °C and the a-gliadins faster at 30 °C.