Gluten viscoelasticity: Rapid method for classification of soft-like wheat genotypes

Background and objectives Standard empirical methods to assess wheat quality are difficult to perform, interpret, time consuming and require a large amount of sample. A rapid uniaxial compression instrument based on measuring height of gluten during compression and recovery is reported. The objective of this study was to determine in a set of soft-like wheat genotypes from Brazil the best conditions to extract the gluten and analyze the efficiency of the method separating categories based on gluten viscoelastic properties. Findings The independent variables evaluated were as follows: (a) technological quality categories and gluten extraction method; (b) amount of 2% NaCl solution (w/v) added for dough formation; (c) mixing time; and (d) washing time. The results were submitted to analysis of variance and means compared by protected LSD test (p < 0.05). The best conditions for gluten extraction and analysis were obtained with 4.4 ml of 2% NaCl solution, mixing for 20 s, and washing for 3 min. Elastic recovery of gluten showed a strong correlation (r) with standard methods used to classify wheat (dough strength r = 0.988, stability r = 0.963). Conclusion The elastic recovery was able to separate the gluten samples in three categories efficiently and may be a useful tool in breeding programs and flour mills quality control. Significance and novelty: A novel method for determining elastic recovery of gluten from soft-type wheat genotypes was developed. The set of samples had high correlation of gluten elastic recovery with key quality parameters. Advantages of the test include rapid analysis time (less than 5 min) and small sample size (10 g of flour).