Simple tests as tools for vital wheat gluten evaluation

Abstract

PurposeThe purpose of this paper is to evaluate the viscoelastic quality of commercial vital wheat glutens from different origins (A and B) through simple tests, and correlate these results with dough rheological parameters measured using more complex equipment (farinograph and extensograph) and with bread quality characteristics (specific volume and crumb firmness) obtained from wheat flour fortified with 7 g/100 g of vital gluten.Design/methodology/approachFor the evaluation of vital gluten quality, two commercial vital wheat gluten named A and B were used. The simple tests performed with these samples were wet and dry gluten contents and index gluten, extensbility test and expansion test. The Pearson correlation was performed among data from dough rheological tests (farinograph and extensograph) and bread quality parameters (specific volume (SV) and crumb firmness) obtained from the fortification of wheat flour with 7 g/100 g of VGA or VGB (previous work, data not shown).FindingsThe simple tests showed differences in the viscoelastic properties of vital gluten A and B; vital gluten A presented higher elasticity and lower extensibility than vital gluten B, and the gluten ball of sample A presented higher SV. By correlation analysis, it was verified that the simple tests studied may be useful to assess the baking performance of commercial vital gluten when this product is added to wheat flour for its fortification. Furthermore, the results indicate the need for more information on vital wheat gluten proteins for its commercialisation and use.Originality/valueThis work is very important, not just for the scientific community, but also for the bakery industry, that requires more information about vital wheat gluten before its use in bread making. As there are great differences in the protein quality of commercial vital wheat glutens and their functionality, the study was developed to solve this problem.