Sensory properties of wheat varieties being ignored

The study​, published in the Journal of Cereal Science​, shows different varieties of wheat can significantly impact the appearance, texture, taste and smell of bread. Future wheat breeding and selection programmes should take this into account, suggest authors María Jesús Callejo, María-Eugenia Vargas-Kostiuk and Marta Rodríguez-Quijano.

“Until now, wheat sensory properties have not been systematically included as quality parameters in the selection of new wheat varieties… Based on the results of this study, we propose that sensory properties should be considered as breeding criteria for future work on genetic improvement​,” said the study’s conclusion.

Callejo said: “The selection of raw materials, considering the organoleptic characteristics that they can provide to the bread, could increase the diversity of final products. This point is very interesting, to create a range of high-quality bread products similar to other food sectors such as wine or oil​.”

Spelt for choice​

The researchers set out to test whether the use of different varieties of spelt wheat would have an effect on the properties of resulting loaves of bread. They looked at spelt because of the growing interest in the varietal, thanks to its perceived health benefits, despite the challenges in both growing and processing the grain.

In order to achieve a fair test, the team created strict protocols for both the creation and evaluation of the breads. They selected five different varieties of wheat – two spelt, three bread wheat – all grown in the same region, under the same conditions, harvested at the same time, and milled in the same way, before baking loaves of bread according to the same recipe and process.

For the evaluation, the researchers trained 18 people over four months, training and assessing them for their ability to distinguish consistently between different attributes of bread, across a variety of different tests. Finally they selected a panel of nine, for the final evaluation of the test breads, in the process creating a training protocol they hope could be used in future studies.

Significant differences​

“The tactile texture attributes and most of the appearance attributes were significantly different between breads. Significant differences were found between the spelt breads and those made with bread wheat for the attributes ‘crumb cell homogeneity’ and ‘crumb elasticity’. Considering the odour and flavour attributes together, the bread made with ‘Espelta Navarra’ was the most complex, from a sensory point of view​,” said the study.

Interestingly, while the spelt breads were predicted to have lower elasticity, due to the lower glutenin levels in the grain, both spelt varieties scored highly for crumb elasticity. The authors suggest this could be due to the “pregelatinisation” included in the baking protocol, which was included to promote gluten formation in the spelt breads, and was applied to all the bread types.