The use of kidney bean flour with intact cell walls reduces the formation of acrylamide in biscuits

Abstract

Acrylamide (AA) is formed by Maillard Reaction (MR), during high-temperature and low moisture processes in several food categories, including bakery products. AA is classified as a toxic and carcinogenic compound and therefore, mitigation strategies are necessary to control its concentration in foods. Selecting ingredients with a reduced amount of asparagine, the main AA precursor, is the most effective method of reducing the AA formation in bakery products.In the present study, the hypothesis that cotyledon cell walls integrity could prevent the formation of AA by modulating the dehydration rate and reducing the availability of asparagine during the MR development during baking was investigated. Legumes have strong cotyledon cell walls that can be preserved during flour production: in this study two kidney bean flours with intact and broken cell walls were used. The integrity of the cotyledon cell walls was assessed by scanning electron microscopy while AA, its precursors, moisture and water activity were measured in bean flours, raw doughs and baked biscuits. The biscuits were also characterised for the main baking parameters such as weight loss, pH, colour and texture.The results showed that biscuits formulated with bean flour with intact cell walls had a 15% less amount of AA than those made with the bean with damaged cell walls at the end of the cooking time. Furthermore, the use of the two different bean flours led to different quality characteristics of the biscuits in terms of hue angle and browning index, as colour parameters, and hardness, which is related to the texture properties. These differences were attributed to the different development of the MR and in the structure of the biscuit during baking. The use of intact plant tissue legume flours in alterative biscuits formulations is a feasible and low-cost approach that can contribute to the AA mitigation strategy.