Souad Bensaada
Université de Bordeaux, France
Title: An improved food process reducing Isoflavones in soy-based foodstuffs to decrease their impact on health
Biography
Biography: Souad Bensaada
Abstract
Statement of the Problem: Isoflavones are natural active compounds occurring in soy and other legumes as part of their anti-predators’ arsenal. They have shown estrogenic, anti-estrogenic, anti-androgenic and thyroid effects. An intake over 40 mg/day induces an impairment of menstrual cycles in women, proliferating effects on women’s breast cancer, goiters in children fed soy infant formulas and a reduction of men’s sperm quality. Therefore, according to current knowledge, the risk/benefit balance of their consumption tilts towards a reduced exposure. Meanwhile, the daily consumption of isoflavones is increasing in Western countries, either directly through the consumption of soy-based foodstuff or indirectly through soy proteins hidden in processed dished. The purpose of this study is thus to achieve non-worrying isoflavones levels in soy-matter according to the reprotoxic LOAEL1 for genistein which was published in 2008 by the US-NTP2. Based on previous measurements, new steps were included by soy-food manufacturers which can remove up to 90% of the isoflavones of soy proteins-based dishes. Such treatments lead to adequate isoflavone intake for adults but not for children. To reduce isoflavones further, some food-processing steps mimicking those found in traditional Asian recipes were added to the production process of soy-proteins. Methodology & results: New food-processing steps were performed at both laboratory and pilot scales, on soy proteins. Isoflavone assays were performed using ELISA techniques. The optimization of the parameters resulted in an additional isoflavone removal over 40% which gives an adequate intake for the whole population. Conclusion & Significance: This study showed that it is possible to significantly reduce isoflavones in soy-proteins without impacting their main properties: size, water, lipid or protein content. This, provides a safer raw material for the food industry using soy proteins. Pre-industrial scale-up should confirm the accuracy of the selected parameters.