Abstract
Wheat germ shows the highest nutritional value of the kernel. It is highly susceptible to rancidity due to high content of unsaturated fat and presence of oxidative and hydrolytic enzymes. In order to improve its shelf life, it is necessary to inactivate these enzymes by a thermal process. In this work the functional properties and some characteristics of the protein fraction of treated wheat germ were evaluated. Sequential extraction of proteins showed loss of protein solubility and formation of aggregates after heating. DSC thermograms showed that wheat germ treated for 20 min at 175 °C reached a protein denaturation degree of ~ 77%. The stabilization process of wheat germ affected significantly some functional properties, such as foaming stability and protein solubility at pH 2 and pH 8. Nevertheless, heating did not affect the water holding, oil holding and foaming capacity of protein isolates.
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The authors greatly acknowledge Consejo Nacional de Investigación Científicas y Técnicas (CONICET), Universidad Nacional de Córdoba-Argentina (UNC) and Agencia Nacional de Promoción Científica y Tecnológica for financial support.
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Meriles, S.P., Steffolani, M.E., León, A.E. et al. Physico-chemical characterization of protein fraction from stabilized wheat germ. Food Sci Biotechnol 28, 1327–1335 (2019). https://doi.org/10.1007/s10068-019-00594-9
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DOI: https://doi.org/10.1007/s10068-019-00594-9