Please cite this article as: Sritongtae, B., Sangsukiam, T., Morgan, M.R.A., Duangmal, K., Effect of acid pretreatment and the germination period on the composition and antioxidant activity of rice bean (Vigna umbellata), Food Chemistry (2017), doi: http://dx.doi.org/10.1016/j.foodchem. 2017.01.103 This is a PDF file of an unedited manuscript that has been accepted for publication. As a service to our customers we are providing this early version of the manuscript. The manuscript will undergo copyediting, typesetting, and review of the resulting proof before it is published in its final form. Please note that during the production process errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.
AbstractThis research evaluated effect of germination period and acid pretreatment on chemical composition and antioxidant activity of rice bean sprouts. Moisture, total phenolics, reducing sugar and B vitamins (thiamine, riboflavin, and niacin) content of steamed sprouts increased with increasing germination time (p≤0.05). Pretreatment with 1% (w/v) citric acid for 6 hours significantly increased the total phenolic content. The 18-hour-germinated rice beans showed the highest crude protein content, as determined using the Kjeldahl method. During germination, acid pretreatment led to a significant decrease in the intensity of the 76-kDa band. Germination caused a significant increase in radical scavenging activity and ferric reducing antioxidant power, especially in sprouts from citric acid-treated seeds. The antioxidant activities of the ethanolic extracts from both pretreated beans and the control were 1.3-1.6 times higher than those obtained from the water extracts. Major phenolics found in both 0-hour and 18-hour-germinated rice beans were catechin and rutin.