title: Effect of Soaking and Roasting on the Physicochemical and Pasting Properties of Soybean Flour.
abstract: The effects of soaking and roasting on the physicochemical and pasting properties of soybean flour were evaluated. Soybean seeds were soaked overnight in tap water for 0-72 h, hand dehulled, dried, and part of the sample was roasted. Roasted and unroasted soy beans were milled into flour and analyzed. The results showed that the total carbohydrates (22.8-27.9 g/100 g), the ash content (3.5-3.6 g/100 g), and the total polyphenols (0.29-0.51 g/100g) did not significantly change during both the soaking and roasting processes. However, the total proteins (35.8-46.0 g/100 g) and lipid contents (21.4-29.5 g/100 g) were significantly (p < 0.05) affected only by soaking, with a decrease in total protein and an increase in lipid contents. Phytate content (0.22-0.26 g/100 g) decreased significantly (p < 0.05) only with roasting. The tannins (0.01-0.30 g/100 g) and soluble proteins (4.0-29.0 g/100 g) significantly (p < 0.05) diminished with both treatments. There was a significant increase in the least gelation concentration (20-30 g/100 mL), a decrease in the swelling power (1.3-2.0 mL/mL), and consequently, reduction in the viscosity (range peak viscosity 18-210 cP) of the flour slurry after soaking and roasting. All these qualities-needed for producing nutritious flour for infants-highlighted the efficiency of these endogenous technologies.
authors.affiliation: Department of Food Sciences and Quality Control, Institut Universitaire de Technologie (IUT), University of Ngaoundere, P.O. Box 455, Ngaoundere, Cameroon. aurelie_agume@yahoo.fr.
authors.forename: Aurelie Solange Ntso
authors.initials: AS
authors.lastname: Agume
authors.affiliation: Department of Biological Sciences, Faculty of Science, University of Ngaoundere, P.O. Box 454, Ngaoundere, Cameroon. njintang@yahoo.fr.
authors.forename: Nicolas Yanou
authors.initials: NY
authors.lastname: Njintang
authors.affiliation: Department of Food Sciences and Nutrition, ENSAI, University of Ngaoundere, P.O. Box 455, Ngaoundere, Cameroon. cmbofung@yahoo.com.
authors.forename: Carl Moses F
authors.initials: CM
authors.lastname: Mbofung
keywords: physicochemical properties; roasting; soaking; soybean flour; viscosity