RESUMO
The present study is aimed at producing Sorghum bicolor and Voandzeia subterranea complementary instant flour. The precooked sorghum and Bambara groundnut flours were mixed at different proportions (0 : 100, 25 : 75, 50 : 50, 75 : 25, and 100 : 0), hydrated with sterile distilled water (1 : 3, w:v), and fermented for 72 h/37°C using Lactobacillus plantarum A6 at 105 CFU/g. During the fermentation, samples were withdrawn for pH, titrable acidity, and microbial analyses. After fermentation, color, particle size, water absorption capacity (WAC), solubility index, least gelling concentration (LGC), and physicochemical and pasting properties were determined. The results showed that the fermentation significantly (p ≤ 0.05) decreased WAC, LGC, peak viscosity, final viscosity, breakdown, and pH, but increased the solubility index and titrable acidity of flours. The protein and carbohydrates contents as well as the color, particle size, and the setback after the cooking of the flour were not significantly affected by the fermentation. The flours ratio and fermentation also significantly decreased the total polyphenols, tannins, and phytate content of the samples. The fermented blended flour containing 25% precooked sorghum flour and 75% roasted Bambara flour (SVFP25) is a promising alternative as instant flour used for young children's nutrition.
RESUMO
Tropical roots and tubers generally contain mucilage. These mucilages exhibit unique rheological properties with considerable potential as a food thickener and stabilizer. A one-step extraction procedure was used to isolate starch free mucilage and associated proteins from a number of taro (Colocasia esculenta) varieties. The monosaccharide and amino acid composition, the structural and flow properties were investigated. The results showed that yield of mucilage fraction varied from 30 to 190 g.kg(-1). A negative correlation (r = -0.87; p < 0.05) was observed between the crude protein level and the yield. The monosaccharide profiles revealed that galactose, mannose and arabinose were the main monosaccharides in the hydrolysate of the mucilage. From the 17 amino acids analyzed, aspartic acid/asparagine (14.4-17.2%) and glutamic acid/glutamine (10.3-13.6%) were prominent in the mucilage as well as the flour. No significant differences were observed in the FT-IR spectra and in the viscosity behavior of the mucilage dispersions. The greatest difference in the mucilage is based on its monosaccharide profile while the protein composition, which reflects that of the flour, is relatively stable.
RESUMO
Investigations were conducted to determine the chemical composition, antifungal and antiradical activities of the essential oil extracted from the fresh leaves of Clausena anisata (Willd.) Hook. F. ex Benth (from Cameroon) against Aspergillus flavus, A. niger, A. parasiticus and Fusarium moniliforme. The essential oil obtained by hydrodistillation was analysed by GC and GC/MS. The disc diffusion method was used to evaluate the fungal growth inhibition at various concentrations of the oil while the antiradical activity of the essential oil was studied by the DPPH (diphenyl picryl hydrazyl) method. The main components obtained were E-ocimenone (15.1%), Z-ocimenone (11.5%), gamma-terpinene (11.4%) and germacrene D (10.9%). After 10 days of incubation on essential oil supplemented medium, the growth of A. flavus, A. niger, A. parasiticus and F. moniliforme were totally inhibited by 4, 5, 5 and 5 mg/mL of C. anisata essential oil, respectively. The antiradical activity of C. anisata essential oil (SC50 = 5.1 g/L) was less than that of butylated hydroxyl toluene (BHT), which was used as the reference compound (SC50 = 0.007 g/L). Results obtained in the present study indicate the possibility of exploiting C. anisata essential oil to fight strains of A. flavus, A. niger, A. parasiticus and F. moniliforme responsible for biodeterioration of stored food products.
