Search

This study assessed the effects of fermentation time (2, 3 and 4 days) and germination time (2, 3 and 4 days) on total phenolics, tannin, anthocyanin, carotenoids and flavonoids contents of lesser legumes: cowpea (Vigna unguiculata L.), bambaranut (Vigna subterranean L.), red bean (Phaseolus vulgaris), pigeonpea (Cajanus cajan), African breadfruit (Treculia africana) seeds, African yam bean (Sphenostylis stenocarpa) seed, African oil bean (Pentaclethra mycrophylla Benth.) seed and groundnut (Arachis hypogea L.). The antioxidant and reducing powers of a three day germinated samples were also evaluated. The result revealed that fermentation reduced the total phenolics, tannin, anthocyanin, carotenoid and flavonoid contents of the samples with increasing fermentation time; however, red bean showed minimal increase with increasing fermentation time. There was significant (p

The traditional practice of using sharp sand grains as abrasives to de-slime African breadfruit (Treculia africana) seeds leaves their kernels with traces of these contaminants. Some physical dimensions of the seed, its kernel and hull were determined using two major varieties: var. africana and var. inversa. The fruit head of var. africana was significantly (P ≤ 0.05) heavier and bulkier but contained less number of edible seeds in the pulp than var. inversa. It showed a fractional porosity of 0.309 compared to significantly (P ≤ 0.05) higher porosity (0.697) shown in var. inversa. The seed and kernel of var. africana were significantly (P ≤ 0.05) shorter, thicker and wider by 6.54 and 9.42; 2.00 and 2.04; and 10.38 and 16.55%, respectively, than var. inversa. Seed, kernel and hull densities of var. africana were 1.076, 0.984 and 0.072 (g/cm3) while those of var. inversa were 0.883, 0.834 and 0.032 (g/cm3), respectively. The hull contributed 0.19–8.12% to the difference between the seed and kernel shape in var. africana and 2.09–12.26% in var. inversa. The aspect ratio of var. africana seed (59–60) showed that it will behave more closely like a sphere on oscillating surface than var. inversa (44–59). PRACTICAL APPLICATIONS Three varieties of African breadfruit with characteristic physical dimensions relevant for seed type selection and kernel cleaning are known. Unfortunately, they are sold as mixed varieties, with the first two the most widely cultivated and consumed. Apart from contaminants that incidentally mix with the seeds during their extraction in the field, the deliberate use of sharp sand as abrasives to enhance de-sliming leaves the seeds with such contaminants. It is expected that the information obtained from this research might be useful in designing and fabricating mechanical cleaners for the kernel and other crops with similar physical dimensions with the attendant benefits of reducing the dangers and risks of exposing the teeth of the cleaners to stone damage. Seed type selection will be of interest to both breeders and consumers by eliminating nonuniformity in doneness during cooking due to varietal differences in mixed batches.

Five levels of African breadfruit (Treculia africana), corn and soybean mixtures (fc) in ratios of 40:5:55, 55:5:40, 70:5:25, 85:5:10 and 100:0:0, respectively, were hydrated to 15, 18, 21, 24 and 27% (fm) and extruded at 100, 120, 140, 160 and 180 rpm (ss) in a Brabender single-screw extruder. The objective was to study effects of process variable conditions on mineral and chemical composition of the mixtures. Models developed by response surface analysis were high (R2 = 0.7646–0.9732) for Na, Ca, Mg, protein, fat, fiber and carbohydrate, and showed no significant (P > 0.05) lack of fit. All process variables had significant (P ≤ 0.05) linear effects on Mg, protein and carbohydrate, quadratic effects on fat, energy and Mg and cross-product effects on Ca, Mg, protein and carbohydrate, when fc interacted with either fm or ss. Optimum process variable conditions that gave the best mineral and chemical composition were obtained at 40:5:55(fc), 18% (fm) and 140 rpm (ss). PRACTICAL APPLICATIONS The potentials of African breadfruit as a nutrient resource and its position in the food cycle of the people in the subtropical African countries makes its blending with other local ingredients one important way of expanding the scope of its utilization. African breadfruit seeds provide a delicacy and a specialized meal when consumed alone or with shelled milk-corn. The versatility and acceptance of extrusion as a processing technology and its benefits over conventional methods and worldwide adaptability to a variety of crops, makes its application in this research appropriate. Optimization of process variable conditions affecting mineral and chemical composition of extruded and unextruded mixtures of African breadfruit, corn and soybean, using response surface analysis, was the thrust of the study. It is expected to produce an optimum process combination that could give the best mineral and chemical composition for a possible scale-up operation in African breadfruit seed processing enterprises.

BACKGROUND: African breadfruit, from which diverse food forms are produced, is popular in most West African tropical regions. The present study is part of a larger research project aimed at developing appealing, processed, nutritious products from blends of breadfruit, corn and defatted soybean by utilising extrusion cooking using response surface analysis. The study describes the ability or otherwise of raw and extruded African breadfruit-based diets, similar to weaning diets simulated with rats, to support growth of children and infants. RESULTS: Maximum protein efficiency and net protein ratios of 2.22 and 3.69, respectively, were obtained with rats fed diets made from 40 g 100 g−1 African breadfruit + 5 g 100 g−1 corn + 55 g 100 g−1 soybean extrudates at 18 mL 100 mL−1 feed moisture and 140 rpm screw speed. It compared favourably with a casein standard and was 54–69% and 42–55% higher than those fed raw diets. CONCLUSION: Extrusion cooking significantly improved the nutritional quality of African breadfruit–corn–defatted soybean as reflected in their protein efficiency and net protein values. The superiority in protein quality of diet 1 (containing 40 g 100 g−1 breadfruit, 5 g 100 g−1 corn and 55 g 100 g−1 defatted soybean) over the other experimental diets has serious nutritional implication in dietary diversification to address protein-energy malnutrition prevalent in Nigeria and other West African countries especially where African breadfruit is known to be highly cultivated as a food resource. Copyright © 2007 Society of Chemical Industry

Full fat African breadfruit, corn and defatted soy blends with moisture content range of 6.20-7.50% (wet basis) were extruded in a single-screw Brabender laboratory extruder (DCE 330, Brabender Instruments Inc., South Hackensack, NJ) at varying independent process variables of feed composition (fc), feed moisture (fm) and screw speed. A central composite design was employed to study the effects of these variables and extrusion cooking on several quality characteristics of the center point blend, and energy input as torque and specific mechanical energy (SME). SME is relevant in that the more the energy applied, the greater the degradation of starch while torque is directly correlated with power usage. Extrusion cooking significantly (P ≤ 0.05) affected bulk density, water absorption, water solubility and nitrogen solubility indices. Torque and SME ranged from 4.00 to 8.50 N.m and 216 to 376 kJ/kg, respectively. Regression analysis of data generated of experimental data showed that fc had significant (P ≤ 0.05) quadratic effect on both energy measurements. Screw speed and fm showed significant (P ≤ 0.05) linear effects on SME while screw speed alone showed significant (P ≤ 0.05) linear effect on torque. At 160-rpm screw speed and 85% fc, the torque value was maximum (8.50 N-m). Maximum SME value of 376.72 kJ/kg was obtained at 85% fc, 24% fm and 120-rpm screw speed. Economically, therefore, extruded products made from blends of breadfruit, corn and soy flours will require lower extruder power usage given the fat and fm levels. Findings of this research might be useful to processors for better process control and optimal energy utilization when extruding these or related blends in a single-screw extruder.