Nutrient and antinutrient profiles of raw and fermented cocoa beans

Freshly harvested cocoa bean was subjected to natural fermentation for 3, 6, 9 or 12 days. The proximate, mineral, hydrocyanate (HCN), oxalate and theobromine levels in the products were determined and compared with those of raw (unfermented) cocoa. The latter sample had the following composition: protein (N×6.25), 17.5; lipid, 62.9; ash, 4.4; fibre, 5.9; and nitrogen-free extract (NFE), 9.3% dry matter. The effect of fermentation was variable, depending on duration and the nutrient under consideration. At day 3, protein content (17.6) was not different, but at day 6 (19.8) was higher (p<0.01), while days 9 and 12 (14.6 and 15.2, respectively) were lower (p<0.01) in comparison with the raw value. Inorganic P steadily decreased from 201.0 (raw) to 102.0 mg/100 g dry matter (day 12) but only the days 9 and 12 values were significantly different (p<0.05), whereas Ca increased from 29.2 (raw) up to 60.4 mg/100 g dry matter (day 3). The antinutrients, HCN, oxalate, and theobromine decreased with increasing duration of fermentation. The decreases for days 6, 9 and 12 were significant (p<0.05). The results are discussed with regard to optimization of the duration of cocoa fermentation for improved nutrient profile.     

Effect of domestic processing on the cooking time,nutrients, antinutrients andin vitro Protein digestibility of the African yambean (Sphenostylis stenocarpa)

The effects of processing (soaking, dehulling, fermentation and heat treatment) on the cooking time, protien, mineral, tannin, phytate and in vitro protein digestibility (IVPD) of the african yambean (AYB) were examined. The cooking time ranged from 90–155 minutes. Soaking reduced cooking time by about 50 percent. Soaking for 12 hours was the most appropriate to reduce cooking time, tannin and phytate levels. It improved in vitro protein digestibility (IVPD). Prolonged soaking (24 hours) decreased calcium (Ca) and iron (Fe) values by 19 percent and 35 percent, respectively. Dehulling showed that Ca, Fe, magnesium (Mg) and zinc (Zn) were concentrated in the seed coat of the AYB. The seeds soaked and dehulled retained Mg and Zn. Dehulling reduced tannin but had no significant effect on phytate and the IVPD of the AYB except for seeds soaked for 12 hours before dehulling. Soaking for 24 hours before dehulling significantly increased crude protein content by 16 percent (p<0.05). Blanching and roasting increased the IVPD by 8–11 percent. Fermentation had no effect on the crude protein, Ca, Fe, Mg and Zn but significantly reduced phytate content of the AYB. Fermentation had no advantage over heat treatment with respect to improving the in vitro protein digestibility of the AYB.     

Nutrient and antinutrient composition of Amaranthus muricatus

The chemical and nutritional composition of theaerial parts of Amaranthus muricatus wasassessed. This is a wild plant growing well in aridand poor soil, which are not suitable for cereals. Thematerial under study was boiled, dried and ground andthen evaluated for chemical, nutritional andantinutritional properties. Protein concentration ofthe amaranth flour was 15.74 g/100 g and total dietaryfiber content was high (53.81 g/100 g), with 79%coming from insoluble dietary fiber. The calciumcontent was 1533 mg/100 g and the Ca/P ratio (5.94)was markedly higher than the value suggested in the1989 Recommended Dietary Allowances. Fifty-ninepercent of the fatty acids present were unsaturatedwith linoleic acid accounting for 40% of the totalfatty acid content. Nitrate, hemagglutinin, trypsininhibitor and saponin contents were within thenon-critical values. Net protein utilization (NPU),true digestibility (tD) and biological value (BV)measurements indicated a nitrogen gain of 74% that ofcasein. The results of this study indicate a nutritivepotential for the A. muricatus leaves, therefore,domestication of this plant is suggested along withassessment of its chemical and nutritionalproperties.     

Effect of processing method on the quality of cowpea (Vigna unguiculata) flour for akara preparation

An indigenous food mixture containing rice flour, milk coprecipitate, sprouted green gram paste and tomato pulp (2: 1: 1: 1 w/w) was developed and called a RCGT food mixture. It was autoclaved (1.5 kg/cm², 15min, 121 °C), cooled and fermented with 2% liquid culture (containing 10⁶ cells/ml broth). Two types of fermentations were carried out i.e. one step single culture fermentation [L. casei or L. plantarum (37 °C, 24 hr.)] and sequential culture fermentation [S. boulardii (25 °C, 24 hr.) +L. casei (37 °C, 24 hr.)]; [S. boulardii (25 °C, 24 hr.) + L. plantarum (37 °C, 24 hr.)]. All fermentations drastically reduced the contents of phytic acid, polyphenols and trypsin inhibitor activity while significantly improving the in vitro digestibilities of starch and protein. Sequential culture fermentations brought about further changes compared to one step single culture fermentation.     

Nutrient and antinutrient composition of three varieties ofPiper species

The proximate composition of three varieties ofPiper guineense (Odusa — Ibibio/Efik) viz. Uyat Odusa (cultivated and peppery), Eting-keni Ikot (wild forest variety) and Eting-keni mben inyang (wild, riverine variety), were determined using available standard methods. Also determined were mineral, antinutrient and ascorbate levels. The cultivated pepperic variety had the highest content of crude protein and moisture (18.9% and 97% respectively) while the wild, riverine variety had the highest content of ether extract, carbohydrate and calories (7.79%, 63.38% and 398 cals respectively). The cultivated variety had appreciable amounts of phosphorus (1.12 mg/100 g), potassium (1.2 mg/100 g), sodium (0.24 mg/100 g), zinc (0.18 mg/100 g), and copper (0.18 mg/100 g) while the forest variety contained more of calcium (12.38 mg/100 g), magnesium (1.21 mg/100 g) and iron (0.85 mg/100 g). The wild riverine variety appeared to have the least mineral content but had the highest ascorbate level of 173.4 mg/100 g. Of four antinutrients assayed, the cultivated pepperic one had the least quantities while the forest variety was highest in hydrocyanic acid (85.8 mg/100 g) and glucosinolates (0.20 mg/100 g). The wild riverine variety had the highest level of total oxalate (165.0 mg/100 g). These quantities are however far below documented toxic levels.     

Content of antinutrients and in vitro protein digestibility of the African yambean,pigeon and cowpea

The protein, trypsin inhibitor (TI), tannin, phytate, phytic acid phosphorus and in vitro protein digestibility (IVPD) of cultivars of the African yambean (Sphenostylis stenocarpa) — AYB, pigeon pea (Cajanus cajan) — PP and cowpea (Vigna unguiculata) — CP were determined. The protein content of CP (24–28.0%) was higher than those of PP (21–22.5%) and AYB (21–22.5%). The cream and speckled AYB contained more TI (30.9 and 25.3 mg/g) than PP (7.5–14.1 mg/g) and CP (9.8–20.5 mg/g). Apart from the white CP cultivar, they contained more tannin (1.24–1.42 mg/g) than PP (0.14–0.97 mg/g) and AYB (0.71–1.17 mg/g). Phytate was lowest in the AYB (6.30–7.49 mg/g) than PP (8.31–11.31 mg/g) and CP (8.40–9.92 mg/g). Phytic acid contributed 67–74% of the phosphorous in the AYB, 66–75% in PP and 54–59% in CP. The IVPD of the AYB (73.3±0.7%) was significantly lower (p<0.05) than those of PP (76.34±0.2%) and CP (77.8±0.4%). There was a significant negative correlation between TI and IVPD (r=–0.63,p<0.05). There was no significant correlation between IVPD and phytate and tannin contents. There was a positive correlation between protein content and IVPD (r=0.69**) for the legumes under study. These legumes may pose no serious problems to populations consuming them especially when heat treatment is applied before consumption.     

中国菜籽饼的营养成分和抗营养因子

在全国２０个主要菜籽产区采取１５２个菜籽饼和４５个菜籽粕，对它们的各种营养成分和菜籽饼粕中的各种抗营养因子，硫葡萄糖苷含量及其分解产物恶唑烷硫酮和异硫氰酸酯含量均进行了分析测定。结果表明，我国菜籽中有毒物质含量较高，在用作饲料时必须合理安全使用，或在使用前进行适当的脱毒处理。     

Effects of dehydrated methanol extracts of moringa (Moringa oleifera Lam.) leaves and three of its fractions on growth performance and feed nutrient assimilation in Nile tilapia (Oreochromis niloticus (L.))

A 10-week feeding trial was conducted in a recirculation system at (27 ± 0.5 °C) to determine the effect of a methanol extract of moringa leaf meal and its different fractions. Nine isonitrogenous and isoenergetic diets containing 35% crude protein and 20 MJ kg^− 1 gross energy were used. All the experimental diets contained the same amount of fish meal. The inclusion of moringa methanol extract or of moringa extract fractions occurred by replacing the wheat meal. These diets were then denoted as diets 1 (control without any moringa product), 2, 3 (containing respectively 10.6 and 17.7% of moringa leaf meal methanol extract), 4, 5 (containing respectively 9.3 and 15.4% of a tannin-reduced fraction), 6, 7 (containing respectively 2.6 and 4.3% of a saponin-enriched fraction), 8 and 9 (containing respectively 7 and 11.6% of a tannin- and saponin-reduced fraction). Thirty six fish (four fish per treatment), with mean initial body mass of 4.9-5.2 g, were kept individually. They were fed the experimental diets at the rate of 15 g feed per kg metabolic body weight (kg^0.8) per day. Up to the 5th experimental week, no difference in growth performance was observed between all the groups. At the end of the experiment, a significant (P < 0.05) reduction of the growth performance of all the fish fed diets containing moringa 80% methanol extract or the extract fractions was generally observed when they were compared to the fish fed with the control diet. The whole body moisture, ash and crude protein of the fish fed diets containing moringa crude extract or extract fractions were not significantly different to those of the control group. Body lipid was significantly reduced for the fish fed the diets 2, 4, 5 and 9 when compared to control. Muscle and plasma cholesterol levels were generally reduced for the fish fed diets containing moringa extract and extract fractions (except for the group 5 which showed higher muscle cholesterol than that of the control). The fish in the groups 2 and 5 had significantly lower hepatosomatic indices when compared to control. On the other hand, the intestinalsomatic indices (ISI) of the groups 2, 3, 4, 5, 6 and 7 were generally higher than the control group and the groups 8 and 9 had lower ISI than the control group. The relatively high total phenolics and saponins in diets 2 to 9 may have contributed to the poorer growth performance in these groups.     

Diplazium sammatii: Athyraceae (`Nyama Idim'): Age-related nutritional and antinutritional analysis

Tender and mature leaflets and leaves of Diplazium sammatii (`Nyama idim'), were separately investigated for their nutritional and antinutritional properties. Results showed little difference in proximate nutritional contents between tender and mature leaves, except for crude fat, which was present in levels 1.5 times higher in younger than in older leaves. Crude fiber levels were low. Zinc (Zn) and copper (Cu) were higher in younger leaves (6.8 and 3.5 mg/100 g dry matter, respectively, compared to 4.5 and 2.5 mg/100 g dry matter, respectively in older leaves). Older leaves contained higher levels of iron (Fe): 6.7 mg/100 g dry matter, in comparison to 4.3mg/100 g dry matter, in young leaves. Oxalate levels were slightly higher in younger than older leaves. However, the reverse was true for tannin content. Both antinutritional compounds were present in levels which shouldbe safe.     

Levels of antinutritional factors in pearl millet as affected by processing treatments and various types of fermentation

Pearl millet (Pennisetum typhoideum) was fermented with Lactobacilli or yeasts alone and in combination, and with natural microflora after various processing treatments, as grinding, soaking, debranning, dry heat treatment, autoclaving and germination. Fermentation was carried out at 30°C for 48 hours withLactobacillus plantarum (LP) andRhodotorula (R) isolated from naturally fermented pearl millet andLactobacillus acidophilus (LA),Candida utilis (CU) and natural microflora (NF). Germination and autoclaving, and debranning and autoclaving were the most effective processing treatments to reduce the phytic acid, amylase inhibitors and polyphenols. There was a further reduction in these antinutrients due to fermentation. Phytic acid and amylase inhibitors were completely eliminated after fermentation in some of the samples especially in soaked, debranned and germinated ones. Polyphenols were altered non-significantly in general but fermentation with Lp+R and NF caused a significant increased in polyphenols.