The saponins content of some Nigerian oil seeds

Three oil bearing seeds grown in Nigeria were found to contain saponins. The oil seeds, African oil bean seed (Pentaclethra macrophylla) rubber seed (Havea brasilienses), andMucuna uriens were defatted and saponin fractions extracted with 20% aqueous ethanol. Saponins obtained after extraction were 2.1% for African oil bean seed, 1.8% for rubber seed, and 2.1% forMucuna. These figures were similar to that of defatted soyabean with 2.4%. Results are discussed in relation to the possible beneficial or detrimental effects of saponins to man or animals that may consume these oil seeds.     

Effect of traditional processing of cassava on the cyanide content of gari and cassava flour

Detoxification of cassava cultivars (30572 TMS and 30555 TMS) during their traditional methods of processing to produce gari and cassava flour has been investigated. The HCN quantitative determination was done using the enzymatic assay. Fermentation of cassava pulp for 96 hours during cassava processing for gari reduced the HCN by 22 ppm (52.4 percent) and 20 ppm (57.3 percent) for 30572 TMS and 30555 TMS respectively. There was no significant difference (P>0.05) in the HCN content of the two cultivars. Soaking of the sliced cassava tissue for 24 hours in cassava flour production prior to sundrying resulted in 16 ppm (38.1 percent) and 15 ppm (38.4 percent) HCN reduction for 30572 TMS and 30555 TMS respectively. HCN loss during sundrying was 6 ppm (14.3 percent) and 5 ppm (12.8 percent) for the two cultivars. There was significantly (P<0.05) higher HCN loss in processing of gari than cassava flour. The residual cyanide in gari was 12 ppm for 30572 TMS and 10 ppm for 30555 TMS and that in the flour was 20 ppm for 30572 and 19 ppm for 30555 TMS.     

Changes in nitrogenous and other chemical constituents,protein fractions and in vitro protein digestibility of germinating fluted pumpkin ( Telfairia occidentalis Hook) seed

The effect of 7 days of germination on levels of nitrogenous and other nutrition related parameters, protein fractions and in vitro protein digestibility of fluted pumpkin (Telfairia occidentalis) seed was studied. The non-protein nitrogen gradually increased and the protein nitrogen content decreased during germination. Albumin and globulin fractions were found to be the major seed proteins of fluted pumpkin seeds, constituting about 58.6% of the total protein of the ungerminated (raw) seeds. The protein fractions, albumin and glutelin, were observed to increase by 61.5% and 57.0%, respectively, while a 54.6% decrease was noted in the prolamine fraction. The globulin fraction increased at the beginning of germination but decreased at the end. Germination significantly (p 0.05) increased the crude protein, nitrogen solubility and in vitro protein digestibility but decreased the fat, phytic acid and polyphenol contents of the seeds.     

Ascorbic acid content of some Nigerian local fruits and vegetables

Plant Foods for Human Nutrition - Ascorbic acid contents of some common local fruits and vegetables was determined. The ascorbic acid contents of the fruits ranged from 21.8 to 98.0 mg per 100 g...     

Quality attributes and storage stability of locally and mechanically extracted crude palm oils in selected communities in Rivers and Bayelsa States,Nigeria

The effect of different extraction methods on the qualityof crude palm oil processed using traditional (local) and mechanical methods in selected areas of Rivers and BayelsaStates and their storage stability were investigated.Certain quality determining parameters such as free fatty acids (FFA), peroxide value (PV), saponification value (SV),moisture, impurities and volatile matter (MIV) content weredetermined prior to and after storage for three months. The free fatty acids (FFA) ranged from 7 to 19 percent, peroxidevalue (PV) ranged from 3 mEq/kg to 6 mEq/kg and moisture, impurity and volatile matter (MIV) ranged from 0.21 to 0.64 percent for locally extracted crude palm oil samples and mechanically extracted crude palm oil samples. There was no significant difference (p > 0.05) in the FFA of samples A and E before and after storage for 3 months. Also two of thelocally extracted crude samples (A and E) stored better whileone of the samples (D) showed a high level of deteriorationas shown in its high levels of FFA, PV and IV values. SamplesA and E resulted in a better quality of oil in terms of FFA (av. 7.25%) and PV (av. 4.5 meg/kg) when compared to the mechanically extracted one (sample C) with FFA (10.0%) and PV (5.78 mEq/kg). However, all the locally and mechanically extracted crude palm oil samples could not meet the industrial and international standard quality for crude palm with FFA (2–5%) and PV (2–3.5 mEq/kg). Among the three different storage containers used under different storage conditions, plastic containers (PC) resulted in a better storage stability of the crude palm oils in terms of FFA, SV, and IV than transparent bottles stored on shelves (TBS) and amber-coloredbottles stored on the bare floor (BPF).     

Effects of cooking,germination and fermentation on the chemical composition of Nigerian Cowpea (Vigna unguiculata)

The effects of cooking, germination, and fermentation on the chemical composition of cowpea were studied. There were noticeable trends in the protein, carbohydrate and crude fiber as a result of the different treatments. Both the germinated and fermented samples contained more ether extractable lipids than the raw and cooked samples. Untreated raw cowpea contained 5.9 mg/g phytic acid, 1.66 mg/g phytate phosphorus, 3.3 mg/g total phosphorus, 56.8 mg/g total sugar, and no reducing sugar. Cooking the dry beans at 100°C for 1 1/2 hours had little effect on the phytic acid and phytate phosphorus. There were, however, significant decreases in total phosphorus and sugars of the cooked beans. After germination for 24 hours, 48 hours and 72 hours respectively, there was a significant decrease in phytic acid and total sugar and increase in total phosphorus and reducing sugar. Similar results were also obtained when the dry beans was fermented for 24 hours, 48 hours and 72 hours respectively.     

Effects of processing on protein nutritive quality of coconut Cocos nucifera products

Pared, comminuted and blanched coconut meat was freeze-dried at25 ^°C for 24 hours and pulverized. Whole coconut meal wassolvent extracted with n-hexane to yield a defatted meal while full-fatcoconut protein concentrate (FFC-PC) containing 27.60% protein wasprepared by alkali extraction of undefatted meal followed by isoelectricprecipitation. Defatted coconut meal had a significantly (p 0.05)lower crude fat but higher protein content than whole coconut meal.Similarly, FFC-PC had a significantly (p 0.05) higher proteinbut lower carbohydrate content than whole coconut meal and defattedcoconut meal. Whole coconut meal, defatted coconut meal and FFC-PChad PERs of 1.98, 2.18 and 2.48 respectively, with NPRs of 2.86, 3.28and 3.92, respectively. Protein digestibility values of 88.75%, 89.30%and 94.02% were obtained for whole coconut meal, defatted coconutmeal and full-fat coconut protein concentrate, respectively. Growthresponse of animals showed that FPC-PC was superior to all other testdiets.     

Development of an owoh-type product from African yam beans (Sphenostylis stenocarpa) (Hoechst (ex. A. Rich.) Harms.) seeds by solid substrate fermentation

African yam beans were fermented to obtain anowoh-type product. Microorganisms associatedwith the fermentation were Bacilluslicheniformis, B. pumilus, B. subtilis and Staphylococcus sp. Total microbial counts increasedfrom 1.53 × 10⁵cfu/g to 1.51 × 10⁹cfu/g under aerobic conditions, and from 8.0 × 10³cfu/g to 1.35 × 10⁷ cfu/g under conditions ofreduced oxygen tension. The pH of the substrateincreased throughout the fermentation, from 6.8 to7.5. A comparison of unfermented seeds with thefermented product showed that there were decreases inthe levels of total nitrogen, crude protein, crudefiber and lipids, and that there were increases in thelevels of carbohydrate and total organic matter.Enzyme activities during fermentation revealed thatamylase production was erratic showing a slightincrease during the first 24 h followed by a steeprise in activity in the next 24 h. By contrast, lipaseactivity increased rapidly throughout the first 72 hwhile proteinase activity followed a type of sigmoidcurve with a steady increase in activity within thefirst 48 h and a relatively high activity until the96^th h before plunging downwards.     

Chemical composition of indigenous wild herbs,spices, fruits,nuts and leafy vegetables used as food

Thirty wild fruits, nuts, herbs, spices and leafy vegetables were characterized and their chemical composition determined. Some of them were not only used for food, but for medicine in minor aliments by the natives. Results of the proximate analysis showed that on dry weight basis, the crude protein content ranged from 4.6 to 22.1 percent for spices and herbs, 3.2 to 43.1 percent for fruits and nuts, and 15.9 to 35.7 percent for leafy vegetables. The fat (ether extract) ranged from 7.5 to 36.0 percent for spices and herbs, 1.8 to 72.6 percent for fruits and nuts and 10.6 to 22.6 percent for leafy vegetables. Total carbohydrate content ranged from 34.6 to 71.9 percent for spices and herbs, 11.3 to 76.1 percent for fruits and nuts, and 24.6 to 51.4 percent for leafy vegetables. The wild fruits, nuts and leafy vegetables are high in ascorbic acid (Vitamin C.) Ascorbic acid content ranged from 18 mg/100 g dry sample to 113 mg/100 g sample for fruits and nuts, and 23 mg/100 g to 232 mg/100 g sample for leafy vegetables. The levels for peroxide value and free fatty acids (as percent oleic acid) of the spices are generally low indicating good storage stability of these plant materials. The flavour imparting essential oils (as percent oleoresin) content of the spices/herbs were fairly high and ranged from 0.1 to 5.2 percent.     

Physicochemical properties and garification (gari yield) of selected cassava cultivars in Rivers State,Nigeria

Gari was processed from six different cassava cultivars TMS 3575, TMS 3044, hormone treated variety (HTV), TMS 30555, TMS 40944 and TMS 30572. Chemical analyses of the gari samples showed pH values of: 4.0, 4.0, 3.9, 3.6, 3.4, 3.6 and total titratable acidity of 0.99, 0.99, 0.98, 0.85, 0.96, 0.85 (% lactic acid) for TMS 3575, 3044, HTV, 30555, 30572, and 40944 respectively. Physical characteristics of the samples showed the swelling index of 264.5%, 223.5%, 364.0%, 321.3%, 241.3% and 232.7%, water absorption capacity of 1.0 ml g-1, 0.8, 1.5, 1.9, 1.7, 1.9 ml g-1 sample, relative bulk density of 0.29, 0.30, 0.15, 0.17, 0.15 (g cm-3) and gari yield of 34%, 21%, 33%, 24%, and 23%, for cultivars, TMS 3575 (2), 3044, HTV, 30555, 30572, 40944 respectively. Sensory evaluation showed a significant difference (p < 0.05) in quality and overall acceptability among the samples while Tukey test showed a difference ( p< 0.05) between HTV and between 3575 and 3044. The cassava pulp from the cultivars and their corresponding gari had HCN content (mg/100 g) ranging from 7.9 to 9.3 for pulp and 1.1 to 1.5 for gari, respectively. The 72 hours fermentation period reduced the HCN in all cultivars by 85%, which is considered to be a safe level for human consumption.