Nigerian Food Journal最新文献

Manipulation of fermentation variables during ugba production (fermented African oil bean (Pentaclethra macrophylla) seed), using traditional method was studied with the view to improving the fermentation process, quality of product and prediction of process. The variables studied were number of leaves used in wrapping, relative humidity (RH) and temperature. Effect of variables on pH and amino nitrogen was determined on 24 h basis for 96 h. Attempt on prediction and optimization of process using response surface method was made. Amino nitrogen increased with fermentation time and attained its peak at 72 h. The highest daily amino nitrogen value (3.4 mg N/g) was obtained from sample fermented at 65% RH, temperature 30 °C and 5 layers of leaves used for wrapping. pH increased into the alkaline range within the period, the highest value (8.2) being from sample fermented at 65% RH, 40 °C and 10 layers of leaves. Statistical analysis and response surface plots associated with analysis showed that the quadratic effect of variables was significant (p<0.05). Effects of number of leaves used in wrapping and relative humidity were significant and accounted for 95.31% of the amino nitrogen variation. Thus use of response surface method predicted the process and can be used to optimize the fermentation process. This ultimately will improve product quality.

The microbial quality of five different brands of noodles (designated as D, G, H, I and M) with their accompanying seasonings commonly marketed and consumed in Nigeria were investigated. The samples were serially diluted and using the pour plate technique least microbial load was obtained by heating samples at 100 °C for 10 min. Sample G had the highest bacterial count of 43.8×10⁵ cfu/ml for cold noodles, while sample M had the highest count of 32.0×10⁴ cfu/ml for hot noodles. For the seasonings, the total bacterial count varied with sample M having the highest bacterial count of 31.2×10⁵ cfu/ml and 40.0×10⁵ cfu/ml for hot and cold seasonings respectively while for the chilli, sample D had the highest bacterial count of 36.0×10⁵ cfu/ml for cold chilli and sample I had the lowest bacterial count of 28.8×10⁵ cfu/ml. The total fungal count of all samples was less than that of the bacterial counts. Microbial analysis showed the presence of Bacillus, Pseudomonas, Staphylococcus, Aeromonas and Streptococcus. Staphylococcus sp was the most frequently isolated while the five genera of fungi isolated were Aspergillus, Mucor, Penicillum, Rhodotorula and Candida. The implications of these findings on the health of the populace were discussed from the microbiological point of view.

This work was aimed at evaluating the functional properties of six varying percentage blends of locally abundant, under-utilized crops; malted acha (Digitaria exilis), aya (Cyperus esculentus) and ede (Colocasia esculenta) as a substitute for the traditional weaning food. The results of bulk density and starch digestibility showed a decrease with increasing percentage addition of malted acha with values from 5.889 ± 0.98 to 7.953 ± 0.103 and − 5.45 to − 13.6 respectively. While water absorption capacity, measure of dispersibility, wettability, swelling power, % solubility increased with increase in percentage addition of malted acha with values from 6.6 ± 0.712 to 8.1 ± 0.1, 2.12 to 37.225, 3.21 ± 0.04 to 3.6 ± 0.03 and 20.64 to 24.46 respectively. There was no significant difference between any of the formulae and the control. Results of pasting properties showed that the peak viscosity, break down, final viscosity and setback values ranges from − 0.42 ± 0.085 to − 3.67 ± 0.085, 5.63 ± 0.045 to 1.79 ± 0.04, − 3.88 ± 0.045 to − 1.475 ± 0.275 and 2.17 ± 0.045 to 2.93 ± 0.045 respectively. The formulae compared favourably with the control, a commercially sold weaning food.

Four cowpea varieties (Brown beans, Oloka beans, IAR48 and IT89KD-288) were toasted at 105 °C, and used to study the effect of dry heat treatment on the cooking time and nutrient composition of cowpea seeds and also its effect on the functional properties of resultant flour of the cowpea seed varieties. Toasting reduced the cooking time for brown and oloka cowpea varieties from 55.00–31.00 and 70.67–51.67 min, respectively. The cooking time for IAR48 and IT89KD-288 cowpea varieties increased from 104.67 to 106.00 and 88.00 to 88.67 min, respectively. The results indicate that the cooking time of cowpea seeds can be reduced significantly on toasting, while maintaining their potential as functional agents in the food industry for nutrition and utilisation. Correlation between the amount of water imbibed by cowpea seeds and their cooking time was -0.74, but was not significant at p ≤ 0.05, suggesting that there is no significant relationship between the amount of water imbibed by cowpea seeds and their cooking time.