Quality changes in cocoyam flours during storage
Abstract Cocoyam tubers were subjected to two processing methods (fermentation and parboiling) and milled into flour. The samples were stored at 25°C, 35°C, and 45°C and analyzed at 2 weeks interval for 8 weeks for their nutritional, functional, and pasting properties. Data obtained were subjected to multiple analysis of variance. Storage period and its interactive effect with the processing methods had significant (P < 0.05) effects on all the nutritional composition of the flour except for the fat content. Water absorption index, wettability, and bulk density ranged from 1.94–2.72%, 25.30–135.50 sec, and 0.48–0.71 g/cm3, respectively. The entire pasting properties were significantly affected by the storage period while the interaction between storage temperature, processing methods, and storage period affected all the pasting properties except the peak time, peak, and breakdown viscosity. This study showed that processing methods storage periods and storage temperatures produced cocoyam flour with different quality characteristics.
Effect of storage temperature and time on fiber content of fresh and ensiled alfalfa.
To determine effects of storage temperature and time on fiber content, fresh alfalfa (late vegetative) was hand-clipped from three locations (blocks) and stored fresh or ensiled at -20 degrees C or +60 degrees C for 0, 24, 48, 96, 168, or 336 h. The experimental design was a randomized complete block with a 2 x 2 factorial arrangement of treatments. Main effects were method of forage conservation (fresh or ensiled) and temperature of storage (-20 degrees C or + 60 degrees C). Length of storage (0, 24, 48, 96, 168, or 336 h) was in the subplot. Conservation method x storage temperature x time interactions were detected (P < .05) for NDF, IVDMD, ADIN, and N content of NDF. Large increases in alfalfa NDF were observed up to 168 h of storage at 60 degrees C, whereas when fresh alfalfa was stored at -20 degrees C, small increases were observed up to 48 h but a large increase was observed after 168 h. Ensiled alfalfa stored at -20 degrees C had no change in NDF content. Contributors to increased NDF seemed due to changes in protein solubility and glycosylamine formation when fresh forage was stored at 60 degrees C, and changes in protein solubility, glycosylamine formation, and Maillard product formation when ensiled forage was stored at 60 degrees C. At -20 degrees C, formation of adducts with arabinose and glucose from nonstructural carbohydrates as well as polymerization and fragmentation of cell wall monosaccharides probably contributed to altered NDF content of alfalfa.
Physico‐chemical and sensory evaluation of “poundmix” from yam, cocoyam, breadfruit and plantain blends
Purpose – The purpose of this paper is to develop poundmix for reconstitution as pounded yam, from yam, cocoyam, breadfruit and plantain and to evaluate their physico‐chemical and sensory properties.Design/methodology/approach – Instant flour of the components was prepared separately and 30‐50 per cent composite blends of poundmix were formulated. The physico‐chemical, and sensory properties of the poundmix were determined and the results were subjected to appropriate statistical analysis.Findings – The swelling capacities of the poundmix are 3.14±0.03, 3.13±0.04, 3.81±0.01 per cent for 30, 40 and 50 per cent composite levels, respectively, as against 2.27±0.04 per cent for yam flour. Whole yam flour compared well with the composites in terms of peak temperatures with the 40 per cent composite flour having the highest pasting temperature 93°C and 50 per cent composite with the lowest (72°C). However, the higher the composite level the lower the peak viscosity as 390, 260, 210, and 190 BU were recorded for...