Department of Agriculture

Permanent URI for this collectionhttps://ir.mug.edu.gh/handle/123456789/136

Browse

Browsing Department of Agriculture by Author "Budu, A. S"

Filter results by typing the first few letters
Now showing 1 - 2 of 2
  • Thumbnail Image
    Item
    Changes in some biochemical qualities during drying of pulp pre-conditioned and fermented cocoa (Theobroma Cacao) beans
    (African Journal of Food, Agriculture, Nutrition and Development, 2015-01-01) Afoakwa, E. O; Kongor, J. E; Budu, A. S; Mensah-Brown, H; Takrama, J. F
    Fermentation and drying are critical to the development of flavour precursors that generate into distinctive chocolate flavour notes during industrial manufacture. These processes also lead to reduction in acidity and free fatty acids of nibs, which dictates the levels of bitterness and colour development in chocolates. This study investigated changes in nib acidity, flavour precursors (sugars concentration and proteins) and free fatty acids during drying of pulp pre-conditioned and fermented cocoa beans using a 4 x 3 full factorial experimental design with pod storage (0, 3, 7 and 10 days) and drying time (0, 3 and 6 days) as the principal factors. Non-volatile (titratable) acidity, pH, sugars (reducing, non-reducing and total sugars), changes in protein content and free fatty acids of the beans were studied using standard analytical methods. Increasing pod storage consistently increased pH of the fermented nibs at the end of drying with consequential decrease in titratable acidity. The pH increased from 4.92 for the freshly harvested pods to 6.00 for pods stored for 10 days at the end of the drying process. Similarly, pH of the fermented beans increased with increasing drying time for all pod storage treatment except for pods stored for 10 days. The pH of fermented beans whose pods were stored for 3 and 7 days were 5.26 and 5.56 respectively after drying for 7 days. Protein, reducing sugars, non-reducing sugars and total sugars decreased significantly (p<0.05) with increasing duration of drying at all pod storage periods. Pod storage and drying significantly (p<0.05) increased the free fatty acids content of the fermented nibs. The FFAs of the dried beans increased from 0.47% for the unstored (freshly harvested) pods to 0.55% for pods stored for 3 and 7 days and 0.58% for pods stored for 10 days. However, FFAs content of all the dried fermented beans were below the acceptable limits of 1.75% oleic acid equivalent in cocoa butter at all pod storage periods. Storage of cocoa pod between 3–7 days with 7 days of drying (after 6 days fermentation) led to considerable reductions in nib acidity, reducing sugars, nonreducing, total sugars and proteins and acceptable FFA levels.
  • Thumbnail Image
    Item
    Variability In Biochemical Composition And Cell Wall Constituents Among Seven Varieties In Ghanaian Yam (Dioscorea Sp.) Germplasm
    (African Journal of Food, Agriculture, Nutrition and Development, 2013-09) Afoakwa, E. O; Polycarp, D; Budu, A. S; Mensah-Brown, H; Otoo, E
    This work characterized the most cultivated and consumed yam (Dioscorea) cultivars within the Ghanaian yam germplasm based on their biochemical and cell wall constituents to assess their potential alternative food and industrial processing applications. Samples were analyzed for their biochemical composition - starch, amylose, amylopectin, total sugars, reducing sugars and non-reducing sugars along the head, middle and tail regions of each tuber using standard analytical methods. Cell wall constituents - acid detergent fibre, neutral detergent fibre, acid detergent lignin, cellulose and hemicellulose of each tuber were also determined using standard analytical methods. The results showed no significant differences at p<0.05 in biochemical compositions along the length of the studied cultivars. D. cayenensis (Pure-yellow), D. rotundata (Pona) and D. alata (Matches) were found to have high starch contents (63.16-65.69%, 63.54-65.30% and 63.24-65.17% respectively). Amylose content was observed to vary along the length of the tubers for the varieties studied. D. alata (Matches) was observed to contain the highest amylose content of 19.66-20.64%. No identifiable trend was however, observed for the amylopectin content along the length between the varieties investigated. D. bulbifera recorded the lowest amylopectin content of 41.29%, 43.59% and 44.63% while D. esculenta had the highest with 49.84%, 50.24% and 50.13% along the tail, middle and head sections respectively. Total sugar content varied significantly (p<0.05) along the lengths of all the varieties investigated. It was higher at the tail portions for all the varieties studied than the head regions; the middle portions recorded the least. D. bulbifera recorded highest total sugar contents (4.74-4.84%) and total sucrose (3.58-3.64%). There were significant differences (p<0.05) in the cell wall constituents of the yam varieties. Cellulose was found to be the most common cell wall component with D. rotundata having the highest level of 3.36% whilst D. dumetorum had the least (1.56%). Hemicellulose content ranged between 0.42 g/100g in D. alata to 4.58 g/100g in D. esculenta whiles lignin content ranged from 1.56 g/100g in D. dumetorum to 2.87 g/100g for D. praehensalis. There were significant differences (p<0.05) in the neutral detergent fibre found in Dioscorea esculenta and the other yam species. It ranged from 1.18 g/100g in D. alata to 5.46 g/100g in D. esculenta. Less than 1% of acid detergent fibre was identified in the yam varieties, suggesting varied levels of biochemical composition and cell wall constituents in the different yam varieties.
Users are advised to duly acknowledge the right owners as provided on the works