Solar and tray-drying methods and physicochemical properties of sweetpotato starch

Two drying methods were investigated to determine if drying is possible without affecting the quality of starch. The drying methods were solar dryer (53-55 °C) and electrically powered tray dryer (60 °C). The physicochemical properties of starch from five sweetpotato were evaluated after dehydration using the two methods. The results showed that drying methodshad effect on some physicochemical properties of sweetpotato starch. The tray-dried starches had higher moisture, ash, viscosity, and L* values. The swelling power and solubility values for tray-dried starches were significantly different from solar-dried ones, except for the tray-dried “Sauti” starch. Although the water binding capacity and amylase content were higher in solar-dried starches relative to tray-dried starches, statistically therewas no significant difference(

Proximate composition and basic phytochemical assessment of two common varieties of Terminalia catappa (Indian Almond).

Terminalia catappa is a common tree found in Ghana but it is much underutilized. The objective was therefore set to investigate the medicinal and nutritive potential of two common varieties of the plant; the red and yellow varieties. The proximate composition of the nut and pulp of the two varieties were determined using certified methods of the Association of Official Analytical Chemists. Phytochemical screening was also determined using standard screening methods. The red nut had a moisture content of 31.05%; crude fat, 36.9%; protein, 22.19%; ash, 2.76%; carbohydrate, 5.24% and crude fibre, 1.86%. The pulp contained up to 81.96% moisture; 0.04% crude fat; 1.07% protein; 1.47% ash; 14.05% carbohydrates and 1.41% crude fibre. The moisture content constituted 32.06% of the nut of the yellow variety, crude fat was 35.69%; protein, 23.05%; ash, 2.68%; carbohydrate, 4.92% and crude fibre, 1.6%. The pulp of the yellow variety had the proximate composition as: moisture, 84.37%; crude fat, 0.05%; crude protein, 1.54%; ash, 1.62%; carbohydrate, 11.03%; crude fibre, 1.39%. The pulps of both varieties were found to contain saponins, general glycosides, flavonoids, alkaloids, anthraquinones and anthraquinone glycosides. The nut of the yellow variety had terpenoids and steroids present in it while the nut of the red variety had alkaloids present. Statistical analyses carried out showed that there were no significant differences (p≤0.05) between the two varieties based on their proximate composition

Principal components analysis and age at harvest effect on quality of gari from four elite cassava varieties in Ghana

Four elite cassava varieties in Ghana released under the local names Afisiafi, Tekbankye, Abasafitaa and Gblemoduade were planted in June and harvested the following year at 9, 10, 11, 12, 13, 14 and 15months after planting, and processed into gari. The effect that age at harvest had on selected physicochemical properties indicative of gari quality was studied in the four varieties. The parameters studied include moisture content, ash, pH, titratable acidity (% lactic acid), crude fibre, swelling capacity and yield. Moisture was between 9.54 - 11.57% while ash was between 0.88 - 1.39%. Titratable acidity was between 0.85 - 1.62% while pH ranged between 3.58 and 4.21. Swelling capacity was slightly below 3 while yield ranged between 12 and 26%. The four principal components identified were dry matter, extent of fermentation, starch content and elemental composition of the gari. Age at harvestsignificantly affected (p < 0.05) moisture, pH and bulk density of the gari samples. Varietal effect was not significant

Profitability of bioethanol production using cassava (Manihot esculantus Crantz) and sweet potato (Ipomea batatas) as raw material

Ethanol imports into developing countries such as Ghana over the past decade have been on the increase. Corn, sugarcane and wheat are major crops that are normally used globally to produce bioethanol. The use of cassava and sweet potato as raw materials for ethanol production has also been demonstrated. Cassava and sweet potato, which grow excellently in Sub-Saharan Africa, could therefore be used as excellent and readily available local raw material for ethanol production to replace the seventy (70) million litres and more of ethanol imported into Ghana in 2016 for various uses. The search for the optimum processing conditions to hydrolyse and ferment sugars from the starches in cassava and sweet potato had been the major focus of all the studies in the past. The price of ethanol produced with cassava and sweet potato compared to the price of ethanol produced with other feedstock in the global market would largely determine the competitiveness and sustainability of producing ethanol with cassava and sweet potato. The objective of this work is to evaluate the cost benefits of ethanol production using cassava and sweet potato as raw materials. Sika bankye (cassava variety) and Apomuden (sweet potato variety) were cultivated and harvested at ten (10) months and three (3) months maturity respectively for the study. Liquefaction, saccharification and fermentation of the cassava and sweet potato varieties to produce ethanol were carried out with Liquozyme SC DS, combination of Spirizyme Fuel and Viscozyme L and Bio-Ferm XR (Lallemand) yeast, respectively. The study indicates that the production of ethanol with a 1:1 mixture of cassava and sweet potato using a 10,000 litres per day capacity ethanol distilling plant generates a net profit of between 9% and 30% over a period of five years. The findings indicate that ethanol production with cassava and sweet potato is a profitable venture

Pectin isolation and characterization from six okra genotypes

Pectin was isolated by aqueous extraction at pH 6.0 from the pods of six different okra genotypes (Abelmoschus esculentus L.). Genetic diversity was determined using fragment length analysis (FLA) of ten simple sequence repeat (SSR) markers. Physical and chemical evaluation of pectin was performed by means of FT-IR and NMR spectroscopy, sugar composition analysis (GC-MS), size exclusion chromatography coupled to multi-angle laser light scattering (SEC-MALLS), dilute solution viscometry and steady shear rheology assisted by principal component analysis (PCA). Each of the SSR markers detected on average 4.1 alleles and revealed unique genotypes for each sample. Extraction yield was between 11 and 14% resulting in pectin with galacturonic acid content between 43 and 63%, low degree of methyl-esterification (17–25%) and high degree of acetylation (20–40%). All samples were of high weight-average molar mass (Mw) (700–1700 × 103 g mol−1) and sugar composition analysis revealed the structural diversity of samples with HG/RG-I ratios ranging between 1.3 and 3.1. The present work shows that individual okra genotypes provide pectin with different structural properties that could potentially provide a new source of functional pectin for the food or pharmaceutical industries