Browsing by Author "Adu-Poku, David"

Now showing 1 - 3 of 3
  • No Thumbnail Available
    Item
    Antinutrient contents of watermelon seeds
    (MOJ Food process Technol., 2018) Addo, Philip W.; Agbenorhevi, Jacob K.; Adu-Poku, David; 0000-0002-8516-7656
    However, previous studies have shown watermelon seeds as considerable source of food for human nutrition and health. In the present study, seeds of three (3) varieties of watermelons (Kaolak, Crimson sweet and Sugar baby) were analysed for their moisture content and antinutrients; oxalate, phytate and tannin levels. The oxalate, phytate and tannin contents were determined by means of potassium permanganate titration method, Iron (I) chloride titration method and Folin‒Ciocalteau assay, respectively. The seeds were also boiled‒oven dried and roasted to determine the effects of the processing on the antinutrient levels. Results indicated that the fresh watermelon seeds had moisture content in the range of 10.81‒12.04%; oxalate, 0.43‒0.48 g/100g db; phytate, 0.23‒0.30 g/100g db and tannin, 5.06‒6.45 g/100g db. The boiling‒oven drying and roasting significantly reduced the levels of the antinutrients. Decrease in the oxalate levels was in the range of 92‒96% for boiled‒oven dried samples and 49‒64% for roasted samples. Decrease in the phytate levels ranged 58‒76% and 73‒82% for boiled‒oven dried and roasted samples, respectively. However, decrease in the tannin levels ranged 15‒35% for boiled‒oven dried samples and 23‒38% for roasted samples. The present findings suggest watermelon seeds contain antinutrients which are minor components and can be reduced by boiling and roasting of the seeds.
  • No Thumbnail Available
    Item
    Modeling the Kinetics of Potassium Diffusion in Estima Potato under Different Leaching Conditions
    (International Journal of Food Science, 2020) Adu-Poku, David; Saah, Selina A.; Agbenorhevi, Jacob K.; 0000-0003-2518-3977; 0000-0002-0585-2144; 0000-0002-8516-7656
    The diffusion of potassium in potato (Solanum tuberosum) at different leaching conditions was investigated. Two modes of pretreatment of potato samples (cubes and spheres) by preheating to 80° C and leaching at temperatures of 20-80° C were performed using a temperature- and agitation-controlled batch extractor. A Fickian model incorporating the effective diffusion coefficient (Deff), partition coefficient (K) between the solute concentration in the potato and medium, and mass transfer coefficient (kl) was developed to simulate and predict the fraction of potassium leached from the potato at any temperature. Results showed significant reduction in activation energies from 92 to 25.02 kJ/mol for cubes and from 75.02 to 13.40 kJ/mol for spheres culminating in higher extraction rates when samples were preheated to 80° C. The Deff , K, and kl values obtained were in the range of 0:02 − 7:33 × 10−9 m2/s, 0:63 − 8:00 × 10−2, and 0:01333:00 × 10−4 m/s, respectively. The kinetic parameters showed a change in slope or discontinuity in the gelatinization temperature range as a function of temperature, an indication of a change in the diffusional matrix. The optimum operating conditions were 80° C preheating and leaching at temperatures up to 50° C. The proposed mathematical model offered a satisfactory description of both dynamic and equilibrium mass transfers of potassium by adequately predicting the fraction of potassium from potato cubes and spheres. The present findings could be useful in the pretreatment of potato for renal patients.
  • No Thumbnail Available
    Item
    Nitrite Assessment of Processed Meat Products Commonly Consumed in Ghana
    (Journal of Food Security, 2019) Duah, Joyce; Agbenorhevi, Jacob K.; Adu-Poku, David; Antwi, Francis O.; 0000-0001-5009-3477; 0000-0002-8516-7656; 0000-0003-2518-3977
    Sodium and potassium salts of nitrite are used in meat products as preservative, antioxidant and colour fixative. However, high levels of these chemicals pose risks such as toxicity due to the formation of nitroso compounds originated from nitrite sources. The present study was conducted to assess the nitrite residual levels and to evaluate the health risk of consumers from exposure of nitrite in commonly consumed processed meat products (sausage, corned beef and bacon) on the Ghanaian market. A total of 300 questionnaires were administered to various age groups in the study population in the Ayawaso West Sub Metro, Accra. Participants were made to fill out the 24 h food frequency questionnaire. Fifty (50) different types and brands of processed meat products were randomly selected and analyzed for nitrite residues by spectrophotometric method. The effect of boiling, frying and grilling as cooking methods commonly employed were investigated. The mean nitrite content in the samples was 139.85 mg/kg and the mean daily intake estimated at 114.89 mg/kg/day. Significantly, the nitrite levels found in this study was higher than the WHO/EU recommended levels of 125 mg/kg in processed meat. First order Monte Carlo simulation at 10,000 iterations estimated chronic daily intake of nitrite as 5.05 mg/kg/day. Subsequently, the average risk of consumption of processed meat within the limits of reference dose of nitrite (0.33 mg/Bw/day) for the studied population was estimated at 15.65 (>>1) indicating of adverse health effect to the consumers. Overall, boiling was safer cooking method for cured meat and sausages found on the Ghanaian market.