This study was done to evaluate the effect of short exposure to sunlight and of heating on crude palm oil (CPO) quality particularly on its carotenoids content. Firstly, CPO was exposed to sunlight for 14 hrs. Then, samples were collected and kept at 4°C for analysis of carotenoids content, free fatty acid (FFA) and peroxide value (PV). Secondly, CPO was heated at 50°C, 120°C, 200°C or 400°C for 30 min, 60 min or 120 min and samples were cooled down and kept at 4°C until analysis of carotenoids content, FFA and PV. Finally, we studied the effect of heating of CPO in the food matrix (maize cake). Thus, maize cake was steamed on gas stove (100 ± 5°C) during exactly 1, 2, 3 or 4h and kept at 4°C until analysis of moisture and carotenoids contents. The results showed that short exposure to sunlight did not significantly affect carotenoids content, FFA and PV of CPO. However, heating accelerated the formation of peroxides and degradation of carotenoids. Destruction of carotenoids increased with both temperature and duration of exposure to heat. FFA did not significantly change during heating. Likewise, during heating of CPO in the food matrix, carotenoids content decreased significantly with cooking time. These results suggest that short exposure to sunlight does not have a significant effect on carotenoids content of CPO. But, its heating (directly or in the food matrix) results in significant degradation of carotenoids.

Iron, zinc and vitamin A deficiencies co-exist in Cameroon in all age groups. However, natural sources of vitamin A are available and could be used to meet the need of the whole population in association with iron and zinc supplementation. This study aims at assessing the serum levels of zinc and iron after 11 days of supplementation. The study enrolled 26 men (18-33 years), distributed into five groups. From the first day, they were supplemented with 20 mg of zinc and iron, taken each alone, both either together or at two different times. The five last days, participants were put on free vitamin A diets. Serums were obtained at day 1, day 5 and day 11 for Zn and Fe levels determination by atomic absorption spectrophotometry. The highest serum iron and zinc concentrations were observed in groups either supplemented with zinc or with iron given alone. In those two groups, serum Zn concentrations increased from 0.69 μg/mL ± 0.02 μg/mL to 0.95 μg/mL ± 0.13 μg/mL (group 2), from 0.48 μg/mL ± 0.06 μg/mL to 0.97 μg/mL ± 0.11 μg/mL (group 3); and serum Fe concentrations from 1.49 μg/mL ± 0.54 μg/mL to 3.49 μg/mL ± 1.01 μg/mL (group 2); and from 1.42 μg/mL ± 0.45 μg/mL to 3.41 μg/mL ± 0.81 μg/mL (group 3), respectively. Supplementation with Fe or Zn alone increased both Fe and Zn serum levels of participants. Serum levels of iron and zinc when given together or at different time were not significantly different. Further studies on a larger population are necessary to confirm that supplementation with zinc or with iron alone could raise both zinc and iron levels in serum simultaneously.

Iron, zinc and vitamin A deficiencies co-exist in Cameroon in all age groups. However, natural sources of vitamin A are available and could be used to meet the need of the whole population in association with iron and zinc supplementation. This study aims at assessing the serum levels of zinc and iron after 11 days of supplementation. The study enrolled 26 men (18-33 years), distributed into five groups. From the first day, they were supplemented with 20 mg of zinc and iron, taken each alone, both either together or at two different times. The five last days, participants were put on free vitamin A diets. Serums were obtained at day 1, day 5 and day 11 for Zn and Fe levels determination by atomic absorption spectrophotometry. The highest serum iron and zinc concentrations were observed in groups either supplemented with zinc or with iron given alone. In those two groups, serum Zn concentrations increased from 0.69 μg/mL ± 0.02 μg/mL to 0.95 μg/mL ± 0.13 μg/mL (group 2), from 0.48 μg/mL ± 0.06 μg/mL to 0.97 μg/mL ± 0.11 μg/mL (group 3); and serum Fe concentrations from 1.49 μg/mL ± 0.54 μg/mL to 3.49 μg/mL ± 1.01 μg/mL (group 2); and from 1.42 μg/mL ± 0.45 μg/mL to 3.41 μg/mL ± 0.81 μg/mL (group 3), respectively. Supplementation with Fe or Zn alone increased both Fe and Zn serum levels of participants. Serum levels of iron and zinc when given together or at different time were not significantly different. Further studies on a larger population are necessary to confirm that supplementation with zinc or with iron alone could raise both zinc and iron levels in serum simultaneously.