Chemical composition and effect of processing on oxalate content of taro corms

Chemical composition and effect of processing on oxalate content of taro corms

Emmanuel Ohene Afoakwa, Samuel Sefa-Dedeh, EK Agyir-Sackey

The chemical composition as well as the effect of processing on the corms of two Xanthosoma sagittifolium species and Colocasia esculenta corms were evaluated. A 3x3 factorial experimental design with cocoyam varieties (Xanthosoma (white-flesh), Xanthosoma (red-flesh) and Colocasia) and corm section (distal, middle and apical) was performed to determine the chemical composition of the corms. Oxalate content of the various corms were also evaluated and the effect of processing assessed using standard analytical methods. The mean values of the proximate composition of the three cocoyam species evaluated were; crude protein 2.98-5.50 g/100g, total fat 0.28-0.97 g/100g, ash 1.56-2.98 g/100g, starch 12.23-36.04 g/100g and crude fibre 1.11-3.00 g/100g. The apical section of all the species had high protein content while the distal section had high levels of ash, fibre and minerals. Potassium, zinc, magnesium and phosphorus were the most abundant minerals. Oxalate compositions of the fresh samples were in the range of 253.49-380.55 µg/100g for the Xanthosoma sagittifolium (red-flesh), 302.19-322.82 µg/100g for the Xanthosoma sagittifolium (white-flesh) and 328.4-459.85 µg/100g for the Colocasia esculenta. No significant differences (p< 0.05) were found between the oven-dried and solar-dried samples. However, drum drying reduced the oxalate levels by approximately 50% to average levels ranging from 99.94-191.16 µg/100g, implying that solar, oven and drum drying techniques can be used for the development of marketable dehydrated products from taro with reduced oxalate contents.

2003

https://scholar.google.com/citations?view_op=view_citation&hl=en&user=EZuX1N8AAAAJ&cstart=100&pagesize=100&citation_for_view=EZuX1N8AAAAJ:wuYnf3tzzDUC

English