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2018 Vol.43, Issue 3 Preview Page
September 2018. pp. 211-218

Purpose: The present study investigated the nutritional and organoleptic characteristics of two African leafy vegetables (ALVs)—jute mallow (Corchorus olitorius L) and cowpea (Vigna unguiculata)—at various drying temperatures. Methods: The thin-layer drying of cowpea leaves and jute mallow was studied at various temperatures (40–100°C) in a convective laboratory dryer, and the nutrient profiles of the dried vegetables were determined. The nutrients considered were vitamins B2 and C, and β-carotene. The level of vitamin C was determined by high-performance liquid chromatography (HPLC), whereas the levels of β-carotene and vitamin B2 were determined by titration. Results: β-carotene was the most stable nutrient, whereas vitamin C was the least stable nutrient in both cowpea leaves and jute mallow. The drying parameters—temperature and time—revealed that temperature had the most profound effect on vegetable nutrient stability. Organoleptic tests were carried out on the fresh and dried vegetable; there were no significant differences in preference between the fresh and dried ALVs (95% confidence interval). Conclusions: The present study revealed that the vegetables can be preserved by drying, and the study could be used as a guide for effective drying of those vegetables.

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  • Publisher :The Korean Society for Agricultural Machinery
  • Publisher(Ko) :한국농업기계학회
  • Journal Title :Journal of Biosystems Engineering
  • Journal Title(Ko) :바이오시스템공학
  • Volume : 43
  • No :3
  • Pages :211-218
  • Received Date :2017. 09. 26
  • Accepted Date : 2018. 06. 04