Understanding losses of provitamin A after drying and storage of orange-fleshed sweetpotato (Ipomea batatas)
Bechoff, A., Tomlins, K.I., Dhuique-Mayer, C. and Westby, A. (2009) Understanding losses of provitamin A after drying and storage of orange-fleshed sweetpotato (Ipomea batatas). In: The Fifteenth Symposium of the International Society for Tropical Root Crops, 2-6 Nov 2009, Lima, Peru.Full text not available from this repository.
[Draft Abstract - from Oral Presentation]
Biofortified orange-fleshed sweet potato (OFSP) is being promoted to tackle vitamin A deficiency, a serious public health problem affecting children and pregnant/lactating women in sub-Saharan Africa. The aim of the study was to quantify and understand the factors influencing provitamin A losses in OFSP dried chips. Losses were determined after drying and storage. A preliminary pilot-scale study demonstrated that carotenoid levels were not significantly different after either solar or sun drying. Field conditions using locally-promoted varieties in Uganda and Mozambique showed losses associated with drying were less than 40%. Flour made from OFSP could therefore be a significant source of provitamin A. In contrast, storage of chips at room temperature in Uganda for four months resulted in high losses of pro-vitamin A (ca. 70% loss from the initial dried product). Low-cost pretreatments, such as blanching, antioxidants and salting, did not improve carotenoid retention during storage. To understand the cause of the losses, dried sweet potato chips were stored under controlled conditions of temperature (10; 20; 30; or 40ºC), aw (0.1; 0.3; 0.5 or 0.7) and oxygen (0 [under nitrogen]; 2.5; 10 or 21% [air]). Losses in provitamin A were the least during storage at the lowest temperature and oxygen level and at the highest humidity level. Enzymatic catabolism of beta-carotene in the flour was considered unlikely because of low peroxidase activities at low water activities and the loss of peroxidase activity during storage.
|Item Type:||Conference or Workshop Item (Paper)|
|Additional Information:|| Oral Presentation given by Aurélie Bechoff as part of Session VII - Management of biotic stresses for sustainable intensification of R&T crops. The Fifteenth Symposium of The International Society for Tropical Root Crops, held 2-6 November 2009, Lima, Peru - with theme Roots and Tubers for Sustainable Development: Issues and Strategies.  Papers were distributed on CD-ROM or via the Symposium website, without peer review at time of event. This paper was subsequently peer reviewed and published in the online Symposium Proceedings.|
|Uncontrolled Keywords:||orange-fleshed sweet potato, carotenoid degradation, drying, storage|
|Subjects:||S Agriculture > S Agriculture (General)
S Agriculture > SB Plant culture
|School / Department / Research Groups:||Faculty of Engineering & Science > Natural Resources Institute
Faculty of Engineering & Science > Natural Resources Institute > Food & Markets Department
|Last Modified:||27 Jun 2014 15:01|
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