Investigating carotenoid loss after drying and storage of

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1. Literature review
Volatile products have been described from the degradation of β-carotene in its chemical
form (Handelman et al. 1991; Mordi et al. 1993; Waché et al. 2003); or from
carotenoids naturally present in, for instance, oak wood (Nonier et al. 2004), black tea
(Ravichandran et al. 2002), and wine (Mendes-Pinto 2009). Norisoprenoids have also
been reported from paprika powder (Cremer and Eicher 2000). But to our knowledge no
work has been reported on the degradation pattern of β-carotene from dried root or tuber
crop such as sweet potato.
1.4 INFLUENCE OF DRYING AND STORAGE ON CAROTENOID LOSS IN
SWEET POTATO ROOTS
1.4.1 Introduction
Following the understanding of the mechanisms of carotenoid degradation, the
quantification of carotenoid losses could help define which processes and conditions
contribute the most.
In OFSP, initial levels of carotenoids are influenced by variety, root maturation and
location (Kósambo et al. 1998). Sweet potato varieties can be grouped into four general
categories based on their β-carotene content on a dry weight basis (Simonne et al. 1993):
- non- detectable 130 µg.g -1 ;
The carotenoid content after processing is dependent on the initial content and loss
during processing..
1.4.2 Determination of carotenoid degradation
Losses
Quantifying carotenoid losses after processing is a simple means to classify the best
processes and optimise the chosen processes. There are two ways of calculating
carotenoid loss (Equations 1-1 and 1-2):