Use of Multi-response Modelling to Investigate Mechanisms of β-Carotene Degradation in Dried Orange-Fleshed Sweet Potato During Storage: from Carotenoids to Aroma Compounds
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In order to give insight into β-carotene degradation mechanism during the storage of dried orange-fleshed sweet potato, and particularly into the role of isomers and norisoprenoids formation, multi-response kinetic modelling was applied. Determination of degradation compounds were carried out by HPLD-DAD and SPME-GC-MS as a function of time between 10 and 40 °C and at four water activities from 0.13 to 0.76. Kinetic modelling was developed assuming first-order reactions and by using mass balance. Eight compounds, namely, two isomers (9-cis- and 13-cis-β-carotene), two β-carotene epoxides (β-carotene 5,6 and 5,8 epoxide) and four volatile compounds (β-cyclocitral, β-ionone, 5,6-epoxy-β-ionone and dihydroactinidiolide), were integrated into two theoretical reaction schemes. The different models were discriminated according to goodness of fit to experimental data. This work showed that: (1) the formation of cis-isomers from β-carotene preceded oxidation, (2) β-cyclocitral arose directly from β-carotene scission while the other norisoprenoids resulted from β-carotene epoxide degradation, (3) cis-isomers were high reactive compounds. Temperature had a major influence on reaction rates k while water activities only impacted k at values under 0.51. Therefore, multi-response modelling is not only a tool to predict β-carotene degradation but a interesting way to select the appropriate degradation scheme based on the different options presented in literature.
KeywordsMulti-response modelling Reaction scheme Isomers Norisoprenoids β-carotene epoxides Rate constant
The authors thank HarvestPlus and DESI-funding from CIRAD for supporting the PhD thesis that generated the data that were used for this mathematical modelling. The views expressed are however those of the authors.
- Bechoff, A. (2010c) Investigating carotenoid losses after drying and storage of orange-fleshed sweet potato. Natural Resources Institute, University of Greenwich.Google Scholar
- Bechoff, A., Westby, A., Owori, C., Menya, G., Dhuique-Mayer, C., Dufour, D., et al. (2010b). Effect of drying and storage on the degradation of total carotenoids in orange-fleshed sweetpotato cultivars. Journal of the Science of Food and Agriculture, 90, 622–629.Google Scholar
- Bechoff, A., Tomlins, K. I., Dhuique-Mayer, C., Dove, R., & Westby, A. (2011) On-farm evaluation of the impact of drying and subsequent storage on the carotenoid content of orange-fleshed sweet potato. International Journal of Food Science & Technology, 46, 52–60.Google Scholar
- Gill, E. P., Murra, W., & Wright, M. H. (1981). Practical optimisation. New York: Academic Press.Google Scholar
- Huet, S., Jolivet, E., & Messéan, A. (1992) La régression non-linéaire: méthodes et applications en biologie. Paris.Google Scholar
- Lan, C.-H. (2011). Stability of carotenoid extracts of Cucurbita maxima towards enzymatic cooxidation and aroma compound generation. IPCBEE, 7, 141–143.Google Scholar
- Marx, M., Stuparic, M., Schieber, A., & Carle, R (2003) Effects of thermal processing on trans-cis-isomerization of β-carotene in carrot juices and carotene-containing preparations. 83, 609–617.Google Scholar