Mango processing with particular consideration of carotene retention and pectin recovery.
Neidhart S., Carle R.
Author Affiliation: Institute of Food Science and Biotechnology, Chair of Plant Foodstuff Technology, Hohenheim University, August-von-Hartmann-Strasse 3, 70599 Stuttgart, Germany.
Proceedings of the tropical fruits in human nutrition and health conference 2008, Couran Cove Island Resort, Gold Coast, Australia, 8-11 November 2008 : 47-59
Abstract : Plantation of perennial fruit trees could be an ecologically important alternative to erosion-prone annual crop and vegetable production systems on sloping sites in the mountainous regions of Southeast Asia. In view of market liberalisation and rising competition, the role of fruit processing in terms of a value-adding increase in productivity is no longer limited to the reduction of post-harvest losses. As an exemplar for mango fruits (Mangifera indica L.), grown in Northern Thailand, the potential of cultivars for product differentiation through the promotion of niche products with special high-quality attributes has been explored. Retention of pro-vitamin A in mango processing was investigated for various process parameters in puree production as well as in solar and conventional drying. Sulphitation, which is under critical consideration, has been avoided in fruit drying by early inactivation of browning enzymes through increased drying temperatures. Solar drying was associated with higher ?-carotene losses compared to high-temperature short-time processes. Apart from thermally induced degradation, light-induced isomerisation to 9-cis-?-carotene occurred. With the focus being on ?-carotene degradation and trans-cis-isomerisation, the effects of thermal processing steps on the nutritive value of foods were systematically studied. Because ?-carotene stability greatly depended on the physical state of the plant matrix, the chromoplast characteristics of mango mesocarp was elucidated by ultra-structural studies. Since mango peels represent ~15-18% of the total fruit weight, the disposal of waste is a challenging problem in increasing fruit processing. Therefore, the potential of mango as a source of high-quality pectin was assessed. Besides yields and composition, the gelling properties and molecular sizes of pectins extracted from mango peels of different fruit ripeness were characterised and the starch contents quantified. It has been demonstrated that mango may serve for the diversified manufacture of solid and fluid products rich in ?-carotene and techno-functional food ingredients.