Author(s): Conrad O. Perera*, | Viraj J. Jasinghe
doi: 10.1616/1750-2683.0053
Print ISSN: 1750-2683 | Electronic ISSN: 1750-2691
Volume: 3 | Issue: 1 Introduction to special issue on Process Optimisation
Cover date: February 2010 Page(s): 57-67
The ergosterol content in different mushrooms varies significantly from tissue to tissue as well as from mushroom to mushroom. The highest levels of ergosterol, the precursor of vitamin D2, are found in the gills (lamellae), followed by the outer cap (pileus) and the stem. The conversion of ergosterol in mushrooms to vitamin D2 by exposure to UV light is significantly affected (P < 0.01) by the orientation of the mushroom tissues to the UV source. The highest vitamin D2 content is found in oyster mushrooms (Pleurotus ostreatus) exposed to UV-B light at 35°C and around 80% moisture. On the other hand, under the same conditions, the lowest vitamin D2 content is observed in button mushrooms (Agaricus bisporus). The highest conversion rate is found in oyster mushrooms followed by shiitake (Lentinula edodes) and abalone (Pleurotus cystidus), whereas the lowest conversion rate is observed in button mushrooms. Both initial moisture content and temperature of UV exposure influence the conversion of ergosterol, which follows zero-order kinetics.
Author(s): Conrad O. Perera*, | Viraj J. Jasinghe
Food Science, Department of Chemistry, The University of Auckland, Private bag 92019, Auckland, New Zealand. E-mail: conradperera at gmail.com