Vitamin D2 formation from post-harvest UV-B treatment of mushrooms (Agaricus bisporus) and retention during storage.
The objectives of this research were to study the effects of high intensity (0.5, 0.75, and 1.0 mW/cm (2)), dose (0.5, 1.0, and 1.5 J/cm (2)), and postharvest time (1 and 4 days) on the vitamin D 2 formation in Portabella mushrooms ( Agaricus bisporus) as a result of UV-B exposure, as well as the vitamin D 2 degradation in treated mushrooms during storage. Within each intensity application, dose had the largest effect where more exposure converted more vitamin D 2 from ergosterol. Similar dose across each intensity application resulted in similar vitamin D 2 concentration. Practical commercial production requires as short a treatment time as possible, and intensity was a major factor from this standpoint where the time it took to achieve a similar vitamin D 2 concentration for similar dose exposure was significantly reduced as intensity increased. By using an intensity of 1.0 mW/cm (2) at a dose of 0.5 J/cm (2), the concentration of vitamin D 2 produced was 3.83 microg/g dry solids of mushrooms in 8 min, whereas using an intensity of 0.5 mW/cm (2) at a dose of 0.5 J/cm (2), the concentration of vitamin D 2 produced was 3.75microg/g dry solids of mushrooms in 18 min. Also, postharvest time did not have a significant effect on vitamin D 2 formation in mushrooms that were treated 1 and 4 days after harvest. Vitamin D 2 degraded in treated mushrooms during storage by apparent first-order kinetics, where the degradation rate constant was 0.025 h (-1). The information provided in this study will help mushroom producers develop commercial-scale UV treatment processes to add value to their crop while improving consumer health.
Western Regional Research Center, Agricultural Research Service, United States Department of Agriculture, 800 Buchanan Street, Albany, California 94710, USA. jsrob25@hotmail.com
John S
JS
Roberts
Arnaud
A
Teichert
Tara H
TH
McHugh
D000364:Agaricus / Q000737:chemistry / Q000378:metabolism* / Q000528:radiation effects*; D004307:Dose-Response Relationship, Radiation; D005519:Food Preservation; D007700:Kinetics; D013997:Time Factors; D014466:Ultraviolet Rays; D014807:Vitamin D / Q000032:analysis* / Q000096:biosynthesis*
D014807:Vitamin D