Sun-Treated Oyster Mushroom Powder as a Vitamin D Fortificant: Effect of Baking on Vitamin D Retention in Cookies

Abstract

This study evaluated sun-treated oyster mushroom (Pleurotus ostreatus) powder as a vegetarian source of
vitamin D fortification and assessed the effect of baking on vitamin D retention in cookies. Fresh mushrooms
were cleaned, cut to a uniform size, sun-dried, converted to powder, incorporated at 10% into a cookie
formulation, and baked at 180 °C for 10 min. Vitamin D was quantified by HPLC in untreated mushroom
powder, solar-dried mushroom powder, and the baked cookies. The reported vitamin D content increased from
7.73 μg/g in untreated powder to 45.21 μg/g in solar-dried powder, confirming the enhancement associated
with sunlight exposure. Cookies prepared with 10% solar-dried mushroom powder contained 5.6 μg/g vitamin
D, with a reported retention of 90.20% after baking. These data indicate that solar-dried oyster mushroom
powder can be used as a low-cost, vegetarian fortification ingredient for baked products, while retaining most
of the measured vitamin D under the baking conditions used in this study.