This study was performed to investigate the effects of different cooking methods (boiling, roasting, stir-frying, and deep-frying) on folate retention in 6 kinds of mushrooms (Beech-, button-, Juda’s ear-, oak-, oyster-, and winter-mushrooms) frequently consumed in Korea. In order to assure reliability of analytical data, trienzyme extraction-L casei method was verified and analytical quality control was also evaluated. Folate contents of mushrooms varied by 6.04-64.82 g/100 g depending on the type of mushrooms. and were significantly affected by cooking methods. Depending on cooking methods, folate contents of mushrooms decreased by 22-48%, 2-31%, and 17-56% for Juda’s ear-, oak- and oyster-mushrooms, respectively, while 17-90% of folate was increased in Beech mushroom. Overall, the largest weight loss was found in boiled mushrooms, but the lowest one in deep-fried samples. True folate retention rates considering processing factor were less than 100% for all cooked mushrooms except for Beech samples. Overall, folate loss was the largest by boiling with water but the smallest by deep-frying. Both accuracy and precision of trienzyme extraction-L-casei method were excellent based on a recovery close to 100% and coefficient variations less than 3%. Quality control chart of folate analysis (n=26) obtained during the entire study and an international proficiency test (z-score=-0.5) showed that trienzyme extraction-L casei method is reliable enough for production of national folate database.

• Su-Jin Park(Department of Food Science and Technology, Sunchon National University, 순천대학교 식품공학과) | 박수진
• Sun-Hye Park(Department of Food Science and Technology, Sunchon National University, 순천대학교 식품공학과) | 박선혜
• Heajung Chung(Department of Korean Cuisine, Jeonju University, 전주대학교 한식조리학과) | 정혜정
• Junsoo Lee(Department of Food Science and Biotechnologe, Chungbuk National University, 충북대학교 식품생명공학과) | 이준수
• Taisun Hyun(Department of Food and Nutrition, Chungbuk National University, 충북대학교 식품영양학과) | 현태선
• Jiyeon Chun(Department of Food Science and Technology, Sunchon National University, 순천대학교 식품공학과) | 천지연 Corresponding author