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ARS Home » Northeast Area » Beltsville, Maryland (BARC) » Beltsville Agricultural Research Center » Food Quality Laboratory » Research » Publications at this Location » Publication #368506
Research Project: Enhancing Fruit and Vegetable Nutritional Quality with Improved Phenolics Contents

Location: Food Quality Laboratory

Title: Microwave cooking increases sulforaphane level in broccoli

Author
item LU, YINGJIAN - Nanjing University Of Finance And Economics
item PANG, XINYI - Nanjing University Of Finance And Economics
item Yang, Tianbao

Submitted to: Food Science and Nutrition
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/30/2020
Publication Date: 2/4/2020
Citation: Lu, Y., Pang, X., Yang, T. 2020. Microwave cooking increases sulforaphane level in broccoli . Food Science and Nutrition. 8(4):2052-2058. https://doi.org/10.1002/fsn3.1493.
DOI: https://doi.org/10.1002/fsn3.1493

Interpretive Summary: Sulforaphane (SFR) and glucoraphanin (GLR) are anticarcinogenic compound found in broccoli. Cooking methods have been shown to affect broccoli GLR and SFR level, but little is known about the effect of lightly cooking processes on levels of these beneficial compounds. In this study, the effects of microwave and low temperature cooking on GLR and SFR contents in broccoli were investigated. Microwaving and mild heating increased the GLR and SFR level in broccoli compared to raw uncooked samples. Compared with conventional heating, microwave heating increased the GLR and SFR yield by about 80% at 50 and 60 °C. In addition, high power microwave (950 W) produced over 40% more SFR than low power microwave treatment (475 W). Hence, mild heating by microwave can increase levels of these beneficial compounds in cooked broccoli, providing potential dietary health benefits to consumers.

Technical Abstract: Sulforaphane (SFR), an anticarcinogenic compound forms from the hydrolysis of glucoraphanin (GLR) in broccoli. Cooking methods have been show to affect broccoli GLR and SFR level, but little is known about the effect of lightly cooking processes on them. In this study, the effects of microwave and low temperature cooking on GLR and SFR contents in broccoli were investigated. Both microwaving and mild heating increased the GLR and SFR level in broccoli compared to the raw samples (without any treatment). In particular, SFR level was significantly low under 40 °C, and dramatically increased from 40 to 60 °C, but nothing was detected at 70 °C. Compared with conventional heating, microwave heating increased the GLR and SFR yield by about 80% at 50 and 60 °C. Microwave power level influenced the SFR contents too. At the same temperatures (50 and 60 °C), high power microwave (950 W) with a short time produced over 40% more SFR than low power microwave treatment (475 W). Hence, mild heating by microwave could increase the GLR and SFR levels in broccoli, and high power microwave heating with temperature control at 60 °C could retain higher bioavailability of SFR and GLR in broccoli. This research provides consumers an effective cook method to achieve high nutritional quality of broccoli.