Main Health-Promoting Compounds Response to Long-Term Freezer Storage and Different Thawing Methods in Frozen Broccoli Florets

The effects of long-term freezer storage and different defrosting methods on the retention of glucosinolates, vitamin C, and total phenols in frozen broccoli florets were investigated in the present study. Frozen broccoli florets were stored in a freezer at −20 °C for 165 days or subjected to defrosting by three different house-hold thawing methods (water, air, and refrigerator defrosting). Results showed that all glucosinolates were well preserved, while vitamin C and total phenols were reduced by less than 12% and 19% of the control, respectively, during the storage. Besides, refrigerator and air defrosting were better than water defrosting in glucosinolates retention, and refrigerator defrosting was the best in vitamin C preservation. No difference was observed in reserving phenolic compounds among the three methods. In conclusion, long-term freezer storage is an excellent way to preserve broccoli florets, and refrigerator defrosting is the best way to maintain the nutritional compounds in frozen broccoli florets.