Folate content in fresh corn: Effects of harvest time, storage and cooking methods

Fresh corn is a good source of micronutrients. Here, we investigated the effects of harvest time (18-24 days after pollination), storage temperature (25 degrees C, 4 degrees C, or -20 degrees C), and cooking method (boiling, steaming, or microwave heating) on folate content and retention in fresh corn. Folate levels in the selected six fresh corn cultivars were 66.6-152 mu g/100 g fresh weight, with 5-methyltetrahydrofolate as the predominant vitamer; and the time of harvest did not significantly impact folate levels. An average folate retention of 83 % was observed in waxy corn varieties after 5 days of storage at 25 degrees C, and 77 % (average) of the folates was retained in sweet corn cultivars after 3 days of storage in a 4 degrees C refrigerator. The average folate retention was 71 % after 14 days of storage at -20 degrees C, which decreased to 40 % after 120 days. A folate reduction of 45 % (average) was observed in boiled corn, whereas steaming and microwave heating involved minor folate loss of 12 % and 15 %. These results provide insight into folate contents and retention in raw and processed corn post-harvest. Our study revealed that fresh corn is rich in active folate vitamers and is thus a promising dietary source of folates.

Automated summary

Fresh corn is a rich and stable source of folate, making it a promising dietary source of this important nutrient. Harvest time and cooking method have minimal impact on folate levels, while storage temperature affects folate retention.