STUDIES ON SHELLING OF FROZEN SWEET CORN

Abstract

ABSTRACT Commercially, the most common method of separating kernels from the sweet corn cob is by cutting the kernels with a sharp blade. This method does not allow the total removal of kernels from the cob. Approximately 20% of kernels remain on the cob. The objective of this study was to evaluate the shelling method for removal of kernels from frozen sweet corn cobs, on the base of hardness, separation rate, and share of damaged and total loss of kernels. The corn cobs prior to shelling were subjected to blanching in water and freezing by spraying liquid nitrogen. The freezing times of 2, 4 and 6 min significantly increased hardness and separation rate and decreased damage and kernels losses. Starting at 6 min there were no significant effects of increase in freezing time on average values of analyzed parameters. PRACTICAL APPLICATIONSCommercially, the most common method of separating sweet corn kernels from the cob is by cutting the kernels. The cutting operation severs the upper part of the kernel from the lower part, which remains on the cob. Thus, the hull of the kernel is broken open and part of each kernel is wasted. Furthermore, during subsequent wet‐processing, including washing and blanching of the severed kernels, part of the corn meat is leached from its pouch and lost. This work shows the new method for separation of kernels from the cob by freezing the kernels on the cob in nitrogen. The frozen cob is then subjected to impact in a threshing device. The advantage of this method is the reduction of waste and increased yield of corn. The results from this study can be used as reference for separating sweet corn in similar applications.