The Effects of some Processing Variables on the Quality of Canned Pigeonpeas

Abstract

The effect of a number of processing variables on the quality of canned pigeonpeas was studied. Storage of the unshelled peas at 45° F. for 9 days had no appreciable effect on the quality of the canned product. The length of the blanching treatment was found to determine to a certain degree the color and turbidity of the brines. The longer the blanching treatment the clearer and less turbid are the brines. The rate of flow of make-up water to the blancher had no effect on the color and turbidity of the brine, provided the blanched peas were thoroughly washed and drained before canning. Holding-time before retorting and length of cooling of the cans had no effect on the quality of the canned product. Contact of pigeonpeas with iron, brass, or copper surfaces was found to result in brine discoloration. Excessive head-space was found to result in highly colored and turbid brines and peas discolored bluish. The type of can used, whether plain tin with C-enameled ends, or the fully enameled, had no appreciable effect on the quality of the canned product. When the pigeonpeas are blanched in calcium chloride solutions or calcium chloride is added to the can, the number of cracks in the canned peas can be reduced, but the peas become so tough as to render them inedible. The addition of 2 percent of sugar to the brine was found to have no effect on the flavor or the overall quality of canned pigeonpeas. Based on the results of the experiments reported, recommendations are given about the best process to use in canning high-quality pigeonpeas.