Effect of Commercial Curing, Smoking, Storage, and Cooking Operations Upon Vitamin Content of Pork Hams

Abstract

Although there have been numerous reports on the extent to which vitamins are retained in meats during different methods of home cooking, there have been few published investigations of the effect of commercial curing and smoking processes. Since a large percentage of the pork consumed in this country is either cured or cured and smoked, information regarding the retention of vitamins during these operations is essential for a complete understanding of the possible losses during marketing and preparation of pork for consumption. Schweigert, McIntire, and Elvehjem ( 1943) have published data indicating that during the curing and smoking of a single ham the retentions of thiamin, riboflavin, and niacin were 73, 92, and 84 per cent, respectively. Unfortunately, these percentages of retention were calculated on a basis of the residual solids (i.e., free of fat and moisture) of companion hams, one being sampled before and the other after curing and smoking. Such a basis for calculation did not take into account the presence of the considerable quantity of curing salts which must have appeared in the residual solids of the cured and smoked ham but not in the fresh ham. Revised calculations and additional data obtained by these workers, Schweigert, McIntire, and Elvehjem (1944), indicated that the actual retentions during curing and smoking were 10 to 20 per cent higher than the earlier report, being 80 to 85 per cent for thiamin, 97 to 106 per cent for riboflavin, and 100 to 107 per cent for niacin.The series of experiments here reported has been conducted in such a manner that the retention of vitamins during each operation commonly carried out in the commercial processing of hams can'be determined as well as the over-all retention after a series of such operations. The processes that have been investigated are curing, smoking, storage of smoked hams prior to sale, storage of cured hams in freezers with subsequent smoking, and the preparation of cooked hams. I n addition, the effects of roasting fresh hams and smoked hams has been investigated in order to compare the over-all effect of curing-smoking-roasting to that of roasting fresh ham. These studies were conducted in three series as described below. EXPERIMENTAL PROCEDUREExperiment 1: Eighteen pairs of companion hams, U. S. Good in quality, were obtained directly from the pork -processing factory, weighed, numbered, and divided into sets of right and left hams. Slices two inches in thickness were cut from the center of each of the left hams. Each slice was trimmed free of visible fat and bone, ground, frozen, and stored a t 239 Containing salt, sugar, nitrate, and nitrite in proportions conforming to U. S. Department of Agriculture, Bureau of Animal Industry regulations.

The effect of processing on the nutritive value of flesh foods

“…The curing of meat has been reported so far to produce only small reductions in nutritive value. Rice, Beuk & Fried (1947) found small losses (1-5%) of thiamin, riboflavin and nicotinic acid in cured meat. An increased thiamin loss occurred (15-200/0) if the product was smoked and no doubt this is attributable to the heat lability of this vitamin, as the losses of riboflavin and nicotinic acid remained low.…”