NIACIN, RIBOFLAVIN, AND THIAMIN STUDIES ON DEHYDRATED PORK LOAVES ¹

Abstract

The problems of transportation and meat shortage associated with the lend-lease program of the recent war have given an impetus to research studies on dehydrated meats. Since the nutritional investigations on dehydrated meat have been of such recent date, few reports have appeared in the literature.The report here presented includes studies initiated in 1943 on the effects of temperature, container, and incorporation of soya flakes on the niacin, riboflavin, and thiamin contents of dehydrated pork loaves during storage. Rice, Beuk, and Robinson (1943) reported that dehydrated pork retained little thiamin after several weeks' storage at 48.9"C. (120'F.) and that the thiamin could be stabilized to an appreciable extent by the inclusion of a mixture consisting of cereals, milk, tomato paste, and bone meal. The unsupplemented product retained 15 per cent of the original thiamin after one week's storage at 120°F., as compared with a 74 per cent retention of thiamin in pork supplemented with non-meat solids to the extent of 33 per cent. I n later studies, Rice and Robinson (1944) indicated further that at temperatures up to 37.ZoC.(99OF.) there is little or no loss of niacin or riboflavin over a period of 219 days. Thiamin decreases more rapidly, showing some loss at 26.7"C.(8OoF.). After 219 days' storage the thiamin retention in dehydrated pork is 29 per cent, while at higher temperature there is almost complete destruction of thiamin. Rice, Beuk, Kauffman, Schultz, and Robinson (1944), in their preliminary studies, have shown that dehydrated pork and dehydrated eggs stored at or above temperatures of 37°C. (98.6'F.) lose thiamin more rapidly than certain other foods, such as dried skim milk and cereals. Dehydrated mixtures of 67 per cent pork and 33 per cent cereals or milk solids lose thiamin much less rapidly than dehydrated pork alone. The thiamin loss of the dehydrated pork was €ound to be somewhat related to the moisture level over the range of 0 to 6 per cent. Thiamin retention was not affected by storage in vacuum, nitrogen, or carbon dioxide rather than air.Products rich in carbohydrate material were shown to be the most effective stabilizing agents studied. The authors postulated that the sta-

Storage Stability of Thiamin and Riboflavin in a Dehydrated Food System

“…Both thiamin salts were subject to increased degradation with increasing moisture content. The deleterious effect of increasing moisture content on thiamin stability has also been reported by Nymon and Gortner (1948) and Bookwalter et al (1968).…”

Microbiological assay of folic acid activity in human serum

“…After recovering organisms from the freeze-dried culture using this medium, stab cultures were maintained in agar (Nymon and Gortner, 1946), transferred fortnightly and stored at 0°C. On the evening before setting up an assay, a tube of liquid medium was inoculated from a stab and incubated overnight at 37°C.…”

Dehydrated Foods, Chemical and Histological Properties of Dehydrated Meat

“…The storage of dehydrated meat produced prior to and during World War II usually resulted in loss of palatability (particularly flavor) and thiamine [13,15,17,21). Deterioration in storage was greater at higher temperatures and higher moisture content and in the presence of oxygen.…”

“…Since the end of the war only a very limited amount of study has been devoted to the product. This paper reviews briefly the chemical and histological studies made on dehydrated meat during the past 15 years.…”