Canning Fruit Juices. Technical Aspects

Abstract

DURINGthe past ten years, a variety of canned fruit and vegetable juices has come into popular favor. However, the first attempts to pack a fruit juice in tin containers, specifically apple cider, date back to more than twenty years ago. In general, these early efforts met with failure. The low corrosion resistance of the hot-rolled tin plate of high metalloid content (the only type of plate available at that time) imposed a limited commercial life on the product, with the result that the packing of cider in tin did not prove economically feasible.About ten years ago canned tomato juice first came into commercial production after a short period of development (39). Few other foods have received such immediate and widespread consumer acceptance. Production statistics for canned tomato juice from 1933 to date are as follows (23):

Planning Nutrition Studies

“…Work in this laboratory has indicated that ferrous iron up to 100 p.p.m. does not interfere with the indicator titration if acetic acid alone is present (10). It is therefore suggested that the original Bessey and King technique be used for estimating ascorbic acid in canned foods unless there is definite evidence that the ferrous iron content of the sample is insignificant.…”

“…In any determination of the effect of heat sterilization alone, it is also important that the product be examined soon after cooling in order to avoid any effects of storage where they may be of significance. This is particularly important in the case of glasspacked products where the decline of ascorbic acid during storage may be particularly rapid (10).…”

PILOT PLANTS. Tomato Juice Line

“…The exact reduction in size of this small line was determined by the minimal size of a representative sample of tomatoes, which was considered to be 200 pounds, and a suitable operating period of 20 to 30 minutes including time for the controls to become adjusted to the load change. The "hot break" method of processing tomato juice (9) was selected, as most of the canneries in New York State use this method and its use did not preclude a "cold break" operation when desired. In assembling this line, laboratory or pilot plant models of commercial units were purchased when available, but much of the equipment had to be specially constructed for this study.…”