Submitted to: Journal of Agricultural and Food Chemistry
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: October 12, 2004
Publication Date: December 20, 2004
Citation: Lamikanra, O., Watson, M.A. 2004. Effect of calcium treatment temperature on metabolic and biochemical changes during storage of fresh-cut cantaloupe melon. Journal of Agricultural and Food Chemistry. 69 C468:C472. Interpretive Summary: To employ calcium as a processing aid for preserving cut fruit during storage, it is necessary to have an understanding of the effect of dip solution temperature on metabolic and biochemical properties of the fruit that affect product flavor and texture. The effect of dip solution temperature on metabolic and biochemical properties of the fruit that affect product quality was determined. Changes in respiration rate and enzymatic activities over a period of 10 days of cut fruit that were dipped in calcium solutions at 4 and 22oC and stored under refrigeration were monitored. Dip solutions at the lower temperature caused a decrease in respiration rate, moisture loss, and lipase (breaks down fat causing off-flavor) activity. This processing aid, when applied at the lower temperature, looks promising in helping maintain the sensory quality of the fresh-cut fruit and improving shelf life. The information will be useful to the fresh-cut fruit industry for developing methods to improve the shelf life of cut fruits.
Technical Abstract: The effect of calcium treatment temperature on metabolic activity and activities of esterase and lipase enzymes during storage of fresh-cut cantaloupe melon was determined. Fruit dipped in calcium solution at 4 oC emitted less carbon dioxide, and consumed less oxygen during storage for 12 days at 10 oC than fruit treated with calcium at ambient temperature and untreated fruit. Dipping in calcium solution at the lower temperature prevented moisture loss during storage. Lipase activity was reduced by use of calcium solution at both temperatures, but did not affect esterase activity. Inhibition of enzymatic activity in fruit pieces treated at 4 oC was considerably higher, causing undetectable lipase activity in the freshly processed cut fruit and after storage for 24h. Viscosity of pulverized cantaloupe melon with added calcium lactate at 4 oC, was higher than fruit blended under similar conditions at ambient temperature. This effect suggests the ability of calcium to confer rigidity to the tissue components at low temperatures, possibly through improved covalent crosslinking. This effect presumably causes lipase to remain in its latent inactive form during the early stages of treated fruit storage.