Storage and Shelf Life of Packaged Watercress, Parsley, and Mint

Storage and shelf-life tests were conducted with watercress, parsley, and mint grown in Ohio, Pennsylvania, and Florida. The vegetables were trucked under container and top ice to the Washington, D.C., area, where they were purchased the day after harvest and hauled to Beltsville, Md., for testing. In packaging tests before storage, watercress and mint held up well at 0° C and 95 percent relative humidity for up to 4 weeks in perforated polyethylene bags but only 4 days in naked bunches, whereas at 20° and 60 percent relative humidity they held up for only 2 and 4 days, respectively, in polyethylene bags and 1 day or less in naked bunches. In limited storage tests using container and top ice, watercress and parsley held up well for 2 to 3 weeks and mint for 2 weeks at 0° C. After crate storage and subsequent packaging in polyethylene bags, the bunches of parsley remained salable at 0° C for 21 to 36 days beyond 4 weeks' storage and up to 14 days beyond 8 weeks' storage. At 10°, bunches in polyethylene remained salable for 4 to 6 days beyond the 4 and 8 weeks' storage. Parsley bunches packaged after 0° storage in cartons or crates with container and top ice had longer shelf life than bunches from containers stored dry without ice. Data are included on weight loss and wilt for the three greens. Respiration rates were highest for parsley, next for watercress, and lowest for mint. Initial reduced ascorbic acid content was about 48, 93, and 34 mg per 100 grams, respectively, for watercress, parsley, and mint. Reduced ascorbic acid content of parsley dropped during storage and shelf life. Higher losses of ascorbic acid were associated with higher holding temperatures and higher weight, turgor, and general appearance losses.