Keräsalaatin varastointi

Authors

• Irma Voipio Helsingin yliopiston puutarhatieteen laitos, Viik

DOI: https://doi.org/10.23986/afsci.71649

Abstract

The storage of lettuce was studied in 1963–65. The two principal problems were the amount of losses on lettuce during storage of one, two, three or more weeks, and how to reduce storage losses. The lettuce was grown in experimental fields at Viik (Table 1). To reduce losses during storage the lettuce was pretreated in the following ways before storing. 1. Hydrocooling by spraying with or by immersion in 2° C water for 15 minutes 2. Washing in 15° C water for 15—30 seconds 3. SD 4901 -treatment for 15—30 seconds 4. Wrapping in perforated PV-bags 5. Crushed ice treatment, 2 litres ice in each box. Each treatment consisted of 5 replications and each replication of 10 (Passe Partout, Market Favorite) or 8—10 (Great Lakes) heads. The lettuce was trimmed before the treatment and again after storage. The storage temperature was 1—2° C and the relative humidity 90—95 %. The results of the experiments are given in Tables 2 to 8. Treatments 1, 2, 3 and 4 (see above) reduced the storage losses as compared with untreated lots during storage of one and two weeks (Tables 2, 4, 5 and 6). Wrapping in PV-bags gave the best results during storage longer than two weeks (Tables 2, 6). Great differences in the keeping quality of lettuce occurred in the years 1964 and 1965. The growing season in 1964 was hot and dry, and the lettuce was irrigated several times. The rapid change in soil moisture during the hot weather may have caused the tip burn in the lettuce. Despite the stored lettuce being stored apparently healthy in 1964, after storage it proved to be affected by this disease. Summer 1965 was cool and wet and no tip burn was found in the lettuce. In 1965 the lettuce thus remained marketable in storage for a longer time than in 1964. Trimming after a storage period of two and three weeks revealed that one out of ten heads was injured by suboxidation. The damage could not be noticed on the outside.