Lettuce, a major vegetable crop in the U.S., is second in tonage and value to potatoes. In 1972, 250,000 acres produced more than 48,000,000 cwt, with a farm value of over $250 million and a market value exceeding $1.3 billion. Lettuce is available throughout the year and its annual per capita consumption of about 22 lbs is increasing slightly.
Of the four types grown commercially in the U.S. – i.e. crisphead (iceberg), butterhead, cos (romaine) and looseleaf, the·crisphead type is the most important. This is the usual “head lettuce” or “iceberg lettuce” found in the market.
Lettuce value increases about 10-fold between field and consumer, or approximately 4-fold between shipping point and retail store. Therefore, losses at destination are especially costly and represent not only loss of food but also wastage of all inputs of. labor, energy and materials required for harvesting, packaging, transport, and distribution. A study in the New York area during 1967 to 1969 showed lettuce losses to average 4.1, 4.6, and 7.1% at wholesale, retail, and consumer levels (1). Total loss would presumably approximate the sum of the latter two figures (i.e., 11.7%) and would reflect only quantitative losses.
This paper reviews general procedures and practices of handling lettuce and evaluates them in light of commodity requirements and responses; emphasis is on the crisphead type. For a summary of some physical and biological characteristics related to head lettuce see appendix.
Citation: Symposium, ASHRAE Transactions, Volume 80, Part 1, Los Angeles, CA
Product Details
- Published:
- 1974
- Number of Pages:
- 9
- File Size:
- 1 file , 630 KB
- Product Code(s):
- D-LA-74-06-2
