Reduction of Postharvest Decay of Peaches and Nectarines with Heat Treatments

Excerpts from the report: In the United States and in several other countries experiments have been conducted for many years to reduce decay of peaches from the time they are picked until they are consumed. Most decay control operations include removing field heat from the peaches as quickly as possible followed by holding or shipping the fruit at low temperatures. Hydrocooling the fruit immediately after harvest is an extremely effective way of removing field heat. However, neither hydrocooling nor short transit periods at low temperatures reduce decay of peaches during the subsequent ripening period at more moderate temperatures. It is during this period that chemicals may be useful to reduce decay. Peaches were obtained from wholesale houses in Washington, D.C., or nearby orchards. Information is given on (a) effect of water temperature and length of exposure on decay development; (b) effect of holding at 50° or 32° F. and of hydrocooling on heated peaches; (c) peach temperatures during heating and hydrocooling; (d) decay of peaches at 70° F. as affected by hot water or hot air treatments; (e) effect of hot water on decay-producing organisms; (f) the effect of hot water on decay of peaches and nectarines packaged in open and overwrapped consumer-size units.