Postharvest Biology and Technology 17 (1999) 1 – 9 Modified atmosphere packaging for mixed loads of horticultural commodities exposed to two postharvest temperatures Filipa M. Silva a,1 , Khe V. Chau a , Jeffrey K. Brecht b, *, Steven A. Sargent b a Agricultural and Biological Engineering Department, Uniersity of Florida, Gainesille, FL 32611 -0570, USA b Horticultural Sciences Department, Uniersity of Florida, 1143 Fifield Hall, P.O. Box 110690, Gainesille, FL 32611 -0690, USA Received 16 June 1998; received in revised form 7 April 1999; accepted 17 April 1999 Abstract A procedure to maintain desired levels of O 2 and CO 2 inside packages that are exposed to different surrounding temperatures was designed and tested. This procedure included the design of packages for a high temperature, ambient atmosphere conditions simulating retail display conditions and the use of a controlled atmosphere (CA) environment surrounding the packages at a lower temperature simulating storage or transport conditions. To test the concept, strawberries and snap beans were held at 7°C for 4 days and 19°C for 2 days to simulate mixed storage/transport and retail display at these respective temperatures. The strawberries were stored in jars fitted with a short tube to modify the interior atmosphere; snap beans were stored in commercially available, semipermeable plastic bags. Both package types were placed in a CA of 14.8% O 2 plus 8.3% CO 2 at 7°C followed by storage in air at 19°C. Under these conditions, it was possible to maintain atmospheres that were close to the desired atmospheres for the products at both temperatures. © 1999 Elsevier Science B.V. All rights reserved. Keywords: Mixed loads; Modified atmosphere packaging; Temperature; Controlled atmosphere; Strawberries; Snap beans; Storage; Transport; Retail display; Plastic bags; Tubes; Container www.elsevier.com/locate/postharvbio 1. Introduction Fresh fruits and vegetables are perishable living tissues that continue to respire after harvest. The problem of spoilage of fresh fruits and vegetables is aggravated when commodities need to be shipped to distant markets. One way to reduce this problem and extend the shelf life of perish- ables is by promptly cooling and maintaining the produce at low temperatures (Ryall and Lipton, 1979; De Wel et al., 1982; Mitchell, 1992). An- other technique, especially as a complement to temperature management, is modification of the atmosphere surrounding the product to create a new atmosphere that usually has a lower level of * Corresponding author. Fax: +1-352-3926479. E-mail address: jkb@gnv.ifas.ufl.edu (J.K. Brecht) 1 Present address: Escola Superior de Biotecnologia, Rua Dr. Anto ´ nio Bernardino de Almeida, 4200 Porto, Portugal. 0925-5214/99/$ - see front matter © 1999 Elsevier Science B.V. All rights reserved. PII:S0925-5214(99)00026-5