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Light transmissions through milk carton paperboards, milk cartons, and blow-molded polyethylene containers were measured in the 350 to 800 nm region using a Cary 17D spectrophotometer equipped with a scattered transmission accessory. The paperboards had S-shaped transmission curves and were nearly opaque to wavelengths below 400 nm. Transmission at 800 nm averaged 5-3/4, 5-1/2, 4-1/2, 3, and 3% for the Eco Pak™, half-pint, quart, half-gallon, and gallon carton paperboards, respectively. Depending on wall thickness and wavelength of incident light, polyethylene containers had from 50 to 70% transmission. The effectiveness of different colored inks in reducing light transmission was compared using printed and unprinted areas of the paperboard cartons. Yellow, orange, gold, red, brown, and black inks opacified half-gallon cartons to wavelengths below 500 nm. Light transmission was reduced throughout the visible region by black, brown, and blue inks.

The effects of 10 h of spray (water) chilling and prolonged (up to 42 d) vacuum packaged storage were evaluated on 20 pork carcasses with normal muscle quality properties. Results revealed that spray chilling did not affect (P>0.05) any of the retail properties of loin chops, and only influenced purge losses from loins after 42 d of storage. Although drip losses from loin chops during simulated retail display decreased as vacuum packaged storage increased, purge losses during storage and total purge losses were unaffected by storage time. Objective muscle color measurements indicated that vacuum packaged storage increased both the redness and yellowness of chops when placed on retail display (P<0.05). They also indicated that simulated retail display reduced the redness of all chops, increased the yellowness of fresh chops, and increased the lightness and reduced the yellowness of chops stored for extended periods (P<0.05). Increases of the vacuum packaged storage period generally increased surface discoloration on loin chops after 2 d or more of simulated retail display (P<0.05), and extended retail display increased surface discoloration on all chops (P<0.05), regardless of the chilling treatment employed. Retail appearance of loin chops also deteriorated (P<0.05) as vacuum packaged storage and time of retail display was increased. Although storage time did not affect (P>0.05) the pleasantness of off-odors from loin chops when they were placed on retail display, the incidence of off-odors increased and the pleasantness of off-odors decreased (P<0.05) from chops after 5 d of display when vacuum packaged storage was prolonged. Significant (P<0.05) treatment differences were not observed in retail case-life after any of the storage intervals evaluated. However, chops from spray chilled carcasses usually had a shorter retail case-life than conventionally chilled counterparts indicating that a slight reduction in retail case-life may result from spray chilling. In addition, retail case-life decreased (P<0.05) with storage time, regardless of the chilling treatment utilized.

Light transmissions through white and yellow pigmented polyethylene milk bottles were measured in the 350- to 800-nm region. The bottles were opaque below 400 nm. Light transmission at 550 nm was 13 and 17% for the white and yellow pigmented bottles, respectively, compared to 72 and 2% for an unpigmented polyethylene bottle and a paperboard milk carton, respectively. The 400- to 550-nm wavelengths, which apparently are harmful to milk quality, were not entirely blocked by the pigmented bottles. A plastic sleeve for fluorescent tubes in dairy cases was opaque below 385 nm and had 92% transmission in the 440- to 800-nm region.