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Four commercial rosemary oleoresin preparations were added to ground chicken thigh meat at the recommended levels of the manufacturer then packaged in 80% O(2)-20% CO(2) modified atmosphere trays. The rosemary preparations differed in oil and water solubility, dispersion properties, or both. Addition of rosemary to ground chicken had an overall positive effect on raw meat appearance during storage and cooked meat flavor. No effect on bacterial growth was observed due to rosemary addition. However, oxidation was slowed in meat with added rosemary as indicated by lower TBA values, lower hexanal concentrations, and sensory scores. Color (redness) was more stable in meat with added rosemary compared with meat without rosemary, as reflected in redness (a*) values, hue angles, and visual scores. Of the 4 rosemary preparations tested, the oil-soluble, most concentrated preparation (HT-O) was most effective in maintaining meat quality compared with the other 3 types tested.

Viscoelastic, thermal, and microstructural properties of plasticized soy protein isolate (SPI) films processed by thermal compaction are discussed. Thermogravimetric analysis indicates that protein films exhibit substantial thermal degradation at temperatures above 180°C and that the processing temperature limit is about 150°C. Dynamic mechanical analysis indicates the existence of multiple glass transition temperatures associated with glycerol-and protein-rich phases. Scanning electron micrographs of the cross-sections of films containing 30 and 40 wt% glycerol indicate the presence of ridges and valleys resulting from an extensive local deformation of the "protein matrix," which explains the large flexibility of these films as compared to those containing only 20 wt% plasticizer.