AGFD 69 |
| Previously we found that edible films containing low levels of plant essential oils (oregano, cinnamon, and lemongrass) and their major constituents (carvacrol, cinnamaldehyde, and citral) induced rapid reduction of pathogenic bacteria such as E. coli O157:H7 (J. Agric. Food Chem. 54, 9262, 2006; J. Food Eng. 81, 634, 2007). Because edible films made from fruits and vegetables have the potential to protect food against contamination by pathogenic bacteria, we evaluated the stability of carvacrol added to tomato/pectin films during their preparation and storage. A material balance showed that the concentration of carvacrol (0.15% w/w) added to the puree suspension should increase to 0.77% (w/w) in the final dried product, assuming carvacrol evaporation loss is negligible during homogenization and drying of the films at room temperature. Surprisingly, HPLC analysis indicated that ~ 83% of the original carvacrol added to the suspension was lost during the production (casting) of the films. By contrast, HPLC analysis of film extracts following storage in sealed plastic bags at 5 °C or 25 °C revealed that carvacrol levels in the films remained unchanged over the period of seven weeks. The cited observations facilitate relating compositional and physico-chemical properties of tomato/pectin puree films containing volatile antimicrobials to their use in foods. Supported by NRI-CSREES-USDA grant 2006-35201-17409. |
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General Papers
8:00 AM-1:00 PM, Tuesday, August 21, 2007 BCEC -- 255, Oral
Division of Agricultural & Food Chemistry |