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Limonin is the major naval orange juice bitter principle and to better understand and optimize the sorption of limonin, a sorption and plasticizer migration study was carried out. Results showed that the best debittering was obtained by using low molecular weight poly plasticized with dioctyl adipate and that the debittering efficiency was greater than that obtained with current polystyrene divinylbenzene resin beads.

Threshold levels of 2-nonanone vapor required to restrict Penicillium expansum and Botrytis cinerea growth on Potato Dextrose Agar (PDA) and apple slices, were determined. 2-nonanone was an effective antifungal agent but led to peel discoloration of apple slices, although this may not be an issue in commercially processed apples, which are usually cored, peeled and sliced.

Biodegradable and edible films for food packaging are prepared from wheat protein whose oxygen permeability is comparable to commercial nylon. The film's elongation at break and tensile stress at break are lower than the commercial nylon and it is softer than commercial nylon films. The films have homogeneous appearance and glossy surface, and are translucent. The tensile strength of the films having cystine is higher than that of films without cysteine. A method for extraction of protein from wheat and film casting is developed.

Gas chromatography is best suited for determining partition coefficient (K) of organic compounds in water/polystyrene systems, and for the systems with high K values. Gel permeation chromatography, which is independent of solvent extraction, is the best technique to measure the sorbate concentrations in the polymer phase. Dynamic thermal stripping-thermal desorption technique also gives good results in measuring the sorbate concentrations in the polymer phase. The K values for toluene, d-limonene, and ethyl acetate are found to be 800, 5100 and 1.9, respectively.

Presents a study in which a flow-through vapor exposure system was developed to evaluate the effects of 2-nonanone vapor on the decay of apple slices inoculated with Penicillium expansum Link and Botrytis cinerea Pers. Conditions under which the study was conducted; Description of the various reactions that occured.

The sorption of selected polychlorinated biphenyl (PCB) congeners (from tri to deca chlorinated) by three food-packaging plastic films [polyethylene, polyvinyl chloride (PVC), and polystyrene] from an aqueous solution was investigated. From the data generated, PCB uptake, partition, and diffusion coefficients were calculated for the various films. Polyethylene exhibited the highest PCB uptake, diffusion, and partition coefficients when compared to the other materials. Although PVC indicated larger sorption diffusion and partition coefficients for the lower chlorinated congeners than polystyrene, a reversal of this trend was observed for the higher congeners. For polyethylene and PVC, the PCB uptake decreased as the chlorine numbers in the congeners increased, confirming the correlation between increasing chlorination and increasing cohesive density within the PCB molecules. For polystyrene, the uptake decreased from tri to penta congeners, but showed an increase for the hexa, and then a decreased uptake until the deca chlorination. A comparison of the molecular sizes of the PCB congeners showed that the partition (Ke) and sorption diffusion (Ds) coefficients generally decreased with their increasing molar volumes. The resulting Ke values were used to determine the extent of sorption because these values indicate the affinity of PCBs for the plastic films. Results from this study can be of practical importance for cases of product quality related to the transfer of contaminants from the product to the packaging materials.