Suitability of plastic films in standard configurations to maintain modified atmospheres was evaluated for common fruits and vegetables. Most films did not result in optimal O2 and CO2 atmospheres, especially when produce had high respiration. Produce with low and medium respiration could be matched with films considering Oa permeability requirements alone. MA packaging systems designed to produce optimal oxygen at suitable temperatures could have complications from transient temperature increases during storage and/or transportation. Respiration rates of fruits and vegetables increase more with temperature than do gas permeabilities of films. Higher than optimum temperatures could cause anoxia and seriously damage produce. More permeable gas pathways and temperature compensation to equalize Qra values are needed for MA packaging systems to timction effectively.

Rapid improvements in the understanding of the nutritional requirements of both infants and adults has led to new developments in the modification of fats and oils. Specific targets include the improvement in growth and development of infants, treatment of disease in adults, and disease prevention. Efforts have been focussed on the production of structured lipids using medium-chain acids and long-chain polyunsaturated fatty acids (PUFAs), as well as the concentration of long-chain PUFAs from new and existing sources. Short- and medium-chain fatty acids are metabolized differently than long-chain fatty acids and have been used as a source of rapid energy for preterm infants and patients with fat malabsorption-related diseases. Long-chain PUFAs, specifically docosahexaenoic acid and arachidonic acid, are important both in the growth and development of infants, while n-3 PUFAs have been associated with reduced risk of cardiovascular disease in adults. Based on the requirements for individual fat components by different segments of the population, including infants, adults, and patients, ideal fats can be formulated to meet their needs. By using specific novel fat sources and lipid modification techniques, the concentrations of medium-chain, long-chain saturated, and long-chain polyunsaturated fatty acids as well as cholesterol can be varied to meet the individual needs of each of these groups. While genetic modification of oilseeds and other novel sources of specific lipid components are still being developed, chemical and lipase-catalyzed interesterification reactions have moved to the forefront of lipid modification technology. Fractionation of fats and oils to provide fractions with different nutritional properties has potential, but little work has been performed on the nutritional applications of this method. The choice of suitable lipid modification technologies will depend on the target lipid structure, production costs, and consumer demand. A combination of some or all of the present lipid modification techniques may be required for this purpose.

Small diameter alginate beads (microspheres) were formed via internal gelation of alginate solution emulsified within vegetable oil. Gelation was initiated by addition of an oil-soluble acid thereby reducing the pH of the alginate solution and releasing soluble Ca2+ from the citrate complex. Smooth, spherical, micron-sized beads were formed. The mean diameter ranged from 200 to 1000 microns, controlled by the reactor impeller design and rotational speed. The technique has potential for large-scale and continuous applications in immobilization.

Milk fat was sequentially crystallized from ethyl acetate into three major componentssa high melting fraction (HMF), a middle melting fraction (MMF), and a low melting fraction (LMF)sin 12%, 34%, and 54% (w/w) yields, respectively. The phase behavior of mixtures of HMF, MMF, and LMF was studied using solid fat content vs temperature data. Binary and ternary phase diagrams of mixtures of the three components were constructed. Binary HMF-MMF mixtures displayed monotectic solution behavior, forming a solid solution, whereas both LMF-HMF and LMF-MMF binaries formed partial solid solutions. The LMF fraction interacted more strongly with MMF than with HMF. Ternary phase diagrams showed the complex interaction between the three components simultaneously. On average, monotectic solution behavior was observed in mixtures of the three fractions at temperatures between 0 and 15 °C and above 30 °C. A eutectic was observed between a MMF-HMF solid solution and LMF at 0 °C. At temperatures corresponding to the melting range of MMF (15 °C < T < 30 °C), complex solution behavior was observed, with strong interactions between MMF and LMF.

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