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Balanites aegyptiaca Del. kernels were chemically, physically and morphologically characterized. Crude oil (49.0%) and crude protein (32.4%) were the two major constituents of the kernels. Phytic acid content was relatively high compared to other legumes. In contrast, antitryptic activities of the kernel flours were very low. Sapogenin contents of the full fat, defatted and testa flours were 1.5, 2.7 and 3.0%, respectively. The hardness of the kernel was found to be about 10.4 x 10(5) N/m2, which was somewhat high. The morphological structure of the kernel using a scanning electron microscope revealed that the protein matrix was embedded in a lake of oil droplets. Oil recovery, as a function of pressing time, pressure, temperature and particle size was investigated. With increasing temperature up to 70 degrees C at 400 bar, for 120 min, an oil recovery of 79.4% was obtained. Using an expeller at 115 degrees C, about 85% of the kernel oil was recovered. The reduction of particle size had a negative effect on oil recovery under the same conditions. The fatty acid composition was not affected by the pressing temperature up to 115 degrees C. The total amount of the unsaturated fatty acids was found to be up to 74.8% (50 degrees C) and 75.1% (115 degrees C) of the total fatty acids content.

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Confocal scanning laser microscopy (CSLM) is a recently developed light microscopy technique which permits observation of selected levels within thick samples. CSLM improves the resolution along the viewing axis and permits optical sectioning of the sample. Sample preparation is not time consuming and changes the original structure of the specimen only minimally. In this way structures involved in kinetic processes of food materials exposed to external stress situations can be visualized. In this review the contributions of CSLM to improving the understanding of various processes in different fields of food science are discussed. The fundamentals of the operations required are considered, including a discussion of common laser sources and different kinds of fluorescent dyes. Attention is paid to the peculiarities of sample preparation, as well as to the possibilities of image processing in order to improve and analyze the images collected. The quantitative analysis of plant organizations and cellular structures in plant material by CSLM is reported as well as the use of CSLM to image the structure of emulsions of different complexity and to locate microorganisms in a wide range of food products.

Minimized experiments with Confocal Scanning Laser Microscopy were used to describe mass transfer of isolated carrot protoplasts from at the usual conditions of the Osmotic Treatments (OT). Carrot protoplasts during OT with 30, 40 and 50% sucrose solutions were monitored. The ratio of cellular volume before and after OT with 30, 40 and 50% sucrose solutions was 0.86 ± 0.12, 0.41 ± 0.04 and 0.17 ± 0.02, respectively. Trans-membrane water flux was determined from cellular shrinkage, and the coefficient for water membrane permeability was (5.2 ± 0.9) 10 -6 mol 2 /Jm 2 s. To describe water transport in protoplasts at transient conditions, the diffusional approach was used. The effective water diffusivity during OT with 50% sucrose solutions was in the (0.8-1.8) 10 -12 m 2 /s range.