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Changes in distribution patterns and demand for increased food quality have resulted in a desire to improve the shelf life of nonsterile dairy products. Refrigerated shelf life extension typically requires, at a minimum, reductions in the growth rate of spoilage microorganisms and subsequent product deterioration. Reducing initial bacterial loads, increasing pasteurization regimes, and reducing postprocessing contamination have all been employed with measured success. The use of antimicrobial additives has been discouraged primarily due to labeling requirements and perceived toxicity risks. Carbon dioxide (CO2) is a naturally occurring milk component and inhibitory toward select dairy spoilage microorganisms; however, the precise mechanism is not fully understood. CO2 addition through modified atmosphere packaging or direct injection as a cost-effective shelf life extension strategy is used commercially worldwide for some dairy products and is being considered for others as well. New CO2 technologies are being developed for improvements in the shelf life, quality, and yield of a diversity of dairy products, including raw and pasteurized milk, cheeses, cottage cheese, yogurt, and fermented dairy beverages. Here we present a comprehensive review of past and present research related to quality improvement of such dairy products using CO2.

Two-dimensional protein electrophoresis (2-DE) has undergone many technical improvements in the past 30 years, resulting in an analytical method that is unparalleled in the resolution of complex protein mixtures and capable of quantifying changes in protein expression from a wide variety of tissues and samples. The technique has been applied in many studies of neurologic disease to identify changes in spot patterns that correlate with disease. The true power of the technique emerges when it is coupled to state-of-the-art methods in mass spectrometry, which enable identification of the protein or proteins contained within a spot of interest on a 2-DE map. Investigators have successfully applied the technique to gain improved understanding of neurologic disease mechanisms in humans and in animal models and to discover biomarkers that are useful in the clinical setting. An important extension to these efforts that has not been realized thus far is the desire to profile changes in protein expression that result from therapy to help relate disease-modifying effects at the molecular level with clinical outcomes. Here we review the major advances in 2-DE methods and discuss specific examples of its application in the study of neurologic diseases.

Inhibition of bacterial growth by dissolved carbon dioxide (CO2) has been well established in many foods including dairy foods. However, the effects of dissolved CO2 on specific growth parameters such as length of lag phase, time to maximum growth rate, and numbers of organisms at the stationary phase have not been quantified for organisms of concern in milk. The effect of dissolved CO2 concentrations of 0.6 to 61.4 mM on specific bacterial growth parameters in raw or single organism inoculated sterile milk was determined at 15 degrees C by conductance. Commingled raw or sterile milks were amended to a final concentration of 0.5 mg/ml each of urea and arginine HCl. Sterile milks were inoculated singly with one of six different microorganisms to a final concentration of approximately 10(2) to 10(3) cfu/ml; raw milk was adjusted to a final indigenous bacterial population of approximately 10(3) cfu/ml. Conductivity of the milk was recorded every 60 s over 4 to 5 d in a circulating apparatus at 15 degrees C. Conductivity values were fit to Gompertz equations and growth parameters calculated. Conductance correlated with plate counts and was satisfactory for monitoring microbial growth. Data fit the Gompertz equation with high correlation (R2 = 0.96 to 1.00). In all cases, dissolved CO2 significantly inhibited growth of raw milk bacteria, influencing lag, exponential, and stationary growth phases as well as all tested monocultures.

Les lipides des graines entieres de soja sont resistantes a l'oxydation a part certains lipides polaires. Les graines broyees et l'huile sont plus sensibles a l'oxydation

In view of their possible role in oxidative deterioration of seeds and pollen, organic free radicals were measured by electron spin resonance in embryonic axes and cotyledons of soybean [Glycine max (L.) Merr], embryo and endosperm fractions of corn [Zea mays L.] and pollen of cattail [Typha latifolia L.]. A pronounced decline in the radical signal ensued when hydration increased above about 7% (wet weight basis) in both the seed materials and in pollen. Moderate hydration of the soybean axis followed by drying led to a small decrease in organic free radicals compared to untreated material, especially if the desiccation step was performed under nitrogen. In a comparison of soybeans of various ages under normal storage, organic free radical levels in the axis showed little or no increase with age. In marked contrast, over 5 days of accelerated aging at 40°C and near-saturating humidity, organic radical levels approximately doubled in the axis. This pronounced increase in free radical content was not associated with a decrease in the proportion of polyunsaturated fatty acids. The data suggest that hydration of seed and pollen causes a release of free radicals from the trapped state.