PHYSIOLOGICAL CONSEQUENCES OF MINIMALLY PROCESSED FRUITS AND VEGETABLES

The physiological consequences of minimal processing are dire. Mechanical injury sets off a complex series of events which result in loss of quality (i.e. color, texture and flavor). Control of this wounding response is a major obstacle that must be overcome. To prolong postharvest life, respiration must be reduced while producing enough energy to maintain the “energized state”. The central roles of membranes and calcium in maintaining quality are discussed.     

STORAGE RESULTS IN LOSS OF THE ANTIGENOTOXIC PROPERTIES OF LENTINULA EDODES (SHIITAKE MUSHROOM) AND DEVELOPMENT OF IN VIVO GENOTOXICITY

In this study, we have investigated the stability of the antigenotoxic properties of dried of Lentinula edodes (Berk.) Singer mushroom powder stored at room and at − 20C. Mice were pretreated by gavage for 15 consecutive days with 0.6 mL/day of an aqueous extract of dried L. edodes powder prepared at 60C. On day 15, the mice were intraperitoneally injected with 50 mg/kg N-ethyl-N-nitrosourea (ENU); 3 h later, peripheral blood was withdrawn from the animals and used to evaluate DNA damage using the comet assay. The mice were sacrificed 24 h after the ENU treatment and the bone marrow used to measure the frequency of micronucleated polychromatic erythrocytes. The results indicated that storage at both room temperature and at − 20C significantly reduced the antigenotoxic effects of the mushroom powder. In addition, whereas freshly dried mushroom powder was nongenotoxic, storage of the powder at − 20C resulted in genotoxic activity ( P <  0.05). Taken together, our data indicate that constituents of L. edodes powder are altered during storage, resulting in both genotoxicity and a reduction in antigenotoxicity.     

Fire and explosion hazards associated with milk spray drying operations*

Recent reports in the literature indicate that incidents involving fires and explosions in the spray drying of milk products are increasing in number. While milk powder is not highly explosible, the conditions for a dust explosion, apart from the ignition source, are almost always present in certain areas of a spray drying system during its normal operation. Self-ignition of deposits is known to be possible at the high temperatures in a spray drier. At best, this can cause product degradation and discoloration and at worst it can provide the source of ignition for an explosion. This paper is an attempt to draw together recent work on fire and explosion prevention and protection for milk powders.     

Effect of Marination upon Mineral Content and Tenderness of Beef

This study compared marinated and nonmarinated beef to determine differences in semimembranosus muscle tenderness and selected mineral content. The minerals analyzed were iron, zinc, magnesium and sodium. Marination resulted in a significantly more tender muscle, as determined by shear values and trained panel evaluations. Mineral content was significantly affected by marination with substantial losses of iron, zinc, and magnesium and increased sodium. Marination would be a feasible method of enhancing tenderness of more economical cuts of beef; however, the subsequent loss and/or gain of minerals should be considered.