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The ability of dromedary skim milk to form an acid curd during a lactic acid starter fermentation was investigated. The activity of the starter in dromedary milk was characterized by a longer lag phase ( approximately 5 vs. approximately 1 h) and by an earlier decline phase. This suggests the presence of inhibiting factors. The maximum buffering capacity of dromedary milk as well as its minimum apparent viscosity were obtained at lower pH values. Similarly, its elastic modulus appeared later (pH 5.7 vs. 6.3). Because these rheological and biochemical events took place at lower pH values, dromedary skim milk seems to present a higher physical stability toward the increase of acidity. Determination of the rheological and microscopic characteristics of the dromedary milk coagulum (pH 4.4) did not reveal curd formation but indicated a fragile and heterogeneous structure. This coagulum, which is very different from that of cows' milk, seems to be made up of dispersed casein flakes.

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The aim of this study was to investigate the oxidative stress status and antioxidant enzyme activities in infertile men's semen and to determine their relationship with spermatozoa characteristics. Four groups of infertile men, normozoospermic (n=9), azoospermic (n=13), oligoasthenozoospermic (n=38), and asthenozoospermic (n=42), were tested for malonaldialdehyde (MDA) concentration and catalase (CAT) and superoxide dismutase (SOD) activities in semen using spectrophotometric methods. We found that MDA levels in semen and SOD activity in seminal plasma (SP) were significantly higher in oligoasthenozoospermic and asthenozoospermic groups compared with normozoospermic group. In contrast, the mean values of CAT activity were not significantly different in all groups. We found positive correlations between semen MDA concentration and SOD activity (P<0.01). MDA levels in sperm pellet and in SP were also positively correlated with mobility grade b (P<0.01), acrosome anomalies (P<0.01), and residual cytoplasmic droplets (P<0.05). In contrast, SOD activity in SP was negatively correlated with sperm concentration and normal morphology (P<0.05). Similarly, CAT activity in SP was negatively correlated with sperm and leukocyte concentrations (P<0.05). In conclusion, our results suggest that the evaluation of oxidative status and antioxidant defenses may be taken as an important tool for diagnosis and treatment of male infertility.

Dried egg and egg-derived proteins have a range of applications in baking, dressings, and confectionery products. Egg powder was produced under high time-temperature scales (approximately 160 degrees C), which led to many changes in egg components, resulting in different functional properties of eggs after reconstitution. In this study, moderate operating conditions were selected to dry egg white and whole egg using a pilot-scale spray dryer. Functional properties changes were evaluated with an appropriate statistical technique. Major finding supports that spray drying of egg white at moderate conditions (air inlet temperature ranged from 110 to 125 degrees C) resulted in a product that enhanced considerably the water holding capacity of produced gels. Moreover, gel prepared with the dried samples was firmer than that of the fresh samples. Drying at a moderate scale allowed not only the increasing of the foaming capacity and the stability of foam but also an increase in their emulsifying capacity and stability of the emulsions.

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