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In the production of some traditional cheeses from vegetable rennet, raw extracts of Cynara cardunculus flowers are used as the coagulant. During the preparation of this rennet, there are many factors that can influence its coagulation activity. We studied the flowers of Cynara cardunculus var. altilis to evaluate the effects of some of these factors: ripening stage of the flower at harvest, type of drying, part of the flower subjected to drying, toasting of the pistils, and maceration time of the pistils. The results show that it is possible to improve the coagulation activity of the traditional preparation of Cynara cardunculus flowers through some practices such as the rapid drying of the flowers/pistils at a controlled temperature, the toasting treatment of the pistils carried out after the slow drying of the flowers, and the extension of the extraction time to 24 h.

The oxidative stability of milk and dairy products is a very interesting topic for the dairy industry due to the growing demand for foods containing bioactive compounds with positive health effects. The aim was to evaluate the oxidative stability of milk intended for cheese production. The effect of storage time, heat pre-treatment, and milk pasteurization temperature on the characteristics of milk and cheese was investigated. The cheese samples were produced with pasteurized milk at both 72 and 77 °C for a time of 15 s using three types of milk: raw fresh milk processed within 48 h of milking, raw stored milk processed within 96 h, and thermized milk that was heat-treated upon arrival at the dairy and processed within 96 h of milking. In total, three repetitions were carried out for each type of milk and pasteurization. Samples of milk before and after pasteurization and cheese at 14 days of storage were analyzed. Antioxidant activity decreased from starting milk to milk after pasteurization to final cheese. The longer storage time of the milk had significant effects on the antioxidant stability of the cheese (64.95 vs. 59.05% of antioxidant activity). Thermization of the milk further reduced the stability of the cheese (54.05% of antioxidant activity). The greater antioxidant stability of fresh milk and cheeses produced with fresh milk is the first result that encourages the production of cheese from a milk that best preserves its original characteristics.

Milk and dairy products can have variable contents of antioxidant compounds that contribute to counteract the oxidation of lipids and proteins during processing and storage. The content of active antioxidant compounds is closely linked to their protection by oxidation. Freezing is one of the factors that can reduce antioxidant activity. Freezing of milk or curd is frequently used in case of the seasonality of milk production and/or seasonal increased demand for some products. In this paper, the effect of using frozen curd on the oxidative stability of buffalo Mozzarella cheese was evaluated. Samples of buffalo Mozzarella with different frozen curd content (0%, 5%, 20%, and 50%) were produced and analyzed at one and nine days. Mozzarella cheese with higher frozen curd content had a significant increase in redox potential parallel to the decrease in antioxidant activity, showing less protection from oxidation. Lipid and protein oxidation, expressed respectively by malondialdehyde and carbonyl content, increased significantly with increasing frozen curd. At nine days, carbonyls significantly increased while malondialdehyde content did not vary, showing that during storage, fat was more protected from oxidation than protein. The average carbonyl levels were comparable to those of some cooked cheeses, and the malondialdehyde levels were even lower. The results of this study stimulate the investigation of new strategies to decrease the oxidative damage in cheeses produced in the presence of factors decreasing oxidative stability.

The trial was carried out using 14 multiparous buffaloes divided into two groups according to yield in the previous lactation (2653 vs. 2625 kg), number of lactations (4.8 vs. 4.1), live weight (670.6 vs. 657.1 kg), days post-calving (21.6 vs. 23.6 days) and average yield at the on-set of the trial (11.18 vs. 10.90 kg/day). The effects of both feed intake and the quanti–qualitative parameters of the milk yield were evaluated following the ad libitum administration of two diets containing two different forage/concentrate ratios, diet 1 = 48 : 52 (0.94 Milk FU/kg DM, 158.3 g/kg DM of crude protein); diet 2 = 55 : 45 (0.85 Milk FU/kg DM, 144.4 g/kg DM of crude protein). The trial lasted for 114 days, on average from day 23 to 137 of lactation. The dry matter intake for diet 1 was 16.37 kg/day, for diet 2 it was 16.53 kg/day. No significant differences were found with live weight of the animals; however, the buffaloes in group 1 showed gains of 35.0 kg compared to 54.2 kg of those in group 2. A significant difference ( P r = 18.35 min, K 20 = 3.88 min, A 30 = 47.00 mm), than group 1.

The aims of this study were to evaluate the gastric electrical activity and gastric emptying in preterm and term newborns and to assess the development of gastric motility by comparing newborns of different gestational ages. The cutaneous electrogastrography and the ultrasonographic study of the gastric emptying were performed before and after milk formula in three groups of infants: 12 preterm newborns with a gestational age of 28-32 weeks, 11 preterm newborns with a gestational age of 32-36 weeks, and 10 full-term newborns with a gestational age of 36-40 weeks. All recording sessions were performed 1 week after infants had reached full enteral feeding. The percentage of normal slow waves was similar in the three groups but it was not predominant compared to tachygastria in the earliest premature infants (59.3% (12.7-92.3) vs. 29.6% (3.7-78.8); P < 0.05). In addition, a progressive increase in the normal slow wave percentage (59.3% (17.4-87.4), 60.9% (38.1-89.7), 77.8% (66.4-84.8); P < 0.05) was observed as gestation advanced. As regards gastric emptying parameters, the antral area was greater and T(1/2) was longer in the preterm newborns of 28-32 weeks than preterm newborns of 32-36 weeks and full-term newborns (fasting antral area: 0.96 cm2 (0.6-1.5), 0.63 cm2 (0.4-1.2), 0.55 cm2 (0.1-0.9) respectively, P < 0.05; T(1/2): 83.4 min (76.0-108.5), 70 min (57.5-89.5) and 71.8 min (54.9-81.2), respectively P < 0.05). The comparisons of gastric emptying curves made among the three groups showed a reduced antral dilatation in preterm newborns of 28-32 weeks compared to full-term newborns at 30 and 60 min after a meal. In conclusion, although enteral feeding is important for the development process of gastrointestinal motility, gastric electrical activity and gastric emptying show an intrinsic maturation depending on the gestational age.