Impact of Milk Storage and Heat Treatments on In Vitro Protein Digestibility of Soft Cheese.

Cheese is an important source of protein in the human diet, and its digestibility depends on its macro and microstructure. This study investigated the effect of milk heat pre-treatment and pasteurization level on the protein digestibility of produced cheese. An in vitro digestion method was used considering cheeses after 4 and 21 days of storage. The peptide profile and amino acids (AAs) released in digestion were analyzed to evaluate the level of protein degradation following in vitro digestion. The results showed the presence of shorter peptides in the digested cheese from pre-treated milk and 4-day ripening while this trend was not observed after 21 days of storage, showing the effect of storage period. A significantly higher content of AAs was found in digested cheese produced from milk subjected to a higher temperature of pasteurization, and there was a significant increase in total AA content in the cheese after 21 days of storage, confirming the positive effect of ripening on protein digestibility. From these results emerges the importance of the management of heat treatments on the digestion of proteins in soft cheese.

Chemical Characteristics and Oxidative Stability of Buffalo Mozzarella Cheese Produced with Fresh and Frozen Curd.

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.

Increasing the Sustainability of Maize Grain Production by Using Arbuscular Mycorrhizal Fungi Does Not Affect the Rumen of Dairy Cattle (Bos taurus) and Buffalo (Bubalus bubalis).

New approaches are needed to improve the sustainability of feed production and utilization by ruminants. Promising approaches include increased use of buffaloes for more sustainable milk production, and arbuscular mycorrhizal fungi (AMF) to reduce crop production input needs. However, studies assessing the effect of crops grown in the presence of AMF on rumen microbial utilization are limited. Based on current knowledge, we hypothesized that maize grain grown on AMF-inoculated soil affected ruminal fermentation and microbiota, and that this effect differed between buffalo and cattle. A dietary cross-over study (four weeks per diet) was conducted using rumen-cannulated cattle (n = 5) and buffalo (n = 6) to assess the effect of maize grain (3.9% (w/v) of diet) grown on soil with or without AMF (15 kg/ha) on ruminal fermentation and microbiota. Production of maize on AMF-treated soil did not affect any of the assessed ruminal fermentation parameters, microbial concentrations, or prokaryotic community composition (using prokaryotic 16S rRNA gene sequence analysis). In contrast, host type had numerous effects. Protozoal counts, lactate, total VFA and isobutyrate, were significantly higher in buffaloes compared to cattle. Conversely, butyrate was significantly lower in buffaloes than in cattle. Host type explained 9.3% of the total variation in prokaryotic community composition, and relative abundance of nine amplicon sequence variants significantly differed between host types. These findings indicate that AMF treatment of maize crops has no detrimental impact on the value of the resulting maize grains as a ruminant feed, and provides additional insight into rumen-based differences between cattle and buffalo.

Diagnostic accuracy and predictive value of extended autoantibody profile in systemic sclerosis.

Systemic sclerosis (SSc) is a heterogeneous autoimmune disorder characterized by microvascular injury, fibrosis of the skin and other organs, and presence of antinuclear autoantibodies (ANA) with a prevalence varying from 80 to 98%. The ANA classically detected in SSc include anti-centromere (ACA) and anti-topoisomerase I (ATA), which are positive in 50-60% of the patients. Even if other autoantibodies, such as anti-fibrillarin (AFA), anti-RNA polymerase III (RNAP III), anti-PMScl, anti-Th/To, and anti-hUF/NOR-90, are almost specific for SSc, until recently they were not routinely looked for, since the techniques for their identification were not suitable for routine use. In recent years, the advances in the knowledge of the biochemistry and of the immunoreactive sites of the autoantigens led to the development of new immunoassays using recombinant proteins as autoantigens. We evaluated a new multiplex line immunoblot assay (LIA) for the simultaneous detection of 13 different SSc-associated autoantibodies, in a cohort of 210 SSc Italian patients. The sensitivity and the specificity of this assay were as follows: 30.5% and 97.3% for ACA (anti-CENP-B), 29.5% and 96% for ACA (anti-CENP-A), 20% and 99.3% for ATA, 5.7% and 99.3% for anti-RNAP III (RP-155), 5.2% and 100% for anti-RNP III (RP-11), 6.7% and 98% for anti-PMScl (PMScl-100), 10.9% and 93.3% for anti-PMScl (PMscl-75), 3.3% and 98.7% for anti-Th/To, 0.48% and 100% for AFA, 4.8% and 96.7% for anti-hUF/NOR-90, 4.7% and 96% for anti-Ku, 0.95% and 100% for anti-Platelet-Derived Growth Factor Receptor, and 18.1% and 50% for anti-Ro-52, respectively. These results, which are similar to those obtained in other studies using traditional techniques, show that the LIA assay can be considered a more rapid and a more practical method than immunoprecipitation assays for studying SSc-related antibodies in the diagnostic work-up of SSc patients.