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The past 70 years have seen a dramatic change in the structure of the dairy industry, driven by socio-economic changes and by the dramatic improvements in knowledge of the physicochemical and microbiological state of milk and milk products. Production processes have been revolutionised by improvements to process hygiene and by automation. Energy efficiency will continue to have a major influence on manufacture and distribution. [ABSTRACT FROM AUTHOR]

Milk oligosaccharides ( OSs) confer unique health benefits to the neonate. Although human digestive enzymes cannot degrade these sugars, they support specific commensal microbes and act as decoys to prevent the adhesion of pathogenic micro-organisms to gastrointestinal cells. The limited availability of human milk oligosaccharides ( HMOs) impedes research into these molecules and their potential applications in functional food formulations. Recent studies show that complex OSs with fucose and N-acetyl neuraminic acid (key structural elements of HMO bioactivity) also exist in caprine milk, suggesting a potential source of bioactive milk OSs suitable as a functional food ingredient. [ABSTRACT FROM AUTHOR]

The prebiotic effect of oligosaccharides recovered and purified from caprine whey, was evaluated by in vitro fermentation under anaerobic conditions using batch cultures at 37°C with human faeces. Effects on key gut bacterial groups were monitored over 24 h by fluorescence in situ hybridization (FISH), which was used to determine a quantitative prebiotic index score. Production of short-chain fatty acids (SCFAs) as fermentation end products was analyzed by high-performance liquid chromatography (HPLC). Growth of Bifidobacterium spp was significantly higher ( P ≥ 0.05) with the purified oligosaccharides compared to the negative control. Lactic and propionic acids were the main SCFAs produced. Antimicrobial activity of the oligosaccharides was also tested, revealing no inhibition though a decrease in Staphylococcus aureus and Escherichia coli growth. These findings indicate that naturally extracted oligosaccharides from caprine whey could be used as new and valuable source of prebiotics. © 2012 International Union of Biochemistry and Molecular Biology, Inc. [ABSTRACT FROM AUTHOR]

Fluorophos and colourimetric procedures for alkaline phosphatase (ALP) testing were compared using milk with raw milk additions, purified bovine ALP additions and heat treatments. Repeatability was between 0.9% and 10.1% for Fluorophos, 3.5% and 46.1% for the Aschaffenburg and Mullen (A&M) procedure and 4.4% and 8.8% for the Scharer rapid test. Linearity ( R2) using raw milk addition was 0.96 between Fluorophos and the Scharer procedure. Between the Fluorophos and the A&M procedures, R2 values were 0.98, 0.99 and 0.98 for raw milk additions, bovine ALP additions and heat treatments respectively. Fluorophos showed greater sensitivity and was both faster and simpler to perform. [ABSTRACT FROM AUTHOR]

Halloumi cheese was produced from 11 bovine milks with fat contents of 1.61–4.04%, giving a range of 32–53% fat in dry matter (FDM) in the cheeses. Starter culture and/or microparticulated whey protein (Simplesse ® 100(E)) was also added to selected batches of milk. Hardness decreased with increasing FDM, with increase in moisture and with lower pH. On sensory evaluation, there was an increase in preference score with FDM (R 2  = 0.8). Inclusion of microparticulated whey protein may have had a fat mimetic effect, as preference scores otherwise decreased with increasing protein levels (R 2 = 0.75). [ABSTRACT FROM AUTHOR]

White-salted cheeses were prepared from ultrafiltered (UF) cows’ milk and salted to give final salt-in-moisture (SM) levels of 2.5, 3.2 and 4.0%. The cheeses were stored at 5°C and 10°C for up to 15 weeks. The microflora was dominated by lactic acid bacteria (LAB) but some mould growth was evident within 15 weeks at all SM levels and both temperatures. Levels of water-soluble nitrogen (WSN), attributed to chymosin activity, increased significantly with time, the rate being inversely proportional to the SM level and increasing with storage temperature. Similar effects were noted for trichloroacetic acid-soluble nitrogen (TCA-SN) and free amino acid (FAA) levels, both of which would also be affected by bacterial protease activity. The proteolytic activity was reflected by changes in the hardness and fracturability of the cheeses. [ABSTRACT FROM AUTHOR]

Proteolysis of Serpa cheese produced traditionally (B) and semi-industrially (C) was evaluated for the first time by determination of nitrogen content and capillary zone electrophoresis (CZE). A citrate dispersion of cheese was fractionated to determine the nitrogen in pH 4.4, trichloroacetic and phosphotungstic acid soluble fractions (pH 4.4-SN, TCA-SN and PTA-SN, respectively). The pH 4.4-SN was significantly higher for B ( P < 0.001), while TCA-SN was significantly higher for C ( P < 0.001). PTA-SN was also higher for C but at 60 days ripening no significant difference was found between B and C. Degradation of αs1 - and β-caseins evaluated by CZE was in good agreement with the maturation index (pH 4.4-SN/TN). [ABSTRACT FROM AUTHOR]

This paper reviews the use of plant extracts as vegetable coagulants for cheesemaking. It covers the plants used as sources of coagulants, with a historical overview and particular emphasis on Cynara species. The genus Cynara L., its composition, milk clotting and proteolytic enzymes (cardosins) and their specificity towards peptide linkages are also described. Cheeses produced in the Iberian Peninsula using Cynara L. as coagulant are documented. Cynara L. is still the most used vegetable coagulant in cheesemaking, and also the most investigated. However, much work remains to be done to understand its action during cheese maturation and further characterization. [ABSTRACT FROM AUTHOR]

The effects of the starter culture biomass material and its exopolysaccharides (EPS) on the structure of bovine and caprine acid gels were investigated. Inactivated cell material and/or extracellular polysaccharide, which had been separated from yogurt starter cultures, were added to both types of milk. The milk systems were acidified using glucono-δ-lactone (GDL) and the gelation processes were monitored using dynamic (oscillatory) rheological testing. The addition of cell material had no effect on the bovine acid gel, whereas the addition of polysaccharide produced a weaker gel structure. The addition of cell material (> 5 × 108 cells/mL) and polysaccharide (0.35% w/v) weakened the caprine acid gel system. The treated gels were some three to eight times weaker than the untreated samples, suggesting that the starter culture metabolites and especially the EPS may act by interfering with the gel structures, particularly in the cases of milk systems such as caprine yogurt or low protein content bovine yogurt. [ABSTRACT FROM AUTHOR]

The article presents an obituary for Doctor Richard Robinson.

The article reports that the Society of Dairy Technology (SDT) Gold Medal was conferred on Professor Patrick Fanahan Fox.

The article presents details of the proceedings of a major international symposium held in Cork, Ireland on October 22, 2003, and whose information was published in the May 2004 issue of "International Journal of Dairy Technology." The symposium marked the 40th year since the publication of P.F. Fox's, professor of dairy chemistry and technology, first research paper. At this meeting, a number of P.F. Fox's former postgraduate students and fellow researchers provided reviews of the progress in the fields of dairy chemistry and technology to which Fox contributed.

This study demonstrated that both chymosin and salt-in-moisture (SM) were important factors for proteolysis in the manufacture of ultrafiltrated white-salted cheese, with significant effects on water-soluble nitrogen and nitrogen soluble in trichloroacetic acid. In contrast, the levels of free amino acids were not significantly affected by chymosin and salt treatments. The cheeses made, using high levels of chymosin with low SM had lower levels of residual alpha(S1)- and beta-casein at the end of ripening. On texture profile analysis, the hardness and fracturability of the cheeses significantly increased with SM and decreased during ripening. Increases in chymosin significantly contributed to the overall weakening of the structure throughout ripening. Bitter flavour was detected after 12 weeks in the cheese made with the higher chymosin level and lower SM, which could be the result of accumulation of gamma-casein fractions. The sensory data indicated that the hedonic responses for low chymosin with low SM cheeses were good and acceptable in flavour, which may be due to the moderate levels of proteolysis products.