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The Belgian diary farms are studied in order to understand the presence, sources, and nature of potentially highly heat-resistant spores in raw milk in general and the presence of Bacillus sporothermodurans spores in particular. Assessment and characterization of these spores are very important to allow the dairy or food industry to deal with newly arising microbiological problems.

Research has been conducted on the lactic acid bacteria used for fermented food production. The milk-clearing procedure optimized for the flow cytometry analysis of bacteria in milk and bacteria's viability in dairy starters and probiotic products have been investigated and are reported.

A new study investigates the ability of bifidobacteria and lactic acid bacteria to grow when exposed to clover honey, sucrose and fructose.

Research on Lactococcus lactis provides information useful for developing strains that can efficiently release relevant enzymes and proteins outside cells without known export and secretion signals, a significant fermentation innovation for the dairy industry. The research involved controlled expression of integrated phage holin and lysin cassettes.

The isolation and successful relysogenization of a prophage-cured Propionibacterium freudenreichii derivative confirmed lysogeny in P. freudenreichii, a dairy bacteria used in Swiss cheese ripening. The process involved treating strains with ultraviolet irradiation or low mitomycin C concentrations.

Research was conducted to detect dairy propionibacteria in enviromental samples using PCR assays with primers targeted to the genes encoding 16S rRNA. Propionibacterium thoenii specific oligonucleotide PT3 was chosen after partial resequencing. The possibility to selectively detect P acnes with primers PT2-PB2 could allow its distinction from the other cutaneous propionibacteria and should be further investigated.

A study has revealed that the low-water activity and high-salt-concentration characteristic of cheese imparts lactocepin III characteristics to lactocepin I. The effects of these parameters on the specificity of lactocepin III on the stability of lactocepin I and III were accurately determined. Findings indicate that proteolysis can elucidate certain key factors in cheese flavor development, since proteolytic enzymes are instrumental in the ripening process of most cheeses.

Several genetic constructions were designed to examine the influence of abiA gene dosage variation on bacteriophage resistance in Lactococcus lactis. Phage DNA replication is blocked by an absortive phage infection mechanism encoded by the abiA gene. Phage resistance levels are greatly affected by modifying the gene dosage or expression level of abiA.

Bovine plasmin activity was studied on Cheddar cheese ripening to evaluate its effect on the improvement of sensory quality in cheese. Plasmin activity was noted to have increased with proteolysis and was found to accelerate ripening and to improve the quality of cheese after three and six months ripening. Cheeses with a three-fold increase in plasmin activity were noted to have the most improved flavor but had showed that activity had a minimal effect on the texture.

Production of fresh farm milk in Namibia is low due to the arid climate that prevails in the country, low pasture availability and a high milk demand. This scenario has forced Namibia to import dairy products to meet its needs from neighbouring South Africa, South America and Europe. Namibia imports different brands of fresh full cream milk including Parmalat, Clover, Super milk to add on to its own brands such as Namdairies, UNAM milk and others from private and commercial farms in bulk or in plastic sachets and bottles. Generally, milk quality is determined by its safety, shelf life and nutrition. The presence of different brands of milk makes it difficult for milk consumers in Namibia to choose the brand they would prefer including assessing their value for money. The aim of the project was to determine the quality of full cream milk brands marketed in Namibia by assessing their proximate composition, titratable acidity, pH, protein stability, total plate count and Coliform bacteria as indicator bacteria for the presence of pathogens, using standard dairy procedures and AOAC methods. The results of the study indicated that all imported brands of pasteurised full cream milk in Namibia were not significantly different from each other and were safe and stable, and nutritionally of good quality. They were practically the same in composition and bacteriological quality. Butterfat ranged from 3.4 to 3.7%, density from 1.029 to 1.032g/[cm.sup.3], total solids from 12.3 to 13.0%, solids-not-fat from 8.6 to 9.7%, moisture content from 87.10 to 87.70%, acidity as lactic acid from 0.15 to 0.17% and pH from 6.4 to 6.7. The total plate count (TPC) ranged from 0 to 40 cfu/cm and there were no Coliform bacteria found in all the brands. The local products were not statistically different in composition from imported brands, with fat ranging from 3.3 to 3.7%, density from 1.029-1.032g/cm3, TS from 12.3-12.9% and SNF from 8.6-9.4% though they were not standardized but heat treated. The total aerobic counts and Coliforms were the same as those of imported milk brands. The statistical analysis showed that there were no significant differences at p Key words: Milk, Composition, Bacteriology, Safety, Quality, INTRODUCTION The human population in Namibia has been increasing over the years and the demand for food is also increasing proportionally, especially for milk products. Milk products provide nutrients that [...]

Results show that Listeria Monocytogenes is detected in 1.0% of the 294 farm bulk tanks tested, whereas the contamination level is 19.6% in the milk from the silo receiving tanks at a Swedish dairy plant. Molecular analysis indicates that out of 65 isolates of L. monocytogenes, 16 different clonal types are identified, while the dairy silo milk showed five clonal types.