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Three upflow anaerobic sludge blankets (UASBs) were evaluated for the treatment of winery wastewater: the first was seeded with granular sludge enriched with Enterobacter sakazakii and reached a 90% COD removal within 17 d at hydraulic retention time of 24 h; the second was seeded with brewery granules and achieved 85% COD removal within 50 d, the third was seeded with just sludge and showed the typical problems encountered with conventional sludge seeding and had continuously to be re-seeded. A PCR-based technique was developed for the rapid detection of E. sakazakii in the granular sludge.

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Aims:  To determine the effect of UV radiation on the viability of two strains of Mycobacterium avium ssp. paratuberculosis (Map) inoculated into milk. Methods and Results:  Mycobacterium avium ssp. paratuberculosis in a ultra heat treated milk matrix was subjected to increasing doses of UV‐C radiation from 0 to 1836 mJ ml−1 using a pilot‐scale UV reactor (20 l capacity). Survival of Map was monitored by culture on Herrold’s egg yolk medium, Middlebrook 7H10 medium and the FASTPlaqueTB™ phage assay. Differences in sensitivity to UV treatment were observed between strains, however, at 1000 mJ ml−1 a Map kill rate of 0·1–0·6 log10 was achieved regardless of strain used or method employed to enumerate Map. Although the inactivation trend was similar on the culture and phage assay, the former gave a consistently higher viable count. Conclusions:  The use of UV radiation alone does not represent an alternative to current pasteurization regimes for a large reduction in viable Map in milk. Significance and Impact of the Study:  To the authors’ knowledge the work here represents the first pilot‐scale UV treatment process used to assess UV efficacy to inactivate Map in milk. The results are similar to those obtained with a laboratory‐scale process indicating the difficulties associated with UV treatment of an opaque liquid and the recalcitrance of Map towards inimical treatments.

The effective operation of the anaerobic digestion process in an upflow anaerobic sludge blanket (UASB) bioreactor is dependent on the microbial composition of the UASB granules. The granules contain a consortium of bacteria, with a specific metabolic function for each group, contributing to the overall efficiency and stability of the bioreactor. The aim of this study was to fingerprint and identify the bacteria present in four different types of South African UASB granules that are used to treat winery, brewery, distillery and peach-lye canning wastewaters. This was done by combining conventional microbiological platings with PCR-based denaturing gradient gel electrophoresis (DGGE) and DNA sequence analysis. Each granule type showed distinct PCR-based DGGE fingerprints with unique bands, while other bands were found to be present in all the granules, regardless of the wastewater being treated. Sixty-eight different bacteria (40 pure isolates and 28 clones) were partially sequenced and identified from the winery, brewery, distillery and peach-lye canning granules. Thirty-five percent of the identified bacteria represented the unculturable bacteria and 65% represented the culturable bacteria, which included members of the following genera: