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This paper investigates improvement possibilities in the cleaning operations undertaken at an industrial brewery. Experiments were performed on a bench scale cleaning rig which was designed to simulate ‘real life’ cleaning conditions of a clean-in-place (CIP) set in the brewery. The rig was used to clean consistently fouled coupons using difficult soils from the brewery. The objective of the experiments was to determine the reduction in effective cleaning performance with varied levels of Na2CO3 in the detergent from NaOH degradation and the maximum level that may be present before cleaning quality is impacted. The shear force of the cleaning fluid across the surface of the coupon was also varied to determine the impact on cleaning performance. Data collected from these offline measurements has been used to predict the end point of the detergent usage based on cost optimisation within the empirically determined limits. The results show that the NaOH detergent usage can be extended while achieving the same time to clean without impacting the cleaning quality and preventing premature disposal. This will provide an increased confidence level when cleaning fermenters with NaOH. It will also reduce cleaning costs and benefit the environment by reducing chemical effluent and minimising water consumption.

Malts which conform to most commercial specifications can be prepared from Galant barley, which is low in anthocyanogens. However, the malting performance of this variety is only medium and considerable care is required during kilning in order to avoid excessive colour development. Beers brewed from Galant malt have greatly improved chill haze stability, although flavour stability is not significantly affected. Fining and filtration studies on rough beer and forcing tests for the development of non-biological haze in finished beer indicate that the use of Galant malt greatly reduces the extent of precipitation of particulate matter during brewing, conditioning and subsequent storage. This can result in considerable savings in the use of finings, and in longer filter runs since levels of addition of body feed can be reduced. It is suggested that the use of low anthocyanogen malts could, with some beers, reduce the necessity for chilling prior to and during filtration.

Effective bed voidage is a reliable characteristic of filter-aids, both kieselguhrs and perlites. When combined with the evidence of electronmicrographs, it gives excellent correlation between filtration theory and practice. Effective bed voidage is a more reliable characteristic than permeability when comparing different filter materials. A typical effective bed voidage for a bodyfeed grade filter-aid is 37%. This is considerably less than the total voidage, which is a most inappropriate measurement for the assessment of filter-aids, despite it being generally quoted.