The floristic composition of moulds growing on walls of food and drink processing factories

Samples were taken from heavily moulded walls at a range of food and drink processing plants. Quantitative estimates of the number of moulds, yeasts and bacteria were made and the moulds were identified. The floristic diversity of the germination areas and kilns of several maltings establishments was also investigated. The most commonly isolated organisms were Penicillium spp. although each environment appears to have its own characteristic flora with more than 50% of the total colony forming units isolated at each site being accounted for by three or fewer species. The results are discussed in relation to the microflora of mouldy walls in other environments.

Several of the fungi associated with the maltings establishments were not found at any other sites. The origin of these fungi is discussed in relation to the flora associated with grain and processing of malt.