Mycoflora of South African barley and malt.
Ackermann, A.;
Journal of the American Society of Brewing Chemists Year: 1998 Vol: 56 Issue: 4 Pages: 169-176 Ref: 28 ref.
1998
บทคัดย่อ
Due to the published effects of heavy fungal contamination on malt quality, Southern Associated Maltsters determined the incidence and nature of fungal contamination in South African barley and malt. The nature and extent of fungal contamination during harvest, storage, and throughout the malting process were investigated for local crops and compared to barley and malt samples from other countries. Field fungi were determined during harvest intake on surface-sterilized barley samples collected over 6 consecutive harvest years (1991-96). Alternaria spp. were the most prevalent fungi detected during harvest intake. Cladosporium spp., Epicoccum spp., Fusarium spp. and Aspergillus spp. were the other most commonly detected genera. The results on harvest samples were in agreement with those from samples from other countries. Global climatic conditions appeared to play an important part in the contamination level by field fungi. Average fungal counts in South African barley and malt were found to be a
ppreciably lower than those found on barleys and malts from other countries. Information on the incidence of storage fungi was obtained from the fungal analysis of barley samples delivered to the maltings over 3 separate years (1993-95) and then stored for a further nine-month period. The expected decrease in the field fungi occurred with a concomitant increase in the numbers of common storage fungi (Aspergillus spp.). The effect of the malting process on fungal species and total counts was also evaluated over a period of 5 years. Fungi on the South African barley behaved similarly during the malting process to fungi from barleys from other countries. The exceptions were that Cladosporium spp. increased after kilning to the same level found in the original harvest barley and numbers of Fusarium spp. reached their maxima earlier in the process in the South African samples than in samples from other parts of the world.