Microbiological air quality of processing areas in a dairy plant as evaluated by the sedimentation technique and a one-stage air sampler

Brazilian Journal of Microbiology

Valéria Costa Salustiano¹  Nélio José Andrade¹  Sebastião César Cardoso Brandão¹  Raquel Monteiro Cordeiro Azeredo¹  Sandra Aparecida Kitakawa Lima¹ 

[1] ,Universidade Federal de Viçosa Departamento de Tecnologia de Alimentos Viçosa MG ,Brasil

关键词: Dairy plant;    air processing areas;    microbiological quality;    air sampler;    Indústria de laticínios;    ar de ambientes de processamento;    qualidade microbiológica;    amostrador de ar;   

DOI  :  10.1590/S1517-83822003000300015

来源: SciELO

【 摘 要 】

The microbiological air quality at processing areas in a dairy plant was evaluated by using a one-stage air sampler, based on Andersen principles (impaction technique) and by culture settling plate technique, also known as sedimentation technique. Among these areas, milk reception, packaging, and pasteurization rooms were included. Rooms where cheese, yogurt, butter and "doce de leite"(Latin American typical treat made of concentrated milk and sugar) are made were also evaluated. For all processing areas, the numbers of mesophilic aerobic bacteria and yeast and molds recovered by air sampler were higher than 90 CFU·m-3 - the maximum value recommended by American Public Health Association (APHA). In four of the six processing areas, the microbial numbers were higher than APHA's standard (30 CFU.cm-2.week-1) according to culture settling plate technique. The results showed a difference (p<0.05) for the Staphylococcus aureus numbers (from <1.0 to 4.3 UFC·m-3) at processing areas. The numbers of microorganisms recovered by impaction technique were about 2 to 10 times higher than by sedimentation technique. The microorganism group determined at processing areas depended mainly on the technique. By the air sampler technique, it was observed the predominance of yeasts and molds and by sedimentation technique, of mesophilic aerobic bacteria. The increase of temperature at processing areas did not seem to affect the numbers of airborne microorganisms. On the other hand, the increase of air humidity showed a relation with the increase of microorganism numbers. The impaction technique should be chosen since it is better to recover airborne microorganisms, including pathogens.

【 授权许可】

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