Examination of Microbiological Contamination of Ready-to-eat Vegetable Salad

즉석 섭취 야채샐러드의 미생물 오염조사

  • Published : 2004.06.01

Abstract

120 samples of ready-to-eat salad product were purchased at department stores, marts and family restaurants in metro area. Coliform bacteria and food borne pathogenic bacteria were isolated from these samples. In 73 samples among the 120 salad product samples, coliform bacteria and food borne pathogenic bacteria were detected by 60.8% of isolated rate. Salad were classified into organic and non-organic salad. According to a salad type, salad were classified into vegetable salad and mixed vegetable salad with fried chicken and extra food. According to a packing type, packed salad product and salad-bar product were classified. After the classification, the results of each cases were compared. There is no statistical relation between cultivation or packing methods and contaminated bacteria. But the incidence number of microbial strains was significantly different between vegetable salad and mixed vegetable salad(p<0.005). In vegetable salad, more various strains were detected. E. coli was isolated in 10 cases among the 90 cases in non-organic vegetable and in 7 cases among the 30 cases in organic salad. Food borne pathogenic bacteria were isolated in non-organic vegetable salad product. Staphylococcus aureus was isolated in 4 cases of vegetable salad product and Salmonella spp. isolated in 1 case. After 5 times examination of each 4 market products, the total number of aerobic bacteria was average 4.8$\pm$0.19 log cfu/g. One sample from this product, saline and a detergent for vegetable were used for 3 minutes to notice the effect. As a result, when saline was used 5 times and detergent for vegetable was used 1 time, bacterial contamination was decreased up to 95.5%.

식용이 간편한 즉석섭취용(ready-to-eat)샐러드 제품의 수요는 나날이 증가하고 있으나 국내 유통 샐러드의 미생물 오염수준은 기준 및 규격이 설정되어있지 않고 그 수준 또한 알려져 있지 않다. 따라서 소비가 집중되어 있는 대도시 지역을 중심으로 백화점, 대형할인점 또는 패밀리레스토랑 등에서 판매되는 즉석섭취용 샐러드 제품 120건을 대상으로 하여 coliform bacteria, E. coli, E. coli O157:H7, Staphylococcus aureus, Salmonella spp. Listeria monowtogenes 및 Bacillus cereus의 분리시험을 실시하고 일부 제품을 대상으로 일반세균수 및 세척효과를 조사하였다. 제품 120건 중 총 73건에서 coliform bacteria 등이 검출되어 60.8%의 검출율을 보였다. 5. coli가 17건, Staphylococcu aureu가 3건, Salmonella spp.가 1건에서 각각 검출되었고 기타 coliform bacteria는 59건에서 검출되었다. 샐러드는 양식방법에 따라 유기농샐러드와 비유기농샐러드로 나누었고, 종류는 야채로 구성된 야채샐러드와 튀긴 닭 등이 첨가된 혼합샐러드로 나누었으며 판매형태에 따라 완포장제품과 샐러드바 제품으로 나누었다. 양식방법 및 포장방법과 미생물오염과의 통계적 연관성은 없는 것으로 나타났다. 그러나 분리된 균주 수에 있어서는 야채샐러드와 혼합샐러드 간에 통계적으로 유의한 차를 보여 야채샐러드의 경우 좀 더 다양한 균종이 분리되는 것으로 나타났다 (p<0.005). E. coli는 일반 재배 야채샐러드의 경우 90건 중 10건에서 분리되었고 유기농재배 야채샐러드 의 경우 30건 중 7건에서 분리되었다. 식중독 원인균은 비유기농 재배 야채샐러드 4건에서 Staphylococcus aureu가, 1건에서 Salmonella arixonia가 검출되었으나 유기농재배 야채에서는 검출되지 않았다. 널리 판매되는 일부 제품 4종을 5회에 걸쳐 검사한 결과 총 호기성 세균수는 평균 4.8$\pm$0.19 log$_{10}$ cfu/g으로 조사되었다. 같은 제품을 생리식염수와 야채용세척제를 이용해 3분간 침지 후 세척효과를 본 결과 생리식염수는 5회, 야채용세척제는 1회 세척 시 95.5%의 세척효과를 내는 것으로 나타났다.다.

Keywords

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