Detection and quantification of Salmonella in fresh vegetables in Perak, Malaysia

Abstract

The eating of fresh and minimally processed vegetables is getting popular among Malaysians. This trend poses an increased risk of food poisoning associated with the consumption of fresh produce contaminated with pathogenic bacteria. Salmonellosis is a foodborne disease caused by several non-typhoidal Salmonella enterica serovars, predominantly serovars Enteritidis and Typhimurium. The present study aimed to determine the prevalence of Salmonella spp., S. enterica serovar Enteritidis and S. enterica serovar Typhimurium in fresh leafy vegetables such as cabbages (n = 40), lettuces (n = 20), and fruit vegetables such as tomatoes (n = 40), carrots (n = 40) and cucumbers (n = 40), which were sold by three different hypermarkets and a wet market in Kampar, Perak, Malaysia. The study was performed over a period of 13 months (January 2018 to January 2019). A combination of most probable number-multiplex polymerase chain reaction (MPN-mPCR) method was used to quantify the concentrations of Salmonella spp., S. enterica serovar Enteritidis and S. enterica serovar Typhimurium in the examined samples. The results of this study demonstrated that of the vegetables tested, tomatoes, carrots and lettuces were not contaminated by Salmonella spp., S. enterica serovar Enteritidis and S. enterica serovar Typhimurium. However, the presence of Salmonella spp. was detected in 3.3% of cabbages from the hypermarket, with estimated microbial loads ranging from <3.0 MPN/g to 15.0 MPN/g. On the other hand, S. enterica serovar Typhimurium was detected in 10.0% of the cucumbers from hypermarkets and 20% of them from the wet market. Their microbial loads were ranging from <3.0 MPN/g to >1,100 MPN/g. This indicated that cabbages and cucumbers could be the potential sources of salmonellosis. Therefore, the monitoring of food safety and hygienic practices should be strictly enforced by relevant government agencies to avoid potential poisoning by foodborne pathogens.

Fresh vegetables and fruit as a source of <i>Salmonella</i> bacteria

“…Occurrence of Salmonella on vegetables. Literature data report that fresh vegetables can be contaminated with Salmonella bacteria [1,8,9,10,11,12,13,14,15,16]. Particularly hazardous to human health are those eaten raw, without heat treatment and only washed under running water.…”

Hubungan Pengetahuan Keamanan Pangan dengan Higiene Penjual dan Kontaminasi Salmonella spp Pada Lalapan Mentah di Kecamatan Patrang

“…Menurut penelitian di Amerika Serikat, bakteri Salmonella seringkali mengontaminasi bahan pangan seperti sayuran 7 . Penelitian lain yang dilakukan pada tahun 2020 di Malaysia menemukan adanya kontaminan Salmonella pada sayuran kubis dan mentimun mentah 8 . Kondisi ini dapat membahayakan kesehatan masyarakat Indonesia yang seringkali mengonsumsi sayuran mentah yang disebut sebagai lalapan mentah.…”

Lactic Acid Bacteria as Antibacterial Agents to Extend the Shelf Life of Fresh and Minimally Processed Fruits and Vegetables: Quality and Safety Aspects

“…Salmonella bacteria are Gram-negative and can survive in a variety of conditions, with an optimum of 37 °C, a pH of 6.5–7.0, and a water activity of less than 0.94 [ 80 , 81 ], causing significant public health burdens in many countries. Salmonellosis is a foodborne disease, mainly caused by several non-typhoidal Salmonella enterica serovars, primarily the serovars Enteritidis and Typhimurium [ 82 ].…”