Comparison of thermophilic Campylobacter spp. occurrence in two types of retail chicken samples

The aim of this study is to compare the occurrence of thermophilic Campylobacter spp. in chicken retail at wet markets and hypermarkets. Campylobacter contaminations in chicken samples from wet market (70.7%) were comparatively lower than chicken samples sold in hypermarket (91.4%). Of the 77 Campylobacter isolates, 59 (76.6%) were identified as Campylobacter jejuni and 18 (23.4%) isolates were identified as C. coli. All Campylobacter isolates are multi-resistant to the antimicrobial agents. Most of the isolates were resistant to tetracycline (92.2%) and erythromycin (98.7%). This study concluded that chicken samples from \ud both wet market and hypermarket were contaminated with Campylobacter, most of which are antimicrobial-resistant strains

Transfer of Campylobacter jejuni from raw to cooked chicken via wood and plastic cutting boards.

Aims: We quantified Campylobacter jejuni transferred from naturally contaminated raw chicken fillets and skins to similar cooked chicken parts via standard rubberwood (RW) and polyethylene cutting boards (PE). Methods and Results: RW and PE cutting boards (2·5×2·5cm2) were constructed. RW surfaces were smooth and even, whereas PE was uneven. Scoring with scalpel blades produced crevices on RW and flaked patches on the PE boards. Raw chicken breast fillets or skin pieces (10g) naturally contaminated with Camp. jejuni were used to contaminate the cutting boards (6·25cm2). These were then briefly covered with pieces of cooked chicken. Campylobacter jejuni on raw chicken, the boards, and cooked chicken pieces were counted using a combined most-probable-number (MPN)-PCR method. The type of cutting board (RW, PE; unscored and scored) and temperature of cooked chicken fillets and skins were examined. Unscored PE and RW boards were not significantly different in regards to the mean transfer of Camp. jejuni from raw samples to the boards. The mean transfer of Camp. jejuni from scored RW was significantly higher than from scored PE. When the chicken fillets were held at room temperature, the mean transfer of Camp. jejuni from scored RW and PE was found to be 44·9 and 40·3%, respectively. Conclusions: RW and PE cutting boards are potential vehicles for Camp. jejuni to contaminate cooked chicken. Although cooked chicken maintained at high temperatures reduced cross-contamination via contaminated boards, a risk was still present. Significance and Impact of the Study: Contamination of cooked chicken by Camp. jejuni from raw chicken via a cutting board is influenced by features of the board (material, changes caused by scoring) and chicken (types of chicken parts and temperature of the cooked chicken). © 2011 The Authors. Letters in Applied Microbiology © 2011 The Society for Applied Microbiology

Detection, Isolation and Antibiotic Testing of Vibrio cholerae in seafood

Vibrio cholerae is important water borne human pathogen that associated with cholera disease. The goal of this study was to determine the prevalence and antimicrobial resistance of V. cholerae found in seafood. Samples of prawn, cockles and squid samples bought from Kuala Terengganu and Besut markets. The detection of V. cholerae in the samples was done using Polymerase Chain Reaction (PCR) assay and plating method. V. cholerae isolates were subjected to six antibiotics susceptibility test using Kirby Bauer method. In Besut district, V. cholerae was found in cockles (33%), squid (38%) and prawn (44%) in supermarket. For wet market, V. cholerae only found in squid (18%) and no detection from prawn samples. For samples collected from Kuala Terengganu supermarket, the prevalence of V. cholera in cockle was at 29%, in squid at 56% and prawn at 75%. For samples collected from wet market, V. cholerae only present in squid at 18% and no detection in prawn samples. A total of 30 V. cholerae isolates were subjected to antibiotic testing. The isolates were completely resistance towards penicillin (100%), vancomycin (80%), tetracyline (23%), gentamycin (7%), norfloxacin (3%) and ciprofloxacin (3%). This study concluded prawn, cockle and squid samples from both district were contaminated with V. cholerae. Thus, it might pose risks to consumer if undercooked contaminated seafood were consumed

Survivability of Vibrio parahaemolyticus in satar and otak-otak, Malaysian fish-based street food

Street food is popular in Asia due to its availability, low price and good taste. The safety of street food has been always questionable due to its poor handling which probably leads to microbial contamination. The objective of this study was to determine the surviving quantities of V. parahaemolyticus under various conditions in street-vended food, namely satar and otak-otak after anticipated cross-contamination to support policy and regulatory documents. The satar and otak-otak were prepared from minced and unminced fish flesh, respectively, together with other ingredients. Each satar and otak-otak were prepared with 0, 0.5, 1.5 and 3% of sodium chloride (NaCl), respectively. V. parahaemolyticus inoculum at approximately 8.66 log CFU/ml were inoculated into the samples and incubated for up to 6 h. Samples were taken at 0, 1, 3 and 6 h for enumeration of V. parahaemolyticus using spread plate method on Thiosulphate Citrate Bile Salts Sucrose (TCBS) agar. For control samples, V. parahaemolyticus was not immediately inactivated in distilled water even though significant better survivability was observed in Phosphate Buffer Saline (PBS). The numbers of V. parahaemolyticus was found to decrease by varying amounts based on the salt content and duration of holding. However, significant amounts survived to indicate potential risk

Phenotypic MicroArray (PM) profiles (carbon sources and sensitivity to osmolytes and pH) of Campylobacter jejuni ATCC 33560 in response to temperature

The present study aimed to provide an insight of C. jejuni ATCC 33560 phenotype profiles (carbon sources and sensitivity to osmolytes and pH) using Phenotypic MicroArray (PM) system in response to optimal and suboptimal temperature. C. jejuni ATCC 33560 showed utilization carbon sources from amino acids and carboxylates but not from sugars. C. jejuni ATCC 33560 is sensitive to NaCl at 2% and above but showed survival in a wide range of food preservatives (sodium lactate, sodium phosphate, sodium benzoate, ammonium sulphate and sodium nitrate). When incubated at suboptimal temperature, no phenotype loss was observed in carbon source plates. Phenotype loss of C. jejuni ATCC 33560 was observed in sodium chloride (1%), sodium sulphate (2-3%), sodium formate (1%), sodium lactate (7-12%), sodium phosphate pH7 (100mM and 200mM), ammonium sulphate pH8 (50mM), sodium nitrate (60mM, 80mM and 100mM), sodium nitrite (10mM), and growth in pH5. The phenotypic profile from present study will provide a better insight related to survival of C. jejuni ATCC 33560

Salmonella contamination in raw vegetables: A review

Raw vegetables that experience increasing demand by consumer due to the healthy nutrients. It is thought consumption of raw vegetables will help in reducing chronic diseases such as hypertension, obesity, cholesterol and diabetes. With the increasing consumption of raw vegetables, several outbreaks linked to the pathogen contamination in these vegetables have been reported worldwide. One of the most common pathogen contamination is Salmonella. Salmonella have two species which are S. bongori and S. enterica. Of these, only S. enterica that cause human infection. However, there are roughly 1500 serovars within S. enterica. Salmonella are ubiquitously present in the environment and easily contaminate food if no proper handling being practices throughout the supply chain. Various vegetables have been implicated with the contamination of Salmonella. Thus, this paper review contamination of Salmonella in vegetables from various studies and the outbreaks

Incidence and antibiogram of Vibrio parahaemolyticus in processed and frozen bivalve mollusks in Kuala Terengganu, Malaysia

This study aimed to investigate the prevalence and antibiogram of Vibrio parahaemolyticus in processed bivalve molluscs in Kuala Terengganu. A total of 80 seafood samples, namely mussels (n=20), carpet clams (n=20), cockles (n=20) and scallops (n=20), were subjected to PCR and conventional plating method for the detection of V. parahaemolyticus. V. parahaemolyticus was found in green mussels (55%), carpet clam (80%), cockles (40%) and scallops (55%). Fifty-five V. parahaemolyticus isolates were subjected to 9 types antibiotic sensitivity test using discs diffusion method. All isolates were susceptible to Tetracycline and Gentamycin. Isolates showed high resistance towards Vancomycin (52.73%), Penicillin (45.45%) and Amplicillin (32.73%). Resistance towards Amikacin, Ciprofloxacin and Norfloxacin were found to be 1.82%. It can be concluded that local bivalve molluscs were contaminated with V. parahaemolyticus and isolates showed resistance towards certain antibiotics. Therefore, consumption of raw or semi-cooked bivalve molluscs is not advisable

Thermophilic Campylobacter spp. occurrence on chickens at farm, slaughter house and retail

The aim of this study was to investigate the occurrence of campylobacters in chicken at farms (close-house system and open-house system), slaughtering (conventional slaughterhouse and processing plant) and retail (wet market and supermarket). Campylobacter spp. was not found in cloacal swabs in chickens aged of 4 weeks in farms with close-house system. Campylobacter spp. was found in cloacal swabs (95.0%) in four weeks old chicken in farms with open-house systems. End-slaughtering samples from conventional slaughterhouse and processing plant were contaminated with Campylobacter spp. at 84.0% and 94.0%, respectively. Campylobacter contamination on wet market and supermarket samples with 78.0% and 92.0%, respectively. Close-house system at farm level was able to prevent or delay Campylobacter spp. colonization in chickens but contamination by Campylobacter spp. at retail level was still high. Therefore, monitoring of Campylobacter spp. in chicken products at retail level is crucial to reduce risk of human ingestion of Campylobacter spp. through chicken products

Physicochemical Properties and Microbial Count of Bacterial Survival in Freeze Dried Goat Milk Yogurt Powder

Yogurt is a fermented milk product that has a semi-solid texture and has a short shelf life. It must be stored properly in temperature of 4ºC and below to prevent the microbial spoilage due to it high in moisture content and water activity. This study aimed to produce freeze dried goat milk yogurt powder with different percentage of honey and analyse the physicochemical as well as compare the microbial count of bacterial growth in fresh goat milk yogurt and reconstituted goat milk yogurt powder. The four formulations prepared were 6% of sugar (CY), 3% of honey with 3% of sugar (LHY), 4% of honey with 2% of sugar (MHY) and 6% of honey (HHY). The results showed each formulation has significant differences for the physicochemical analysis. The percentage of honey added into the yogurt was affected the pH value of the yogurt which have a range from pH 4.18 to 4.45. Meanwhile the results for colour analysis shown that the yellowness value of goat milk yogurt was increased as the percentage of honey added inside the yogurt was increased, as contributed by dark brown colour of honey. The bacterial survival in CY, LHY, MHY and HHY samples for fresh goat milk yogurt and reconstituted goat milk yogurt powder showed the significant different (p<0.05) with the range from 6.40 to 8.75 log cfu/ml and 5.79 to 8.07 log cfu/ml respectively. Therefore, it can be concluded that freeze drying was a suitable method to produce yogurt powder and LHY sample was the best formulation in producing the highest number of survival bacteria (log cfu/ml)

Bacillus cereus and Bacillus thuringiensis in ready-to-eat cooked rice in Malaysia

Bacillus cereus (B. cereus) isolates are toxigenic and can cause food poisoning. Cooked rice is a potentially hazardous food, especially in tropical countries. The aim of this study was to determine the prevalence of B. cereus and B. thuringiensis in raw and cooked rice marketed in Selangor, Malaysia. In this research combination of Most Probable Number - Polymerase Chain Reaction (MPN-PCR) was used to detect gyrB gene in B. cereus and B. thuringiensis. Five local varieties of raw rice samples were negative for B. thuringiensis but all (100%) were positive for B. cereus. A total of 115 cooked rice samples (nasi lemak, nasi briyani, nasi ayam and nasi putih) were studied for the presence of B. cereus and B. thuringiensis. Nasi ayam was found to have the highest prevalence (100%) of B. cereus compared to nasi putih (76.2%) and nasi lemak (70.4%). Nasi briyani had the lowest prevalence (50%) of B. cereus. The frequencies of B. thuringiensis were found to be 10, 30 and 35.2 % in nasi putih and nasi ayam, nasi briyani and nasi lemak, respectively. The range of B. cereus and B. thuringiensis in the samples was from 1100 MPN/g) while nasi ayam showed less contamination (460 MPN/g) with B. cereus which was significantly different (P 1100, 93, 9.2 and 3.6 MPN/g, respectively