Category Archives: Research

Research – Determination of Histamine in Japanese Spanish Mackerel (Scomberomorus niphonius) Meat Implicated in a Foodborne Poisoning

Journal of Food Protection

ABSTRACT

An incident of foodborne poisoning causing illness in seven victims due to ingestion of fried Japanese Spanish mackerel (JS mackerel; Scomberomorus niphonius) meat occurred in September 2014 in Hualien County, eastern Taiwan. Of the two suspected fish meats, one raw sample contained 3,318 ppm of histamine and one fried sample contained 1,906 ppm of histamine, levels which are greater than the potential hazard action level (500 ppm) in most illness cases. Given the allergy-like symptoms of the victims and the high histamine content in the suspected fish samples, this foodborne poisoning was strongly suspected to be caused by histamine intoxication. In addition, five histamine-producing bacterial strains isolated from suspected raw fish samples, capable of producing 152 to 1,020 ppm of histamine in Trypticase soy broth supplemented with 1.0% l-histidine, were identified as Hafnia alvei (one strain), Enterobacter aerogenes (two strains), Raoultella ornithinolytica (one strain), and Morganella morganii (one strain) by 16S rDNA sequencing with PCR amplification. Moreover, 12 raw fish samples and 39 fried fish samples from retail stores were collected and tested to determine the occurrence of histamine. Two of 12 commercial raw fish samples (16.7%) had histamine levels greater than the U.S. Food and Drug Administration guideline for decomposition of 50 ppm for scombroid fish or product or a combination of both. To our knowledge, this is the first report in Taiwan to demonstrate that the JS mackerel meat products could cause histamine intoxication.

HIGHLIGHTS
  • To our knowledge, this is the first report in Taiwan that JS mackerel causes histamine intoxication.

  • High histamine (>1,900 ppm) content found in both suspected fish samples.

  • Four prolific histamine-forming isolates produce >541 ppm of histamine in TSBH.

  • Higher levels of histamine, APC, TVBN, and coliforms found in some commercial fish samples.

Research – Your energy-efficient washing machine could be harbouring pathogens

Science Daily 

For the first time ever, investigators have identified a washing machine as a reservoir of multidrug-resistant pathogens. The pathogens, a single clone of Klebsiella oxytoca, were transmitted repeatedly to newborns in a neonatal intensive care unit at a German children’s hospital. The transmission was stopped only when the washing machine was removed from the hospital. The research is published this week in Applied and Environmental Microbiology, a journal of the American Society for Microbiology.

Research – Effectiveness of Food Handler Training and Education Interventions: A Systematic Review and Meta-Analysis

Journal of Food Protection

ABSTRACT

Improper food handling among those working in retail and food service settings is a frequent contributor to foodborne illness outbreaks. Food safety training and education interventions are important strategies to improve the behaviors and behavioral precursors (e.g., knowledge and attitudes) of food handlers in these settings. We conducted a comprehensive systematic review to identify, characterize, and synthesize global studies in this area to determine the overall effectiveness of these interventions. The review focused on experimental studies with an independent control group. Review methods included structured search strategy, relevance screening of identified abstracts, characterization of relevant articles, risk of bias assessment, data extraction, meta-analysis of intervention effectiveness for four outcome categories (attitudes, knowledge, behavior, and food premise inspection scores), and a quality of evidence assessment. We identified 18 relevant randomized controlled trials (RCTs) and 29 nonrandomized trials. Among RCTs, 25 (64%) unique outcomes were rated as high risk of bias, primarily owing to concerns about outcome measurement methods, while 45 (98%) nonrandomized trial outcomes were rated as serious risk of bias, primarily because of concerns about confounding bias. High confidence was identified for the effect of training and education interventions to improve food handler knowledge outcomes in eight RCT studies (standardized mean difference = 0.92; 95% confidence interval: 0.03, 1.81; I2 = 86%). For all other outcomes, no significant effect was identified. In contrast, nonrandomized trials identified a statistically significant positive intervention effect for all outcome types, but confidence in these findings was very low due to possible confounding and other biases. Results indicate that food safety training and education interventions are effective to improve food handler knowledge, but more evidence is needed on strategies to improve behavior change.

HIGHLIGHTS
  • Food safety training and education interventions improve food handler knowledge.

  • There is low confidence that these interventions improve other food safety outcomes.

  • Risks of bias were present for most study outcomes.

  • Further research is needed on strategies that can change food handler behaviors.

USA – Whole Genome Sequencing Solves Cake Mix Salmonella Outbreak

Food Poisoning Bulletin

For the first time, whole genome sequencing solved a Salmonella outbreak associated with cake mix, according to a study published in the Center For Disease Control and Prevention’s Weekly Morbidity and Mortality Report. This cake mix Salmonella outbreak was associated with Duncan Hines products.

Whole Genome Sequencing Solves Cake Mix Salmonella Outbreak

Research -Interaction of Gaseous Chlorine Dioxide and Mild Heat on the Inactivation of Salmonella on Almonds

Journal of Food Protection

ABSTRACT

The interactive effects of mild heat and gaseous chlorine dioxide (ClO2) on populations of Salmonella on almonds were studied. Almonds, dip inoculated with a two-strain cocktail of attenuated Salmonella Typhimurium, were treated with three concentrations of ClO2 at ambient temperature (ca. 22°C), and at 45, 50, 55, and 60°C for 4 h and with more than 90% relative humidity. Concentrations of ClO2 during treatments were measured, and populations of Salmonella were determined following treatments. Results demonstrated that ClO2 at concentrations of more than 4 mg/L and ambient temperature only reduced populations of Salmonella by 1.46 log CFU/g. With increasing treatment temperature, the efficacy of gaseous ClO2 increased. At 55 and 60°C, >1 mg/L ClO2, and a 4-h treatment time, >4 log CFU/g Salmonella was inactivated. Reductions greater than 4 log of the bacterium by gaseous ClO2 at 55°C were confirmed using a three-strain cocktail of pathogenic Salmonella. Overall, results demonstrated that mild heating is necessary for gaseous ClO2 to achieve more than 4 log CFU/g inactivation of Salmonella on almonds.

HIGHLIGHTS
  • ClO2 applied at ambient temperature achieves less than 2-log reductions of Salmonella.

  • Mild heat and ClO2 have a synergistic effect on the reduction of Salmonella.

  • Surrogate Salmonella Typhimurium and pathogenic Salmonella behave similarly to ClO2 and heat.

Research – Pathogens removed from cows’ drinking water

Dairy Global

Successful trials to remove potentially harmful pathogens, Clostridium perfringens, from drinking water given to cows have received funding for further research after first trials found it increased calf health and size and reduced the need for antibiotic treatment.

“The trials show great promise for the agricultural sector in the UK with potential for farmers to deliver healthier calves with a reduced requirement for antibiotic treatment and ultimately higher yields and increased profitability from their dairy herd,” said Ian Tremain, agriculture innovation manager at Bridgwater & Taunton College.

WET Group, which supplied the technology used to clean the borehole water commonly mixed with artificial nutrition feed and then fed to cows, worked with the Agriculture Innovation Centre at Bridgwater & Taunton College on the year-long trial on cows, and has decided to fund further trials in order to expand on initial findings. The final phase of the trials, which will see the introduction of WET Group’s upgraded mineral enhanced Guided Enhanced Membrane (GEM) system is due to commence in October 2019.

Research – Effect of Tartary Buckwheat Peptides on Shelf Life of Tilapia (Oreochromis niloticus) Fillets

Journal of Food Protection

ABSTRACT

Tartary buckwheat peptides (TBPs), produced from tartary buckwheat through solid-state fermentation, were used as a dip treatment solution to preserve tilapia fillets. Fillets were dip treated with different concentrations of TBPs (0.5, 1, and 2% [v/v]) and stored at 4°C for 12 days. The effect of TBPs on thiobarbituric acid, total volatile base nitrogen, surface color, texture profile analysis, total viable counts, and changes in sensory properties of tilapia fillets during storage was investigated. Compared with the control group, the groups treated with TBPs displayed reduced rates of quality deterioration in physicochemical, bacteriological, and sensory characteristics. Based on total volatile base nitrogen content, total viable counts, and sensory scores, the shelf life of control tilapia fillets was 4 days and that for TBP-treated fillets was 8 days, twice as long as that of the control group. Thus, TBPs can be used as preservatives to maintain the quality and extend the shelf life of tilapia fillets stored at 4°C.

Ireland – Sushi Production and Outlets Cause for Concern – Audit Published

FSAI

The Food Safety Authority of Ireland (FSAI) today released the findings of a targeted audit that shows an unacceptable level of non-compliance by sushi production and processing facilities in Ireland. The audit of sushi manufacturers, restaurants and takeaway outlets revealed 76 breaches of food safety regulations, with some 90% of the businesses audited not having adequate controls in place to safeguard human health. All food businesses are legally obliged to have robust food safety control systems in place, however of the 11 premises audited, only one premises had no breaches of food safety and hygiene legislation. The audit was undertaken due to a reported 80% increase in the number of restaurants offering sushi since 2018. To coincide with the audit being published today, the FSAI has produced new advice on the safe production of sushi to assist sushi producers to comply with the law and the advice is available on: https://www.fsai.ie/faq/safe_production_sushi.html

Research – Control of pathogens in fresh pork sausage by inclusion of Lactobacillus sakei BAS0117

Canadian Journal of Microbiology

ABSTRACT

A pork sausage was produced with low sodium content (1.64%) to which Lactobacillus sakei was added with the aim of developing a meat pork sausage for cooking and having technological, organoleptic, and hygienic advantages. The lactic acid bacteria (LAB) L. sakeiLactococcus sp., and Pediococcus pentosaceus were submitted to extreme pH, temperature, and NaCl conditions. Lactobacillus sakei was used in pork sausage because of its resistance to different culture conditions and its antimicrobial potential. The food-borne pathogens Listeria monocytogenes Scott A, Enterococcus faecalis, and Staphylococcus aureus were used as indicator microorganisms to evaluate the antimicrobial activity of selected LAB strains. Salmonella enterica serotype Choleraesuis is a common pathogen of pigs. To the raw sausage product containing L. sakei and nonpathogenic endogenous microbiota, we added about >104 and <105 CFU/g of S. enterica serotype Choleraesuis to evaluate the inhibitory potential of L. sakei towards this pathogen. Salmonella Choleraesuis was inhibited in the presence of Lsakei over 7 days of storage of the meat product (about 3.0 log cycles reduction). Lactobacillus sakei significantly increased inhibition when compared with the nonfermented sausage. Thus, L. sakei BAS0117 played an important role as an additional hurdle in the fermented meat pork sausage during storage.

Research – How 26 Percent of Participants Transferred Bacteria from Raw Chicken to Their Salads

USDA

The debate on whether or not to wash raw poultry is a fierce one, but until recently it was not a debate backed by science. A recent study from the U.S. Department of Agriculture (USDA) further demonstrates that individuals are putting themselves at risk of illness when they wash or rinse raw poultry.

“During this year’s study, 26 percent of participants that washed raw poultry transferred bacteria from that raw poultry to their ready to eat salad lettuce,” said Dr. Mindy Brashears, the USDA’s Deputy Under Secretary for Food Safety. “Fortunately, small changes in the kitchen can lead to big health benefits for you and your family. Not washing meat and poultry reduces your risk of cross-contamination and can keep your family safe from foodborne illness.”

Many individuals may be unknowingly contaminating foods and causing illness for themselves or their family members. The good news is that the USDA has a few easy options to help prevent illness when you are preparing meat and poultry.

  • Significantly decrease your risk by preparing foods that will not be cooked, such as vegetables and salads, BEFORE handling and preparing raw meat and poultry.
    • Of the participants who washed their raw poultry, 60% had bacteria in their sink after washing or rinsing the poultry. Even more concerning was that 14% of participants still had bacteria in their sinks after they attempted to clean the sink.
  • Thoroughly clean and sanitize ANY surface that has potentially touched or been otherwise contaminated from raw meat and poultry, or their juices.
    • Of the participants that did not wash their raw poultry, 31% still managed to get bacteria from the raw poultry onto their salad lettuce.
    • This high rate of cross-contamination was likely due to a lack of effective handwashing and contamination of the sink and utensils.
      • Clean sinks and countertops with hot soapy water and then apply a sanitizer.
      • Use one cutting board for raw meat and poultry a different one for fruit, vegetables and cooked foods.
      • Wash hands immediately after handling raw meat and poultry. Wet your hands with water, lather with soap and then make sure you scrub your hands for 20 seconds.
  • Destroy any illness causing bacteria by cooking meat and poultry to a safe internal temperature as measured by a food thermometer.
    • Beef, pork, lamb and veal (steaks, roasts and chops) are safe to eat at 145°F.
    • Ground meats (burgers) are safe to eat at 160°F.
    • Poultry (whole or ground) are safe to eat at 165°F.
      • Washing, rinsing, or brining meat and poultry in salt water, vinegar or lemon juice does not destroy bacteria.

If you would like to talk about different options for preventing foodborne illness, you are in luck! You can call the USDA Meat and Poultry Hotline (1-888-674-6854) Monday through Friday, from 10 a.m. to 6 p.m. ET, or email or chat at AskKaren.gov.