In the news

A study published in Pathogens (2019, 8(4), 218) describes the work of a research team from Flinders University in Adelaide, Australia, that developed a method to remove Salmonella Typhimurium (ST) from eggshells without effecting the egg’s usability and quality. The research investigated the effect of pH and temperature on the survival of Salmonella Typhimurium (ST) in peptone water (PW) and mayonnaise. The pH of PW and mayonnaise was adjusted to 4.2, 4.4, and 4.6 using acetic acid and vinegar, respectively. The PW and mayonnaise were inoculated with ST and incubated at 37 °C, 23 °C, and 4 °C. The survival of Salmonella was determined using the drop plate method. Survival was significantly (p < 0.05) improved at 4 °C. In both mayonnaise and PW, following 24 h, there was no ST growth at pH 4.2. Resuscitation of ST was rapidly observed at 4 °C, while complete inactivation was observed at 37 °C at pH 4.2, 4.4, and 4.6 in both PW and mayonnaise. Lower temperatures protected ST from the bactericidal effect of low pH. This study showed that lower temperatures reduce the antibacterial activity of the organic acids, which allowed Salmonella to survive at low pH for longer. Preparing home-made mayonnaise at pH 4.2 and retaining at room temperature for at least 24 h effectively killed S. Typhimurium and could aid in reducing the prevalence of the salmonellosis outbreaks in Australia. Results of this study indicate that the combined effect of pH 4.2 and the incubation temperature, 37 °C was the most effective at reducing S. Typhimurium; however, incubating at 23 °C was still more effective than 4 °C and may present a more practical approach.  @ https://www.mdpi.com/2076-0817/8/4/218/htm

Blendtopia Products, LLC is recalled 29,078 cases of 7 ounce frozen Blendtopia brand Superfood Smoothie Kits due to potential contamination with Listeria monocytogenes. The smoothie blends affected include Blendtopia brand “Glow,” “Detox,” “Energy,” “Immunity,” and “Strength” Superfood Smoothie Kits.  The products were distributed nationwide and are sold at select retailers and online.

The problem was discovered during the quality control processes. The issue is believed to be isolated to a supplied ingredient. There have been no reports of sickness or illness to date associated with any consumption of products related to this recall. No other products made by Blendtopia Products, LLC, are affected by the recall. @ https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/blendtopia-products-llc-voluntarily-recalls-frozen-smoothie-products-due-possible-health-risk

Nuts ‘N More LLC from East Providence, RI recalled 4143 plastic jars of Plain Peanut Spread due to Listeria species.  The product was distributed to locations in VA, AZ, MA, RI, ME, AL, IN, FL, as well as Canada and the UK. No complaints of illness have been reported to date. Routine testing performed by a 3rd Party Laboratory revealed the presence of Listeria species. The company has ceased the production and distribution of this product as the State of Rhode Island and the company continues its investigation. @ https://www.fda.gov/safety/recalls-market-withdrawals-safety-alerts/nuts-n-more-llc-recalls-plain-peanut-spread-because-possible-health-risk

An article was published in Chemistry World describing a test developed at the University of California, Irvine to diagnosing bacterial infection and whether the bacteria contain a variety of antibiotic resistance genes.  The test is sensitive (10–100 times better than existing methods) and provides the results within an hour. The assay can analyze whole blood and uses the polymerase chain reaction. The test eliminates the need for sub-culturing of the blood. The method uses a microfluidic device that mixes the whole blood sample with PCR reagents, which work with whole blood, and then turn this mixture into millions of individual picolitre-sized droplets. After the PCR reaction, droplets containing particular genetic targets become fluorescent and are detected and quantified by a high throughput 3D particle counter. As the sample is being analyzed, the counter moves the sample up and down, and rotate it. The test allows the use of one milliliter of blood and the higher volume increases the probability of detecting bacteria. @ https://www.chemistryworld.com/news/test-for-antibiotic-resistance-genes-provides-answers-within-an-hour/4011130.article