Pathogen persistence on leafy vegetables
Pathogen persistence webinars:
Dr Jenny Ekman, AHR
Posts from the ‘Compost & Organic Fertilisers’ Category
Oct 22
Jul 28
Key learnings from the CPS 2020 Research Symposium
The Center for Produce Safety in the US has prepared key learnings summaries of its Annual Research Symposium, with five sessions held over June and July 2020.
The full set of Key Learnings from the CPS Research Symposium is here. The following text is drawn from the CPS Key Learnings:
During Session 1 held on June 23, 2020, the Symposium explored the use of computer-based modelling to help address two burning issues for the produce industry: understanding potential Listeria growth and persistence in whole produce commodities and the development of sampling strategies to support the validity of assumptions surrounding microbial testing needs and design of acceptable protocols (Key Learnings Session I).
In Session 2, the Symposium expanded the knowledge base on Listeria monocytogenes and its persistence and growth on specific commodities and fresh-cut products and examined novel methods to control Listeria growth on food contact surfaces (Key Learnings Session II).
In Session 3, the Research Symposium explored projects that took wholistic, systems approaches to solving challenges with pest intrusion into leafy greens fields, pathogen transference on co-managed farms and the impact of traits associated with concepts of soil health on pathogen persistence. It also examined Cyclospora presence in the irrigation canal systems in the Yuma, AZ production region (Key Learnings Session III).
Session 4 featured the use of genomics and metagenomics to address challenges in identifying new or revisited indicators and index testing-targets of human viral pathogens that may ultimately be used in the produce industry, the distribution and relatedness of Listeria species in the U.S., and the use of that information to better understand source-risk related to facilities and product, identification of competitors of Listeria monocytogenes that might control that organism in composts, and build our knowledge base of bacterial pathogen persistence and rates of genetic diversification in the Yuma and Salinas vegetable production regions (Key Learnings Session IV).
Session 5 featured research describing the “die-off” rates of human pathogens in agricultural water from three locations around the world, the persistence of pathogens in shade-house production environments, pathogen persistence in wash water systems and the potential role
of damaged cells to contaminate washed products, the efficacy of irrigation water sanitation and the potential role of sediments in canal systems as reservoirs of human pathogens (Key Learnings Session V).
Jul 10
AU: New paper on environmental drivers for pathogenic persistence
A paper has been published on “Environmental Drivers for Persistence of Escherichia coli and Salmonella in Manure-Amended Soils: A Meta-Analysis” by Dao Tran and colleagues at the ARC Training Centre for Food Safety in the Fresh Produce Industry.
The paper, which appeared in the Journal of Food Protection in July, examines 42 primary research studies on pathogen persistence from manure-amended soils, and concludes that “Based on the significant variation observed among individual field studies, it is unlikely the risks associated with the use of manure amendments containing high levels of enteric bacterial pathogens (such as in raw manure) in soils may be solely managed by a uniform exclusion period. Management of the risks associated with the use of soils amended with raw manures is best achieved through risk-based approaches incorporating differences in climate, soil management, and initial levels of bacteria during application.”
While it is recommended that only certified composted organic amendments are used in the production of fresh produce, the message is clear: risk-based approaches taking into account local environmental factors must be used by growers for determining appropriate exclusion periods after using untreated manures. More here.
Apr 17
US: Compost decomposed
Good Fruit Grower: Will increasing scrutiny of food safety practices in orchards push more growers away from using raw manure? It’s unclear at the moment, as the U.S. Food and Drug Administration is conducting a risk assessment on raw manure before it settles on a preharvest interval that will best protect crops from contamination.
Sep 18
2014 CPS Symposium Key Learnings: 10 Lessons Learned
18 September 2014
Dr Bob Whitaker & Dr Jim Gorny from the Produce Marketing Association have provided a summary of 10 key lessons from the 2014 US Centre for Produce Safety (CPS) fifth annual reseach symposium.
Jul 17
Brief Report: CPS Research Symposium Key Messages, part 1.
Brief Report, CPS Research Symposium 26 and 27th June 2013 ,Wegman’s Conference Centre Rochester, NY State.
The CPS at the University of Davis has been very supportive of the initiatives in Australia to establish an affiliated Fresh Produce Safety Centre. Over the past year they have very generously shared their research outcomes, they have given presentations to our industry, and this year invited Australian researchers to apply for research grants to work collaboratively with US scientists on issues important for the Australian fruit and vegetable industry.
