FDA Reports on Sampling Project for Pathogens in RTE Dips and Spreads

FDA released a report on their sampling of RTE dips and spreads for Listeria and Salmonella. The concern is that these products will have post-lethality (after pasteurization) exposure during additional  processing such as mixing before packaging where they can be subject to recontamination.  (Ingredient contamination can also be an issue of course)  Once packaged, the product is held under refrigeration conditions, generally having a long shelf-life, and then consumed, as is, by the consumer...often served with chips or veggies as a vehicle to scoop the product and deliver it by hand to the mouth   (I think you know the process.)  FDA points out the issue with these products.

"Over the past few years, there have been a few outbreaks and many recalls of dips and spreads. In FY2019, there were two outbreaks of Salmonella linked to Tahini (12 confirmed cases, 1 hospitalizations). In FY2017, there were two outbreaks of L. monocytogenes linked tohummus (31 confirmed cases, 26 hospitalizations, 3 fetal losses); one of the outbreaks may have contributed to 3 deaths. These past outbreaks and recalls are what prompted FDA to initiate this surveillance sampling assignment to survey the industry, perform follow-up inspections to positive samples to identify potential routes and sources of contamination, when possible, and ensure potentially contaminated product was removed from the retail market to protect public health."

The top items sampled included hummus (336), cheese spread (82) cheese and vegetable spread (65), dairy [sour cream type?] (63), cheese and pepper (54), dairy and vegetable [sour cream and oinion?], and salsa (37).

Out of the 747 samples tested in this assignment, four were detected to have a human pathogen

Salmonella - The agency detected Salmonella spp. in one hummus sample collected from a retail establishment in Kingsburg, CA. The FDA detected the serovar Salmonella Havana in one of the two composites. Upon detecting Salmonella spp., the FDA performed Whole Genome Sequencing (WGS) analysis on the organism and determined that it did not match any known human illnesses and was not linked to any other product or environmental samples.

Listeria - The FDA detected Listeria monocytogenes in three dips and spreads samples – two cheese samples, one cheese and pepper sample – collected from a retail establishment in Colorado Springs, CO. All three of the samples contaminated with L. monocytogenes were produced by the same manufacturer. After detecting L. monocytogenes, the agency conducted WGS analysis on the organisms and determined they did not match any known human illnesses and were not linked to any other product or environmental samples.

The agency’s finding of three positive product samples and over 23 positive environmental samples all from one firm indicates that the controls that firm established were not effective at significantly minimizing or preventing L. monocytogenes from contaminating their RTE finished products. The large number of positive environmental samples found in the follow-up inspection indicates the firm had not implemented effective sanitation controls. 

https://www.fda.gov/food/sampling-protect-food-supply/fy21-22-sample-collection-and-analysis-domestic-refrigerated-rte-dips-and-spreads
FY21-22 Sample Collection and Analysis of Domestic Refrigerated RTE Dips and Spreads

In 2021, the U.S. Food and Drug Administration (FDA) conducted a routine assignment to collect domestic multi-commodity ready-to-eat (RTE) refrigerated dips and spreads to test for Listeria monocytogenes and Salmonella spp. The agency’s goal in conducting this assignment was to determine the presence of these pathogens in RTE dips and spreads and remove adulterated product from the market, when possible. This sampling assignment started in early March 2021 and sample collection and analysis completed in January 2022.

This assignment is part of the FDA’s risk-based approach to food safety, as outlined in the FDA Food Safety Modernization Act (FSMA). The agency is reviewing this assignment’s findings to identify common factors or patterns (e.g., origin, variety, manufacturing practices) related to the contamination of RTE dips and spreads, when possible. This data will help FDA develop guidance and update program priorities, including sampling assignments and the prioritization of surveillance inspections.

Background

Refrigerated dips and spreads is a broad and growing category of food that encompasses a diverse range of products including hummus, tahini, pimento cheese, and yogurt-based products. A “dip” is thinner in consistency and another piece of food (e.g., chip, vegetable) is submerged into it, such as salsa. A “spread” is food that is spreadable, usually with a knife, onto other foods (e.g., bread, crackers), such as pimento cheese.

Many Americans purchase refrigerated RTE dips and spreads for quick and nutritious snacks. In response to consumers’ lifestyles and preferences, dips and spreads manufacturers have created on-the-go and portion control packaging.[1] In 2020, 191.14 million Americans used dips as snacks.[2] As the popularity of plant-based diets continues to grow, so does the consumer demand for RTE dips and spreads. U.S. refrigerated plant-based dip annual sales increased from about three million dollars in April 2016 to about 11 million dollars in April 2019.[3]

RTE foods can become contaminated through environmental pathogens (i.e., harborage and cross-contamination within the food manufacturing environment/process) or contaminated ingredients (i.e., during or after processing). Dips and spreads may have pH and water activity that make it easy for bacteria to survive and grow, if present. Consumers typically eat these dips and spreads without a ‘kill step,’[4] such as cooking, to reduce or eliminate any pathogenic bacteria that may be present. As such, dips and spreads contaminated with L. monocytogenes or Salmonella can present a significant public health risk and have been associated with multiple recalls over the past few years. This assignment was established due to the five recalls of hummus products and six recalls of multi-commodity dips due to contamination with L. monocytogenes or Salmonella from FY2017 through FY2020.

Findings

Out of the 747 samples tested in this assignment, four were detected to have a human pathogen. The FDA shared these findings with the responsible firms and determined appropriate follow up as described below.

Pathogen Findings: Salmonella

The agency detected Salmonella spp. in one hummus sample collected from a retail establishment in Kingsburg, CA. The FDA detected the serovar Salmonella Havana in one of the two composites. Upon detecting Salmonella spp., the FDA performed Whole Genome Sequencing (WGS) analysis on the organism and determined that it did not match any known human illnesses and was not linked to any other product or environmental samples.

Pathogen Findings: Listeria monocytogenes

The FDA detected Listeria monocytogenes in three dips and spreads samples – two cheese samples, one cheese and pepper sample – collected from a retail establishment in Colorado Springs, CO. All three of the samples contaminated with L. monocytogenes were produced by the same manufacturer. After detecting L. monocytogenes, the agency conducted WGS analysis on the organisms and determined they did not match any known human illnesses and were not linked to any other product or environmental samples.

During the assignment, the agency also detected two subspecies (i.e., Listeria welshimeri, Listeria innocua) of non-pathogenic Listeria spp. in three samples – two samples collected from retail establishments and one sample collected from the manufacturer/processor. Since these samples were non-pathogenic, they were not analyzed by WGS.

The agency submitted the WGS results for the Salmonella spp. and L. monocytogenes pathogenic findings to the national GenomeTrakr database.

Discussion

Over the past few years, there have been a few outbreaks and many recalls of dips and spreads. In FY2019, there were two outbreaks of Salmonella linked to Tahini (12 confirmed cases, 1 hospitalizations). In FY2017, there were two outbreaks of L. monocytogenes linked tohummus (31 confirmed cases, 26 hospitalizations, 3 fetal losses); one of the outbreaks may have contributed to 3 deaths. These past outbreaks and recalls are what prompted FDA to initiate this surveillance sampling assignment to survey the industry, perform follow-up inspections to positive samples to identify potential routes and sources of contamination, when possible, and ensure potentially contaminated product was removed from the retail market to protect public health.

In the absence of good manufacturing practices and implementation of preventive controls, pathogens can become resident strains which put a firm’s food products at increased risk of contamination from the manufacturing environment. The findings of this assignment suggest that Salmonella spp. and L. monocytogenes were not widespread in the multi-commodity RTE dips and spreads collected nationwide. Since the three L. monocytogenes positives were from the same manufacturer and collected on the same day and retail establishment, these are not representative of the entire population of cheese dips and spreads.

The FDA cautions against making inferences more broadly about the contamination or potential for contamination of RTE dips and spreads based solely on this assignment’s findings. However, the presence of contamination in the samples suggests the risk of contamination still exists. For example, from FY2017 through FY2022, there were a total of 22 recalls of dips and spreads due to potential Salmonella or L. monocytogenes contamination; of these hummus and cheese dips and spreads make up 64% of the recalls (10 hummus recalls, 4 cheese dips and spread recalls).

As stated in the “Findings” section, the FDA detected Salmonella spp. in one sample and L. monocytogenes in three samples out of the 747 collected and tested samples. All four of the positive samples were collected from retail establishments. None of the positive findings were linked to any known human illness, though, based on the agency’s WGS analysis.

The agency’s finding of three positive product samples and over 23 positive environmental samples all from one firm indicates that the controls that firm established were not effective at significantly minimizing or preventing L. monocytogenes from contaminating their RTE finished products. The large number of positive environmental samples found in the follow-up inspection indicates the firm had not implemented effective sanitation controls. The agency followed up to ensure the business implemented corrective actions to the previously identified deficiencies and no contaminated or potentially contaminated products entered commerce. The firm ultimately made the decision to discontinue their manufacturing operations.

As noted in the “Background” section, RTE dips and spreads can be contaminated with pathogenic bacteria and can support their survival and/or growth. Since refrigerated RTE dips and spreads do not undergo a ‘kill step’ prior to consumption, consumers should immediately refrigerate or freeze this commodity to reduce the potential for pathogen growth. Once a frozen RTE dip or spread is thawed for use, do not refreeze it. To reduce the risk of foodborne illness, consumers should read and follow the package instructions for use and storage on RTE dips and spreads. When serving RTE dips and spreads on a buffet, make sure to keep cold foods cold (at or below 40 °F) – by placing shallow food containers inside a pan filled with ice – and hot foods hot (at or above 140 °F) – by using chafing dishes, warming trays, or slow cookers.

FDA Releases Summary Report on Ready-to-Eat Dips and Spreads Sampling Assignment
Constituent Update
June 15, 2023

Today, the U.S. Food and Drug Administration (FDA) released findings from a sampling assignment that collected and tested refrigerated, multi-commodity ready-to-eat (RTE) dips and spreads. The assignment sought to estimate the presence of Salmonella spp. and Listeria monocytogenes in these products as part of the FDA’s ongoing effort to proactively ensure food safety and remove adulterated product from the market.

More than 190 million Americans purchased refrigerated RTE dips and spreads in 2020, and as the popularity of plant-based diets, as well as the convenience of on-the-go packaging continues to grow, so does consumer demand for these products.

From March 2021 to January 2022, the FDA collected and tested a total of 747 samples of refrigerated, multi-commodity RTE dips and spreads that contain ingredients such as sesame, vegetables, cheese, and seafood. The agency detected Salmonella spp. in one sample of hummus and Listeria monocytogenes in three dip and cheese spread samples. The FDA worked closely with the manufacturers to remove the contaminated products from the market.

Dips and spreads contaminated with Listeria monocytogenes or Salmonella can present a significant public health risk and have been associated with multiple recalls over the past few years. This assignment was carried out because from FY2017 through FY2020 there were five recalls of hummus products and six recalls of multi-commodity dips that were contaminated with L. monocytogenes or Salmonella.

The findings of this assignment underscore the need for processors of RTE dips and spreads and others in the supply chain to comply with the FDA’s Current Good Manufacturing Practice, Hazard Analysis, and Risk-Based Preventive Controls for Human Food Rule, as applicable.

The FDA is reviewing this assignment’s findings to identify common factors or patterns related to the contamination of RTE dips and spreads. This data will help the agency develop guidance and update program priorities, including future sampling assignments and the prioritization of surveillance inspections. The FDA will continue to sample RTE dips and spreads for pathogens as warranted to protect consumers.