California Ag Network

Tag: CDC

  • USDA Scientists Develop Technology to Reduce Pathogens in Intact Eggs

    Radio Frequency unit. (Photo by Joseph Sites, ARS)

    CDC estimates Salmonella bacteria causes about 1.35 million infections, 26,500 hospitalizations, and 420 deaths in the United States every year. Despite their appearance in everyday meals and snacks, the truth is that raw eggs and egg products can carry Salmonella and cause foodborne illness and outbreaks, and even death, in some circumstances. But researchers at the U.S. Department of Agriculture (USDA) recently found a way to combat this through Radio Frequency (R.F.) technology.

    A simple solution to foodborne pathogens in eggs would be to pasteurize all raw eggs before they are consumed; however, less than 3 percent of commercial eggs are pasteurized in the United States. Conventional thermal pasteurization of intact eggs is usually a long process that involves submerging eggs in hot water for more than 57 minutes to inactivate Salmonella cells. Researchers at the Agricultural Research Service’s (USDA-ARS) Eastern Regional Research Center in Wyndmoor, Pa., used a novel thermal technology that pasteurizes eggs and inactivates Salmonella cells with a short processing time.

    During the study, the water molecules inside the egg rotate and align with the RF instrument’s electric field. This molecular friction causes the liquid inside the egg to heat up quickly and subsequently reduce Salmonella by 99.999 percent within 24 minutes. The R.F.-processed eggs were transferred to the refrigerator and kept at 7°C for seven days to simulate the commercial cold chain temperature.

    “After treatment with the system, no intact Salmonella or sub-lethal Salmonella cell remnants were recovered, and no cell recovery was found in the R.F. – treated eggs when stored at retail refrigerated temperature,” said USDA-ARS Research Food Technologist Daniela Bermudez-Aguirre. “The egg quality, such as the color and other parameters, were also preserved through the processing.”

    This technology has shown several advantages when used in food, all without a negative effect on food quality. Statistics also show that Americans consumed a total amount of 93.1 billion eggs in 2023. So, this is a promising advancement for small farmers or egg processors and can ensure food-safe eggs while minimizing Salmonella. Consumers will also benefit from this technology since it preserves the quality of the eggs that can be used for special markets such as nursing homes, hospitals, or schools.

    ARS researchers will continue to develop this technology’s capabilities and expect it to be commercially available in the near future.

    The Agricultural Research Service is the U.S. Department of Agriculture’s chief scientific in-house research agency. Daily, ARS focuses on solutions to agricultural problems affecting America. Each dollar invested in U.S. agricultural research results in $20 of economic impact.

  • Paso Robles Soil Health Project Looking for Participants

    The Paso Robles Wine Country Alliance and Upper Salinas Las Tablas RCD is working with a team of California soil scientists and extension agents (Dr. Cristina Lazcano, Dr. Kerri Steenwerth, Dr. Charlotte Decock, Mark Battany and others) to study soil health, and the potential for carbon sequestration in vineyard soils of Paso Robles. Our goals include developing real metrics for what a “healthy soil” is for premium wine grapes, and as we learn, educating our members and all growers on what practices best impact soil health, carbon sequestration, and a reduction in greenhouse gas emissions in our vineyards. This study is funded through the American Vineyard Foundation. We are now recruiting collaborating growers in the Paso Robles AVA. Are you willing to participate in the next phase of this exciting research project?

    BACKGROUND

    In the last years there has been a big push for growers to incorporate practices that improve or preserve soil health. However, there are not yet clear guidelines on how much the health of a particular soil can be improved given certain management practices. There is also no information on how soil health may be important for wine grape production as compared to other crops. This project aims to determine the variability of soil health indicators (soil organic matter, infiltration etc.) in areas with different soil types and climate in Paso Robles.

    GROWER COMMITMENT

    • Allow our researchers to collect soil samples and perform soil health assessment during the 2022 late winter months (aiming for February 2022). They would like to sample from blocks that have high vs. low soil health/vigor. (approx. 2 hours needed).
    • Participate in an interview (approx. 1 hour long) to discuss what aspects of soil health you consider important for wine grape production, and the practices that you are using to promote soil health. Interviews can be done at the time of sampling, or at a different time either in person or remotely (through Zoom).
    • Approx. 3 hours total time commitment
      

    SAFETY PROTOCOLS

    • At all times, the researchers will adhere to strict COVID-19 safety protocols as directed by the CDC, OSHA and adhering to the specific practices that each grower has in place for your operation.
      

    Thank you in advance for your consideration, If you are willing to participate or have any questions please contact Dr. Lazcano, Assistant Professor of Soil Ecology, Department of Land, Air and Water Resources, University of California Davis at clazcano@ucdavis.edu.

  • FDA Releases Findings Following 2020 Outbreak Linked to Central Valley Peaches

    The U.S. Food and Drug Administration (FDA) has released a report on its investigation of the Salmonella Enteritidis outbreak in Peaches. The FDA and multiple state and federal partners investigated an outbreak of Salmonella Enteritidis infections that were linked to the consumption of peaches during the summer of 2020. In total, the outbreak caused 101 reported illnesses across 17 states, including 28 hospitalizations. This appears to be the first time a Salmonella outbreak has been linked to peaches.

    The FDA conducted this investigation in conjunction with the U.S. Centers for Disease Control and Prevention (CDC), state partners, and Canadian public health officials between August and October 2020. The epidemiological and traceback investigation determined that peaches packed or supplied by a large grower/producer were the likely source of the outbreak. The traceback evidence informed and helped to prioritize two subsequent investigations of peach packing/holding operations and peach orchards in Cutler, Kerman, and Sanger, California.  The large grower/producer cooperated with FDA throughout the investigation and is continuing to engage with FDA on the agency’s findings and recommendations.

    Investigators conducted over 700 tests on environmental, peach, and peach tree leaf samples.  While no test results matched the 2020 outbreak strain, four tests conducted on peach and peach tree leaf samples collected from an orchard adjacent to a poultry operation yielded positives for Salmonella Alachua which were further linked via whole genome sequencing (WGS) to 2019 and 2020 chicken isolates. This finding prompted a follow-up investigation more closely focused on growing areas and a voluntary recall by the firm, preventing the tested, contaminated product from reaching the market. During the follow-up investigation, two tests of peach tree leaf samples collected from orchards adjacent to a cattle feedlot yielded positives for Salmonella Montevideo that were genetically similar via WGS to 2018-2020 beef and cattle isolates.

    While investigators did not find the outbreak strain, and the strains of Salmonella found during this outbreak were not linked to any clinical illnesses, the investigational findings reinforce the FDA’s concern about the potential impact that adjacent land uses can have on the safety of produce.

    The FDA views the implementation of appropriate science- and risk-based measures to reduce the potential for contamination of peaches and other produce as the most effective and practicable means to improve the safety of fresh produce, especially when measures are tailored to the specific practices and conditions on individual farms. The FDA encourages all growers to be cognizant of and assess risks that may be posed by adjacent and nearby land uses, including for the potential impact of dust exposure. The FDA also recognizes the interconnection between people, animals, plants, and their shared environment when it comes to public health outcomes, and we encourage collaboration among various groups in the broader agricultural community (e.g., produce growers, those managing animal operations, state and federal government agencies, and academia) to address this issue.

    For additional information

  • The Benefits of Environmental Monitoring

    Each year roughly 48 million people get sick, 128,000 are hospitalized, and 3,000 die from
    foodborne illnesses according to the CDC. As our food supply becomes progressively more
    globalized, the need to strengthen food safety systems in and between countries has become
    much more apparent.

    Legislation like the Food Safety Modernization Act (FSMA) now enables the Food & Drug
    Administration (FDA) to better protect consumers by strengthening food safety systems for
    foodborne illnesses, which are mostly preventable and are a significant public health burden.
    With the creation of FSMA, the FDA has become more proactive towards food safety
    prevention. One solution to the ever-growing issue of foodborne illness is the inclusion of a
    robust Environmental Monitoring Program (EMP).

    Understanding Environmental Monitoring

    According to FDA rule Verification of Implementation and Effectiveness CFR 21 section 117.165
    and the Food Safety Modernization Act (FSMA) Final Rule for Preventive Controls for Human
    Food:

    A facility who has identified a potential environmental pathogen or indicator organism
    as a hazard to ready-to-eat (RTE) foods are required to include an EMP in their food
    safety plan. A trained Preventive Controls Qualified Individual (PCQI) needs to review
    EMP test results to ensure that the Food Safety Plan is being followed.

    It is necessary for a FSMA EMP compliant Food Safety Plan to include:

    •  Established, written and scientifically valid procedures
    •  Identified testing microorganisms, adequate locations, and number of collection sites
    •  Identified timing and frequencies for collecting and testing samples
    • Identified Corrective Action Procedures in compliance with CFR 21 section 117.150
    •  Testing performed by an accredited laboratory.

    The Benefits

    The purpose of an EMP is to identify problem areas where potentially harmful microorganisms
    may be harboring, becoming a source of contamination; as well as verifying the effectiveness
    of sanitation programs. Several benefits of an EMP include:

    • Validation and verification of cleaning and sanitation programs. i.e., procedures and
      frequency
    • Provides data of the overall effectiveness of your sanitary program, personnel
      practices, and operations procedures
    • Provides data about indicator organisms, spoilage organisms, and pathogens to
      prevent outbreaks
    • Determines if facility maintenance is required, i.e., filter changes
    • Acts as a baseline microbiological assessment of a facility’s environment
    • Helps users find and eliminate potential contamination sites before it has spread

    Areas of Concern

    There are many routes environmental pathogens and other harmful organisms can be
    introduced directly into your facility. Some of these routes are by raw materials, ingredients,
    supplies, equipment, and vehicles, as well as personnel, visitors and pests. Two harmful
    pathogens to keep track of are Salmonella and Listeria.

    Salmonella

    Salmonella is a widespread and resilient bacteria that is found in the environment. It can
    survive in “dry” manufacturing environments, as well as “wet” manufacturing environments.
    Essentially, it is a versatile bacteria that has the potential to causes harm when you
    aren’t proactive.

    According to the CDC, Salmonella causes around 1 million foodborne illnesses, 19,000
    hospitalizations and 380 deaths in the United States annually.

    Not only can Salmonella result in foodborne illnesses, but it can also result in a costly recall for
    your company. FDA currently considers Salmonella to be the top environmental pathogen of
    concern in low moisture foods. Outbreaks and recalls caused by Salmonella have been linked
    to raw chicken, ground beef, pre-cut melon, and breakfast cereals. There is also a history of
    recalls in tree nuts, nut butter, alfalfa sprouts, cantaloupes, and chicken.
    Our article “Salmonella- The Most Common Bacterial Foodborne Disease” goes into detail
    about Salmonella and effective ways for you to prevent it in your facility.

    Listeria

    Listeria bacteria is prevalent in the environment. It is found in soil, water, and
    decaying vegetation. There are six types of listeria, but only Listeria
    monocytogenes (L. monocytogenes) is considered harmful to humans.

    L. monocytogenes is persistent in and around equipment and the processing
    environments in harborage sites. It can survive and grow at refrigerated
    temperatures, tolerate high salt concentrations such as a brine tank, and
    survive frozen storage for extended periods. Due to these factors, L.
    monocytogenes presents a severe food safety concern.

    According to CDC, L. monocytogenes causes about 1,600 foodborne illnesses and 260
    people deaths in the United States annually. Outbreaks and recalls are regularly linked to
    ready-to-eat RTE sliced meats, frozen vegetables, packages salads, dairy products, and
    cantaloupes.

    How to be Proactive

    To systemically combat these pathogens, a robust Environmental Monitoring Program usually
    utilizes zoning concepts. Zones are a useful tool that can help you in site selection within your
    facility. The EMP zoning concept divides risks into four zones based on the level of risk to
    product contamination with Zone 1 being the highest.

    Zone 1 – Direct or indirect Food Contact Surfaces (FCS), i.e. product conveyors, product
    chutes, storage hoppers, slicers, worktables and employee hands.

    Recommended testing for zone 1 are:

    • Aerobic Plate Count (APC)
    • Enterobacteriaceae (TEB)
    • Adenosine Triphosphate (ATP) rapid testing

    Pathogens need to be tested in special circumstances such as a response to Positive
    Salmonella product result.

    Zone 2 – Non-FCS that are adjacent to or close to zone 1, i.e., equipment supports, frames,
    control panels, weight scales, floor drains and air filters.

    Recommended organisms to be tested:

    • Salmonella spp
    • Listeria spp

    Both of these tests need to be performed weekly.

    Zone 3 – Non-FCS within process area but further
    removed from product contact surfaces in open
    product areas, i.e., forklifts, walls, floors, ceilings,
    wash stations and brooms.

    Recommended organisms to be tested:

    • Salmonella spp
    • Listeria spp

    Both of these tests need to be performed weekly.

    Zone 4 – Non-FCS outside of the processing areas,
    i.e., locker rooms, cafeteria, hallways, trash areas,
    wash stations outside of production areas and
    loading docks.

    Recommended organisms to be tested:

    •  Salmonella spp
    •  Listeria spp

    Both of these tests need to be performed weekly.

    If you find a positive environmental result in any of the zones, immediately quarantine the
    area and put affected product on hold. Next, thoroughly investigated the area both visually
    and with microbial testing.

    Understanding Vector Swabbing

    The best way to investigate a positive
    environmental result is with vector swabbing.
    Vector swabbing determines the extent of the
    contamination and to establish potential root
    causes of the contamination.

    Diagram is courtesy of the PEM Guidance on Environmental
    Monitoring, Almond Board of California

    Vector swabbing involves sampling of multiple environmental sample sites around the initial positive site in a radial patter. This approach gives you the best possible coverage of
    the environment.

    What to remember when swabbing:

    •  Vector swabbing needs to be sampled before cleaning the initial positive site.
    • Make sure the area is thoroughly cleaned and sanitized, taking great care not to
      spread the contamination to surrounding areas.
    •  Take additional environmental after the cleaning process.
    • You need to obtain three consecutive days of negative results until you can return to
      your regular EMP.

    Sampling

    After you have established your zones and your
    proposed action plan in the event of a positive environmental sample, you now need to
    samples the intended sites. Various methods can be used for collecting environmental
    samples such as sterile swabs and sponges. When collecting these types of samples, the
    surface area sampled can vary depending on the target site. An acceptable sampling area for
    indicator organisms is 40-200 in 2 and for pathogens is 40-400 in 2 .

    If the sampling collection is post sanitizer application, make sure the sterile swab and
    sponge has a neutralizing buffer. The neutralizing buffer counteracts cleaners and sanitizers
    that have been used- we want to find any surviving bacteria if they are present. Environmental
    samples are to be promptly submitted to an accredited Laboratory for testing. Ideally,
    environmental samples should be transported <45 o F and processed within 48 hours.

    Next Steps

    The cost of environmental contamination can be high, so you must ask yourself what risk you
    are willing to take? To save yourself a lot of trouble ensure you have an effective and robust
    Environmental Monitoring Program!

    With one, you can guarantee that you find any potential contamination risk and eliminate it
    before any possible cross-contamination of your product occurs. It is important to remember
    that commitment is needed throughout the facility, from senior management and cascading
    down to the rest of the workforce. Sufficient resources, both in capital and personnel to do an
    adequate job are also needed, and while the thought of creating a new EMP may seem like a
    daunting task, the outcome is not only beneficial for your facility but also to the consumer.

    Safe Food Alliance offers an online course for Environmental Monitoring to help you
    understand what Environmental Monitoring is, what the requirements for FSMA are, and other
    information to help with creating and understanding your Environmental Monitoring
    program.

  • Produce Safety Training Ensuring Continued Enjoyment Of Specialty Crops

    Davis, Calif., (January 29, 2018) – Oakleaf, Mizuna, Red Rib Chicory, Lollo Rosa, and Lamb’s Lettuce, are the names of a few of the leafy vegetables which graced my salad plate. The thinly sliced fresh red onion, juicy pomegranate kernels, and fresh citrus dressing added to the delectable ensemble. I, as well as so many other California diners, have grown accustomed to the taste-bud sensations that await us in this day of the farm-to-fork movement.

    Ronald F. Bond collecting samples in the Salinas Valley. (Photo: M. L. Partyka)

    As I inhaled my salad, I couldn’t help but think of the recent E. coli O157:H7 outbreak that affected at least 24 people in the U.S. and more than 40 in Canada. Originally it was blamed on Romaine lettuce, but early in January the CDC said in a statement that the likely source of the outbreak in the United States appears to be leafy greens. However, officials have not identified a specific type of leafy green or specifically where it originated.

    A 2013 report from the U.S. Centers for Disease Control revealed that 46 percent of all foodborne illnesses that led to hospitalization or death between 1998 and 2008 were attributable to fresh produce. The report brought to the consumers’ attention that, while fresh fruits and vegetables are the cornerstones of a healthy diet, when improperly handled, they can be fatal.

    In spite of these sobering statistics I feel confident to continue my consumption of raw produce, in part because of the knowledge of such things as the Specialty Crop Block Grant Program administered by CDFA to create and deliver educational materials for growers to assist in conducting agricultural water sampling and environmental assessments. The grant is part of an effort to help growers meet the requirements of the Food Safety Modernization Act (FSMA) Produce Safety Rule (PSR) standards for safe foods.

    Western Institute for Food Safety and Security (WIFSS) and UC Agricultural and Natural Resource (ANR) personnel – including plant pathologist Bennie Osburn, UC Cooperative Extension specialist Alda Pires, UCCE specialist Erin DiCaprio, and WIFFS staff Heather Johnson and Ronald Bond – are developing a guide for California’s mid- and small- farm specialty crop growers to meet the requirements of the PSR. Training materials, including online and face-to-face field exercises, will be developed for extension specialists and farm advisors. To facilitate the learning experience, there will be online information in multiple languages including Spanish, Hmong, Mandarin and English to meet the diverse needs of California specialty crop growers. The final step in the process will be to deliver the course materials in seven outreach workshops in those regions of California where mid- and small-sized growers are located.

    With UC Davis and UC ANR working together to support California specialty crop growers as they work to meet the new compliance standards of the FSMA PSR, we can long enjoy the abundant, fresh leafy green produce produced in California’s fertile valleys.