July 1, 2016
Irrigation of fruit, vegetable crops is food safety matter
WEST LAFAYETTE, Ind. - Indiana fruit and vegetable growers bringing irrigation systems into operation as production gets into full swing should have their water tested as part of good agricultural practices for produce food safety, Purdue Extension food safety educator Scott Monroe says.
Testing water is one of the most important things growers can do to minimize the risk of microbial contamination in growing crops, Monroe said. Water is used for multiple operations in fruit and vegetable production, making it a potential medium of transfer for foodborne illness.
“We use water for irrigation, pesticide application, frost protection and washing and packing, and many other uses,” he said. “The amount of uses and the potential for carrying human pathogens makes water a major food safety focus.”
Growers who meet certain criteria under the Food and Drug Administration’s Food Safety Modernization Act Produce Rule, which took effect in January, must test water that is applied to harvestable portions of growing crops. Monroe noted that the new regulations require frequent testing over two years to establish a baseline, with periodic testing required thereafter.
While some growers may be required by the produce rule to do extensive testing, Monroe said it is a good idea for all produce growers to test their water.
The frequency of testing is determined by the water source. Surface water is generally unprotected and carries a greater risk for contamination.
“Consequently, growers using surface water instead of underground water need to have water tested more frequently,” Monroe said.
Growers using municipal water do not need to have their water tested because the utilities are legally required to do that.
All water used for fruit and vegetable production and postharvest processing should be tested for generic E. coli, Monroe said. Generic E. coli testing will indicate potential presence of disease-causing organisms.
“If E. coli is present in a water sample, it means that the water source has fecal contamination and may, by association, harbor human pathogens,” he said.
Water samples can be submitted to any certified lab for testing. Monroe said it is important to make sure samples are sent to a certified lab.
“Always communicate with the lab to make sure they understand what the water is being used for and what test is required,” he said.
Interpreting lab results is also very important. Monroe said water used for production should not exceed 126 cfu/100 ml generic E. coli.
Water used for postharvest operations must not contain any detectable generic E. coli. If water exceeds allowable limits, growers will need to treat it or find another water source.
“While a bad test will not put a grower out of business, it does indicate a risk factor that needs to be dealt with and mitigated,” Monroe said.
Produce growers who have food safety questions concerning water use and testing can contact Monroe at the Southwest Purdue Agricultural Center at 812-886-0198 or by email at firstname.lastname@example.org.
With the 2016 growing season upon us, many produce growers will soon be collecting water samples from irrigation and postharvest water sources for microbiological analysis. Using proper techniques to collect water samples will help to prevent inaccurate testing results.
When collecting water samples, one should start with the appropriate collection container. Many laboratories will only test water samples that are received in their containers. Consequently, it is important to select a lab, determine their individual requirements, and obtain the appropriate containers prior to collecting samples. Generally, containers used for water sampling will be large enough to hold at least 100 ml of water. The interior should be sterile and the container should be sealed to prevent contamination. Sampling containers may also contain crystals or tablets when received from the lab. These tablets or crystals are made of sodium thiosulfate and are place in the container to neutralize any chlorine that may be in the water sample. They should not be removed.
If irrigation water from a well is being sampled, it is a good idea to collect the sample as close to the water source as possible. This means collecting the sample from the outlet that is closest to the well. Prior to collecting, the rim of the outlet (valve, spigot, etc.) should be sanitized. This can be done using a flame or chlorine. The system should then be allowed to run and water should be allowed to flow out of the outlet long enough to flush the system. A good rule of thumb is to run the system at least 3-5 minutes longer than is necessary to empty the volume of stagnate water remaining from the last use. To collect the sample, the seal on the sample container should be removed or broken and the sample container should be opened only as far as needed to collect the sample. Containers should be filled at least to the fill line and should be closed as quickly as possible. Once the sample is collected, the container should be marked with the date and time of collection and immediately cooled. Samples should be kept as cool as possible by icing or refrigerating until they are delivered to the lab. Many labs have a maximum time interval between collection and sample receipt, usually 24 hours. Samples received too long after collection will not be processed. Those growers who are covered under the Food Safety Modernization Act Produce Rule should pay special attention to time requirements, as the rule specifies EPA Method #1603, which only allows a maximum of 8 hours from sample collection to processing.
If sampling from surface water, such as ponds and lakes, one should try to sample at a depth of 6-12 inches. The container should be submerged prior to opening the lid. The container should then be filled and the lid put back in place prior to removing it from the water. If a dock or other structure is not available for access to deeper water, one can attach a sample container to a pole. Care should be taken not to sample too close to the bottom, as sediments may be collected with the sample. If one finds it necessary walk into the water, sampling should be done ahead of the muddy front that is stirred up by motion. Remember that excess rainfall can also stir up bottom sediments and alter test results. Samples should not be taken immediately after rainfall. Best practice is to collect the sample during a time when the water would normally be used for irrigating. If irrigating from flowing surface water, such as a creek or stream, and it is necessary to wade into the water, be sure to sample from the upstream side, again to avoid collecting stirred up sediments.
Collecting samples of water used for postharvest is similar to collection from an irrigation well. One should select an outlet close to where water lines come into the packing facility. All attachments such as aerators or garden hoses should be removed. The outside rim of the outlet should then be sanitized and water should run through the outlet for 3-5 minutes. The sample container may then be filled, taking care to make sure that the container is open for as little time as possible.
In many cases, unexpected results from a water test can be traced back to poor or inappropriate collection techniques. Details such as not flushing the system, failing to remove attachments, and sampling too near the bottom of surface water can drastically alter water test results. Taking some time to practice proper collection techniques prior to the upcoming season will help to ensure that your water test results are as accurate as possible.
In January 2016, Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption, otherwise known as the Produce Rule, became law. This rule, as part of the Food Safety and Modernization Act, sets a standard for produce food safety. The water testing component of the produce rule requires growers to regularly test irrigation water. While a previous article dealt with water testing requirements, I’ve received questions as to exactly who is required to test water. As a result, I wanted to review the steps in determining whether or not one is held to the water testing requirement.
The first step is to determine if you are covered by the produce rule. An excellent flowchart to help determine coverage may be found at http://www.fda.gov/downloads/Food/GuidanceRegulation/FSMA/UCM472499.pdf. If you’re gross produce sales averaged $25,000 or less in the last three years or you are growing produce for your own personal consumption only, then your farm is not covered by the rule and is not subject to water testing requirements. If your gross sales for the last three years average $500,000 or less and a majority of your food sales are to a qualified end-user, then you may receive a qualified exemption and will not be held to the water testing requirements in the rule. A qualified end-user is defined as the consumer of the food or a restaurant or retail food establishment that is located in the same state or same Indian reservation as the farm that produced the food or not more than 275 miles from where the food was produced.
If your farm is covered by the rule, then the next step is to determine whether or not your produce is covered by the rule. FDA has established a list of commodities that have been identified as rarely consumed raw. Many of these commodities are grown in Indiana, such as pumpkins, sweet corn, and potatoes. Commodities identified as rarely consumed raw are not covered by the rule. Also, produce grown for processing receives a qualified exemption from the rule, provided that certain documentation requirements are met. Produce destined for a processor must be accompanied with documentation that identifies the crop as not having been processed adequately to reduce the presence of microorganisms of public health significance. Additionally, growers will need to obtain documentation annually from processors that demonstrates that their crops are, upon delivery, processed adequately to reduce the presence of microorganisms of public health significance.
If you determine that your farm and particular crop are covered by the rule, Section 112.41 of the rule states that, “All agricultural water must be safe and of adequate sanitary quality for its intended use”. In following sections, the rule outlines the requirements for testing agricultural water, maintaining delivery systems, and the treating of agricultural water that does not meet standards.
The term “Agricultural Water” adds yet another layer of complexity. This term is defined earlier in the rule in Section 112.3(c) as, “water used in covered activities on covered produce where
water is intended to, or is likely to, contact covered produce or food contact surfaces, including
water used in growing activities (including irrigation water applied using direct water application
methods, water used for preparing crop sprays, and water used for growing sprouts) and in
harvesting, packing, and holding activities (including water used for washing or cooling
harvested produce and water used for preventing dehydration of covered produce).”
Note that the definition of agricultural water covers water applied using “direct water application methods”. This term is also defined in Section 112.3(c), which says, “Direct water application method means using agricultural water in a manner whereby the water is intended to, or is likely to, contact covered produce or food contact surfaces during use of the water.” For purposes of the rule, the term “produce” also has a specific, and fairly lengthy, definition given in Section 112.3(c). Produce is defined, in part, as the harvestable part of a crop.
What do all of these definitions mean? Taken as a whole, it actually simplifies the process of determining when activities and crops are covered by the water testing requirements. Instead of differentiating between irrigation methods or other qualifiers, crops are covered by water testing requirements any time water is directly applied to the harvestable portion of the crop, either as irrigation or crop sprays.
In summary, these are the questions to ask in determining when crops are covered by the water testing requirement:
1. Is my farm covered by the produce rule?
2. Is this particular crop covered by the produce rule?
3. Will I be applying water, as irrigation or crop sprays, to the harvestable part of the crop?
If you can answer “yes” to all three questions, then in your particular situation you are covered under the water testing requirements of the produce rule.
If you have any questions regarding FSMA Produce Rule coverage, please feel free to contact me at 812-886-0198 or email@example.com
The Food Safety Modernization Act Produce Rule addresses many issues with regard produce food safety. One issue not addressed is the issue of biological soil amendments of animal origin (i.e. manure). When issuing the rule, the Food and Drug Administration (FDA) chose to leave blank those portions of the rule dealing with the required interval between manure application and harvest of covered crops pending a comprehensive risk assessment by the agency.
FDA has initiated its comprehensive risk assessment process by publishing a request for scientific data, information, and comments in the Federal Register on March 4. There will, most likely, be other requests for comments as FDA investigates the issue and incorporates its findings into the produce rule.
In January 2016, Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption, otherwise known as the Produce Rule, became law. This rule, as part of the Food Safety and Modernization Act, sets a standard for produce food safety. Not all growers are covered by the rule. An excellent flowchart to help determine coverage may be found at http://www.fda.gov/downloads/Food/GuidanceRegulation/FSMA/UCM472499.pdf. For those growers who are covered by the rule, there is a training requirement. Growers will have from 2-4 years, depending on farm size (defined by gross sales), to comply with training requirements.
The general requirement of the produce rule is that all personnel who handle covered produce (i.e. commodities covered under the rule) or food contact surfaces or are engaged in supervision of those personnel must receive adequate training, appropriate to the person’s duties, upon hiring and at least once annually thereafter. The rule goes on to say that personnel must have a combination of education, training, and experience necessary to perform their assigned duties in a manner that assures compliance with the rule. Training must be conducted in a manner that is easily understood by personnel being trained. The rule also requires that training be repeated as necessary and appropriate in light of observations or information indicating that personnel are not meeting standards established by the rule.
At a minimum, training should include:
1. Principles of food hygiene and food safety.
2. The importance of health and personal hygiene for all personnel and visitors, including the recognition of symptoms of a health condition that is reasonably likely to result in contamination of produce or food contact surfaces.
3. Standards established in the produce rule that are applicable to the employee’s job responsibilities.
Additionally, for those workers who are involved in harvest activities, training should include:
1. Recognition of produce that should not be harvested due to potential contamination with known or reasonably foreseeable hazards.
2. Inspection of harvest containers and equipment to ensure proper function and cleanliness.
3. Correction and reporting of problems with harvest containers and equipment.
Also, at least one supervisor or responsible party per farm must have successfully completed food safety training at least equivalent to that received under the standardized curriculum recognized as adequate by the FDA. The standardized curriculum has been developed by the Produce Safety Alliance (PSA). Presently, as stated in the produce rule, FDA intends that the PSA curriculum will be the only curriculum officially recognized by FDA. The rule does allow for other curricula to be used as long as it is equivalent to the PSA curriculum. Presently, no mechanism exists to assure the equivalency of other curricula to the officially recognized curriculum.
Currently, PSA has delayed all training programs until September 2016. This was done in order to allow FDA time to review the official curriculum. Once training begins, training for those who are delivering the curriculum will commence. In Indiana, at least eight individuals have started the process of becoming certified lead trainers who are able to offer this curriculum on a statewide basis. Once PSA resumes trainings, certifications will be completed and trainings will be offered shortly thereafter.
As stated previously, each covered farm will need to have at least one supervisor or responsible party complete training. The rule does not take into account any previous trainings that growers may have had. Based on the most current information that I have, trainings will be managed through the Association of Food and Drug Officials (AFDO). Pricing will be $50 for registration and materials and $35 for a certificate at the conclusion of the training.
As we gear up for the 2016 season, please feel free to contact me at (812) 886-0198 or firstname.lastname@example.org if you have any questions concerning food safety training. I am available to discuss training issues and to assist with any on-farm training needs that you may have.
In January 2016, Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human Consumption, otherwise known as the Produce Rule, became law. This rule, as part of the Food Safety and Modernization Act, sets a standard for produce food safety. Not all growers are covered by the rule. An excellent flowchart to help determine coverage may be found at http://www.fda.gov/downloads/Food/GuidanceRegulation/FSMA/UCM472499.pdf. Those growers who are covered by the rule will have from 2-4 years, depending on farm size (defined by gross sales), to be in compliance. All growers will then receive an additional 2 years to comply with the water testing component of the rule.
The water testing component of the produce rule requires growers to regularly test irrigation water. Growers irrigating with surface water (ponds, lakes, streams, ditches) are required to collect and test 20 samples over a two-year period in order to establish a baseline. Once the baseline is established, 5 samples must be collected and tested every year thereafter. Growers using underground water sources (i.e. wells) will be required to initially collect and test 5 samples over a one-year period in order to establish a baseline. Once the baseline is established, below ground water sources will need to be tested once annually.
When writing the produce rule, the Food and Drug Administration (FDA) chose to use generic E. coli as an indicator of water quality. Indicators, while not human pathogens, are used to indicate the potential for contamination with a human pathogen. The reasoning is that if the indicator organisms are present, there is a reasonable likelihood that human pathogens may also be present. As a result, water samples collected by growers who are covered by the produce rule will need to be tested for generic E. coli, in addition to any other tests the grower may require.
For all irrigation water, the geometric mean of sample results cannot exceed 126 colony forming units (CFU) of generic E. coli per 100 ml of water. Additionally, the statistical threshold value cannot exceed 410 CFU generic E. coli per 100 ml. In the case of surface water, the initial 20 samples will be used to confirm that the irrigation water meets quality standards. After baseline establishment, growers will use the most current year’s test results (5 samples) and the 15 most recent test results from previous years to create a rolling dataset of 20 test results from which new threshold calculations are performed annually. In the case of irrigation water from below-ground sources, an initial 4 samples will be used to confirm that the irrigation water meets quality standards. After baseline establishment, growers will use the previous year’s test results (1 sample) and the 3 most recent test results to create a rolling dataset of 4 test results from which new threshold calculations are performed annually.
This standard applies to all water applied to the crop prior to harvest. In writing the produce rule, FDA chose not to differentiate between methods of irrigation. Consequently, the water testing requirement and thresholds apply whether growers utilize drip or overhead irrigation. In cases where growers’ test results exceed the thresholds, the issue must be addressed and corrected. Growers have the following options:
1. Allowing time for microbial die-off in the field between irrigation and harvest. Growers may assume a 0.5 log reduction per day in microbe levels.
2. Treating the water or water source with an approved sanitizer
3. Finding an alternative water source that meets requirements.
Water used for postharvest must be potable, which means no detectable generic E. coli. It is the responsibility of each farm to be able to demonstrate that their postharvest water meets this quality standard. In the case of farms using well water for packing lines or for other postharvest uses, they will need to document that the water is of sufficient quality by having the well tested in accordance with the procedures for underground water. This means collecting an initial four samples over a one-year period, establishing a baseline, and then testing one sample annually. Growers who are using well water for postharvest are advised to begin this process as early as possible in the growing season in order to establish their baseline prior to this season’s harvest. In establishing the baseline, tests from last season may be used, as long as all the tests are taken within a one year period.
Please feel free to contact me at 812-886-0198 or email@example.com should you have any questions about water testing or any other components of the produce rule.
In November 2015 the Food and Drug Administration (FDA) published the final version of Standards for the Growing, Harvesting, Packing, and Holding of Produce for Human
Consumption, otherwise known as the Produce Rule, in the Federal Register. Sixty days later, in January 2016, the rule became law. The Produce Rule is one of several new regulations mandated by the Food Safety Modernization Act (FSMA), which was signed into law in January 2011.
1. What is the value of my produce sales? Growers whose produce sales have averaged $25,000 or less for the past three years are not covered by this rule.
2. What crops am I growing? FDA has listed several crops that are rarely consumed raw. Examples of these crops are winter squash and potatoes. These crops are exempt from coverage.
3. What is the value of all my food sales? Growers whose total food sales (including agronomic crops and livestock) have averaged $500,000 or less over the past three years may receive a qualified exemption.
4. How am I marketing my crops? In order to receive a qualified exemption, over one-half of food sales must be to a qualified end user, defined as the end consumer or a restaurant or retail food establishment located in the same state or the same Indiana reservation that produced the food or not more than 275 miles from the farm that produced the food.
5. Am I producing any crops for personal consumption? Crops grown for personal consumption (i.e. not for sale into the public food supply) are not covered by the Produce Rule
6. Am I producing crops for processing? Crops grown for processing receive a qualified exemption, although certain conditions must be met to insure that crops are, in fact, being processed in a manner that adequately reduces pathogens.
Growers should remember that regardless of whether or not they are covered by the Produce Rule, there is never an exemption from liability. All growers who sell produce into the public food supply face the same liability, regardless of Produce Rule coverage, should the unthinkable happen and a foodborne illness outbreak is traced to their farm. As a result, all growers are reminded to use Good Agricultural Practices in the upcoming season as a means of reducing the risk of a foodborne pathogens contaminating produce on their farm.
Purdue University is pleased to offer Indiana fruit and vegetable farmers a farm walk-through with a private food safety consultant. This opportunity is open to any farm that sells fresh produce and has attended a produce safety educational program. A consultant paid by Purdue will visit your farm to walk through and address your specific farm and packinghouse food safety questions. Growers who participated in the consulting program in 2015 reported it was very helpful. Funds for the consulting come from a grant from the Indiana State Department of Agriculture through the USDA Specialty Crops Block Grant Program.
The grant also includes funds for audit cost-sharing for Indiana fruit and vegetable growers who receive passing scores on their third party food safety audits. The audit cost-share program will reimburse at least 40% of the cost of a third party food safety audit, up to a maximum reimbursement of $750 per farm.
To apply for consulting or audit cost-share, fill out and return the application by May 1, 2016. Applications may be downloaded from ag.purdue.edu/hla/foodsafety/Documents/PurdueFoodSafetyCostshareConsultApp2016.pdf, or applicants may fill out the online form at tinyurl.com/fs-cost-share-2016.
In addition to these programs, Purdue food safety Extension experts Amanda Deering and Scott Monroe are available to conduct mock-audits for produce farms on request. Contact Scott at 812-886-0198 at Amanda at 765-494-0512.
For more information contact Liz Maynard at 219-548-3674 or firstname.lastname@example.org.
There are certain questions within our culture for which there are simply no good answers. For example, how many times have we heard the classic question, “If a tree falls in a woods and there’s no one to hear it, does it still make a sound?” One question I’ve been asked recently, for which the answer is equally elusive, is “How long must I wait to grow vegetables after applying manure to the field?” With the 2015 season quickly winding down, it will soon be time to start making plans for next year’s crops. Part of those plans will undoubtedly include the question of manure use.
While manure is a good source of plant nutrients and organic matter, it may also contain human pathogens that can be transferred onto fresh fruits and vegetables. After manure is applied to a field, the bacterial community in the manure changes as it adapts to conditions in the soil. Given all the variables involved, exactly what happens to the bacteria is anyone’s guess. Soil type, manure type, soil moisture levels, and temperature all play a role in how quickly manure degrades and the bacterial community changes. While research is starting to shed some light on the issue, the fate of human pathogens in manure applied to the soil is still poorly understood. This was noted by FDA in their latest draft of the Proposed Rule for Produce Safety. Publications supplemental to the proposed rule stated that:
“The agency is deferring its decision on an appropriate time interval [between manure application and crop harvest] until it pursues certain actions. These include conducting a risk assessment and extensive research to strengthen scientific support for any future proposal, working with the U.S. Department of Agriculture and other stakeholders.” (FSMA Proposed Rule for Produce Safety: http://www.fda.gov/Food/GuidanceRegulation/FSMA/ucm334114.htm)
The National Organic Program specifies an interval of 120 days between the application of raw manure and harvest for crops that come in contact with the soil and an interval of 90 days for crops that do not come in contact with the soil. These serve as good general guidelines, but the intervals were not developed to assure food safety.
Remember, in addition to any general guidelines, always follow the guidance given by your particular audit protocol or food safety plan.
Those using properly composted manure may apply it at any time, taking care to avoid application to the edible parts of the plants. Those producing crops with edible parts underground may also want to avoid applying composted manure while crops are in the field. Proper composting in this context involves a high-temperature process that kills most human pathogens. The high temperatures must be documented, along with other details of the composting process. A summary of what is involved in producing compost may be found at: http://content.ces.ncsu.edu/compost-production-and-use-in-sustainable-farming-systems.pdf.
Unless you have documentation that manure was composted properly, it should be treated as nothing more than aged raw manure, and there should be an interval of several months between application and harvest of a fruit or vegetable crop.
In addition to composting, other heat and chemical treatments can reduce pathogens in manure. Often manure treated with these methods is sold commercially as a bagged or bulk product. Growers using such products should get information about the manure treatment from the supplier, and ask specifically whether the treatment is documented to kill human pathogens.
One of the best ways to utilize manure is to apply it in the fall. A fall application, followed by incorporation and a cover crop, is a good way to insure a lengthy application-to-harvest window. One additional advantage is that fall-applying manure cuts one more job from what is, for most people, an increasingly hectic spring season. For those wishing to use a fall manure application, Purdue’s Midwest Cover Crops Field Guide (ID-433, https://mdc.itap.purdue.edu/item.asp?Item_Number=ID-433) can provide valuable cover crop information. Purdue’s Manure Management Planner, although designed for field crops, can help with estimating nutrient content from various manures (http://www.purdue.edu/agsoftware/mmp/).
An additional option may be to simply use manure only on agronomic crops. As a whole, the Midwest is a very strong agronomic region. Corn and soybeans are still the main crops. Where possible, growers can use this to their advantage by applying manure to agronomic crops in the year before fields are rotated into vegetables. This gives an interval of a year or more and growers can still reap some benefits (increased organic matter, plant nutrients, etc.) from the manure application, with reduced risk to their vegetable crops.
If you must apply manure in the spring, avoid planting short-season crops in fields that have received an application. Long season vegetables, such as staked tomatoes, whose edible parts do not contact the ground, carry the least risk of being contaminated with a foodborne pathogen. Other options would be to grow late-season crops that normally are not consumed, such as pumpkins or gourds. Yet another option would be crops that are cooked prior to eating, such as sweet corn.
Across the state, growers have worked hard to incorporate food safety into the culture of their farms. Paying attention to how and when manure is applied is a good way to reduce the risk of a future outbreak.
Recently the USDA announced the addition of a new third-party auditing service that will be available through the Ag Marketing Service (AMS). The service, called “GroupGAP”, will be available in the spring of 2016. The expansion of the service follows multi-year piloting and testing of the program.
Under the GroupGAP program, independent farms may organize under a central entity, such as a food hub or grower cooperative, to create a food safety system. Participating farms are responsible for collectively developing food safety practices and collecting required documentation. Entities will also be responsible for providing their own internal auditing services. They will also participate in an external audit by USDA-AMS Specialty Crops Inspection Service.