Food Safety 2 - UCANRmgeldorado.ucanr.edu/files/160224.pdf · 2013. 1. 29. · is critical. There are a number of potential water sources for garden irrigation. A municipal water

1

1/26/2013

El Dorado County Master Gardeners Edible Landsccaping Workshop

Food SafetyBy Phyllis Lee

Share expectations when you purchase food.. -Food is fresh and safe-Grown in a wholesome environment (safe clean location)-Produced using safe practices (sanitary fertilizers)-Harvested hygienically (clean hands/tools)-Stored under sanitary conditions

Fruit Baskets: Photo used under Creative Commons Attribution license by Natalie Maynor. Derivative work by S. YamamotoFarmers Market: Photo used under Creative Commons Attribution license by haansgruber.Vegetabel photo: Photo used under Creative Commons Attribution license by USDA

2

1/26/2013



After food sources come into contact with pathogens it’s virtually impossible to remove the pathogen (if eaten raw). To prevent contamination evaluate as you plan your garden, during the growing period, and at harvest.

Snap pea/pansy, and chicken photo by Sheryl Yamamoto

3

1/26/2013



Growing plants purely for aesthetic enjoyment can be vastly different than growing plants that provide us with food. An edible landscape is not only aesthetically pleasing, but it must be capable of producing SAFE food.

Romanesco: Photo used under Creative Commons Attribution license by Nick Saltmarsh. Derivative work by S. YamamotoCherry Blossom: Photo used under Creative Commons Attribution license by Lance Cheung. Derivative work by S. YamamotoChives and Pansy Peas by S. Yamamoto

4

1/26/2013



The most common sources of outbreaks are in part related to those items that are both most commonly consumed (volume) AND commonly consumed RAW (without cooking).

Produce-related outbreaks are often linked to poor worker hygiene, inadequate water quality, use of contaminated soil amendments (such as raw manure) and the presence animals infected with the implicated pathogen.

Figure: Source FDA/CFSAN 2011E. Coli O157:H7: NIAIDSalmonella spp.: NIAIDListeria monocytogenes: Wikimedia Commons, derivative work by Sheryl YamamotoHepatitis A virus: Image 2739 CDC, derivative work by Sheryl Yamamoto

5

1/26/2013



As a result of the recent history of outbreaks and several high impact outbreaks, the use of Good Agricultural Practices has become an essential component of doing business on commercial farms. The guidelines focus on risk factors and have a strong emphasis on preventing food safety-related issues from the planning stage of the farm through distribution of the produce. Prevention is KEY. It is generally accepted that once the produce is contaminated, it is exceptionally difficult to remove or kill the pathogens present on the fruit or vegetable if that product is eaten fresh. Knowing the risks and mitigating those risks up front is the most effective method for being able to enjoy safe produce.

Foodborne pathogens are excreted in the feces of animals and humans. Therefore, there are 4 main source of foodborne pathogens in the garden: water (when contaminated), animals, soil amendments, and people. Good practices reduce the risk of contamination. We will address these in more detail later in the presentation.

6

1/26/2013



When choosing a site for any type of edible landscape, it is important to know the history of the land. This is particularly important for community gardens but may also be an issue in the home garden. Was there prior land use that could have left chemical, physical, or microbiological hazards lingering on the site? Were cattle or foul previously farmed on the land? Did chemicals unintentionally contaminate the site?

Particularly for community gardens: Who are your neighbors? What are they doing now and how do they plan to use the land in the future? What type of zoning exists? What will they build next to the property line next year?

Take a look at the integrity of the existing structures on the property. Where are the sewage line? Is there a septic system and where is it located? How will you be delivering water to the landscape? Are the waterlines clean? These are some of the issues to be considered before deciding on a site for your edible garden.

Photo used under Creative Commons Attribution license by Rick Bradley. Derivative work by S. Yamamoto

7

1/26/2013



In the edible landscape, water will be used to irrigate the plants, and possibly for hand washing stations.Water can quickly and efficiently transfer contaminants to produce so knowing that a water source is clean is critical. There are a number of potential water sources for garden irrigation.

A municipal water system would be considered safe. Wells are an acceptable source of water but they should be tested for contamination on a regular basis. Examine design and current integrity of the well and make sure that it was designed to avoid surface run off or soil infiltration. The quality of surface water (lakes, streams) can change throughout the season and should not be a regular source of irrigation for edible plants. Rainwater collected and stored correctly should be acceptable to use but carries a greater risk than municipal water. Risk may come from a storage container and include both microbial and chemical risks.Greywater is wastewater from baths, showers, clothes washers, and bathroom sinks. Greywater is a potential source of human pathogens. Many counties do not allow.

Well Water: Photo used under Creative Commons Attribution license by Don O Brian Attribution derivative work by S. Yamamoto Municipal Water: Photo used under Creative Commons Attribution license by Austin Marshall derivative work by S. YamamotoSurface water and Greywater: S. Yamamoto

8

1/26/2013



Rainwater Collection Bucket: : Photo used under Creative Commons Attribution license by Katie Elzer-Petersderivative work by S. Yamamoto

1/26/2013

8


El Dorado County Master Gardeners Edible Landscaping Workshop

The greatest risk for foodborne illness occurs when the edible portion of the crop is contaminated close to the harvest date. This includes plants that yield fruit with peels that may not be consumed (melons, citrus).

Lower your risk by irrigating with potable water where the contact is direct and close to harvest. Use drip or trickle methods of irrigation when water quality is unknown or of lower quality (e.g., surface water, rainwater, or greywater) but make sure these systems are maintained – that they do not leak or cause water to pool. Water that is known to be microbiologically safe (such as clean municipal or tested well water) is not likely to introduce microbiological contamination to the plant. However, dirty pipes or hoses, may result in contamination of water that is clean leaving the tap.

Water on Leaf: Photo from Wikimedia by KkongGarden Water: Photo used under Creative Commons Attribution-NoDerivs license by USDADrip system: Photo used under Creative Commons Attribution-Share Alike license by JISL

9

1/26/2013



Use of properly composted manures is strongly recommended over the use of raw manures. Animal manure as well as human sewage must be properly composted. Manure from pigs, dogs, cats, or humans must not be used as parasites may remain viable after composting.

Domestic green manure is made from plant matter that is grown and chopped before applying to the soil. It does not contain animal manure and does not need to be composted to be used safely.

Photo by S. Yamamoto

10

1/26/2013



Input from audience -Domestic and wild animals can be significant sources of microbial contamination. Direct fecal contact, waste water runoff, or wind can cause pathogens to contact the edible plant.

Cat: Kristine YamamotoCat feces: Linda HarrisDuck, chicken, cattle, frog: Sheryl YamamotoDeer: Used under Creative Commons Attribution-No Derivative works license by USDAHarvest mouse: Used under Creative Commons Attribution license by Neil McIntoshChicken droppings: Used under Creative Commons Attribution license by fishermansdaughter)

11

1/26/2013



The presence of any domestic animals in the garden should be carefully considered. Ducks and geese might seem like “natural” ways to achieve pest control but are they necessary? Should the family dog (who loves to hunt rats and roll in the neighbors manure pile) be allowed free reign in the garden? Where should the chicken coop be located – or is it mobile and how does that impact the garden? Wild and domestic animals can be asymptomatic carriers of a variety of pathogenic bacteria, viruses, and parasites (Salmonella, E. coli O157:H7, Cryptosporidium, Toxoplasma).

If it is necessary to keep domestic animals near the garden, efforts should be made to minimize or restrict their access to edible plants. Have a plan for managing and containing animal waste. Runoff from fecal deposits could spread disease in an edible landscape.

Photo used under Creative Commons Attribution-No Derivative works license by Hardworking Hippy

12

1/26/2013



Growing season and harvestWhat we do and what we use in the garden needs to be rethought for the edible landscape. Those trowels, buckets, watering cans, hoses, and clippers that are used for the ornamental landscape might harbor pathogens or chemicals that can contaminate food surfaces. You might use one set of tools for the ornamentals and one for the edible plants. The edible plant tools need to be stored in an area where animals can’t contaminate their surfaces, molds can’t grow, and chemicals that aren’t safe for consumption aren’t used. Are their surfaces cleanable and if needed can they be sterilized? Additionally, what water source will be used to mix fertilizers? Choices at this stage can help keep your food safe for consumption.

13

1/26/2013



Consider designating tools or protective equipment to either “clean” or “dirty” jobs in the garden to prevent cross-contamination of microbial and chemical hazards to edible plants. For example, one set of tools can be used for working with or applying compost while another can be used for working around edible plants. Designate one pair of gloves for pesticide application while another pair can be designated for pruning or harvesting edible plants. Alternatively, disposable latex or nitrile gloves may be used for working with compost or chemicals and simply discarded when the work is finished. If the disposable gloves are worn under normal gardening gloves, be sure to launder the gardening gloves.

Tools and protective items used during harvest such as clippers, buckets, or gloves should be cleaned and sanitized before use. Clippers can be placed in the dishwasher while fabric gloves and other protective clothing can be laundered. Clean surfaces directly in contact with food including tabletops, workbenches, containers and bins by first washing with warm soapy water and then rinsing with a sanitizing solution such as bleach (1 tablespoon household bleach per gallon of water).

Exclude and discourage vectors (insects, rodents, birds, etc) from the workspace or storage area. Discard old/damaged fruit and clean surfaces of food residue.

Workbench: Used under Creative Commons Attribution license by Andrea44

14

1/26/2013



Photo used under Creative Commons Attribution-Non Commercial license by Peregrine Blue

15

1/26/2013



Documents

Food Safety 2 - UCANRmgeldorado.ucanr.edu/files/160224.pdf · 2013. 1. 29. · is critical. There are a number of potential water sources for garden irrigation. A municipal water