Water, Contaminants and Flooding - PowerPoint PPT Presentation

1 / 22
About This Presentation
Title:

Water, Contaminants and Flooding

Description:

Use potable (drinking) water for pesticide sprays. When potable water is ... Use potable water for all produce washing, cooling, dipping, icing, and processing. ... – PowerPoint PPT presentation

Number of Views:48
Avg rating:3.0/5.0
Slides: 23
Provided by: markari5
Category:

less

Transcript and Presenter's Notes

Title: Water, Contaminants and Flooding


1
Water, Contaminants and Flooding
John Strang University of Kentucky
2
  • Water destined for agricultural production can
    easily get contaminated with human and/or animal
    feces by direct or indirect routes.

3
Sources of Contamination1 Water
  • Anytime water comes in contact with fresh
    produce, the waters quality determines the
    potential for pathogen contamination, since water
    may be a carrier of a number of types of
    microorganisms.

4
Water Carries Pathogens
  • E. coli 0157H7 viewed primarily as a water-borne
    pathogen.
  • Many outbreaks associated with recreational
    water.
  • Salmonella, Giardia and Cyclospora outbreaks on
    produce caused by contaminated water.

5
Agricultural Water
  • Usually, water for agricultural uses comes from
  • Surface sources such as rivers, streams,
    irrigation ditches, ponds, and canals
  • Reservoirs (open or capped)
  • Municipal water systems

6
If you use surface water
  • Test water quarterly for fecal coliforms and keep
    records of all water test results.
  • Take a close look at where your water lies in
    relation to potential sources of contaminants.

7
Ground water may be contaminated by a variety of
biological and chemical hazards, which include
  • Bacteria and viruses
  • Domestic waste
  • Nitrate nitrogen
  • Synthetic organic chemicals
  • Heavy metals
  • Petroleum residues
  • Combustion products from roadways

8
Spray Water Quality
  • Use potable (drinking) water for pesticide
    sprays.
  • When potable water is not available, test water
    quality and keep records.
  • Low water volumes reduce risk.

9
Flooding
  • Crops in close proximity to soil can easily be
    contaminated by direct contact with flood waters.
  • FDA considers ready-to eat crops (such as leafy
    greens and melons) that have contacted flood
    water to be adulterated.
  • These crops are to be excluded from the food
    supply.

10
Flooding
  • Consider potential contamination of crops from
    agricultural run-off (i.e. manure piles, etc.)
  • Prevent cross-contamination by (equipment or
    humans) from flooded areas to non-flooded areas
  • Allow flooded soils to dry sufficiently and be
    reworked prior to planting additional crops

11
If you have any concerns about your water
  • Microbiological testing is used in the
    verification steps of a safety assurance program.
    It is important to document the frequency and
    results of each water test for comparison
    purposes. These records would become very
    important in the event of a microbiological
    outbreak investigation.

12
Recommended Draft Guidelines on Water Testing for
The Produce Industry
  • Preharvest/harvest water that contacts EDIBLE
    portions of the produce (i.e., water used
    exclusively for irrigation and/or in pesticide
    sprays for products such as lettuce and other
    leafy greens.)
  • Generic E. Coli lt235 cfu/100 ml sample of
    generic E. Coli for a single sample or lt126
    cfu/100 ml sample geometric mean.
  • Where surface water is used for irrigation,
    monthly tests are recommended minimum frequency.

Colony forming units
13
Recommended Draft Guidelines on Water Testing for
The Produce Industry
  • Preharvest/harvest water that DOES NOT contact
    edible portions of the produce (such as
    irrigation water for melons, apples, etc.) such
    as that used in drip or furrow irrigation.
  • Generic E. Coli lt576 cfu/100 ml sample of
    generic E. Coli for a single sample or lt126
    cfu/100 ml sample geometric mean.
  • Where surface water is used for irrigation,
    monthly tests are recommended minimum frequency

Colony forming units
14
Recommended Draft Guidelines on Water Testing for
The Produce Industry
  • Post Harvest Water, such as that used by
    processors or on-site sampling and cutting
    /processing.
  • Water must meet standards for potable (drinking)
    water.

Note The Ky. public beach microbial standard is
130 cfu generic E. Coli/100ml sample on a single
sample.
15
If Tests of Preharvest/Harvest Water are Found
to Exceed Recommendations
  • Consider an alternative water source.
  • Investigate what is causing the elevated
    microbial counts.
  • Have irrigated crops tested for common human
    pathogens (E. Coli, salmonella etc.).

16
Water Source Will Determine the Possible
Frequency of Testing
17
Chlorine required to dose 100 ft (30 meters) of
water-filled casing at 50 mg/L (ppm)
1 Commercial brands include HTH,
Perchloron, Pittchlor, etc. 2 Commercial
house hold bleaches such as Chlorox, Purex, etc.
18
Chlorination
  • Everything that is harvested does not need to be
    sanitized or chlorinated!
  • The need depends on how the produce will be
    marketed.

19
Postharvest Processing Water
Singular critical control point capable of
amplifying an error in sanitation or hygiene
management
Suslow, UC Davis
20
The Problem with Water Handling Systems
  • Produce from the field usually harbors many
    pathogens (including dirty and decaying produce).
  • Postharvest handling of fruits vegetables often
    includes cooling using water and washing.
  • Pathogens can quickly accumulate in these water
    sources and contaminate healthy fruit.

21
Wash Water Quality
  • Use potable water for all produce washing,
    cooling, dipping, icing, and processing.
  • Avoid water temperatures in dump tanks that are
    more than 10F cooler than produce.

22
Bacteria can enter the stem scar with improper
handling or wash water management
Fruit pulp must be lt 10oF warmer than water
temperature to prevent infiltration.
Warm fruit contracts in cold water pulling water
and microbes into the fruit.
Write a Comment
User Comments (0)
About PowerShow.com