Appendix I: Water reclaimed from the condensing of milk and milk products

Condensed water from milk evaporators and water reclaimed from milk and milk products that are re-used within the establishment must not jeopardize the safety of the product through the introduction of chemical, microbiological or physical hazards. Appropriate uses of this water fall into three categories described below.

Category 1: Reclaimed water used for potable water purposes, including the production of culinary steam.

  1. Monitor and control water to ensure it is safe and suitable for use
    • sample water daily for two weeks following initial installation of the system
    • sample water daily for one week following any repairs or alterations to the system
  2. Test water monthly to ensure it meets the following criteria, using acceptable test methodology
    • water is considered microbiologically safe if the maximum acceptable concentration (MAC) for total coliform and E. coli is non-detectable per 100 ml water sample
    • verify the heterotrophic plate count (standard plate count) does not exceed 500 cfu/ml
    • verify the standard turbidity is less than 5 nephelometric turbidity units (NTU)
  3. Assess the water weekly for off-odours and appearance (clarity, colour)
    • verify the water does not impart any off-taste and off-odours
    • verify the water does not feel or appear slimy
  4. Where water treatment chemicals are used:
    • ensure they are safe and suitable for use in dairy processing establishments
    • use an automatic metering device, prior to the water entering the storage tank, to assure satisfactory water quality in the storage tank at all times
    • test chemical addition twice a day
    • ensure they do not pose a contamination risk to the water or the product
  5. Have procedures in place in the event that the water exceeds safety standards and poses a microbiological and chemical risk
    • for example, install an automatic fail-safe monitoring device so that the water is automatically diverted to the sewer if the water exceeds the standards
  6. Water storage system design:
    • ensure storage facilities are designed, constructed and maintained to prevent contamination
      • for example, cover, construct out of materials that will not contaminate the water, and allow for periodic cleaning and sanitizing
        • use approved materials such as those from the Canadian Water and Wastewater Association (CWWA) or materials for such use as per manufacturer's guidelines
    • ensure the distribution system, within the establishment, is a separate system with no cross-connections to a municipal or private water system
  7. Without proper design, operation, and maintenance, stored water may easily become stagnant and subject to loss of chlorine residual, as well as bacterial regrowth, contaminant entry, and a host of other water quality problems.

Category 2: Reclaimed water used for limited purposes including production of culinary steam, pre-rinsing of the product surfaces where pre-rinses will not be used in food products, cleaning solution make-up water.

For these uses, in addition to items 3 to 6 above:

  1. Test water monthly to ensure the standard turbidity is less than 5 NTU
  2. Ensure there is no carry-over of water from one day to the next and
    • any water collected is used promptly, or
    • the temperature of all water in the storage and distribution system is maintained at 63oC (145OF) or higher by automatic means, or
    • the water is treated with a suitable chemical to suppress bacterial propagation by means of an automatic metering device prior to the water entering the storage tank
  3. Clearly identify distribution lines and hose stations as “limited use reclaimed water
  4. Clearly describe and prominently display water handling practices and guidelines at appropriate locations within the establishment
  5. Ensure water lines are not permanently connected to product vessels, without a break to the atmosphere and sufficient automatic controls, to prevent the inadvertent addition of this water to product streams.

Category 3: Reclaimed water not meeting the above criteria may be used as feed water for boilers that is not used for generating culinary steam, or may be used in a thick, double walled, enclosed heat exchanger.

References