Chapter 19 Appendices
Appendix 12 Water reclaimed from the condensing of milk and milk products
- Appendix 12A Water Treatment Devices
- Appendix 12B Sterile Water for Rinsing of Aseptic Packages
- Appendix 12C Risk-Based Selection of Backflow Preventers for Dairy Establishments
Condensed water from milk evaporators and water reclaimed from milk and milk products may be re-used within the establishment. This water must be safe for its intended use and should not jeopardize the safety of the product through the introduction of chemical, microbiological or physical contaminants. Acceptable uses of this water falls into three categories:
- Reclaimed water which may be used for all potable water purposes including the production of culinary steam,
- Reclaimed water which may be used for limited purposes including the production of culinary steam, and
- Use of reclaimed water not meeting the requirements of this appendix.
Category 1 - Reclaimed water to be used for potable water purposes, including the production of culinary steam, shall meet the following requirements:
- Water must be monitored and controlled to ensure the water is safe and suitable for use:
- Water must be sampled daily for two weeks following initial approval of the installation and semi- annually thereafter.
- Water must be sampled daily for one week following any repairs or alterations to the system.
- Water must meet the following criteria, tested monthly, using acceptable test methodology:
- E. Coli (or thermotolerant coliforms) are absent in a 100 mL water sample. Depending on the jurisdiction, demonstration of the absence of total coliforms may be required in place of, or in addition to, the absence of E. Coli (or thermotolerant coliforms),
- Heterotrophic plate count (standard plate count) does not exceed 500 cfu/mL,
- The standard turbidity is less than 5 NTU (nephelometric turbidity units).
(Note: Health Canada guidelines say drinking water cannot exceed one NTU, unless it can be shown that the water is adequately disinfected, in which case it is drinkable up to five NTUs).
- The water must not impart any off-taste and off-odours. The water should not feel or appear slimy. The water must be assessed weekly for off-odours and appearance (clarity, colour).
- The usage of chemicals:
- Water treatment chemicals, where used, are listed in the "Reference Listing of Accepted Construction Materials, Packaging Materials and Non-Food Chemical Products" published by CFIA or the manufacturer has a "letter of no objection" from Health Canada.
- Where used, the addition of chemicals must be by an automatic metering device, prior to the water entering the storage tank, to assure satisfactory water quality in the storage tank at all times.
- Where used, a twice a day testing program for such added chemicals must be in effect
- Where used, chemicals do not pose a contamination risk to the water or the product.
- The operator must have procedures in place in the event that the water exceeds the requirements and poses a microbiological and chemical risk. For example the processor could install an automatic fail-safe monitoring device so that the water would be automatically diverted to the sewer if the water exceeded the standards.
- Design of the water storage system:
- Storage facilities are designed, constructed and maintained to prevent contamination, e.g. covered, properly constructed of material(s) that will not contaminate the water and should allow for periodic cleaning and sanitizing. For example, these could be approved materials from the CWWA (Canadian Water and Wastewater Association) or materials for such use as per manufacturer's guidelines. Without proper design, operation, and maintenance of these facilities, 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.
- The distribution system, within the establishment, must be a separate system with no cross-connections to a municipal or private water system.
Category 2 - Reclaimed water may be 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, items 2c) - 6 above must be satisfied and in addition:
- 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 approved chemical to suppress bacterial propagation by means of an automatic metering device prior to the water entering the storage tank; and that,
- Distribution lines and hose stations are clearly identified as "limited use reclaimed water"; and
- Water handling practices and guidelines are clearly described and prominently displayed at appropriate locations within the establishment; and
- These 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 requirements may be used as boiler feed water for boilers, not used for generating culinary steam, or a thick, double walled, enclosed heat exchanger.
References:
Grade A Pasteurized Milk Ordinance 1999 Revision
Guidelines for Canadian Drinking Water Quality Sixth Edition
Standard Methods for the Examination of Water and Wastewater, latest edition
Appendix 12A Water Treatment Devices
Depending on the source of the water, conditions of use, and magnitude and extent of microbiological contamination, disinfection may be needed occasionally over short periods of time or on a continuous basis.
Private wells can become contaminated if they are poorly constructed or improperly sifted or if they have been infiltrated by contaminated surface water. The aquifer (the water-bearing underground layer of porous rock or sand) itself can be a source of contamination. Surface waters and unprotected groundwater are susceptible to faecal contamination from humans, livestock, wild animals and house pets.
When water must be continuously disinfected because of the unacceptable quality of the supply, the possibility of sporadic contamination or the presence of cysts, a water treatment device incorporating filtration and disinfection should be used. There are several types of water treatment devices available for the disinfection of water. These can be divided into point-of-use devices which are portable and are used to treat the water at a single tap or multi-taps and point-of-entry devices which are installed on the main water supply and treat the water as it enters the facility. Since most disinfection systems require clear water to ensure maximum efficiency, it may be necessary to combine two specific devices, one to remove various organic or inorganic compounds or to reduce turbidity in the water and one to reduce microbiological contamination. It is recommended that the operator consult a water treatment specialist prior to installing a disinfection system to ensure the system will be effective and will be installed correctly.
The best approach to ensure complete disinfection of water intended for human use and consumption may be a multi-barrier one, consisting of collecting water from the cleanest source possible, followed by filtration and disinfection.
Some water treatment devices include:
- Chlorinators, iodinators and ultraviolet light (UV) are most practical to disinfect the water system.
Chlorine and iodine kill most disease-causing organisms and require short to moderate contact times, but do not provide protection against protozoa such as Giardia lamblia and Cryptosporidium parvum. It is recommended that if the presence of protozoa is probable, the water be filtered through a filter with a 1 micron or smaller pore size to remove these parasites and then treated with chlorine or iodine to kill bacteria and viruses. Iodine disinfection should not be used for long term continuous disinfection as ingestion in excessive amounts can be harmful.
UV devices are also effective against bacteria and viruses, produce no taste or odour and only require a few seconds exposure if the water is clear, but they do not ensure the safety of the water beyond point of application, so that flushing of the system is recommended after periods of non-use. In the case of UV devices a pre-filter should always be used to remove protozoan cysts and reduce turbidity, which will also improve the effectiveness of the UV light. If the water is above a certain level of turbidity post-filtration or if certain chemicals are present in the water, then UV disinfection will not be effective.
- Ceramic or glass fibre filters handle smaller amounts of water and are useful when water from just one tap is to be treated.
These filters can remove bacteria and protozoa from mildly contaminated water, but are not suitable for removing viruses or for treating highly contaminated water. When treating surface water, It is recommended that these filters be used in conjunction with disinfection.
- Distillers and ozonators are point-of-use devices running on electricity and require sufficient space to install.
Distillation is commonly used to reduce the levels of all chemicals in drinking water and are effective for the removal of inorganic chemicals including heavy metals and some organic chemicals, but are often combined with activated carbon for the removal of certain "volatile" chemicals. There are no known beneficial or harmful health effects associated with the ingestion of demineralized or distilled water.
Ozonators produce small quantities of ozone, a strong oxidizing agent that is effective in killing pathogens over a short period of time. It produces no taste or odour in the water. When using this method it is important to have good mixing of ozone with water. Unlike chlorine and iodine, ozone does not protect the water after application and is often combined with activated carbon filtration to achieve more complete water treatment.
Appendix 12B Sterile Water for Rinsing of Aseptic Packages
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Appendix 12C Risk-Based Selection of Backflow Preventers for Dairy Establishments
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