What is steam?
Steam is the gaseous state of water.
Saturated steam is steam mixed with liquid water in a stable state.
Culinary steam is saturated steam that is suitable for direct injection into food or direct contact with food or food contact surfaces.
Culinary steam is commonly used to prepare food. It can be a source of contamination when applied to a food (for example, in aseptic processing and packaging, or when cleaning or sterilizing food contact surfaces).
The boiler operation, water treatment management and steam distribution system can all influence the suitability of culinary steam for use. Culinary steam should be:
- free of boiler water treatment chemicals; and
- suitable for use.
The Canadian Food Inspection Agency (CFIA) created this document as a guideline to help food businesses comply with the Safe Food for Canadians Regulations.
You may use other guidance developed by provincial governments, industry associations, international partners or academic bodies as long as they can achieve the outcomes identified in the regulations. Always ensure that the guidance you choose is relevant for your particular business, product or products, and market requirements.
This document provides information on control measures to help prevent culinary steam from being a source of contamination to a food.
Refer to the Tell me more! section for additional sources of information that may help you ensure the culinary steam you use is suitable for use.
What's not included
While this document provides information on the safe use of culinary steam, it is not exhaustive – its suitability and the preventive control measures needed will depend on the size and complexity of the food business and be unique for each business.
This document does not address steam used on non-food contact surfaces or used to heat and establishment.
Roles and responsibilities
Food businesses are responsible for complying with the law. Compliance is demonstrated by ensuring that the commodities and processes for which they are responsible meet regulatory requirements. If a written preventive control plan (PCP) is required, the food business develops a PCP with supporting documents, monitors and maintains evidence of its implementation, and verifies that all control measures are effective.
The CFIA verifies the compliance of a food business by conducting activities that include inspection, and surveillance. When non-compliance is identified, the CFIA takes appropriate compliance and enforcement actions.
Boiler and feed water
Since culinary steam may come into direct contact with a food, it is important that the water used to manufacture the steam is sourced, treated and handled in a way to minimize contamination. This includes using:
- boiler feed water that is potable. For more information on treating source water, refer to the document Water for use in the preparation of food.
- qualified individuals for the design and operation of boiler feed water to prevent food contamination and maintain boiler operation
- volatile corrosion inhibitors (VCIs) and other chemicals to prevent corrosion and scale or to permit sludge removal from the boiler that are suitable for their intended use
- for the processing of milk and milk products, boiler water additives that do not contain the following chemicals:
- N,N-Bis (2-hydroxyethyl) Alkyl (C 12-C 18) amine derived from coconut oil
- Trisodium nitrilotriacetate
- tannins with caution, to remove sludge during boiler blow-down, because they can cause off odors
Boiler and steam generating equipment should be operated in a way that prevents foaming, priming, carryover and excessive incorporation of boiler water into the steam.
Carryover of boiler water additives into the steam could impart off-flavours to the food and contaminate the food or food contact surfaces with chemicals.
The continual evaporation of steam results in the concentration of dissolved impurities that can precipitate in the boiler and affect the production of steam. Carrying out a boiler blowdown, where a portion of the water is purged during operation, helps remove excess solids and prevents foaming and the carryover of impurities in the steam.
- You should follow the manufacturer's instructions on the recommended water level and the blow-down procedures
Steam supply and distribution system
The culinary steam supply and distribution system should be designed and operated to prevent contamination and allow for an adequate delivery of steam.
The suitability and safety of the boiler feed water for use to generate culinary steam should be monitored periodically. For example:
- Steam condensate samples should be taken from the line between the final steam-separating equipment and the point where steam is introduced into the food
- This sampling helps to identify any carryover of boiler water additives, causing off-flavours and chemical residues in the food
Tell me more! Further reading
The following references contain information that helps explain food safety controls, demonstrates how to develop them, and provides examples. The CFIA is not responsible for the content of documents that are created by other government agencies or international sources.
- Health Canada. Guidelines for Incidental Additive Submissions 2010
- Date modified: