Best Production Practices for Producing Safe, Quality Maple Syrup

About Lead Contamination

Exposure to lead is known to have adverse effects on human health, especially on the nervous system, and particularly in children. In recent years, efforts have been made to eliminate lead in food products, including maple syrup.

Lead contamination in maple syrup is largely associated with processing equipment (for example evaporators and buckets) that contain lead solder, but other sources are also possible. Maple sap and syrup can react with lead-containing surfaces, allowing lead to leach into them. Lead-bearing equipment includes, but is not restricted to:

  • soldering (e.g. soldered seams) on galvanized equipment manufactured before 1994;
  • soldering (e.g. soldered seams) on all other equipment manufactured before 1995, including stainless steel evaporators;
  • bronze and brass fittings; and
  • terneplate (a lead and tin alloy that was used in the past to coat iron and steel sheets; for example, old milk cans sometimes used for bulk storage of maple syrup are often constructed of terneplate material).

What you can do to avoid Lead Contamination

Protect your business and the maple industry's reputation by producing safe, high-quality maple syrup and by ensuring that your products do not become contaminated.

Keep in mind that all equipment and containers that come into contact with sap or syrup should be considered, including equipment and containers used in sap collection, syrup production/processing and storing syrup. Residency time can also be a factor in lead levels: the longer sap or syrup is in contact with lead surfaces, the greater the opportunity for lead to be absorbed into the syrup. All lead bearing equipment and containers should be replaced.

The following are practices that reduce the risk of lead contamination in sap and maple syrup:

Checking and Updating Your Equipment

  • new or used, equipment must be manufactured with food-grade materials, either stainless steel or food-grade plastic
  • make repairs using food-grade materials
  • use lead test kits to identify possible lead sources (purchase kits from equipment suppliers)

Sap Collection

  • use stainless steel or food-grade plastic spouts
  • use stainless steel, food-grade plastic or aluminum metal buckets or gathering equipment
  • gather sap from buckets daily
  • ensure pumps and vacuum systems are constructed of food grade materials
  • use food-grade polyethylene tubing with smooth interior surfaces
  • ensure fittings are food-grade plastic or stainless steel

Sap Storage

  • discard galvanized, corroded or damaged tanks
  • use only stainless steel, glass-lined, or food-grade plastic storage tanks

Boiling Sap

  • use lead-free pre-heaters
  • use modern TIG welded stainless steel evaporator pans or pans assembled using lead-free solder
  • do not use pans having lead soldered joints or lead soldered repairs
  • replace brass or bronze fittings with food-grade plastic or stainless steel
  • flush pans with water to ensure removal of cleaning residues, dirt, and sugar sand (niter)
  • ensure repairs are completed using lead-free solder, tungsten inert gas (TIG) or metal inert gas (MIG) welding

Filtering Syrup

Proper syrup filtering is critical.

  • filter syrup into food-grade containers
  • never filter syrup into old milk cans
  • use Orlon® felt filters and/or a filter press
  • use filters in good condition
  • discard worn or damaged filters
  • use clean, unscented filters
  • use filters with a small micron size (e.g. 5 micron)
  • wash filters using only warm water without soaps or detergents

Bulk Syrup Storage

At this production stage:

  • ensure that each day's syrup production is batch-coded
  • use stainless steel, glass-lined, or food-grade plastic storage containers
  • ensure that containers and drums are clean, sanitized and free of odours
  • never store syrup in containers such as old milk cans
  • never store syrup in corroded containers or drums
  • never use containers or drums that have been repaired or painted with unknown or potentially hazardous substances or that have been used to store materials other than food

Test Your Syrup

With each coded batch:

  • if you are uncertain about the presence of lead-bearing equipment, test each batch prior to packing and selling to ensure it is not contaminated with lead
  • test every incoming lot if you buy bulk syrup
  • syrup testing should be done by a recognized accredited laboratory

For the location of an accredited laboratory near you, please contact us.

For Quality and Food Safety ...

Paul Bailey

Risk Identification and Management Coordinator
Foods of Plant Origin
(519) 826-4380

For Prodution and Forestry ...

Todd Leuty
Agroforestry Specialist
Agriculture Development Branch
(519) 826-3215


For more information:
Toll Free: 1-877-424-1300
Author: OMAFRA Staff)
Creation Date: 27 March 2012
Last Reviewed: 30 April 2012