Current situation

Many maple producers began tapping maple trees late last week and during the weekend.  Other maple producers may still be waiting a few more days before tapping trees.   A few early sap flows were reported late last week in southwestern Ontario and along the north shore of Lake Ontario to Prince Edward County.   Taps on average can flow for up to 5 or 6 weeks before sap flow begins to dry up.  It is difficult to generalize predictions for each sap flow event across the entire province, from east to west and north to south.  It is better for each maple producer to pay close attention to weather forecasts in their area to predict upcoming sap runs.  New maple producers can contact other local experienced producers to learn prediction methods.  Watch for consecutive weather conditions of - 5 ºC night followed by + 5 ºC during days, which will encourage sap to flow.

Be careful not to sell yourself short on pricing your pure maple products.   Under-pricing of maple syrup remains an issue in some central regions of the province, which can hurt other producers.  Continue to encourage all maple producers in the province to cooperatively set reasonable prices for syrup, at levels that enable healthy profitability for a sustainable maple industry.

Filtering sap and syrup

New and traditional methods and equipment for filtering both sap and finished syrup are available from equipment dealers.  Proper filtration techniques to produce clear quality syrup can sometimes be a challenge, especially for new maple syrup producers.   Where filter bags or flat cloth filters are used, be sure they are as clean as possible before filtering begins.  Old stained or damaged filters should be replaced with new filters.  Wash and clean cloth filters in hot water between each use and let them air dry in a breezy area out of direct sunlight.  Soaps, detergents and bleach treatments on filters are not advised and can leave residual odours which can impart off-flavour in syrup.  Frequent washing of cloth filters in hot water is ideal.

For cylindrical cartridge filters or pressured press filters, make sure these are in good working order with the first syrup run.  Replace or clean filter cartridges as necessary to ensure the finished syrup is running clear and not cloudy.   Where filtration problems are encountered, maple producers can often find good problem-solving advice from experienced maple producers or from maple equipment dealers.  New stainless steel filtration technology is being tested by some maple producers this year and may provide improvements over other filter equipment.

Storing raw sap

Early in the sap run season, raw sap can be stored in tanks for longer periods while storage tanks remain cold.   Sap that is held at temperatures between 0 ºC and 3 ºC can be collected and held for 2 or 3 days until a full batch is ready to process into syrup.  Sap storage temperatures between 0 ºC and 3 ºC will prevent new microbial growth.   As the season progresses however, and sap storage tank temperatures warm up, such as 10 ºC or higher, maple producers should try to process all raw sap as quickly as possible to minimize sap storage time.  

Microbial growth can occur very quickly in warmer raw sap during storage, which can lead to degraded quality and off-flavours in finished syrup.  High microbial activity in sap can convert too much sucrose to invert sugars, glucose and fructose.  Invert sugars react to the heat of cooking differently than sucrose sugars and, if excessive, can lead to formation of unpleasant or burnt flavours.   Microbial activity in raw sap can also change the chemistry of sap as enzymes break down proteins and other sap constituents.  

Therefore as weather conditions warm, plan to process raw sap sooner than later.  Minimize sap storage time to prevent microbial breakdown and to provide better quality maple syrup and improved value-added maple products.  

Tree health observations

Many maple producers in the province will have taps installed by now or are in the process of drilling tap holes and setting spouts.   The process of drilling tap holes is a good time to assess how healthy the sugar maple trees are.   Many maple producers hire workers to help drill taps and it is useful to teach workers to spot problems in trees while drilling.  Make note of how much healthy wood is observed and how much unhealthy stained wood, or punky rotted wood is encountered while drilling the tap holes.  Healthy drill shavings should be creamy white in colour with a hard solid feel during drilling.  Unhealthy wood will be brown to dark brown in colour or punky and the drill may pass too easily into softened wood.   Excessive encounters with stained or rotted wood in the maple trees may be an indication that the sugar bush is not in good health.

Poor sugar bush health may be due to over-tapping during previous seasons.  Observe previous tap holes.  Are they showing signs of healing and closure with new wood?  Various environmental stresses can cause sugar bush decline.  Stress such as summer and fall drought, excessive flooding during previous growing seasons, excessive insect pest defoliation or disease can cause stress to trees.  Recent poor logging practices can cause soil compaction and root or trunk damage to remaining trees.   Where too much unhealthy wood is encountered while tapping, some guidance from a forest consultant may be useful to help ensure the health of the sugar bush is given top priority.  Over time, and with careful management planning, many unhealthy sugar bushes can be brought back to a better condition and will usually lead to improved maple syrup production for the future.

Measurement equipment

Calibrating thermometers and refractometers prior to every batch of syrup processed is important to ensure that the final minimum sugar concentration or ºBrix reading in finished syrup is achieved.  The minimum sugar concentration in finished syrup is º66 Brix.   A Brix level between 66.5º to 67.5º provides a more pronounced maple flavour and better mouth-feel viscosity in finished syrup.  Calibrating measurement equipment even one or two degrees lower than accurate will result in finished syrup that has too high a Brix level.  Brix levels of 68º or higher can lead to filtration problems and crystallization of sugar after bottling.  Sugar concentrations that are higher than acceptable levels also cost the producer unnecessarily more dollars in fuel expenses and labour.  Inaccurate calibration may have lead to excessively high sugar levels last year in many finished maple syrup samples that were tested (note: off-density correction from previous agriphone reports).

Record Keeping

It is important to keep records during each syrup run to help you with management decisions.  Things to record each run may include: temperature and weather conditions, barometric pressure, sap flow volume and duration, sap sugar concentration, sap storage time, filtration problems and remedies, nitre produced and fuel consumed.  Record each batch of syrup and label all containers with a batch coding system that is easy for you to organize.  Batch coding is very important in the event that a recall must be carried out after sale.  Also, record the amount of time that you and all workers have spent on every job, including marketing product, in order to determine the true labour costs involved in your maple business.   The more detailed the records you keep the better.   

This report has been prepared by Todd Leuty, Agroforestry Specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs.