A Guide to Making Your Own Tasty Natural Nutritious Maple Syrup

It is the end of Winter which means a new season of sapping and sugaring! Making your own maple syrup is a joyful activity in nature that will reward you with an out-of-this-world maple syrup, amazingly tasty and nutritious. But like all other good things in life, it needs more skills, time and patience than money. I explain all the steps in this article which shares most of last year’s article plus new videos from this year.

If you find a healthy maple tree (not too young, or too dried up, and preferably in an old growth forest), it can share with you 0.5-1 gallon of sap a day (containing 1-2% sugar and a lot of minerals), which can be boiled down to maple syrup (60%+ sugar content. Once you make and taste your own maple syrup, you would not want to buy the store brands anymore (even the pure maple syrup, let alone the high fructose types mislabeled as maple syrup). The following article explains some little-known tricks to make your own maple syrup. Like everything else good in life and nature, you need patience and time (taken away from money making!) and patience, for which you will be rewarded with joy, wisdom, health, peace and contentment.

The Sap

Maple syrup is created by a lengthy process that concentrates the natural sugars in maple sap. Trees use sap, like humans use blood, to feed their branches, leaves and roots with natural simple sugars and minerals. The maple tree most commonly tapped in syrup production, the sugar maple, Acer Saccharum, is a tree native to the eastern half of North America, growing as a large and stately tree in woods and open meadows, having gray bark and 5-lobed leaves. In states such as Vermont and New Hampshire, the sugar maple is sometimes the only tree found in some forests, forming dense groves of large trees. It provides a beautiful and colorful display of gold, red, and orange colors in autumn. The sugar maple grows very well in cold, rocky, and steep areas, so it is a common sight in most regions of the Appalachian mountain range. Its presence is much more common in the higher and colder regions of eastern North America than in the warmer lowlands by the ocean. Sugar maples are hardy and versatile. They can be found growing in dark forest canopies as understory trees as well as in open sunny meadows. Large-scale commercial syrup producers mainly base their operations in the New England states and in Canada, where healthy maple groves are common and close in proximity. Proper access to the location of the maple grove is also essential, as difficult locations can hinder worker access to maples, such as in very steep and rocky areas.

In warmer seasons, a large sugar maple tree with its crown at the top of the forest canopy might move (due to photosynthetic-induced transpiration and diffusive root pressures) around 200 liters of water from the roots to the evaporating surfaces of leaves, 30 meters above the forest floor. Mineral nutrients from the soil, along with sugar and hormones and other physiological constituents manufactured or stored in the roots or stems sometimes also rise dissolved in the water and collectively form the sap. The sap ascends from root to leaf in the xylem made of vascular tracheary elements (shown in the picture).

Maple sap flow during the leafless season is physiologically unique in that it is largely independent of root pressure and only occurs on occasions between October and April when warm days follow freezing nights. Maple winter sap flow is caused by pressure in the stem generated by alternating daily cycles of night freezes and warm days. Cool evening temperatures generate negative pressure from the dissolution of gases in the xylem, which were seeded in from adjacent parenchyma and intercellular spaces. The negative pressure replicates the effect of transpiration, which draws still-liquid water from the soil into the roots. As the night freeze deepens, water freezes along the inner walls of the hollow fiber cells adjacent to the xylem and in intercellular spaces. Eventually vaporized water on the surfaces of all cells freezes.

The ice formation compresses and traps gases in the stem. The heat of the day melts the ice and causes expansion of the compressed gases, which generates positive pressure in the stem that pushes the sap up the stem and out the nearest exit, if one exists, such as a maple producer’s spile. Applying vacuum pressure to the tap allows a maple producer to collect up to three times the normal amount of sap, and doing so has been the industry standard since the late sixties although for our own home use, we don’t like to apply vacuum or insert multiple tapping points on our trees. Our small tapping points are no different than a bird poking a small hole on the tree trunk and will heal in about 6 weeks. We don’t use synthetic chemicals to seal the tapping holes. We also don’t tap thin young small trees (less than 12” in diameter) or older trees that seem unhealthy.

The sugar in the sap stream is mobilized in late winter and exuded into the xylem sapstream to fuel flowering and leaf expansion (maples flower before they leaf out). Most of the carbohydrates in the rays are actually stored as starch grains, and an enzyme released into the xylem throughout late winter converts the starch to sucrose and mobilizes it in the xylem. Sap sugar content also varies within a sap flow season, peaking in the middle. Therefore, there is quite an art to the timing of the tree tap. Producers should tap right before the peak sugar content sap flows. If they tap too early, the tap site might dry out, and they will collect mostly lower sugar content sap. We wait until daily freeze-thaw temperature cycles fluctuate +/- 10 to 15 degree Fahrenheit above and below the freezing point (of 32 degrees), that create enough pressure and flow in the sap channels. In our area in Pennsylvania, this usually happens in early February, which signal the beginning of tapping season. The larger the temperature difference between the night freeze and the daily thaw and greater the number of days in a season with big freeze-thaw cycles, the greater will be the volume of sap collected.

Maple syrup is mostly sucrose, but the maple xylem sap stream also contains glucose, inorganic salts (a lot of manganese and zinc and some magnesium, calcium, potassium), protein precursors (peptides and amino acids), riboflavin (Vitamin B2), some enzymes, minerals and a few mystery organic compounds. The sugar content question is economically critical. If a sugar maple canopy sees enough sun and has enough water and nutrients in a summer to photosynthesize more sugar than it needs, it would store it for higher sugar-content sap in the Winter. Generally speaking, shade-tolerant trees seem to always expect to have all or part of their future canopy shaded, so they save sugar to survive the lean times.

To make syrup, sap is boiled down until it is about 67% sugar. This means that if the sap has 2% sugar, as is typical for sugar maples, it takes 44 gallons of sap to make one gallon of syrup (the formula is 88.2 divided by initial sap sugar content, in percent). The darker color and more robust flavor of Grade B maple syrups indicate lower sugar content (say 1%) in the sap. More boiling means more heat and darker color. Fermentation happens in syrups with less than 50% sugar content. We sometimes stop our boiling (see below) at 50% sugar content and refrigerate the thin syrup for use within a few weeks (before extensive fermentation occurs). I also sometimes hot-can and then refrigerate some partly boiled/concentrated sap (about 5% sugar) as my morning natural mineral/vitamin boost drink. It’s superbly refreshing with a hint of maple flavor.

Unlike our home-made syrup (for our own use), many large-scale commercial syrup producers run their sap through a reverse osmosis machine to remove some of the water from the sap to concentrate the solution before the boiling begins, so that less time and fuel will be necessary to reach the syrup stage. Our home-mase syrup has some gritty sugar-sand with it, which we believe preserves the syrup and is a source of its minerals and polyphenols.

Tapping and Collecting Sap

Now we share the process we use to collect and boil our sap. We use a cordless drill and a 5/16” drill bit to make a horizontal hole into the tree about 2 inches deep, and remove the wood pulp generated to leave a clean hole. If you have picked the right tree and season, almost immediately, sap from the tree with the consistency of water flows out from the hole (see the video in the opening section). We then insert 5/16” sterilized stainless steel taps (called spiles) into the hole. Spiles are shaped like small hollow tubes that act like a channel and conduit for the sap to flow from inside the tree into collection tubes. After the spiles are gently hammered into the drilled hole (we use a clean towel over the end of the spile before gently hammering it in), We attach a small vinyl tube (5/16” inner diameter) from the spile into a collection container, such as a 1 or 5 gallon clean food grade bucket or container. This picture shows several sugar maple trees being tapped, with vinyl tubing running from trees to 5 gallon collection buckets.

Over the course of several days, the buckets begin to fill up with sap. With freeze-thaw cycles in between 50 degrees Fahrenheit (daytime) and 20 degrees Fahrenheit (night time), the flow of the sap may exceed one gallon per day for each healthy tree. However, most trees normally produce only half of this amount throughout the tapping season. We collect the sap from the buckets (into empty clean food grade buckets to carry back to the boiling pan) once they are nearly filled to avoid fermentation of the sugary sap during warmer days. Fermented sap has to be thrown away and cannot be used for maple syrup production. Also, we remove the frozen water (ice) from the top and only collect the unfrozen sap (with sugar).

Boiling Sap and Bottling Syrup

With buckets and sap collected, the worker brings them to his boiling area. The boiling area consists of an evaporator (boiling pan/pot), evaporator support (cement, brick, or metal), and firebox (where the fire can be built; normally under the evaporator) with a small chimney to carry off smoke. The evaporator is made of food-grade steel, and sometimes built sitting inside the firebox for maximum surface area of the pan exposed to fire, speeding up evaporation. The boiling area can be either indoors or outdoors, depending on the size and scale of the boiling operation. Small syrup producers boil syrup outdoors, while large operations have an indoor fire-proof area to protect workers from wind, cold, and excessive steam/smoke from the boiling.

With sap collected in quantities of 30 gallons or more (for small producers), we fill the evaporator pan with sap. We use a cheese cloth and stainless steel strainer to filter any ants, bugs, dust and wood particles. Then, we build a wood fire underneath the pan until a rolling boil of sap is achieved, causing rapid evaporation of water. The sap is kept at a constant boil, and the fire is monitored closely. The picture shows a small-scale boiling area using a 40-gallon evaporator with cinderblock walls supporting the evaporator and containing the firebox.

We continue boiling until the sap reaches a sugar content of 50-67% (see my notes above about the 50% syrup limitations). To reach this sugar content, we usually boil off about 40 gallons of sap to make 0.5-1 gallon of syrup. One useful tool to measure the concentration of sugar in the syrup or sap is a Brix refractometer.

At 66% sugar, the sap can be called syrup with a thick consistency and sweet taste. Boiling time ranges from about 1-2 hours for every 10 gallons of sap. Sometimes we transfer the syrup at around 30% sugar content and finish the process in a pot on a stove. We drains the evaporator or pot of syrup using either a spigot or by tipping them. The syrup is poured into smaller metal containers after passing through stainless steel strainers with filters (like cotton cheese cloth) to remove any impurities. Once the syrup is filtered, we bottle it into glass jars. Due to its high sugar content (if above 60% or so), the syrup would resist spoilage or fermentation.

Large scale commercial outfits in States like Vermont use complex sugaring processes which are described in other documents.

Riboflavin is essential in the formation of coenzymes involved in energy metabolism, cellular respiration, and antibody production, as well as normal growth and development. Prescribed to treat corneal thinning, and taken orally, Riboflavin may reduce the incidence of headaches in adults.