Contents
What is maple syrup ?
No one really knows who first discovered how to make syrup and sugar from the sap of a maple tree.
The yield of sap varies greatly with the method of tapping, the size of the tree, and seasonal differences. Sap yield is usually expressed in terms of the number of tapholes, rather than the number of trees. The average yield for a taphole is from five to 15 gallons. However, under favorable conditions, a single taphole can produce as much as 40 to 80 gallons of sap in a single year. It takes about 10 gallons (37.85 liters) of sap to produce one quart (946 ml) of maple syrup 1.
What kind of trees are used to make maple syrup ?
Sugar maple and black maple are the two species of trees most used in making maple syrup. Both are long-lived hardwood species common in deciduous forests in the northeast. Red maple is another species that is frequently tapped for maple syrup production. Several other species in the maple family also produce a sugary sap, but are less frequently used due to undesirable sap characteristics. These species include silver maple, Norway maple and box elder. Birch and black walnut trees can also be tapped and each produce their own distinctive syrup.
How the maple tree form the sap
Understanding how maple sap is formed requires some knowledge about tree physiology. In the later summer and fall, maple trees virtually stop growing and begin storing excess starches throughout the sapwood, especially in cells called ray cells. This excess starch remains in storage as long as the wood remains colder than about 40 degrees F. Whenever wood temperatures reach around 40 degrees F, enzymes in the ray cells change the starches to sugars, largely sucrose. This sugar then passes into the tree sap.
As the temperature increases to about 45 degrees F, the enzymes stop functioning and sugar is no longer produced. In March and April, the sugar changes back to starch—except during periods of flow.
Rising temperature creates pressure inside trees, causing sap to flow. When a hole is bored into a tree, wood fibers that are water- (sap-) carrying vessels are severed, so sap drips out of the tree.
A tree should be at least 10 inches in diameter, measured at 4 1/2 feet above the ground, before tapping 1. Trees between 10 and 20 inches in diameter should have no more than one tap per tree. A second tap may be added to trees between 20 and 25 inches in diameter. Trees over 25 inches in diameter can sustain three taps. No tree should ever have more than three taps. The shape and size of the crown are also important. Trees with large crowns extending down towards the ground are usually the best sap producers.
How the maple sap is collected
Typically, this raw sap has a sugar content of about 2%. The sap can be collected in many different ways. The traditional method, still used by many small producers, is driving a small spout into the tap hole and hanging a bucket or bag from the tree. The sap is then collected periodically from these small containers and placed in a storage tank. More commonly, sap is collected in plastic tubing systems that direct the flow of sap to a central storage area. These systems usually consist of smaller, flexible lines called lateral lines that attach to plastic spouts that are driven into the tap hole. These lateral lines flow into larger diameter lines, called main lines, that flow into storage tanks. Most larger maple producers use vacuum pumps to create negative pressure in their collection systems. Using vacuum dramatically increases the amount of sap production.
How maple tree sap turned into maple syrup
In order to turn maple sap into syrup, it needs to be concentrated and cooked at high temperatures. Sap can be concentrated in two ways.
- The traditional method is boiling the sap in a specialized pan called an evaporator 2. As the sap is heated, water evaporates, leaving behind concentrated sugars and other compounds that give maple syrup its distinctive taste. Sap is boiled in this fashion until it reaches a sugar concentration of about 66-67%. This occurs at a temperature of around 219 degrees Fahrenheit. The heat also caramelizes a small amount of the sugar, resulting in its characteristic color and maple flavor.
- Another way to concentrate maple tree sap is reverse osmosis 2. In this process, sap is pushed at high pressure through special filters, called membranes, that remove purified water from the sap. Most commercial producers use reverse osmosis to concentrate sap before cooking it into finished syrup in an evaporator. Using reverse osmosis reduces processing time and energy requirements by 75% or more.
How to store maple syrup
Store your maple syrup in a cool, dry place. After a container has been opened for use, it must be refrigerated. Should mold form on maple syrup that has been stored for several months, discard the syrup: there is the potential for contamination by a micro-organism that can cause food-borne illness 1.
Maple Syrup Grades
Maple syrup, which may also be spelled “maple sirop” or “maple sirup,” means the liquid derived by concentration and heat treatment of the sap of maple (Acer species) trees, or by the solution in water of maple sugar or maple concentrate made from such sap. The solids content of maple syrup may not be less than 66% by weight or more than 68.9% by weight, as measured in Brix units at a temperature of 68°F. Brix (symbol °Bx) is the sugar content of an aqueous solution. One degree Brix is 1 gram of sucrose in 100 grams of solution and represents the strength of the solution as percentage by mass.
Under the older maple syrup grading system, darker maple syrups with rich bold flavor were labeled as Grade B for Reprocessing and are not intended for retail sale. However, consumers are increasingly seeking the darkest color class of maple syrup for cooking and table use.
- Grade A Is Not Better Than Grade B
Grade B syrup (Processing Grade) has a darker color and deeper flavor than grade A, but that doesn’t make it inferior. Many people prefer the more intense flavor of grade B.
However in March 2015, the International Maple Syrup Institute represents maple syrup producers, state governments and associations, vendors, maple equipment manufacturers, organizations, and others in Canada and the United States – petitioned the Agricultural Marketing Service of the U.S. Department of Agriculture (USDA) to develop a new harmonized standard and grades for maple syrups replacing USDA existing maple syrup grade statement and color descriptor standards 3.
Due to that new grading standards, now ALL maple syrup is grade A, followed by a color/flavor description:
- Grade A Light Amber is now Grade A Golden Color/Delicate Taste
- Grade A Medium Amber is now Grade A Amber Color/Rich Taste
- Grade A Dark Amber is now Grade A Dark Color/Robust Taste
- Grade B is now Grade A Very Dark Color/Strong Taste
The new revision of the U.S. standards will categorize Grade B syrup that contains no damage or off flavors/odors as Grade A to allow the darker syrup to be packaged in retail size containers (less than 5 gallons). Specifically, the Grade A classification is revised to include four new color and flavor classes of maple syrup:
- U.S. Grade A Golden (delicate taste, ≥ 75.0 percent light transmittance (%Tc))
- U.S. Grade A Amber (rich taste, 50.0-74.9%Tc)
- U.S. Grade A Dark (robust taste, 25.0-49.9%Tc)
- U.S. Grade A Very Dark (strong taste, < 25.0%Tc)
Here is the new Official Standards for Maple Syrup Grades obtained from The International Maple Syrup Institute 3, 4.
- “Grade A Golden Color Delicate Taste” means pure maple syrup that is free of any material other than pure, clear liquid maple syrup in sanitary condition; has a color for light transmittance of not less than 75%Tc; has a delicate taste; and has a light to more pronounced golden color. Grade A Golden Color Delicate Taste maple syrup must be free of sugar crystals and may not be damaged in any way.
- “Grade A Amber Color Rich Taste” means pure maple syrup that is free of any material other than pure, clear liquid maple syrup in sanitary condition; has a color for light transmittance of less than 75%Tc but not less than 50%Tc; has a rich or full-bodied taste; and has a light amber color. Grade A Amber Color Rich Taste maple syrup must be free of sugar crystals and may not be damaged in any way.
- “Grade A Dark Color Robust Taste” means pure maple syrup that is free of any material other than pure, clear liquid maple syrup in sanitary condition; has a color for light transmittance of less than 50%Tc but not less than 25%Tc; has a more robust or stronger taste than maple syrup in lighter color classes; and has a dark color. Grade A Dark Color Rich Taste maple syrup must be free of sugar crystals and may not be damaged in any way.
- “Grade A Very Dark Color Strong Taste” means pure maple syrup that is free of any material other than pure, clear liquid maple syrup in sanitary condition; has a color for light transmittance of less than 25%Tc; has a very strong taste; and has a very dark color. Grade A Very Dark Color Rich Taste maple syrup must be free of sugar crystals and may not be damaged in any way.
- “Processing Grade” means any maple syrup that does not qualify for Grade A labeling, including off-flavored maple syrup and syrup with objectionable odors, turbidity, or sediment. Processing Grade maple syrup may not be sold in retail markets and must be packed in 5-gallon or larger containers.
Although this change went into effect in March 2015, not all maple syrup producers have switched over, so you may still see the old grades on labels.
Recently an expert panel of tasters evaluated 14 maple syrups—eight dark, five amber, and one golden—both brand names and private label. For the test, the syrups were served in dark red cups so the color differences wouldn’t influence the experts’ evaluations.
What’s the best type to serve at breakfast or brunch ? It depends on your taste. The panel found the dark syrups to be more intense and complex than the amber syrups, but both types had clean maple flavors. The differences between the colors were quite noticeable when they tasted the golden, amber, and dark color offerings from one brand, side by side. The golden syrup was the most sweet with the mildest flavor. The amber syrup had more maple flavor and the dark syrup was complex with big molasses and intense maple flavors.
Maple Syrup Nutrition and Calories Content
There are variations in concentrations of sugar, nitrogen, phosphorus, potassium, calcium, and magnesium of sap from sugar maple (Acer saccharum, Marsh.) trees. These maple syrup nutritional and calories contents differences are related to the time of sap collection and result in variation of the same components in pure maple syrup. Thirty milliliters (2 tablespoons) of pure maple syrup may contain 3 to 6 mg of phosphorus, 10 to 30 mg of potassium, 40 to 80 mg of calcium, and 4 to 25 mg of magnesium 5.
Table 1. Maple Syrup Nutrition Content
Nutrient | Unit | Value per 100 g | tbsp 20 g | serving 1/4 cup 83 g | cup 315 g | ||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Approximates | |||||||||||||||||||
Water | g | 32.39 | 6.48 | 26.88 | 102.03 | ||||||||||||||
Energy | kcal | 260 | 52 | 216 | 819 | ||||||||||||||
Protein | g | 0.04 | 0.01 | 0.03 | 0.13 | ||||||||||||||
Total lipid (fat) | g | 0.06 | 0.01 | 0.05 | 0.19 | ||||||||||||||
Carbohydrate, by difference | g | 67.04 | 13.41 | 55.64 | 211.18 | ||||||||||||||
Fiber, total dietary | g | 0.0 | 0.0 | 0.0 | 0.0 | ||||||||||||||
Sugars, total | g | 60.46 | 12.09 | 50.18 | 190.45 | ||||||||||||||
Minerals | |||||||||||||||||||
Calcium, Ca | mg | 102 | 20 | 85 | 321 | ||||||||||||||
Iron, Fe | mg | 0.11 | 0.02 | 0.09 | 0.35 | ||||||||||||||
Magnesium, Mg | mg | 21 | 4 | 17 | 66 | ||||||||||||||
Phosphorus, P | mg | 2 | 0 | 2 | 6 | ||||||||||||||
Potassium, K | mg | 212 | 42 | 176 | 668 | ||||||||||||||
Sodium, Na | mg | 12 | 2 | 10 | 38 | ||||||||||||||
Zinc, Zn | mg | 1.47 | 0.29 | 1.22 | 4.63 | ||||||||||||||
Vitamins | |||||||||||||||||||
Vitamin C, total ascorbic acid | mg | 0.0 | 0.0 | 0.0 | 0.0 | ||||||||||||||
Thiamin | mg | 0.066 | 0.013 | 0.055 | 0.208 | ||||||||||||||
Riboflavin | mg | 1.270 | 0.254 | 1.054 | 4.000 | ||||||||||||||
Niacin | mg | 0.081 | 0.016 | 0.067 | 0.255 | ||||||||||||||
Vitamin B-6 | mg | 0.002 | 0.000 | 0.002 | 0.006 | ||||||||||||||
Folate, DFE | µg | 0 | 0 | 0 | 0 | ||||||||||||||
Vitamin B-12 | µg | 0.00 | 0.00 | 0.00 | 0.00 | ||||||||||||||
Vitamin A, RAE | µg | 0 | 0 | 0 | 0 | ||||||||||||||
Vitamin A, IU | IU | 0 | 0 | 0 | 0 | ||||||||||||||
Vitamin E (alpha-tocopherol) | mg | 0.00 | 0.00 | 0.00 | 0.00 | ||||||||||||||
Vitamin D (D2 + D3) | µg | 0.0 | 0.0 | 0.0 | 0.0 | ||||||||||||||
Vitamin D | IU | 0 | 0 | 0 | 0 | ||||||||||||||
Vitamin K (phylloquinone) | µg | 0.0 | 0.0 | 0.0 | 0.0 | ||||||||||||||
Lipids | |||||||||||||||||||
Fatty acids, total saturated | g | 0.007 | 0.001 | 0.006 | 0.022 | ||||||||||||||
Fatty acids, total monounsaturated | g | 0.011 | 0.002 | 0.009 | 0.035 | ||||||||||||||
Fatty acids, total polyunsaturated | g | 0.017 | 0.003 | 0.014 | 0.054 | ||||||||||||||
Cholesterol | mg | 0 | 0 | 0 | 0 | ||||||||||||||
Other | |||||||||||||||||||
Caffeine | mg | 0 | 0 | 0 | 0 |
Table 2. 100% Pure Maple Syrup (Certified Organic) Nutrition Content
Nutrient | Unit | 60 ml | Value per 100 ml | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Approximates | |||||||||||||||||||
Energy | kcal | 210 | 350 | ||||||||||||||||
Protein | g | 0.00 | 0.00 | ||||||||||||||||
Total lipid (fat) | g | 0.00 | 0.00 | ||||||||||||||||
Carbohydrate, by difference | g | 53.00 | 88.33 | ||||||||||||||||
Minerals | |||||||||||||||||||
Calcium, Ca | mg | 60 | 100 | ||||||||||||||||
Sodium, Na | mg | 7 | 12 | ||||||||||||||||
Lipids | |||||||||||||||||||
Cholesterol | mg | 0 | 0 |
Table 3. Grade A 100% Pure Maple Syrup (from the sap of maple trees) Nutrition Content
Nutrient | Unit | 60 ml | Value per 100 ml | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Approximates | |||||||||||||||||||
Energy | kcal | 200 | 333 | ||||||||||||||||
Protein | g | 0.00 | 0.00 | ||||||||||||||||
Total lipid (fat) | g | 0.00 | 0.00 | ||||||||||||||||
Carbohydrate, by difference | g | 53.00 | 88.33 | ||||||||||||||||
Fiber, total dietary | g | 0.0 | 0.0 | ||||||||||||||||
Sugars, total | g | 53.00 | 88.33 | ||||||||||||||||
Minerals | |||||||||||||||||||
Calcium, Ca | mg | 60 | 100 | ||||||||||||||||
Iron, Fe | mg | 0.72 | 1.20 | ||||||||||||||||
Sodium, Na | mg | 5 | 8 | ||||||||||||||||
Vitamins | |||||||||||||||||||
Vitamin C, total ascorbic acid | mg | 0.0 | 0.0 | ||||||||||||||||
Vitamin A, IU | IU | 0 | 0 | ||||||||||||||||
Lipids | |||||||||||||||||||
Fatty acids, total saturated | g | 0.000 | 0.000 | ||||||||||||||||
Fatty acids, total trans | g | 0.000 | 0.000 | ||||||||||||||||
Cholesterol | mg | 0 | 0 |
Table 4. Grade B Maple Syrup (Organic) Nutrition Content
Nutrient | Unit | 60 ml | Value per 100 ml | ||||||||||||||||
---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
Approximates | |||||||||||||||||||
Energy | kcal | 200 | 333 | ||||||||||||||||
Protein | g | 0.00 | 0.00 | ||||||||||||||||
Total lipid (fat) | g | 0.00 | 0.00 | ||||||||||||||||
Carbohydrate, by difference | g | 53.00 | 88.33 | ||||||||||||||||
Fiber, total dietary | g | 0.0 | 0.0 | ||||||||||||||||
Sugars, total | g | 53.00 | 88.33 | ||||||||||||||||
Minerals | |||||||||||||||||||
Calcium, Ca | mg | 80 | 133 | ||||||||||||||||
Iron, Fe | mg | 1.44 | 2.40 | ||||||||||||||||
Sodium, Na | mg | 5 | 8 | ||||||||||||||||
Vitamins | |||||||||||||||||||
Vitamin C, total ascorbic acid | mg | 0.0 | 0.0 | ||||||||||||||||
Vitamin A, IU | IU | 0 | 0 | ||||||||||||||||
Lipids | |||||||||||||||||||
Fatty acids, total saturated | g | 0.000 | 0.000 | ||||||||||||||||
Fatty acids, total trans | g | 0.000 | 0.000 | ||||||||||||||||
Cholesterol | mg | 0 | 0 |
Are there any health benefits to maple syrup ?
There is little or no health benefits to maple syrup. Maple syrup just add sweetness and flavors to your foods.
Is maple syrup better for you than sugar ?
Sugars are a ubiquitous component of our food supply. Over the years, however, sugar intake has been claimed to be associated with several diet-related chronic diseases: type 2 diabetes, cardiovascular disease, obesity, dental caries, metabolic syndrome and hyperactivity in adults and children 7, 8. Currently in the U.S., added sugars account on average for almost 270 calories, or more than 13 percent of calories per day in the U.S. population 9. One of overwhelming concerns regarding sugars is the potential for excess energy intake from sugars resulting in weight gain and displacement of more nutrient-dense foods 7.
If you consume ¼-cup (60 ml) of maple syrup—the amount listed as a serving on the nutrition facts label—you’d get about 200 calories and 53 grams of sugars—more than in a 355 ml can of cola that has about 39 grams of sugar and about 151 calories, so go easy on the maple syrup.
Maple Syrup Is Not Healthier Than Sugar
Maple syrup does contain more of some nutrients (e.g. calcium) than table sugar —but it certainly isn’t a health food. Whether it’s an ingredient in a packaged food or poured on pancakes or oatmeal, maple syrup counts toward your daily added sugars intake. Added sugars are the sugars that are added to food in processing or cooking, not the sugars that are an intrinsic part of fruit or dairy. The latest U.S. Dietary Guidelines put a spotlight on added sugars and for the first time there is a recommended limit: no more than 10 percent of your daily calories 9.
- The University of Maine. How to Tap Maple Trees and Make Maple Syrup. https://extension.umaine.edu/publications/7036e/[↩][↩][↩]
- Cornell University. About Maple Syrup. http://blogs.cornell.edu/cornellmaple/aboutmaplesyrup/[↩][↩]
- The International Maple Syrup Institute. http://www.internationalmaplesyrupinstitute.com/uploads/7/0/9/2/7092109/maple_syrup_final_notice_pub_fr_1-29-15_01618.pdf[↩][↩]
- The International Maple Syrup Institute. http://www.internationalmaplesyrupinstitute.com/uploads/7/0/9/2/7092109/revised_u.s._standards_for_grades_of_maple_syrup_march_2,2015.pdf[↩]
- American Association for the Advancement of Science. Pure Maple Syrup: Nutritive Value.[↩]
- United States Department of Agriculture, Agriculture Research Service. USDA Food Composition Databases. https://ndb.nal.usda.gov/ndb/[↩][↩][↩][↩]
- The scientific basis of recent US guidance on sugars intake. Murphy SP, Johnson RK. Am J Clin Nutr. 2003 Oct; 78(4):827S-833S. http://ajcn.nutrition.org/content/78/4/827S.long[↩][↩]
- Diet, nutrition and the prevention of chronic diseases. World Health Organ Tech Rep Ser. 2003; 916():i-viii, 1-149, backcover. https://www.ncbi.nlm.nih.gov/pubmed/12768890/[↩]
- 2015–2020 Dietary Guidelines for Americans. https://health.gov/dietaryguidelines/[↩][↩]