It is said that Indian syrup existed about 1600 years ago. Native Indians in Canada first discovered maple syrup, a sweet food with sweet taste, suitable sweetness, moistening lung and invigorating stomach, and used "indigenous method" to dig grooves and holes in maple trunk to collect maple juice. At that time, "Indian syrup" was the predecessor of today's "maple syrup" Winter in Canada is cold and long? There are no crops to grow during this period? Early Indians couldn't farm because of winter? They can only hunt and eat meat, lacking vitamins, minerals and other nutrients, and many people have died. Later, Indians gradually learned to make and eat maple syrup. Maple syrup provides rich nutrition and is an indispensable food for local Indians in winter. The picking process of maple syrup is very complicated, and the making process of maple syrup is also very complicated. March and April are the season of collecting maple sugar every year, and collecting maple juice requires a suitable temperature. Only when the temperature is lower than 0℃ at night and higher than 5℃ during the day can maple sap be extracted. The temperature of boiling maple syrup is generally kept at 4 degrees Celsius above the boiling point of water. The farmer drilled a hole about 5 cm deep in the trunk of a sugar maple tree over 40 years old, inserted a catheter, hung a bucket for collecting sugar maple sap, and let the sap slowly drip into the bucket. It takes about 30 liters to 45 liters of sap to extract 1 liter of maple syrup. A maple tree with a diameter of about 25 cm usually only needs to drill a hole, so it has the ability to recuperate and regain its vitality. Big maple trees for many years can generally drill 3-4 holes. According to the regulations of the federal government of Canada, maple syrup can be divided into three grades according to color, transparency and taste. The highest grade-with strong maple flavor, is most suitable for direct consumption; Grade II-slightly bad taste and amber color; The third grade-the deepest color, suitable for food additives. Maple syrup is usually eaten directly on pancakes. Another way to eat maple syrup is called "snow maple juice", that is, in winter in Canada, local people spread clean snow on clean wooden boards, pour boiled maple syrup directly on the snow, and the maple syrup will slowly solidify, and then slowly roll up the condensed soft maple syrup with a small stick to make a chewy maple candy lollipop.