03/25/2013 05:00 EDT | Updated 05/24/2013 05:12 EDT

Facts about maple syrup and how it's made

LONDON, Ont. - Some facts about maple syrup and how it's made:

— A handful of maple syrup producers still collect sap with buckets hanging on trees, while a network of plastic tubing and vacuum systems are becoming more popular on modernized farms. Some operations have equipment that use reverse osmosis to concentrate the sap's sugar content three or four times, which saves on the amount of time the sap must be boiled and produces a lighter-coloured syrup

— A maple tree reaches tapping size in about 40 years. A carefully tapped tree will yield, drop by drop, about two to five litres of sap on a warm spring day and could continue to provide sap for a century. An average maple tree will yield 35 to 50 litres of sap, which will produce one to 1.5 litres of maple syrup

— A healthy maple tree can be tapped when its trunk reaches 20 centimetres in diameter at 1.3 metres above ground level. Two to four taps per tree is common

— According to experts, sap that is collected represents only five per cent of total reserves in the roots and removing it does not damage the tree —

— Nutritionally, maple syrup contains about 65 per cent sucrose and one to two per cent glucose and fructose. It also contains potassium, calcium, iron, zinc, magnesium, manganese and riboflavin and is fat-free

Source: Agriculture and Agri-Food Canada