Colour and Flavour
Most school children in Canada learn that the maple syrup they put on their pancakes is made by boiling the sap from the sugar maple tree to one-fortieth of its original volume, but there is more to it than that.
If the water is removed from maple sap by freeze concentration or by vacuum rather than by boiling, the maple flavour is absent and the colour of the syrup is rather gray. But once the syrup is heated a golden brown colour and maple flavour develops. Heat is therefore one of the critical ingredients of maple syrup. Related truths to maple syrup production include: syrup colour and flavour is lighter at the beginning of the season than the end; the longer sap is boiled the darker the colour and the stronger the flavour.
This non-enzymatic development of colour and flavour from the complexation of amino acids with invert sugars in the presence of heat was described in 1912 by Louis-Camille Maillard of France. It begins at temperatures of 80°C and below being much different than caramelization which occurs at 110°C for fructose and 160°C for glucose and sucrose.
Indian legends of how the sugar maple produces its sweet sap and why it is available for only a few weeks a year make for fascinating reading and instill the values of hard work and care for nature.
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