We have a small forest in our house, in which white birches grow.
During this period, when the snow melts and a large amount of water accumulates in the soil and the lowest temperature is around 0°C (32°F), the white birches in Hokkaido suck up a large amount of water for their own growth and store it in their trunks.
When a small hole of about 1 cm in diameter is made in the trunk, the water that is being sucked up seeps out as sap.
If the soil is rich in water and the birch is large, as much as 1 liter of sap per hour can be collected.
The sap is clear, with little or no contamination or turbidity. It contains natural xylitol in addition to several minerals. It is sweet to drink.
Xylitol, which is now used in confectionery and other products, was originally discovered in Scandinavia, where the custom of collecting sap was practiced. As a product ingredient, it is chemically synthesized.
In Hokkaido, it is said that the indigenous Ainu people drank xylitol during this time of spring.
Incidentally, if one tries to collect sap in other seasons, the amount is too small and the sap becomes cloudy, making it unsuitable for drinking as it is.
In Hokkaido, the sap is collected on a large scale in Mibuka Town, Asahikawa City, and Taiki Town.
Processed products are collected from all over Hokkaido and bottled at a facility in Mibuka Town.
I learned about sap from my own training as a tourist guide.
In Kenbuchi, it is collected at an alpaca farm in the town and offered to visitors as tea and other drinks.
I thought I would give it a try, so I went to a home improvement store, got some common tools, made a hole in the trunk of a birch tree, and stuck a tube in it.
I was amazed at how much came out.
I tried several different trees.
The thicker and taller trees produced a lot of sap.
You can drink the sap as it is.
It is slightly sweet.
I boiled it and drank it as Japanese tea, coffee, black tea, and herbal tea.
The sweetness seems to become stronger when heated.
The sweetness of the tea type goes well with beverages.
Black tea and herbal tea seem to go especially well together.
With coffee, the sweetness and bitterness clash, and the taste is divided.
We also tried it with alcoholic beverages.
Mild whiskey with water goes very well with it.
With shochu, we feel that the zing and sweetness of this drink do not necessarily go well together.
We also tried freezing the sap to make a water mix and it turned out to be sweet ice.
It is a very strange taste.
This year, we were only able to collect it and try several ways to drink it.
Next year, we will try sap collection tours (which we are doing in Mibuka Town) and sap-based confectionery making, etc., and will keep you posted.
