Previously of sugar in Russia almost was not. The first small factory for processing of beet built in the province of Tula only in 1801 , and sugar coming in from abroad was so expensive that to use it for jam could not afford even the people are very wealthy. Often the sugar was replaced with honey. In the old days it was a lot, and it cost much cheaper imported sugar. But cooked and without honey, uparima berries until thick for 5 to 6 hours. Did it without an open flame, protopic Russian stove, which in a few hours "holds" quite a high temperature. Now, alas, the wonderful old furnaces do not meet often. But we humans are inquisitive and meticulous. Here's the recipe cherry jam without sugar at home, on the most ordinary kitchen. Those who love cherries, don't eat dessert, dieting, as well as those who simply counter sugar dedicated. I stumbled upon the recipe, I became terribly interested in it, tried it and was pleased with the result. Thanks for the recipe Yulenka(La Perla))