The amount of sugar depends upon a number of factors such as soil, climate, culture, variety, and ripeness, unripe and over-ripe apples containing less sugar than ripe ones.
[[+]] Browne has shown very clearly the changes that take place in the sugar content of apples at different periods of ripeness:
[[+]] Browne, Annual Rept. Penn. Dept. Agr, 1899. p. 541.
Table II —— Sugar in Baldwin Apple at Different Periods.
| Date | Condition | Equivalent of Total Sugar in Form of Invert Sugar. |
|---|---|---|
| Aug. 7, 1899 | Very Green | 8.11 |
| Sept. 13, 1899 | Green | 10.72 |
| Nov. 15, 1899 | Ripe | 14.87 |
| Dec. 15, 1899 | Over-ripe | 14.85 |
The question is sometimes asked whether the so-called "sweet apples" will make as good vinegar as the tarter varieties. All things being equal, there is no reason why they should not, provided they contain as much sugar as the more acid kinds. This statement may seem somewhat paradoxical, but it should be remembered that [Page 8] it is the presence of acid rather than the absence of sugar that makes an apple taste sour. As a matter of fact, some of our very sourest sorts contain as much and more sugar than the sweetest sweet apples. Cider for vinegar should not contain less than 8.5 per cent. of sugar.
Storage of the Cider.
The most satisfactory containers for both cider and vinegar are whisky and brandy barrels. Molasses barrels and old vinegar barrels should be used only when no others are available, and then not until they have been very carefully and thoroughly cleaned. Too much stress cannot be laid upon the necessity of scalding old vinegar barrels with either live steam or boiling water to remove the last trace of the old vinegar. There is, perhaps, no one factor which is responsible for more failures in farm vinegar making than the time-honored but pernicious custom of using old vinegar barrels for sweet cider without even rinsing out the dregs of former years. Mere rinsing is not sufficient. They must be scalded to make them fit for use. If this is not done in such a manner as to kill all of the organisms in the barrel, the probability is that the sweet cider which is put in them subsequently will never make vinegar. The reason for this will be given a little later. In a recent number of a certain farm journal, the following is given under directions for making apple vinegar:
"Get a barrel in which good vinegar has been made and use it, or get some of the scum off of the top of good vinegar and rinse out the new barrels with this as soon as they cool after having been thoroughly washed out with boiling water. Put fresh cider into these barrels."
No procedure more absurd and dangerous to the success of apple vinegar could possibly be undertaken than is contained in this recommendation. In fact, it would be difficult to find a better recipe for vinegar failures than this. Never, under, any consideration, put either "mother" or old vinegar into sweet cider. It is never safe to use metallic containers for holding cider even for an interval of a few hours, since the acid of the juice attacks the metal, dissolving a portion of it. Such cider, because of the metal in solution, might produce metallic poisoning in the person drinking it.