It is unnecessary to point out that low-grade fruit may often be used to advantage in the preparation of vinegar.  This has always been true in the case of apples and may be true with other fruit, especially grapes.  The use of grapes for wine making is an outlet which in now to be denied, and one alternative is the manufacture of vinegar from such grapes as are undesirable for eating.  The juice makes a very excellent vinegar, thought be some to be the superior to apple-cider vinegar.

VARIETIES OF VINEGAR

Vinegar may be prepared from any fruit juice or any other liquid containing sugar, or from a solution of alcohol.  The New York State law recognizes the following: apple vinegar or cider vinegar; wine vinegar or grape vinegar; malt vinegar; from in fusions of barley malt; glucose vinegar, from solutions for corn sugar or glucose; spirit vinegar or distilled vinegar, from dilute alcohol.  Vinegars have also been prepared from low-grade honey, waste oranges and peaches, and maple skimmings.  Exactly the same processes go on, no matter what the material from which the vinegar is made.  This publication is devoted to the preparation of vinegar from apple juice but whenever other fruit juices or sugar solutions are employed, similar rule and conditions prevail.

ACID IN VINEGAR

Whatever the fruit juice or liquid used in the preparation of vinegar, the acid or sourness is derived from the sugar in the material; other constituents in the juices contribute to the characteristic flavors, but from the sugar alone is acid eventually produced.

Two distinct steps are recognized and are necessary in the change fro sugar to acid.  These steps do not go hand in hand; on the contrary, it is important that the first be completed before the second begins.  In the first place small microscopic organisms called yeasts attack sugar, changing it to alcohol; in the second step, bacteria act on the alcohol changing it to acetic acid.

The sourness of the finished product and its power as a preservative depends upon the percentage of acetic acid obtained.  Vinegar of less than 4 per cent acetic acid is unsatisfactory.  It is also desirable that the product be of good flavor.  High acidity and excellence in flavor cannot be obtained unless the producer use intelligence at all stages,

from the selection of the fruit from which the juice is to be pressed until the vinegar is finally ready for use.  The process itself is simple so that no one need fear he is undertaking a complicated piece of work.  However, the few things that are necessary to be done must be done well.

MISTAKES IN VINEGAR MAKING

The usual methods of preparing vinegar on the farm in most cases will not give a product of marketable value and vinegar may even turn out to be so weak and of such poor quality that it is valueless for use at home in the preservation of vegetables.  Furthermore, the methods are sometimes wasteful.  A good cider capable of producing high-grade vinegar, may thru carelessness become transformed in such a way that it can never become vinegar.  Also there is great waste of time.  Altho a year may be required for the vinegar transformation, if some attention be given to the work a full-strength vinegar can be finished in a few months.  In many farm cellars there are barrels of vinegar more that two years old, which have not yet come up to full strength, and which indeed, may never reach 4 per cent acidity.

Usually a farmer places his fresh sweet cider in an old vinegar barrel and rolls it into the cellar.  He then expects that, without giving it further attention he will have good vinegar next year.  There is but little chance that his expectations will be realized.

It has been the custom on some farms to add low-grad molasses to the barrels of sweet cider and set them in the sun during mild weather in a warm room in winter.  This almost always giver vinegar of the required strength, but the use of molasses is not alone expensive but also unnecessary since equally good results may be obtained by careful methods.

From The Preparation of Marketable Vinegar by Frank E. Rice – Cornell Extension Bulletin #40, April 1920 published by the New York State College of Agriculture at Cornell University, Ithaca, New York. 

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