The actual composition, in exact quantities, of any given fruit is a variable unknown; even if it could be precisely determined it would not be the same in two consecutive seasons. Soil, situation, weather, type of tree, all have something to do with it. Even fruit of the same variety, grown under apparently identical conditions, would be found upon analysis to vary in their percentages of known elements.

Commercial producers are aware of this inconsis­tency; the grapes they grow on the same vines in the same soil are not identical in two consecutive seasons.

One might well ask - if this is true, how can two bottles of the same wine bought perhaps a year apart taste the same? Those two bottles of wine that seem the same may not be really; one may contain only two different wines whilst the other may contain many more. One can well imagine the patience and skill needed to blend several wines so that the result con­tains the characteristics that have made that particular brand popular.

Where home-grown fruit is being made into wine by the grower, he will think to himself, 'Well, it's been a dryish summer with plenty of sun; this means that there will be more sugar in the fruit this year.' There will be less sugar in fruit following a poor summer that has been rather wet. Accordingly he will adjust the amount of sugar by an ounce or so per pound of fruit used. Alternatively, he will follow the recipe to the letter and will not mind if there is a slight variation in two wines turned out with the same fruit and the same recipe. Obviously, if we use six pounds of fruit in one gallon of water we shall have slightly more sugar (fruit sugar) in the mixture than if we use only four pounds of fruit. And if the summer has been dry there will be more sugar than if it had been wet.

Since the sweetness or acidity of fruit can vary so much from year to year, obviously if you want to pro­duce the same result each time from the same recipe you must have some means of ascertaining the extent of the variation. This is where the hydrometer comes in. But first a word about sugar and acid.

The following table is not complete, but it is suffi­cient to show the reader that each fruit contains varied amounts of sugar and that the sugar content of each fruit varies quite a bit. The table, which may come in handy to those who want to experiment with using a hydrometer, is based on fruits grown under normal soil and weather conditions.

Fruit     Sugar content

%
Blackcurrants   7-8½

Gooseberries   3½—7
Strawberries    5-7½

Cherries 7½-12
Redcurrants 3-7

Whitecurrants    4½-5½

Blackberries 5½-6½

Raspberries   4½-8

Loganberries   4½-7
Apples   9-14½

Plums 4½-12

Different varieties of apples and plums might well con­tain amounts of sugar varying slightly from those above.

It is interesting to take gooseberries and strawberries as an example of how misleading one's palate can be when relied upon to compare the sugar contained in two different fruits. One might well suppose that straw­berries contain ten times more sugar than gooseberries, and to say: 'Well, then, gooseberries must contain more acid.* They do, in fact, but the difference is not so great as you would think.

The following table gives the approximate acid con­tent of some fruits grown under normal soil and weather conditions.

From the sugar table it will be obvious that, because we shall be diluting our juices, the actual amount of fruit sugar in the mixture will be very small indeed, and may, for all practical purposes, be disregarded for the time being. The acid content should be about right.

Now let us take grapes. Grapes, both black and white (and presumably those we call 'amber'), contain from fifteen to thirty-three per cent (possibly thirty-five per cent) of sugar. Because grape juice is rarely diluted a great deal, we must not overlook this high percentage of sugar. Nor must we overlook that gap between fifteen and thirty-three per cent.

It is here that the hydrometer comes in handy. Many people would call it essential, but I cannot agree: I have grown grapes and made good wine from them without a hydrometer. Yet I have found it useful, for it allows one to ascertain the exact amount of sugar contained in a must, so that the user can start with the same amount in consecutive brews.

Now, how much sugar should a must contain? Actually, there is no 'right' amount. Each type of wine will need a different amount of sugar; and even if the 'right' amount of sugar is in the must at the outset to produce that particular wine-type, it must not be over­looked that your own care, the extent of yeast action (one can never be absolutely certain at what point the yeast will stop working) and other factors bear upon the finished product.

In order to ascertain and control the amount of sugar in your must - the 'specific gravity' - you need a simple and inexpensive instrument, the hydrometer. This con­sists of a glass or plastic flask and a weighted float with a long, thin stem on which are marked the readings to be taken. A sample of the strained juice (or a specially strained sample if you are fermenting on the skins) is poured into the flask. This should be warmed slowly to 6o°F, and the float is then gently put in and allowed to float freely. The point where the stem sticks out of the liquid indicates the gravity of the must. Remember, however, when you are using a hydrometer, to take into account the surface tension of the juice. Where the stem sticks out of the liquid (see Fig. 3) the surrounding liquid climbs a little way up it. The reading should be taken where the liquid would have cut the stem if there had been no surface tension - i.e. you should ignore that slight rise just around the stem.

The gravity of water is 1-ooo (often written simply as 1 •). Our juices, even though diluted, will give a reading above this figure. How much higher will depend on the amount of sugar contained in the must. In the case of grape juice the ideal gravity would seem to be i*ioo; in a good year this reading might be attained without the addition of sugar.

A point to bear in mind here is that the decimal point is quite often dropped, so that a reading of 1150 is really 1•150. The more usual practice, however, is to drop the 1• and refer, for instance, to a reading of i•iio as ‘a gravity of 110’. This practice is now becoming general, and I myself always refer to my musts as having a gravity of 100 or no or 125 or whatever it may be.

When wine is made from fruits other than grapes there are other points to bear in mind; the main one being that we shall not be fermenting the pure juice or even a juice diluted only very little. More likely we shall be diluting our juices to as little as perhaps one-sixth of their original gravity - not to get more from our fruits but because it might be quite unpalatable if we did not. Naturally we want a nice wine, one well flavored of the fruit we are using and one with a com­fortable percentage of alcohol. But we do not want one so devoid of sweetness that when we sample it our tongues roll up, our cheeks cave in and our faces appear to be caught up in a vice.

Therefore, apart from using sufficient sugar to give the percentage of alcohol we want, we must also allow for some unfermented sugar to remain in the wine to sweeten it. It will be found that my recipes allow for just that, but since the amount of sugar in the fruit will vary from season to season, only with a hydrometer can you be sure that the must will always be the same.

A hydrometer reading from 1•ooo to 1•200 is best for the home wine-maker, for it allows him to take the gravity of musts above the 1•1oo mark. And since he will want musts containing sufficient sugar to produce about fourteen per cent of alcohol by volume and still have a little sugar left in the finished wine, he will need a hydrometer covering this range. Alternatively, he can use two, one reading from 1•ooo to 1•1oo and another reading from 1•1oo to 1.200.

surface -^tension

5. The Hydrometer, showing how to allow for surface tension*

Let us look at the following table. This is not com­plete, because we shall not want a wine containing less than nine per cent of alcohol, and it is unlikely that we shall be able to produce one above fourteen per cent, which is plenty (remember that we are talking about alcohol by volume and not proof spirit).

Specific  Potential

Gravity  Alcohol

%

1070 9•0

1080   10 •5

1090    11•9

1100   13 •4

1110   14 •5

Now, let us suppose we have taken the gravity of a must to which no sugar has yet been added and that the gravity is 1070. This would give us a wine containing nine per cent of alcohol. We decide that this is not enough and wish to make a wine of fourteen per cent. Therefore we must add some sugar.

Here it is useful to remember that two and a quarter ounces of sugar added to one gallon of must raises the hydrometer reading by roughly five degrees. As we want to raise it from 1070 to 1110—raise it forty degrees —we calculate: 'Five into forty goes eight times, so eight times two and a quarter ounces, or eighteen ounces, of sugar must be added.'

It may well be that a must containing as yet no added sugar might give a reading as low as 1020. In this event the reader may make a rapid calculation to find how much sugar is needed to raise it to 1110.

If we add just enough sugar to produce the amount of alcohol we want, the resulting wine will most likely be dry, since all the sugar will have been fermented out. This is a useful point to remember when a dry wine is required.

The amount of sugar that must remain in the wine to give it just that pleasant sweetness will depend on the palate of the individual maker, and he must calculate for himself, taking into consideration the type of fruit he is using.

The best plan for the beginner is to use a recipe and to take the gravity of the must (fruit-juice and water mixture) before adding the first lot of sugar. From this he will know how much sugar is needed to bring the gravity up to the point that will produce the amount of alcohol he wants. Having done this he will add the sugar needed and then allow fermentation to go on. After fourteen days he will add the second lot of sugar and take the reading again - making a note of each. As fermentation progresses he will take weekly (or more frequent) readings. When fermentation has ceased he will be able to judge whether slightly more or slightly less sugar should have been added.

When taking the gravity of musts that are fermenting, it is wise to shake the sample gently to release the carbon dioxide bubbles contained in it and to give the hydrometer a twist so that any bubbles clinging to it are also released. If this is not done, gross inaccuracies may occur. But for heaven's sake don't be afraid of the hydrometer: you will be surprised how ridiculously easy it is to use and understand. Once you have mas­tered it you will never regret it.

How Strong is My Wine?

Every home wine-maker wants a reasonably accurate answer to that question; and provided he is satisfied with reasonable accuracy he can test his wine at home and not be more than an unimportant point or two either side of precision.

On the other hand, if he cannot be satisfied, he will have to submit samples to test at a laboratory - or perhaps his chemist will test his wine for him. Either way he will have to pay, for testing involves distilling; and since two batches of wine are likely to vary in their alcoholic content, each would have to undergo a test.

The home wine-maker should not be tempted to distil a sample, for if he did he might well find that he has also distilled for himself a prison sentence (see pp. 86-87).

I do not propose to tell you how to distil; just let me say that when a sample has been distilled, this distillate is made up with distilled water and the gravity taken at 60°F. The reading is then compared with tables giving the percentages of proof-spirit against the rela­tive specific gravities.

In the following table, which is not complete, the reader will note that the readings are below the 1*ooo mark.

Specific   Proof-

gravity    spirit (%)

o•995 5•98

0•996 4•73

o•997 3•52

0•998 2•33

o•999 1•16

Note that the lower the reading the higher the proof-spirit - up to a certain limit.

Home testing with an instrument known as the vino-meter is quite simple; and since this is one of the most interesting aspects of wine-making, the reader should equipment. It is quite inexpensive (about 7s. 6d.) and simple to use; full instructions are sent with each instrument. Broadly speaking, all one has to do is to put a couple of drops of wine into the vinometer and then turn it upside down and take the reading. This will show the percentage of alcohol by volume. To arrive at the proof-spirit content compare the reading with the table on page 167.

Alcohol Degrees

by Vol. (%)   Proof-Spirit

8 13•9

9 15•6

10   17•4

11   i9•3

12   2I•6

13   22•7

14   24•5

15   26•2

16   28•0

4. The Vinometer, and some readings.

This method does not give complete accuracy, which can only be achieved by distillation.

Balance of Acid

One often hears the phrase 'correct acidity'. From the chemist's point of view there may be a ‘correct' amount of acid to have in a must at the outset or in a finished wine, but personal tastes are what matter most, and the skill in wine-making comes in making wines to suit your own palate.

As already mentioned, one needs laboratory experi­ence and test apparatus to determine correctly the acid content of fruit juices and the musts prepared from them, and this is likely to be beyond the scope of the average home producer. Nor is it necessary.

If we were going to ferment the pure juices, or juices diluted, say, by a quarter or half, we would need to determine the acid content - especially if the fruits we happened to be using were known to be rather high in acid - and adjust it. But our juices, and therefore the acid present, will be diluted to such an extent that the possibility of there being too much acid present in the must does not arise.

Nevertheless, many people who are fond of rhubarb wine admit that they would like it even more were it not for its acidity.

The oxalic acid in a must prepared from rhubarb is easily removed with pure medicinal chalk (precipitated chalk) obtainable from chemists. A quarter to half an ounce (not more) is worked into a smooth paste - a teaspoonful of must in a cup is ideal for this - and then stirred into the bulk. As it may take some time for the crystallized acid to settle, it is best to go ahead with making the wine as the acid crystals will be left behind in the lees at the first racking; this in most cases is at the fourteen-days stage. If the operator is not using Campden tablets and proposes to boil the juice, he will have to strain it first through two or three thicknesses of fine muslin to remove the acid particles.

One often hears of a wine being sharp, but otherwise a very pleasant drink, and that sweetening with sugar, although it improves matters, does not have the effect desired; there is still some sharpness, though this is less ‘biting’. It is a common belief that sugar will neutralize the acid in a fruit juice or wine. This is not so. Raw rhubarb or lemon dipped in sugar will still shrivel one's tongue; the same will apply, only a little less so, in a must or finished wine. You can apply the de-acidification tech­nique to a finished wine if you wish, with precipitated chalk as described above, but I have found that the flavor of the wine is usually impaired.

The remedy most easily applied is that of blending an acid wine with a non-acid wine. For example, if a wine is too acid and sugar makes no satisfactory differ­ence, the best plan is to blend it with a dried-fruit wine; these are usually lower in acid than other wines unless rather more acid than usual was added at the outset. Dried-fruit wines made with the recipes in this book will be low in acid and therefore ideal for blending with an acid wine.

The alternative to this is to use dates or raisins; one pound of either to a gallon of must prepared from fruits known to produce wines that are slightly 'tart', will put matters right.

Are You Ready To Move Onto The Next Lesson? Click Here...