The insoluble product from currant pectin had the composition C 54.
It is pointed out that the composition of the pectin of white currants, as given in the preceding paper, is that of the typical lignocellulose, the jute fibre.
The time of cooking depends upon the per cent of pectin and the acidity of the juice; the more pectin and acid, the less the time of cooking.
A most satisfactory method of determining the quantity of pectin and consequently the quantity of sugar to use with fruit juice is suggested by the Bulletin of the National War Garden Commission.
Unless pectin is contained in the fruit, the addition of sugar to fruit juice will not cause the juice to jelly.
For jelly making, choose fruits which contain considerable pectinand some acid.
Add the liquid to the fruit juice deficient in pectinand use for jelly making.
If about 10 per cent of the fruit which contain much pectinis added to the other fruit, the flavor of the foundation fruit is not much altered.
The juice extracted for a third time from most fruits will contain enough pectin for jelly making.
If it is desired to use a fruit containing pectinbut deficient in acid, as sweet apple and quince, add tartaric or citric acid.
Pectin in the inner portion of orange and lemon peel.
Jelly is most easily prepared from fruits which are rich inpectin and contain some acid.
Pectin is like starch in that it stiffens when cold; but like sugar, in that it is soluble.
Long cooking of pectinchanges it into substances which do not have the property of jellying, hence, make jelly in as short a time as possible.
Nitric acid will convert this pectin into oxalic acid, or salts of sorrel.
It is associated with cellulose, and is converted into substances of the pectin group.
Such fruits as currants, crab apples and grapes contain much pectin and are, therefore, considered excellent jelly-making fruits.
There will be no tears shed over jelly that will not "jell" if all young housewives will learn the simple test for pectin; to find out whether a juice contains pectin or not is a very easy matter.
To make the pectin test add to one tablespoonful of cold cooked fruit juice one tablespoonful of grain alcohol.
If less than one-half forms a lump, add pectinto make the jelly, or can the juice for use as a beverage, flavoring, and so forth.
The pectin-alcohol test can be used here again to find out whether there is much or little or no pectin left.
If the pectin is slightly gelatinous or is less than three-fourths of the whole volume of juice, use less sugar.
Currants and unripe or partly ripened grapes are so rich in pectin that they require equal amounts of sugar and juice--that is, to every cup of extracted currant and grape juice we add one cup of sugar.
Make alcohol test for pectin to determine minimum amount of sugar to use, also the character of the fruit.
It is peculiar that this pectin frequently is not found in the juices of raw fruits, though it is very plentiful in the cooked juices.
An acid fruit is the most suitable for jelly making, though in some of the acid fruits, the strawberry, for example, the quantity of the jelly-making pectin is so small that it is difficult to make jelly with this fruit.
If the juice ferments, or the cooking of the jelly is continued too long, the pectin undergoes a change and loses its power of gelatinizing.
When equal quantities of sugar and fruit juice are combined and the mixture is heated to the boiling point for a short time, the pectin in the fruit gelatinizes the mass.
The peach does not contain so much free acid and it does contain a great deal of pectin bodies, which mask the acid; hence, the comparative sweetness of the ripe fruit.
This is especially important in jelly making for another reason also: In overripe fruit the pectin begins to lose its jelly-making quality.
Experiments have demonstrated that when sugar is dissolved and heated in fruit juice, if the sirup gauge registers 25°, the proportion of sugar is exactly right for combining with the pectin bodies to make jelly.
Pectin is at its best when the fruit is just ripe or a little before.
If thepectin is not in lumps, the sugar should be one-half or less of the amount of juice.
If the pectin is precipitated as one lump, a cup of sugar may be used for each cup of juice; if in several lumps the proportion of sugar must be reduced to approximately 3/4 the amount of the juice.
Fruits which contain pectin but lack sufficient acid are peach, pear, quince, sweet apple and guava.
These contain pectin and acid in sufficient quantities.
Jelly Making without Test The test for pectin is desirable, but it is not essential.
Pectin is a substance in the fruit which is soluble in hot water and which, when cooked with sugar and acid, gives, after cooling, the right consistency to jelly.
Measure juice and sugar in proportions indicated by the test forpectin or as directed under "Jelly Making without Test.
The pectin may be supplied by the addition of the juice of crab-apples or under-ripe grapes.
Test forPectin To determine if the juice contains pectin, boil 1 tablespoonful and cool.
The first pectin test should be saved for comparison with the others.
If the pectin collects in two or three masses, use 2/3 to 3/4 as much sugar as juice.
If the third extraction shows much pectin a fourth extraction may be made.
This is due to the fact that green grapes contain more pectin and, upon being cooked, produce fewer of the cream-of-tartar crystals usually found in grape jelly than do ripe ones.
After the juice and the alcohol have been mixed, pour the mixture slowly from the glass, noting how the pectin is precipitated.
Such juice, or juice that contains only a small amount of pectin, will prove unsuccessful in jelly making unless some substance or juice high in pectin is added to it.
All that has to be done in order to determine whether a certain fruit juice or combination of fruit juices will make jelly is to apply the test for pectin already explained.
It does not make jelly successfully in all cases unless some material containing pectin is added.
When the juice has been extracted from the fruit, it should be tested for pectin in order to determine whether or not it will be satisfactory for the making of jelly.
If, in the test for pectin, the addition of alcohol to the fruit juice does not turn the juice into a jelly-like mass, pectin is not present.
However, they do not contain pectin in sufficient quantity for jelly, so that when cherry jelly is desired, other fruit or material containing pectin must be used with the cherries.
Peaches contain so little pectin that it is almost impossible to make jelly of them unless some other fruit is added in rather large quantities.
Pectin is closely related to the carbohydrates, but as it does not yield heat energy nor build tissue, its food value is not considered.
If the fruit is a little under-ripe pectin is formed through cooking, and it is often advisable to add some green fruit to the ripe fruit in making jelly.
Nearly all failures in jelly making are due either to over-ripe fruit or to the use of too much heat, because in both cases the pectin is lost.
If the fruit is over-ripe the pectin breaks down into pectosic acid which has not the power of jellying; and as a result the fruit does not jell.
The above list will hopefully give you a few useful examples demonstrating the appropriate usage of "pectin" in a variety of sentences. We hope that you will now be able to make sentences using this word.
