After the fruit has been prepared and while the containers, etc. are being sterilized, it is necessary to prepare the sirup that is to be used. For the sweet fruits of Group 1, No. 1 or 2 sirup should be made; for the sour fruits of this group, No. 2 or 3 sirup; and for the very sour fruits, No. 4 or 5 sirup. The hard fruits may be canned by this method with No. 1, 2, or 3 sirup, while the special fruits require No. 4 or 5 sirup. If the fruit is to be canned for pie, it will be advisable to use thin sirup and then use more sweetening when pies are made.
When the sirup is made by mixing the sugar and water and bringing it to a boil, the prepared fruit should be dropped into it and cooked. The fruit should be cooked in the sirup until it may be easily pierced with a fork or until it is soft. Berries have to be cooked only a few minutes, while the hard fruits may require from 10 to 15 minutes. The jars should be placed upright in a pan of hot water while the boiling fruit from the kettle is poured into them, and as each jar is filled the rubber should be put in place and the cover adjusted and secured. It is important to close one jar before filling another, because the longer a jar remains open the more bacteria will be permitted to enter. Even by working as rapidly as possible and taking the greatest precaution, a certain number of bacteria are bound to enter in this method of canning. After the jars are filled and sealed, they should be placed upside down or on the side to cool and test for leaks.
85. If the cold-pack method is employed in canning fruit, it is possible to obtain a sterilized product that is dependent for preservation on neither the sirup used nor the acid of the fruit. In this method, the jars, jar tops, covers, and utensils for handling the fruit do not have to be sterilized beforehand. They may simply be washed clean and kept hot in clean water until they are needed. After the fruits are prepared, some are blanched or scalded and cold-dipped, while others are not. They are then packed into jars and boiling sirup is poured over them. Then the rubbers are adjusted, the covers placed on, but not made tight, and the jars are placed under water in the water bath or on the racks in the pressure cooker, which should contain a small amount of water, as has been explained. After cooking the required length of time, the jars of fruit are removed from the cooking utensil, sealed, and allowed to cool.
The sirup used in the cold-pack canning method may be heavier in each case than that mentioned for the open-kettle method, because there is no evaporation, as is the case where fruits are boiled in the sirup before they are placed in the cans, but less will be required if the packing is well done.
GROUP 1--SOFT FRUITS
86. SWEET SOFT FRUITS.--The sweet fruits included in Group 1 --blackberries, huckleberries, elderberries, ripe gooseberries, mulberries, raspberries, and sweet cherries-may be canned in exactly the same way, so that the same general directions will apply to all. Prepare the different kinds of berries, which should be as fresh as possible, by looking them over carefully and removing the poor ones, and then washing them. To wash them, pour them into a colander and dip it up and down in a large pan of clean, cold water. The less handling such fruits receive, the more perfect will they remain for canning. Prepare sweet cherries, which should be procured with the stems on if possible, by first washing them and then stemming them. They may be pitted, or seeded, or they may be left whole, depending on personal preference. Cherries that are not pitted will keep their shape and have a good appearance, but they are not so convenient for eating as those which have been pitted.
87. After the fruit has been prepared in the manner just explained, pack it closely into the hot, clean jars, using a spoon for this purpose and turning each jar as the fruit is poured into it. Press the berries or the cherries down carefully, so that 2 quarts of them will fill a 1-quart jar. Then proceed to make the sirup. As these fruits are the sweetest, they require less sugar than any other. If such fruit after it is canned is to be used for pie making, sirup No. 1 or 2 will be suitable, but if it is to be used for sauce, No. 3 sirup may be used. When the mixed sugar and water is boiling rapidly, pour it over the fruit packed into the jars. Then place the rubbers, adjust the jar tops, and proceed to sterilize and cook the cans of fruit. Boil these in the water bath for 15 minutes, or cook them in the pressure cooker for 8 minutes at a pressure of 5 pounds or for 4 minutes at a pressure of 10 pounds.
88. SOUR SOFT FRUITS.--Of the sour fruits, STRAWBERRIES, GRAPES, and CURRANTS require about the same quantity of sugar, that contained in sirup No. 3, 4, or 5 usually being sufficient. Otherwise, the canning process, including the length of time for processing, does not differ materially from that just given for sweet soft fruits.
In the case of strawberries, those which are of medium size and rather dark in color are best for canning; in fact, very large, light-colored strawberries will shrink more than any other kind. The berries are washed in the same way as other berries, but they should not be allowed to stand in water for any length of time, because this will tend to make them soft and mushy. Strawberries must be stemmed after they are washed, and for this purpose a strawberry huller should be utilized. Such a device, which is shown in Fig. 1, permits the stems to be removed without crushing the berries and soiling the fingers.
In preparing currants for canning, the procedure is the same as for the fruits already mentioned; and the same thing is true of grapes that are not to be seeded. If the seeds are to be removed, however, the procedure up to getting the cans of fruit ready for processing is different, as is here pointed out. After washing the grapes, squeeze the pulp from the skins and then cook it in a kettle for a sufficient length of time to make it soft. Remove the seeds by forcing the pulp through a sieve. Then add as much sugar as would be used for making the required sirup, and cook until the sugar is dissolved. With this done, add the sweetened, seedless pulp to the grape skins and fill the jars with this mixture. Then continue the canning process as for the other fruits of this group.