Several fruit will quickly brown by oxidation, once peeled. To prevent this, simply dip the peeled fruit in a bath of water with ascorbic acid or lemon juice. When using an ascorbic acid solution, refer to the manufacturer’s instructions. The use of lemon juice is just as effective and much simpler, mix 1/4 cup (75 ml.) of lemon juice to 4 cups (1 L) of water.
The fruits are traditionally preserved in sugar syrup or juice. This method preserves the shapes, colors and flavors optimally. In the case of canned fruit, sugar is only used to enhance the flavor and appearance of products. It does not act as a preservative because the concentration is not hight enough. There is no indication against canning fruit without addeding sugar or use sugar substitutes.
There are many recipes to make syrup for canning fruit. The following table summarizes the four most popular.
The technique is always the same:
1 – Heat to dissolve sugar in water or juice.
2 – Add fruit and boil in the syrup until cooked.
3 – Pour the fruit into clean jars, leaving a space of 1/2 inch (13 mm.) at the top.
4 – Cover with hot liquid always keeping the 1/2 inch (13 mm.) of free space.
5 – Close the jars and process for conservation.
The vast majority of fruits can be process in a boiling water bath or by treatment in an autoclave (pressurized). Both methods are perfectly safe if properly used.
The following table shows the recommended processing time for the most popular fruits: