1. Raw material requirements The raw materials for making preserved fruits and candied fruits are required to have dense flesh, resistant to cooking, ripening and non-transitional, and the flesh maintains a certain degree of hardness, but there are different requirements for different varieties. For example, the production of dried apricots fresh apricots require golden color, delicate flesh, with toughness, maturity is not soft and not sheep, easy to leave the core, storage varieties.

2. Pretreatment. Formation of preserved fruit unique flavor is the key to fine work. The production of preserved fruits and candied fruits selected after a series of pretreatment, is the material basis for product quality and prerequisites. For example, the processing of apricot preserves of fresh apricots to dig the nucleus process.

3. Fumigation. Fumigation method, generally will be pre-treated raw materials on the drawer, and iron bowl of sulfur in the vat or cement pool at the same time, ignite sulfur with a quilt or sack cover for fumigation, but also in the special fumigation room fumigation. The amount of sulfur is generally 0.2 to 0.3% of the raw material, fumigation time depends on the size and nature of the fruit, generally 30 to 60 minutes. Can also be used 0.5 ~ 0.6% concentration of sodium bisulfite solution immersion instead of fumigation. Sulfur fumigation or sodium bisulfite immersion can prevent the fruit tannin material is oxidized, to maintain the bright yellow or golden color and maintain the vitamin C, at the same time, sulfur dioxide dissolved in sugar solution can also prevent the sugar solution fermentation and so on.

4. Sugar cooking. The processing principle of preserved fruits and candied fruits is based on the high concentration of sugar liquid preservation. In the process of sugar boiling, so that the flesh of the fruit into a large amount of sugar, discharge water. Sugar concentration to reach 60 ~ 65%, with a great osmotic pressure, so that the microbial body of water by the sugar precipitation, in a dehydrated (physiological drying) state and be inhibited. Therefore, dried fruit preserves are not easy to deteriorate even if they are not sealed. Sugar impregnation can also prevent the oxidative loss of vitamin C in the fruit, and can improve the flavor of the finished product. But too much sugar, too much sweetness will affect the original flavor of the finished product. Therefore, the sugar content of the finished product is required to achieve the purpose of anticorrosion and dehydration, but also to maintain the flavor characteristics of the product, in order to be just right, which is the key to the processing of preserved fruit.

Cooking of preserved fruits and candied fruits is divided into a cooking method and multiple cooking.