Key Technical Points for Jujube Fruit Harvesting and Post-Harvest Management

The harvesting period of jujube varies greatly depending on the intended use of the fruit and the cultivar.

1. Fruit used for candied jujubes: the white-ripe stage is the suitable time for harvest. During this stage, the fruit stops increasing in volume; the green color of the peel fades, turning milky white or greenish-white; the peel is thin and soft in texture, and after boiling it does not easily separate from the flesh; the flesh is relatively soft, with little juice and low sugar content, but it is rich in protopectin and highly resistant to boiling. The processed product is yellow-orange and crystalline, appearing amber and semi-transparent, chewy and smooth with no skin residue when eaten, offering a distinctive flavor.

2. Fresh-eating cultivars: harvesting at the crisp-ripe stage, when most of the peel has turned red to fully red, is preferable. For a small number of cultivars that accumulate sugar early, such as Zaozhuang crisp jujube, winter jujube, Jinsi Xin No. 4, etc., harvesting can be advanced to the white-ripe stage. During this stage, the fruit is brightly colored and beautiful, with a sweet and slightly tart flavor, crisp and juicy texture, and the best fresh-eating quality, as well as relatively good storability, making it the optimal period for picking fresh-eating jujube fruit.

3. The suitable harvest period for raw materials of processed products such as black jujube, southern jujube, jade jujube, and drunken jujube should be at the crisp-ripe stage when the peel has just fully turned red. At this time, the fruit stalk is green, the peel is fully or mostly colored red, the texture is thicker and slightly firm, and after blanching it easily separates from the flesh, with no sign of the flesh near the pit becoming soft or overripe. Fruits harvested at this stage not only yield a high proportion of finished products with good flavor, but also have a plump appearance; southern jujube has fine skin texture and a dark purple, glossy color.

4. The suitable harvest period for dried red jujube cultivars is best at the full-ripe stage. During this stage, about half a month after the peel has fully colored, the color further deepens to brownish-red or blackish-red, and the end where the fruit stalk connects to the fruit begins to turn yellow. The flesh changes from greenish-white to milky white, and the area near the pit turns yellowish-brown; the flesh texture gradually softens from near the pit outward, moisture content decreases, and natural fruit drop begins to occur. Harvesting at this time, the sun-dried red jujubes not only have a high drying ratio, but also have rich, vivid color, a plump fruit shape, and good elasticity, with the best quality.