How the jujube is processed and stored

Henan Microwave Equipment Network News: We are a big country of jujube production. Because jujube is not durable to store and limited by technology, most of them are sold with fresh jujube and eaten with raw jujube. The processing rate of commodities is very low, and its embodied value and benefit can not be well reflected. With the continuous innovation of science and technology and the progress of storage and processing technology, the market demand for jujube and deep-processed products is constantly increasing. Therefore, the processing and storage technology of jujube is of great significance to the development of jujube market. Today we will discuss how to process and store red dates.

P>First of all, the harvesting and drying of jujube

The harvesting of jujube is usually in late September, but the harvesting time is different because of different edible and processing purposes. Jujube has thin skin and crisp flesh. It is easy to cause internal injury in picking and handling. Because these internal injuries are difficult to distinguish before storage, they are most likely to cause decay in storage. Therefore, it is strictly forbidden to knock or shake trees when harvesting, and to pick them by hand, so as to pick them lightly and put them lightly. After harvesting, jujube fruit should be classified according to its size to eliminate diseases, pests, deformities and injuries. Secondly, it should be pre-cooled, which is the necessary link to improve the fresh-keeping effect of jujube fruit storage. After harvesting, the temperature of jujube fruit should be lowered to about 0 C within 24 hours. The pre-cooling of jujube fruit can be carried out in the pre-cooling room of the cold storage or forced ventilation cooling. It can also be spread out in the cool and ventilated place for two or three days, so that the temperature of jujube fruit can be lowered to near the temperature of the storage room.

P>Date drying-Date drying refers to the dehydration and drying of jujube by means of a jujube dryer to remove the moisture in the pulp. Processing methods for increasing the concentration of dry matter to the extent that microorganisms are difficult to utilize. The commonly used processing methods are drying room, microwave drying, etc. In the process of drying jujube, attention should be paid to: (1) Before drying, jujube should be washed and then heat treated to destroy the activity of enzyme. (2) The baking temperature of jujube should not exceed 75 C in order to avoid the decomposition, coking and bitterness of sugar and other organic substances in jujube due to high temperature. (3) Jujube fruit is easy to crust under the condition of high temperature and low humidity, especially in the early stage of drying. Before packing, the crusted and cracked jujube should be picked out and packed in graded cartons with cushioned moisture-proof paper or wax paper. (4) The best storage temperature of dried jujube is below 0 C, but it is difficult to reach at 0 C under general conditions, so the jujube can be kept in a cold environment with air humidity below 65% and temperature around 5. When stacking jujube, there should be space and walkway to facilitate ventilation and operation.

and then the storage and preservation characteristics of jujube

The high respiratory intensity of fresh jujube is the basic reason for its post-harvest storage intolerance. At the same time, jujube has thin skin, undeveloped epidermis, easy evaporation of water and fast loss of water; jujube is particularly sensitive to carbon dioxide, and when the volume fraction of carbon dioxide in storage environment is higher than 2%, it will aggravate the softening browning of jujube. In addition, variety and maturity also affected storage. The results showed that late-maturing varieties were more resistant to storage than early-maturing varieties, fresh-eating and drying varieties were more resistant to storage than fresh-eating and drying varieties, cracking-resistant varieties were more resistant to storage than non-cracking varieties, small-fruit varieties were more resistant to storage than Large-fruit varieties; pear and jujube were generally resistant to storage, Jun and Huping jujube were less resistant to storage. Primary red fruit is the most resistant to storage, followed by semi-red fruit, whole red fruit is the least resistant to storage.

P>Fresh-keeping method of jujube

According to the actual storage conditions at the present stage, the fresh-keeping method of jujube fruit should adopt the fresh-keeping bag refrigeration method, and the air humidity in the fresh-keeping bag should be controlled in the range of 90%~95%. Fresh-keeping bags can eliminate harmful gases produced during the storage of fresh jujube in time. The bags are lined into plastic boxes, each box contains 10 kg jujube, tighten the mouth of the bags, and then stack and store. The temperature in the storage should be controlled in the range of - 1 ~0 C and the volume fraction of carbon dioxide should be less than 2%. In order to maintain a stable low temperature, the fluctuation of storage temperature should not exceed 1 C, and the fluctuation of jujube fruit temperature should not exceed 0.5 C. In this environment, jujube fruits can be stored for 60 to 100 days, and the rate of good fruit is 50% to 90%.

Microwave reminder: When choosing the drying equipment for jujube, we must choose the suitable drying equipment for jujube according to our own situation.