Method for preserving fresh dates at normal temperature

Abstract

The invention discloses a method for preserving fresh dates at normal temperature. The method mainly comprises the following steps of: carefully selecting the fresh dates, soaking the fresh dates in 70 to 80 percent of alcohol for 20 to 40 seconds or in 2 to 4 percent of sodium hypochlorite for 1 to 3 minutes, soaking the treated fresh dates in a preservative consisting of sodium nitroprusside, calcium chloride, tween 80 and water for 1 to 3 hours, fishing out the fresh dates, spreading in a thin and flat mode, air-drying, putting into a porous preservation bag, sealing, placing in a cool place, and storing at normal temperature. The method is low in preservation cost, and is economical, practical, safe and stable; during storage, the reddening rate and rotting rate of the fresh dates andthe content of soluble sugar and ethylene are reduced, and the content of vitamin c (Vc) and the activities of antioxidase, superoxide dismutase (SOD), catalase (CAT) and polyphenol oxidase (PPO) areimproved; and the storage period of the fresh dates is prolonged by 7 to 8 days.

Description

technical field [0001] The invention relates to the technical field of fruit preservation, in particular to a method suitable for preservation and storage of fresh dates at room temperature. Background technique [0002] Jujube is originally produced in my country. Its fruit is rich in nutrition, thin skin, crisp meat, sweet and sour taste, and has good fresh food characteristics. The content of vitamin C is as high as 300-500 mg / 100g, the content of soluble solids is 30%-36%, minerals and Rich in trace elements, and rich in cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP), it is very popular among consumers. However, fresh jujubes have thin skin, large flesh, high water content, and are not resistant to storage. After picking, they are only fresh and crisp for a few days in the natural state, and then the flesh will lose water, shrink, soften, and rot. There is a lot of vitamin C. Loss, usually after 6 days, the fruit firmness begins to declin...

AI Technical Summary

Problems solved by technology

This method plays a certain role in protecting the color and taste of winter jujube, but the crispness effect of fresh jujube is relatively poor.

Chinese patent 00136809.5 discloses a "preservation method for crisp jujubes". The technical point is to store fresh dates in a cold storage after being soaked in potassium permanganate solution, which can keep the crispness, flavor and taste of fresh dates for a long time. This technology Although the crispness and flavor of fresh jujube can be kept well, the storage conditions of preservation in cold storage are high, and the operating cost is high, which is unfavorable for large-scale promotion in production.

Chinese patent 200810054496.5 discloses "the fresh-keeping method of jujube", and the technical point is to process fresh jujube with a fresh-keeping liquid made of sodium chloride and white sugar, let the fresh-keeping liquid enter the fresh jujube, and then freeze at -5—-20°C for 3 -6 hours, this method forces the fresh-keeping solution to be injected or pressed into the fresh dates, which will definitely change the chemical composition of the fresh dates themselves and the taste of the fresh dates, so it is not a real physical fresh-keeping technology

In production practice, fruit merchants ask fruit growers to pick fresh jujubes when they have just entered the white-ripe stage. As a result, the taste of jujubes in the hands of consumers is poor, and they lose their crispness and nutrition.

Therefore, the purchasing power of consumers has declined significantly, seriously affecting the enthusiasm of farmers to develop fresh jujube varieties, and restricting the development of the fresh jujube industry.