Physical method for preserving freshness of waxberry fruits

Abstract

The invention discloses a physical method for preserving the freshness of waxberry fruits. The method includes the following steps: 8 to 9 ripe waxberry fruits are sequentially processed by sterilization, precooling, anaerobic pretreatment and packaging and then are stored at the temperature from 0 to 2 DEG C, wherein the treatment of sterilization is 8 to 10 minutes of air-tight ozone treatment with concentration ranging from 2 to 4 mg / m<3>; the precooling treatment lasts for 15 to 20 minutes at the temperature ranging from 0 to 5 DEG C under the vacuum pressure ranging from 0.06 to 0.08 MPa; the anaerobic pretreatment adopts nitrogen flow with the concentration ranging from 98 to 100 percents and is continuously carried out for 15 to 20 hours; and the packaging adopts PE perforated filmbags. The method of the invention belongs to physical methods for preserving the freshness, dispenses with any preservative or other chemical agents, is safe and environmentally friendly, and can be popularized and applied to fruit growers, sales persons and manufacturers; and the storage period of the obtained waxberry fruits can reach 15 days, the rot index is lower than 10 percents, and the nutrient contents, such as Vc and the nutritive index thereof can also be favorably maintained.

Description

technical field [0001] The invention relates to the field of fresh-keeping of fruits and vegetables, in particular to a physical fresh-keeping method of bayberry fruit. Background technique [0002] Waxberry is a specialty fruit in my country, and its cultivation area accounts for more than 99% of the world's total, mainly distributed in Zhejiang, Jiangsu, Fujian, Guangdong and other provinces. Red bayberry fruit is favored by consumers because of its bright color, sweet and sour juiciness, and strong flavor. But red bayberry is a fleshy berry, and the fruit has no exocarp protection, so it is very vulnerable to mechanical damage. The harvest period is high temperature and rainy season, and the respiratory intensity of red bayberry is high after harvesting. It is very difficult to store and transport, and the normal temperature shelf life is only 2-3d ( Days), so there is a saying that "the taste changes in one day, the color changes in the next day, and the quality changes...

AI Technical Summary

Problems solved by technology

[0005] Therefore, at present the storage and fresh-keeping methods of bayberry fruit mainly contain: 1. low-temperature preservation: harvest the bayberry of storable varieties, store at 0~2°C, and rotten fruit will appear on the 9th day after storage, and the short-term storage of bayberry can be realized by low temperature method , but to achieve longer storage and transportation must be supplemented by other means

②Chemical agent fresh-keeping method: use 0.1% salicylic acid solution, or soak fruit in a mixed solution of CaCl2 and naphthalene acetic acid with different concentrations, which can reduce fruit rot, but chemical agent storage and preservation are easy to cause Toxic residues are harmful to human health. At the same time, the problem of drug resistance caused by chemical antiseptic treatment also makes chemical prevention and control technology face severe challenges.

③Traditional nitrogen filling and MAP (Modified-Atmosphere Packaging) spontaneous modified atmosphere storage: select fruits without mechanical damage, put them in plastic bags with a certain thickness, fill them with 85% nitrogen, seal them, and store them at low temperature. It has a certain effect on controlling the aging and rot of bayberry fruit, but MAP controlled atmosphere storage mainly relies on the respiration of fruits and vegetables and the air permeability of the film to adjust the gas concentration in the packaging bag. It is difficult to maintain the suitable atmosphere environment required by fruits and vegetables. At the same time, due to the use of sealed film bags, the phenomenon of "condensation" is easy to occur in the film bags due to the influence of fruit respiration, which provides a good environment for the reproduction and infection of microorganisms. possible

[0009] (1) The bactericidal effect of ozone is greatly affected by temperature and humidity, and different fruits and vegetables have different requirements, which limits the use of ozone; (2) When fruits and vegetables are in sealed packaging, the effect of ozone preservation in cold storage is not ideal, so the development of effective The ozone fresh-keeping packaging method is imperative; (3) The development of complete sets of ozone generator equipment is slow, resulting in the limited application of ozone in the fruit and vegetable preservation industry; (4) High-concentration ozone has harmful effects on human eyes, skin, and respiratory tract

At the same time, high concentration of ozone will reduce the quality of fruits and vegetables

[0010] Furthermore, the Beckerson study states that 【1】 , a higher concentration of ozone will increase the relative conductivity of fruit and vegetable cell membranes, and chlorophyll and carotenoids will also be easily damaged

Gao Qingyi et al 【2】 It is also pointed out that when fresh fruits and vegetables are preserved, if the ozone concentration is used improperly, it will cause damage to the fruit and vegetable cells, increase their permeability, and cause extravasation of cell contents, resulting in quality degradation or spoilage.

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