Packaging, preservation and storage of the hottest

Packaging, preservation and storage of colored sweet pepper (I)

the production of colored sweet pepper in all seasons has strict requirements on the time to market, requiring a large number of products to be listed on festivals or packaged in supermarkets. In addition, most of the colored sweet peppers are produced and sold in other places. Therefore, while taking corresponding cultivation and management measures, it will make noise. After the colored sweet peppers are harvested, they should be packaged and stored by various means, which can not only delay the time of listing, centralize the supply to the market, but also facilitate the transportation in other places

after harvest, as in the growth period, colored sweet pepper is still carrying out life activities such as respiration, transpiration and growth. With the extension of storage time, it will lose weight, wilt and decline in quality. In the process of market transportation and circulation, it is relatively vulnerable to trauma and decay. To reduce the loss after harvest and maintain the freshness of products, we need to rely on various post harvest treatment technologies

section 1 physiological characteristics of colored sweet pepper after harvest

mastering the rules of physiological changes of colored sweet pepper after harvest is the fundamental to keep fresh, reduce decay and deterioration, and maintain its quality, flavor, color and freshness

(I) respiration

the colored sweet pepper after harvest is still a living organism and continues its metabolism. Respiration is the most basic physiological activity of fruit leaving plant organs. The respiration of the product continues after harvest, absorbing oxygen and discharging carbon dioxide through pores, lenticels, sepals and other parts. Only through slow respiratory and metabolic activities can the Postharvest colored sweet pepper fruits remain fresh. The respiratory matrix is mainly composed of carbohydrates and sugars, and is related to organic acids. This kind of matrix is decomposed and consumed by breathing. When breathing is vigorous, the matrix is consumed more, and the nutritional value decreases rapidly. Therefore, the quality must be correspondingly degraded. A solution using polymer thrust washers to replace metal needle roller bearings is also required. The strength of respiration is closely related to the environment in which the product is located. Therefore, no matter in the process of packaging and transportation, or in the process of storage, we should create an environment to reduce the respiratory intensity of colored sweet pepper fruits

during storage, the intensity of respiration is also changing. At the beginning of harvest, the respiration is strong, and then it gradually weakens. To a certain extent, it will be stabilized by spraying plastic on the lower surface

in the relationship between respiration and external environment, temperature has the greatest impact on respiration. The higher the temperature, the stronger the respiration; The lower the temperature, the weaker the respiration. When the temperature rises by 10 ℃, the respiratory intensity increases by 2-5 times. Therefore, low temperature treatment is the way to inhibit respiration. Because breathing will produce breathing heat, while the technical indicators of breathing lithium battery are developing rapidly, the thermal accumulation is bound to lead to the rise of temperature, which in turn will lead to the enhancement of breathing. Therefore, when picking colored sweet peppers that need to be stored, it should be carried out at the lowest temperature of the day

in addition, because respiration requires oxygen consumption, appropriately reducing oxygen partial pressure is also one of the important means of storing fresh scale. Generally, when the oxygen content decreases to about 2%, aerobic breathing is forced to stop. Therefore, as long as the oxygen content is higher than 2%, generally 3% - 6%, the respiration can be carried out slowly. However, it should be noted that the concentration of carbon dioxide should not be too high, otherwise it will cause physiological damage to the fruit of colored sweet pepper. The concentration of carbon dioxide should be controlled below 6%. Hydrated lime can be used to absorb excess carbon dioxide

(II) transpiration

the water content of colored sweet pepper fruit is about 93%, and the transpiration continues after harvest. The evaporation of water causes the direct loss of fresh weight of fruit during storage, and leads to fruit wilting, loss of fresh nutrients, and deterioration of flavor. At the same time, water evaporation and fruit wilting will cause premature senescence of protoplasm in fruit cells of colored sweet pepper, reduce the hydrophilicity and swelling power of colloid, and make the activity of enzymes in cells tend to hydrolyze, thus reducing disease resistance and storage resistance

the transpiration of colored sweet pepper fruit is related to the maturity of the fruit and the temperature and humidity of the external environment. The higher the fruit maturity is, the less water evaporates after harvest, and the evaporation of immature fruits is relatively large after harvest; The higher the air humidity is, the lower the temperature is, the less the water is, the lower the air humidity is, the higher the external temperature is, and the evaporation effect is strengthened. Therefore, in the process of packaging and storage of colored sweet pepper, create a lower temperature and higher humidity environment for the fruit

(III) after ripening

the fruit of colored sweet pepper is harvested from the plant, its growth effect is still in progress. After precooling, the fruits enter the post ripening period when they are stored. The essence of post ripening is that the tissue tends to physiological maturity and aging. During the post ripening process, due to the changes of various chemical components, the appearance and quality of colored sweet pepper fruits have also changed accordingly. Chlorophyll decomposes into pigments such as carotene and lycopene, which gradually turns the color of colored sweet pepper into red, yellow, orange or dark purple with uniform color