Effects Of UV-C On Ox Horn Pepper Fruit Shelf-life And Its Mechanism

Ox horn pepper (Capsicum annuum L.,var. lengum Bailey,cultivar"Big-fruit 99") fruit was taken as test material in the experiment, and common ultraviolet germicidal lamp with wave length 254 nm was used as the radiation source. The amount of radiation dose at the site 36cm from the lamp measured by ultraviolet ray strength measuring meter was 0.2 mw/cm2. The fruit was radiated with different doses ( 0.0, 0.7, 0.9 and 1.0 kJ/m2), and then stored at room temperature around 25℃. The best radiation dose was drawn through sensory indexes. Ox horn pepper's nutrition indexes including soluble solids content and vitamin C content, physiology indexes including relative membrane permeability and MDA content, and protective enzymes activity were measured based on the best treatment. The paper has discussed the feasibility of UV-C irradiation treatment for prolonging the storage period of ox horn pepper at room temperature, explored the physiological mechanism, and provided a practical technology to extend ox horn pepper fruit's commercial life in their storage, transportation and sale. The main results showed that:(1) UV-C treatment could ameliorate the appearance of the horn pepper in the storage period. The dose of 0.9 kJ/m2 was the best treatment in this test.(2) The optimal doses of UV-C treatment could significantly reduce the ox horn pepper nutrient loss. The content of soluble protein and reductive vitamin C were higher than the control.(3) Treatment of 0.9 kJ/m2 could maintain chlorophyll content, restrain respiration rate, improve the protective enzymes'activity, clean radical and reactive oxygen species, reduce the accumulation of MDA, and reduce the damage of the cell membrane system, extending shelf-life at room temperature around 25℃.