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The present study aimed to investigate the inhibition of in-package aerosolized aqueous antimicrobials against postharvest black mold caused by Aspergillus niger (A. niger) on apple fruit and in maintaining fruit quality. Apple fruit is susceptible to A. niger infection during storage, resulting in a significant decline in its quality. In this paper, the ability of chlorine dioxide (ClO2), Epsilon-polylysine (ɛ-PL), hydrogen peroxide (H2O2) and ozone (O3) to prevent and control Aspergillus infection in postharvest apples was evaluated. Results indicated that the treatments of 400 mg L−1ClO2, 500 mg L−1 and 1000 mg L−1 ɛ-PL could effectively alleviate the severity of postharvest black mold (A. niger) of apples and inhibit mycelial growth of A. niger. In addition, 0.5 mg L−1 O3 and 5% H2O2 also inhibited the mycelial growth of A. niger in treated apples. Further studies indicated that aerosolized ClO2 and e-PL increased corresponding defense-related enzyme activity and produced higher phenolic levels to improve disease-resistant of apples. Moreover, aerosolized ClO2, e-PL, H2O2 and O3 could be effective for maintaining quality of apple fruit during 24 days of storage at 20 °C. The present study gives a first insight into the A. niger control effect of in-package aerosolization technology associated with antimicrobials, which may be a potential method for the inhibition of A. niger on apple fruit.

Watercored 'Fuji' apple with special water core and unique flavor is a characteristic fruit. However, the problems of water core disappearance and browning in the apples are outstanding during postharvest storage. In this study, pulsed controlled atmosphere (pCA) with CO2 was used to protect the water-core and resist browning of apples. Effects of different concentrations of CO2 on the quality of apple fruits was investigated, and CO2 injury characteristic to apple fruits were studied as well. Results showed that pCA with CO2 could effectively maintain the sensory and texture qualities of watercored apples. Treated with pulsed controlled CO2, the degree of membrane lipid peroxidation of the apples was effectively reduced and the membrane system was well maintained. Meanwhile, the activity of polyphenol oxidase (PPO) and phenylalanine ammonia-lyase (PAL) of the apples were inhibited and the browning was reduced. On the whole, pCA with 1% CO2 presented the most significant effects on the quality preservation of watercored apples while higher CO2 showed negative effects on the quality of the samples. Under the condition of pCA with 5% CO2, the endurance of watercored apples was less than 45 days and the internal browning was serious. In conclusion, 2%～3% O2 and pCA with 1% CO2 was the best and most effective in the long-term preservation of watercored apples, and it is beneficial to guide for the preservation of apple fruits.

Physiological senescence and quality deterioration of peach after harvest were the restrict factors of peach shelf quality. As an ethylene inhibitor, 1-Methylcyclopropene (1-MCP) can effectively dealy fruit ripening and senescence, and improve storage quality. However, studies showed that the effect of fruit preservation by only using 1-MCP is unsatisfactory. Therefore, in this study, 1-MCP combined with sterilizing medium including ozone, TiO2 photocatalytic and epsilon-polylysine (e-PL) was applied for enhancement of preservative ability with safety and pollution-free. The flow microcirculation was used for enhancing the effect of sterilizing medium. Results showed that all these three treatment methods can enhance the shelf quality of peach fruit. Among them, the combination treatment of 1-MCP and ozone played a more active role in inhibiting decay, respiration, ethylene production, decline of nutrients such as organic acids and soluble solids. Moreover, it maintained bright color value and cell integrity of peach fruit. In addition, the combined treatment of 1-MCP and ozone had significant effects on inducing resistance in fruit and slowing down membrane lipid peroxidation. In conclusion, 1-MCP combined with ozone was an effective method to delay the senescence and improve the storage shelf quality of fruit, which is beneficial to the guidance of production practice and has potential application prospects in fruit preservation.