Effects of Hot Air Treatments on Postharvest Storage of Newhall Navel Orange.

Chunpeng Wan,Jinyin Chen,Zengyu Gan,İbrahim Kahramanoğlu,Chuying Chen

doi:10.3390/plants9020170

Chunpeng Wan, Jinyin Chen + Show 3 more

Open Access

https://doi.org/10.3390/plants9020170

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Abstract

The effects of hot air flow (HAF) treatment on the postharvest storage of ‘Newhall’ navel oranges were investigated in this study. Studies were conducted with two separate sections. First of all, the effects of HAF at 37 °C for 36 h, for 48 h, and for 60 h were tested on fruit decay and weight loss. Thus, the optimal treatment was found as HAF at 37 °C for 48 h based on the fruit decay percentage and weight loss, and further studies were carried out with this treatment. The HAF-treated and control fruits were flowed at 37 °C and 20 °C with relative humidity (RH) of 85–95% for 48 h, respectively. After flowing, fruits of both treatments were individually film-packed, precooled (10–12 °C, 12 h), and stored (6 ± 0.5 °C and 85–90% relative humidity) for 120 days. Regular (0, 15, 30, 45, 60, 90, and 120 days) measurements were carried out for analyzing total soluble solid (TSS) content, titratable acid (TA) content, vitamin C (VC) content, total sugar content, respiration rate, malondialdehyde (MDA) content, and protective enzyme activities. The results indicated that HAF treatment significantly inhibited the MDA content and respiration rate of navel orange fruits after 45 d storage. The superoxide dismutase (SOD) and peroxidase (POD) enzyme activities were enhanced after 60 d storage, while polyphenol oxidase (PPO) enzyme activities were enhanced throughout the storage period. Results suggested that the SOD and POD activities are highly related with respiratory activities and could be enhanced with hot air flow. Meanwhile, HAF treatment maintained high content of TSS, total sugar, TA, and VC.

Highlights

Citrus is one of the most important fruit crops in the world, and best suited to grow in Mediterranean countries, China, and Brazil
Results of the present study showed that the hot air flow (HAF)
The main studies of the present study showed that HAF treatment prevents weight loss and fruit decay, and significantly improves total soluble solids (TSS), total sugar, titratable acidity (TA), and Vitamin C (VC) contents of navel orange fruits during cold storage

Summary

Introduction

Citrus is one of the most important fruit crops in the world, and best suited to grow in Mediterranean countries, China, and Brazil. The most important postharvest problems for the storage of navel oranges are reported to be weight loss, chilling injury, and decay incidence (caused by Penicillium italicum and P. digitatum) [2]. Among these three problems, pathogens are classified as a large cause of postharvest losses [3]. The global pressure from consumers about the use of synthetic chemicals encourages scientific studies to develop eco-friendly and safer alternatives to fulfill consumers’ demands and to reduce postharvest losses [5]. Low temperatures are highly effective in reducing weight loss (caused by respiration) and decay incidence; citrus fruits are very sensitive to low temperatures [9]. Suggested temperatures for orange storage are between 5 and 8 ◦ C [10]

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Conclusion