Irradiation for post harvest disinfestation has been
Irradiation for post-harvest disinfestation has been investigated for various fruits and vegetables and shows great promise since it sterilizes insects at low doses that are not enough to be detrimental to most fruits and vegetables [11,12]. The United States Department of Agriculture-Animal and Plant Health Inspection Services (USDA-APHIS), together with other international regulatory bodies, such as the International Atomic Energy Agency (IAEA) and the International Plant Protection Convention (IPPC), have issued guidelines for irradiation treatments to meet export and quarantine restrictions .
The benefits of using irradiation are that the cold treatment allows quality to be maintained without residue on the product, and reduces the use of fumigants and pallet loads can be treated at a time. Low dose gamma irradiation (1.0kGy or less) has been shown to control insect pests with little quality loss of fresh produce ; however, energy is imparted into metabolically alive tissues of the commodities and undesirable damage could occur . In 2006, the USDA-APHIS approved generic treatments of 0.15kGy for fruit flies and 0.40kGy for all insects except pupa and adult Lepidoptera . However, there are few reports on irradiation quarantine treatments in controlling pest mites. Similarly, the content of health-promoting compounds in citrus fruit may be altered by post-harvest treatments such as irradiation. For instance, recent studies showed that irradiation of citrus fruit significantly reduced the total ascorbic adrenergic receptors (TAA) content when irradiation doses were high [10,17]. However, information is still scarce on the effect of Co60-γ irradiation on nutritional quality of many citrus cultivars.
The objectives of this research were to evaluate the dose response of quality factors of Shatang mandarin to irradiation at 0.2-0.6kGy. Meanwhile, we found that the irradiation treatment can extend the shelf life and delay fruit senescence of the citrus fruits.
Materials and methods
Results and discussion
Conclusions Our results suggested that irradiation in the range of 0.2–0.4kGy in combination with refrigerated storage is an effective post-harvest technique in mitigating the risk of pests and decay of quarantined fruits.
Conflicts of interest
Introduction Natural antioxidants from fruits juices offer an alternative source of dietary ingredients to promote healthy life. For example, α-amylase, α-glucosidase inhibitors are considered as one of the effective measures for regulating type II diabetes by controlling glucose uptake, and acetylcholinesterase inhibitors are used to treat the Alzheimer\'s disease and tyrosinase inhibitors are clinically useful for the treatment of Parkinson disease [1–3]. In this research health relevant functionality of juice from indigenous fruit of Citrus hystrix and C. maxima (Red & White variety) is explored. Citrus fruits belong to the family of Rutaceae which is one of the most important fruits crops of the world and it is consumed mostly as fresh produce or juice because of its nutritional value and pleasant flavor. Citrus is an excellent source of many nutrients and phytoconstituents, and is able to supply a healthy diet. Phenolic acids and flavanones are the two main groups of phenolic compounds in citrus fruit juices . Generally, citrus juices are a rich source of antioxidant compounds, especially phenol, flavonoids and ascorbic acid . The phenolic compounds have a wide range of biological activities such as antioxidant activity, protection against coronary heart diseases, anti-inflammatory, anticancer and antimicrobial activities . C. hystrix DC (commonly known as Kaffir limeor wild lime) and C. maxima L. are giant citrus (commonly known as Pummelo) that are originated from South East Asia, India and cultivated throughout the tropical and temperate regions. C. hystrix is pear-shaped, bumpy, greenish yellow fruit with acidic flavor. It has a very thorny bush with aromatic leaves and fruits. The whole fruit is used in traditional medicine for headache, flu, fever, sore throats, bad breath and indigestion . These fruits are rich in phenolic compounds including flavonoids, glyceroglycolipids, α-tocopherol, limonoids, furanocoumarins, benzenoid derivative and quinolinone alkaloids with potential health-promoting properties [8,9]. These compounds have been proposed as important contributors to the radical scavenging activity. They showed variety of pharmaceutical effects such as anti-tumor, antimicrobial, anti-inflammation and antioxidant activities [9,10].