UV-C Treatment of Apple and Grape Juices by Modified UV-C Reactor Based on Dean Vortex Technology: Microbial, Physicochemical and Sensorial Parameters Evaluation

ABSTRACT Knowing that moderate stress such as UV radiation can activate defense mechanisms in plants, the use of UV-C radiation appears as hypothesis of a promising technique that would help to stimulate and enhance beneficial compounds for health, through a clean and healthy technology. In this study, the possible induction of secondary metabolism, the increase in the content of phytochemical compounds and physicochemical changes through the use of UV-C radiation were evaluated on whole grape juices produced with Vitis labrusca grapes, cultivar Isabel Precoce. Grapes were harvested, sanitized, exposed to UV-C radiation at doses of 0, 2, 4 and 6 KJ m-2, and then the juices were prepared and packed into amber glass bottles at room temperature. Analyses were performed at 0, 30, 60, 90 and 120 days of storage. Based on results obtained and conditions in which the experiment was performed, UV-C treatment in grapes caused abiotic stress in the fruits, affecting color, titratable acidity, soluble solids/titratable acidity ratio, vitamin C and percentage of protection against oxidation. Application of UV-C did not change levels of phenolic compounds in fruit juices or the percentage of scavenging free radicals, pH and soluble solids.

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Effect of UV-C and UV-B treatment on polyphenol oxidase activity and shelf life of apple and grape juices

Innovative Food Science & Emerging Technologies ◽

10.1016/j.ifset.2014.05.014 ◽

2014 ◽

Vol 26 ◽

pp. 498-504 ◽

Cited By ~ 49

Author(s):

Alexandra Müller ◽

Laura Noack ◽

Ralf Greiner ◽

Mario R. Stahl ◽

Clemens Posten

Keyword(s):

Shelf Life ◽

Polyphenol Oxidase ◽

Oxidase Activity ◽

Polyphenol Oxidase Activity ◽

Grape Juices ◽

Uv C

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QUALITY CHARACTERISTICS AND ANTIOXIDANT ACTIVITY OF JUICES PRODUCED WITH IRRADIATED GRAPES

Revista Brasileira de Fruticultura ◽

10.1590/0100-29452017188 ◽

2017 ◽

Vol 39 (2) ◽

Author(s):

ANA CAROLINA VILAS BOAS ◽

RITA DE CÁSSIA MIRELA RESENDE NASSUR ◽

JULIANA MESQUITA FREIRE ◽

ANTÔNIO DECARLOS NETO ◽

LUIZ CARLOS DE OLIVEIRA LIMA

Keyword(s):

Antioxidant Activity ◽

Vitamin C ◽

Grape Juice ◽

Physicochemical Characteristics ◽

Total Phenolic ◽

Radiation Doses ◽

Steam Extraction ◽

Grape Juices ◽

Uv C ◽

Different Doses

ABSTRACT The aim of this study was to evaluate physicochemical characteristics, antioxidant activity, total phenolic, vitamin C and anthocyanins content of grape juices from cv. Isabel submitted to different UV-C doses. The fruits were harvested, sanitized and inserted into a UV-C radiation chamber, where different doses were applied: 0 kJ/m2 (0 minutes); 0.68 kJ/m2 (2 minutes); 2.73 kJ/m2 (4 minutes); 4.10 kJ/m2 (6 minutes). The grape juice was extracted at 75±5°C for 1 hour, using an equipment with steam extraction and submitted to evaluations after 0, 30, 60 and 90 days of cold storage. No significant differences were observed in grape juices submitted to radiation doses regarding the antioxidant activity and phenolic compounds. However, the vitamin C content was affected by different UV-C doses, where there was an increase in the values of the treated fruits during storage.

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