Effect of ozone on the quality of fresh-cut green beans (Phaseolus vulgaris L.)...

• Author(s): Alexandre, Elisaberte M. C. ; Fundo, Joana ; Santos, Dora M. ; Brandão, Teresa R. S. ; Silva, Cristina L. M.
• Date: 2005
• Persistent ID: http://hdl.handle.net/10400.14/6165
• Origin: Veritati - Repositório Institucional da Universidade Católica Portuguesa
• Subject(s): Ozone; Quality; Fruits; Vegetables
• Document Type: Conference Object
• Language: English

Description

Ozone is a potent oxidant and disinfectant agent with multiple industrial applications. The efficacy of ozone treatments has been recognised in the sanitation of equipments and water disinfections. Recently, ozone started to be used as an innovative food processing technology that guarantees product safety. The objective of this work was to study the effect of ozone on the quality of fresh-cut green beans (Phaseolus vulgaris, L.) and green and red bell peppers (Capsicum annuum, L.). The quality factors analysed were enzyme (peroxidase) activity, colour and texture for green beans, and colour, texture and pH for bell peppers. Experiments were carried out in pilot equipment. An ozone generator was interconnected to a container filled with tap water. Ozone was continuously incorporated in water and its content was indirectly measured by potential difference. Green beans and bell peppers were cut in small portions. Samples were immersed in ozonated and non-ozonated water baths and removed after different times till a maximum of 180 minutes. Data from both treatments were compared by analysis of variance. For green beans, results showed that ozone treatment did not affect the colour, but significantly influenced texture (firmness) and peroxidase inactivation (at 7% significance level). After 40 minutes enzyme activity was reduced approximately 20%. This inactivation was verified for the rest of the sampling times. Ozone treatment affected pH and texture (fracturability) of red bell peppers (at 1% significance level). The other quality factors were not significantly influenced by ozone.