Mild microwave treatments to reduce browning and extend shelf-life of fresh-cut artichokes

The objective of this work was to evaluate the effect of mild microwave (MW) treatments (spanning from 31 to 99 J g-1) as an alternative to chemical dipping to prevent post-cutting browning of fresh-cut artichokes. Artichokes (‘Madrigal’) were treated before or after cutting and then wrapped in polyvinyl chloride (PVC) film for 6 days of storage at 5°C. Quality parameters were analyzed including gas composition within the package, visual quality of receptacle and cut bracts (appearance score), color parameters, total phenol content, antioxidant activity and polyphenol oxidase activity (PPO). MW treatments (applied either on whole, before trimming, or on pre-trimmed artichokes) resulted effective in delaying browning and preserving post-cutting quality of fresh-cut artichokes compared to non-treated ones. Some differences were also noticed between the MW-irradiated samples with a slight better performance when treatment was made on the whole artichoke. When coupled with modified atmosphere packaging MW treatment still proved to be effective in delaying browning of cut surfaces. Results showed that application of mild MW treatments may reduce the browning potential of fresh-cut artichokes, contributing to maintain their quality attributes in order to allow a shelf-life duration suitable with the modern cold-chain distribution. Nevertheless, there are ample spaces for broader experimental approaches in order to optimize the treatment and to better clarify the thin border between the treatment effectiveness and the thermal damage on the product.