Optimization of the Appearance Quality in CO2 Processed Ready-to-Eat Carrots through Image Analysis

Summary

A high-pressure CO2 process applied to ready-to-eat food products guarantees an increase
of both their microbial safety and shelf-life. However, the treatment often produces unwanted changes
in the visual appearance of products depending on the adopted process conditions. Accordingly,
the alteration of the visual appearance influences consumers’ perception and acceptability. This
study aims at identifying the optimal treatment conditions in terms of visual appearance by using an
artificial vision system. The developed methodology was applied to fresh-cut carrots (Daucus carota)
as the test product. The results showed that carrots packaged in 100% CO2 and subsequently treated
at 6 MPa and 40 ◦C for 15 min maintained an appearance similar to the fresh product for up to
7 days of storage at 4 ◦C. Mild appearance changes were identified at 7 and 14 days of storage in the
processed products. Microbiological analysis performed on the optimal treatment condition showed
the microbiological stability of the samples up to 14 days of storage at 4 ◦C. The artificial vision
system, successfully applied to the CO2 pasteurization process, can easily be applied to any food
process involving changes in the appearance of any food product.