Invited review: Engineering aspects of physical treatments to increase fruit and vegetable phytochemical content

Abstract

Vigneault, C., Leblanc, D. I., Goyette, B. and Jenni, S. 2012. Engineering aspects of physical treatments to increase fruit and vegetable phytochemical content. Can. J. Plant Sci. 92: 373–397. The levels of phytochemicals in fruit and vegetables are affected by many preharvest and postharvest factors, such as cultivars, farming practices, environmental conditions, harvest techniques, and postharvest handling and treatment. Postharvest factors are generally the easiest to manage since produce handling takes place mainly under controllable conditions. Although specific physical treatments, such as heat and ultraviolet radiation, have been developed to increase the phytochemical content of horticultural produce, very little information is available on the engineering aspects of these treatments. A review of the engineering aspects related to phytochemical-enhancing physical treatments was undertaken to identify the process parameters required to obtain repeatable results, the basic information required for scale-up of the process, and the key parameters required to ensure appropriate monitoring and control of commercial applications. The uniformity, efficiency, efficacy, ease of control and ease of scale-up of various physical treatments were compared to support the development of a new phytochemical-enhancing treatment for potential commercial application. These treatment methods were considered independently of the physical characteristics of the produce treated (type of produce, size, shape, and positioning) to reduce the number of parameters to be studied with a view to scale-up processes, following identification of the optimal processing conditions through laboratory-scale testing.