Ultrasonic technology for quality evaluation of fresh fruit and vegetables in pre- and postharvest processes

Increasing public demands for improved quality of fruit and vegetables in the fresh market and the food industry, and growers’ expectations of high prices for premium quality products, raise the necessity for fast, accurate, and objective methods for measuring and monitoring product quality along the chain of pre- and postharvest processes, from the field to the consumer. Ultrasound technology provides one of the foundations for a non-destructive, fast and reliable technique for correlating specific quality-related indices and characteristics of fruit and vegetables with the stages of development during growth and maturation, and in the course of storage and shelf-life, until they are ready for consumption. This review summarizes the last two decades of studies, adaptation, modification, and innovation of ultrasound technology and devices for determination of material properties of fresh fruit and vegetable tissues, in both pre- and postharvest applications. Included are descriptions of the various methods of ultrasonic measurement, the equipment, the procedures for data processing and correlating the measurements of ultrasound parameters with quality indices of fruit and vegetables in the course of the various pre- and postharvest processes. It is concluded that much progress has been made in these fields during recent years.