Nondestructive detection of hollow heart in potatoes using ultrasonics

Abstract

Potato is required for food processing, with very good quality, suitable external and internal appearance. Standardization standards include standards for potato grading and certification, used for classification into quality classes. No more than 5% of potato tubers may have internal defects, such as: rusty flecks, "cork", "hollow hearts", also called "hollow" and heterogeneity and discoloration of the flesh. "Serious damage" means a defect that can not be removed without losing more than 10% of the total weight. If these quantities are exceeded, the farmer receives a significantly lower price for the raw material. The aim of this work was to develop a non-destructive method for the detection of 'empty hearts' in potato tubers using ultrasound. The specific objectives are: indication of the possibility of using ultrasound in the frequency range: 50 kHz, 250 kHz, 500 kHz and 1 MHz for detecting 'empty hearts' in potatoes and measuring the physical characteristics of potato, which affect the acoustic characteristics, then determining them and choosing them that may be useful and used to separate the 'heart' from the hollow potato tubers. Non-destructive ultrasound techniques were used to detect the hollow "empty hearts" of a potato. Tubers of 4 potato cultivars were assessed physically and acoustically at different frequencies from 50 kHz to 1 MHz. Ultrasound transducers were used to create an ultrasonic impulse, at a power of up to 0.22 W. The test of acoustic transmission through whole potato tubers in the transverse direction at various positions: along the longitudinal axis over a certain distance interval. [...]