MEASUREMENT OF TOMATO FIRMNESS WITH A UNIVERSAL TESTING MACHINE.

Area of Science:

• Agricultural Science
• Food Science
• Materials Science

Background:

• Tomato firmness is a crucial quality attribute affecting consumer acceptance and post-harvest handling.
• Existing methods for assessing tomato firmness may lack precision in differentiating between anatomical parts.

Purpose of the Study:

• To develop and validate a novel punch-testing technique for quantifying the firmness of distinct anatomical regions within tomatoes.
• To establish a reliable method for evaluating tomato firmness during ripening and across different cultivars.

Main Methods:

• Utilized an Instron Universal Testing Machine equipped with a specialized plunger (0.040-inch tip, 0.020-inch shaft).
• Applied a consistent penetration speed of 1 cm/min to measure force-displacement responses.
• Analyzed force-displacement traces to identify distinct peaks correlating with tissue firmness.

Main Results:

• The punch-testing method generated distinct force-displacement peaks, enabling differentiation of firmness in various tomato structures.
• Successfully monitored changes in firmness throughout the ripening process.
• Demonstrated the ability to detect differences in firmness between tomato varieties and variations across the surface of individual fruits.

Conclusions:

• The developed punch-testing technique provides a precise and versatile tool for assessing tomato firmness.
• This method is valuable for objective quality assessment, research on fruit development, and breeding programs.