Investigating the Impact of the Degree of Sharpness on the Microstructure of Fresh-Cut Apples

Mechanical damage significantly affects the quality and shelf-life of fresh-cut produce. Understanding and controlling the effects of mechanical damage is essential for developing nutritionally rich and sensorially acceptable products. This study investigated how the efficacy of cutting tools may cause mechanical damage to the tissues of Golden Delicious apples, affecting their main physical, chemical, and microstructural properties. The apples were sliced using one kitchen knife with four Degrees of Sharpness (DoS), from sharp (DoS1) to blunt (DoS4). Over 15 days of storage, the apples cut with a DoS1 maintained a higher L* value of 80.1, with minimal changes in the a* value. The apples cut with a blunt knife (DoS4) showed a significant decrease in L* to 78.1 and an increase in the a* value from 1.2 to 3.3. X-ray micro-CT imaging revealed that the porosity at the surface of the apples cut with a DoS1 was 15%, compared to 19% for those cut with a DoS4. Additionally, the DoS4 samples showed greater structural separation at the cut surface, suggesting a larger solid fraction and lower overall quality. This study concludes that the use of blunt tools can cause damage that negatively impacts the overall post-cut quality as a result of the changes induced in the internal microstructure.