To develop cultivars with improved texture, we need to first understand the nature of blueberry texture and identify means to appropriately measure it. Texture is a complex trait, determined by many factors such as cell wall composition,
![](data:image/svg+xml,%3Csvg%20xmlns='http://www.w3.org/2000/svg'%20viewBox='0%200%20847%201024'%3E%3C/svg%3E)
turgor, and biochemical constitution. Measuring or quantifying texture is a complicated task as well. My research with others at the Plants for Human Health Institute at NC State University is aimed at finding the best way to assess the texture of blueberry fruit. Simple instruments that measure a single mechanical parameter have been widely used in the blueberry industry. However, our findings suggest that one parameter is not enough to understand the complex characteristics of fruit texture. Our research group, in collaboration with international scientists, developed a method that can dissect the blueberry texture using 17 mechanical parameters. The abundance of parameters allowed us to examine the texture of blueberries with much higher resolution.
Further investigation into the rich data obtained from 17 parameters suggested that the mechanical texture of blueberries is mainly determined by four components. Each component contributes in its own way, and different parameters should be used to measure different components. For example, the stiffness or resistance to deformation can be measured using parameters called ‘F1mm’ (force measured at 1 mm depth) or ‘Young’s Modulus’ (function of force vs. strain). Another example is the sensory perception of hardness, springiness, or crispness having high correlation with a parameter called ‘FM’ (maximum force measured at skin break). The take-home message here is that blueberry texture cannot be understood by just one component; it is important to collect data for different components to evaluate different aspects of texture. To accomplish this, multiple parameters need to be assessed and not one.