Dry matter is comprised of a kiwifruit's soluble solids (sugar) and insoluble solids (structural carbohydrates and starch) and is a primary indicator of fruit maturity.
Two separate studies are illustrated in this infographic demonstrating that dry matter is the primary factor affecting kiwifruit quality and flavor and that higher dry matter is the most important trait driving consumer acceptance when compared to both fruit price and size.
Interestingly, of the three traits studied, fruit size is least important to consumers in their purchase decisions.
The infographic How Important is Kiwifruit Dry Matter? is free to download. Please, click on the link at the end of the text.
How to measure dry matter of kiwifruit?
Dry matter estimation helps growers of kiwifruits in many ways; from estimating time of harvest, maintaining the quality of fruits, preventing postharvest diseases, to extending storage time. Especially in cases of kiwifruits meant for international sale, quick and easy dry matter estimation can decrease risks and increase profits for stakeholders at all levels.
Just as in other fruits, there are destructive and non-destructive methods of estimating dry matter content of kiwifruits. The destructive methods (fruit dehydrator or oven drying) are laborious, time consuming, and cannot be carried in the field, as the tests require laboratory conditions. However, the results achieved are precise.
Near Infrared (NIR) spectroscopy is one of the most popular and reliable non-destructive methods. Light reflected in various wavelengths by solid components of the fruit is recorded using spectroscopy to give an estimate of their proportions.
The recently upgraded F-751 Kiwifruit Quality Meter, produced by FELIX INSTRUMENTS - Applied Food Science uses NIR spectroscopy to estimate dry matter. The F-751 is simple, lightweight, and user-friendly.
- The F-751 can display results in as little as 12 seconds.
- It has an integrated GPS for repeat readings and tree mapping.
- The device has integrated software for storage and data transfer to computers.
Besides measuring dry matter, the F-751 can also estimate soluble solids (SSC), titratable acidity, and color of fruits. Since optimum dry matter values for harvest are connected with titratable acidity, this device is ideal for kiwifruit growers.