Issue link: https://read.dmtmag.com/i/350705
www.goodfruit.com Good Fruit Grower AUGUST 2014 19 In recent years, Scotian Gold has been using the DA-meter in place of starch- iodine tests to monitor maturity of Honeycrisp and SweeTango apples. Honey- crisp is the number-one variety in Nova Scotia, and har- vesting at the right time is critical, he said, because fruit picked too early tends to develop high levels of bitter pit in storage, while fruit picked too late develops soggy breakdown and internal browning. "You have to know when to pick the fruit," he said. "It has to be picked at the right time to get it out of storage and on the shelf in decent shape. Honeycrisp has to be picked when it wants to be picked and not when you get around to doing it." Traditionally, Honeycrisp apples are picked when they have 75 to 80 percent bright red color and the background is turning from green to straw color. However, because of the warm summer days and cool nights in Nova Scotia, it's not uncommon to have apples with 80 to 85 percent good red color that are still immature inside. Some Honey crisp apples mature without gaining enough color. How it works Dr. Stefano Musacchi, pomologist at Washington State University, said the DA-meter shines beams of light on the apple and the reading is based on the amount of light reemitted by the fruit. The device actually measures the chlorophyll in the mesocarp of the fruit, about three millimeters below the skin. The readings, which decline in value as the fruit ripens and the chlorophyll degrades, are thought to be correlated with ethylene production. Dr. John Delong, postharvest physiologist with Agri- culture and Agri-Food Canada at Kentville, Nova Sco- tia, who introduced the company to the DA- meter, has worked for three years to identify the appropriate read- ings for growers to use. The recommendation now is that growers start picking fruit for long-term storage at a DA-meter index of 0.60. When the index reaches 0.35, fruit should be picked for short-term storage only. Lutz said these numbers are specific to Nova Scotia and are not recommended for other areas. Musacchi said the DA-meter can also be used at the packing house to classify fruit by maturity so it can be stored appropriately. It can also be used by retailers to determine which fruit needs to be sold first. The DA-meter was developed initially as a research tool to assess peach maturity by Dr. Guglielmo Costa at the University of Bologna. It works well for pears as well as apples. It has two gigabytes of memory and a USB port enabling the data to be downloaded to a computer. Manufactured by Sintélleia, it is available from the Italian company T.R. Turoni. For information, check the website at www.trturoni.com/en/. Lutz and Musacchi spoke during the annual meeting of the International Fruit Tree Association in Kelowna, British Columbia, in February. • * Securities products and services such as investment banking and capital raising are offered by KeyBanc Capital Markets Inc., Member NYSE/FINRA/SPIC. Banking products are offered by KeyBank National Association. All credit products are subject to credit approval. Key.com is a registered service mark of KeyCorp. ©2014 KeyCorp. KeyBank is Member FDIC. KeyBank is an Equal Housing lender. ADL7024 We're with you from the ground up For more than a century, KeyBank has delivered a unique combination of agribusiness knowledge, experience, and flexible service. We have solutions to help our clients, whether you're a grower, processor, packager, or distributor. Our tailored solutions spring from our understanding of the cycles of farming, seasonal dynamics, and the unique risks associated with the industry.. KeyBank is one of the nation's leading agribusiness lenders. We specialize in: • Financing for the future • Managing short- and long-term cash • Planning, protecting, and safeguarding your assets • Access to capital markets expertise and capabilities* These services can help protect you from the inevitable up-and-down cycles that agribusinesses face. Contact us today. We want to help your business grow and thrive. To learn more, call Mike McKay at 800-346-8828 or visit key.com/agribusiness. COURTESY OF GUGLIELMO COSTA. The DA-meter was invented to replace the "dreaded starch iodine test" to assess fruit maturity.