Good Fruit Grower

April 1

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Page 44 of 55 GOOD FRUIT GROWER APRIL 1, 2015 45 fruit had some flesh browning, particularly around the stone. This damage may be due to the relatively high internal temperatures in small fruit. In small fruit, weighing 170 to 180 grams (about 6 ounces), the internal temperature varied from 55°C to 63°C (131°F to 154°F), compared with a temperature range of 41°C to 45°C (106°F to 113°F) in large fruit. The scientists estimated the cost of the electricity needed for such a treatment, based on the prototype microwave equipment they used. With the price of elec- tricity at 0.18 Euros a kilowatt-hour in Spain, the cost ranged between 0.02 and 0.03 Euros per kilogram (1 to 1.5 cents per pound), depending on the treatment. The cost of the equipment would be additional. Water In a second study, the researchers explored ways to ensure a more uniform temperature distribution in the fruit in order to avoid the internal browning problem in small fruit. The differing dielectric (electric insulating) properties of the fruit and the surrounding air are believed to result in uneven distribution of the microwaves. To overcome that, the scientists immersed the peaches in water during the microwave treatment. For their experiments, fruit at room temperature were placed in a container and submerged in water at a temperature of 20°C, 35°C, 40°C, or 45°C. The containers were placed on the conveyor belt and the microwave treatment applied. The internal temperature of the fruit was monitored with a probe during the treatment and the external temperature was recorded immediately afterwards. Fruit were cut in half after being held for five days at room temperature to check for internal browning. Microwave treatment at 10 kW for 95 seconds with fruit immersed in water at 20°C did not control brown rot, and hotter water gave only slightly better results. Immersing the fruit in water solved the problem of inter- nal damage, but reduced the efficacy of the treatment, probably because fruit temperatures never got above 42°C in any of the treatments. When the power level was increased to 20 kW for 50 to 60 seconds, brown rot was controlled without any fruit damage. The researchers saw a similar effect with nectarines. Funds from the University of Leida and the Spanish Ministry of Economy and Competitiveness financed the research, which involved three years of testing. The next phase of the project is to build a prototype microwave device so that fruit processors can add it to their production line. Articles on this research were published in the sci- entific journals Postharvest Biology and Technology and Innovative Food Science and Emerging Technologies. • An industrial microwave with a continuous conveyor belt was used for the experiments. "We knew that this microorganism is sensitive to temperature." —Josep Usall Get the Chinook FAN BLADE ADVANTAGE! TRITON V-10 TRITON 5.4 PROPANE FUEL INJECTION IVECO NEF 6.7 DIESEL 2921 Sutherland Park Drive Yakima, WA 98903-1891 ENGINEERING RELIABILITY & PERFORMANCE I've been doing business with H.F. Hauff Company since 1978. They engineer their products with a farmer's needs in mind and have tre- mendous integrity. I like the fact that they stay in touch with their growers. • Victair Sprayers are reliable and built to use for a long time. Application windows can be short and you just can't afford to have down time. Any necessary repairs are simple to make. • Wind machines are my insurance plan. In today's world, you cannot afford to lose a crop. If you save just a quarter of a crop, you have paid for the machines. • No under-prop dead-air zone The way other props are designed, they don't push air down around the tower like the Chinook blade. • The Chinook puts out 30% more air, so you can stretch the towers out farther or get more air movement • 30% savings in fuel, it's huge! Chinook wind machines use less fuel because the machines are more efficient. BILL HENRI NAMPA, CALIFORNIA 509-248-0318 fax 509-248-0914 TOLL FREE 855-855-0318 Consider for your next planting: • BRUCE PONDER • SUSAN WILKINSON • ADAM WEIL • DAVE WEIL 503-538-2131 • FAX: 503-538-7616 BENEFITS: • Disease tolerant • Cold hardy • Adapts well to all cherry-growing districts • Forms flower buds and comes into bearing quicker than Mazzard with a better distribution of flower buds Now booking orders for 2016 Call Tree Connection: 800-421-4001 Dwarfing Cherry Rootstock Krymsk ® 5 Krymsk ® 6 [cv. VSL-2, USPP 15,723] [cv. LC-52, USPP 16,114] "Krymsk ® 5 and Krymsk ® 6 cherry rootstocks have proven to be the best rootstock for our orchards. They are yield efficient, grow and adapt well, and are cold hardy." —John Morton The Dalles, Oregon

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