Effects of 27.12 MHz Radio Frequency on the Rapid and Uniform Tempering of Cylindrical Frozen Pork Loin (Longissimus thoracis et lumborum)

• Published in: Korean journal for food science of animal resources Vol. 37; no. 4; pp. 518 - 528
• Main Authors: Choi, Eun Ji, Park, Hae Woong, Yang, Hui Seon, Kim, Jin Se, Chun, Ho Hyun
• Format: Journal Article
• Language: Korean
• Published: 2017
• Subjects: tempering; radio frequency; freezing; pork loin; quality
• ISSN: 1225-8563; 2234-246X

Quality characteristics of frozen cylindrical pork loin were evaluated following different tempering methods: 27.12 MHz curved-electrode radio frequency (RF) at 1000 and 1500 W, and forced-air convection (FC) or water immersion (WI) at $4^{\circ}C$ and $20^{\circ}C$. The developed RF tempering system with the newly designed curved-electrode achieved relatively uniform tempering compared to a parallel-plate RF system. FC tempering at $4^{\circ}C$ was the most time-consuming process, whereas 1500 W RF was the shortest. Pork sample drip loss, water holding capacity, color, and microbiological quality declined after WI tempering at $20^{\circ}C$. Conversely, RF tempering yielded minimal sample changes in drip loss, microstructure, color, and total aerobic bacteria counts, along with relatively uniform internal sample temperature distributions compared to those of the other tempering treatments. These results indicate that curved-electrode RF tempering could be used to provide rapid defrosting with minimal quality deterioration of cylindrical frozen meat block products.