Developing cold air assisted radio frequency tempering protocol based on heating rate, uniformity, and quality of frozen chicken breast

Abstract

Radio frequency (RF) heating as an emerging technology has been widely used for tempering and thawing of frozen meat products, while the RF heating non-uniformity is still the main problem before industrial applications. The objective of this study was to provide a new method for improving the RF heating uniformity by adding cold air (−5 °C, 1.5 m/s) around the frozen chicken breast in a rectangular polypropylene container. The effects of cold air assisted RF tempering (CARFT), RF tempering (RFT), air tempering (AT), water tempering (WT), and refrigerator tempering (RT) on heating behaviors and quality of chicken breast were also compared. The results showed that the cold air slightly reduced the RF heating rate but significantly ( P < 0.05) improved the heating uniformity of frozen chicken breast during RFT. Meanwhile, the optimal tempering method was CARFT at the electrode gap of 110 mm, which could provide a larger heating rate than AT, WT and RT and a better heating uniformity than AT, WT and RFT. Additionally, the quality, such as color, drip loss (1.42%), pH (6.38), and total volatile base nitrogen (10.37 mg/100 g), of CARFT treated chicken breast were better than those with other methods. Therefore, CARFT can further be expanded to optimize industrial-scale RF tempering protocols in frozen chicken breast. • RF heating non-uniformity is still the main problem of industrial tempering applications. • Added cold air improved the RF heating uniformity of frozen chicken breast. • Optimal tempering method was cold air assisted RF tempering with electrode gap of 110 mm. • Quality of CARFT treated chicken breast was better than that with other methods.