Physical and biochemical changes in ultra-rapid air chilled broiler muscle and quality of marinated chicken breast filets

Abstract

The effect of ultra-rapid chilling in air at −20 °C over water-immersion chilling on broiler carcasses was investigated for physical and biochemical attributes. Forty-eight eviscerated carcasses were divided into two groups, one group were subjected to air chilling and other to water-immersion chilling, and samples were drawn at time periods of 1, 3 and 24 h post-chill to analyze for pH, ratios of adenine: inosine nucleotide (R-values), expressible moisture, cook yield, tenderness and color. Ultra-rapid air chilled carcasses showed significant differences (P < 0.05) in pH, expressible moisture and cook yield at chosen post-chill time intervals over the carcasses chilled using water-immersion technique. It was concluded that air chilled carcasses had higher pH and expressible moisture, but the R-values, and shear values did not show significant differences, and only slight difference in color of carcasses processed by the two chilling methods. In a separate experiment with 108 commercially processed carcasses, quality attributes of pre-rigor marinated breast filets were studied after subjecting the carcasses to air chilling and water-immersion chilling. Twelve filets from air and water chilled carcass aged for 1, 3, and 24 h were tumble marinated for 25 min in a Sodium Tri Polyphosphate (STPP) and NaCl solution with different pick up levels of 10, 15 and 20%. After measuring marinade absorption, filets were aged at 2 °C for 24 h. No differences were observed between the air and water chilling treatments in terms of marinade retention at different marinade target levels (10, 15 and 20%) and time intervals (24, 27 and 47 h) but cook yield of air chilled marinated fillet was higher. In conclusion, processors using further-processing operations that debone meat may find that AC to be more suitable alternative for cooling poultry carcasses because fillet color, marination yield, and tenderness were not affected, but cook yield was improved.