OPTIMIZATION OF ULTRASOUND-ASSISTED BRINING FOR MEAT PRESERVATION USING A COMPOSITE PERFORMANCE INDEX

Abstract

This study evaluates the impact of ultrasound-assisted brining (37 kHz) on pork meat (Longissimus dorsi), analyzing the effects of brine concentration (15% – C1 and 25% – C2) and exposure time (30 and 60 min) compared to conventional immersion brining (T0). The results demonstrate that ultrasound significantly accelerates salt diffusion through acoustic cavitation, reaching a maximum NaCl content of 18.35% and reducing water activity to 0.942 under the C2T60 treatment. This dynamic is accompanied by a progressive decrease in pH and biphasic changes in free ammonia content. Optically, moderate exposure (30 min) enhances redness intensity (a*), whereas prolonged treatment (60 min) intensifies pigment oxidation, increasing the metmyoglobin (MMb) fraction and promoting undesirable yellow-brown hues. Principal Component Analysis (PCA) confirmed that treatment duration is the dominant factor driving system variability. For an integrated evaluation, a Composite Performance Index (CPI) was developed to synthesize the physicochemical, oxidative, and color parameters into a single score.