PROCESSING AND PHYSICOCHEMICAL PARAMETERS OF WHEY-BASED POPSICLES SUBMITTED TO OHMIC HEATING

Emerging technologies have the potential to decrease processing time while aiding in the preservation of the physicochemical properties of dairy products. This study aimed to assess the impact of ohmic heating (OH) on processing parameters and physicochemical characteristics of watermelon and whey-based popsicles. Popsicles were processed using OH under different electric fields: 30V (3.33V/cm; T1), 60V (6.67V/cm; T2), and 90V (10.00V/cm), and by pasteurization (70°C/30 minutes; TP). An untreated sample (TC) was used as a control. After processing, the following were calculated: energy consumption, heating rate, electrical conductivity, heat generation, and volumetric heat generation. Additionally, physicochemical analyses were performed, including pH, total acidity, color, melting rate, and volatile organic compounds. Energy consumption was higher for the conventional treatment (773.972KJ; p<0.05), and the lowest heating rate (1.9°C/min) was observed at the lowest electric field strength, which did not differ from the conventional treatment (p>0.05). Electrical conductivity differed (p<0.05) among the applied electric fields, with the highest (1.719S/m) observed at the lowest intensity. Heat generation (1.909–17.012mW) and volumetric heat generation (0.573–5.104µW/m3) increased with increasing intensity (p<0.05). There was no significant difference (p>0.05) in the pH of the samples, and the lowest acidity (0.09mg lactic acid/100g) was observed at the highest intensity (p<0.05). The lowest applied intensity resulted in the slowest melting rate (0.56 g/min), which did not differ from the conventional treatment (0.573g/min; p<0.05). Color parameters did not differ (p>0.05) between OH-treated samples and pasteurization. Forty-six (46) volatile organic compounds were identified in samples treated with medium and high intensities and untreated samples, 36 treated with low intensity, and 49 in pasteurized samples. Therefore, OH has shown greater energy efficiency in processing and can be an alternative to the treatment of popsicles compared to pasteurization, especially at medium and high intensities.