Anais do Congresso Brasileiro de Ciência e Tecnologia de Alimentos

Introduction: Ohmic heating has proven to be an emerging technology with potential for application, offering nutritional and technological advantages. Listeria monocytogenes is a pathogen of importance especially in dairy products, and its kinetic investigation is important for food processing. Objective: Determine the inactivation kinetics of Listeria monocytogenes in whey dairy beverage submitted to ohmic heating and evaluate the physicochemical properties after processing. Methods: Whey dairy beverage was submitted to ohmic heating processing (OH, 3 V/cm, 57.5–60 °C for 38-4 min). Physicochemical characterization (pH, color and hydroxymethylfurfural content) and sensory analysis were performed. Results: OH at 65 °C resulted in a reduction rate (RR) of 2.10 log CFU/mL.min−1 while conventional processing (CP) resulted in RR of 1.38 log CFU/mL.min−1 of Listeria monocytogenes. CP-treated samples presented higher pH values when compared to both the OH-treated samples (6.62–6.91 against 5.99–6.00, respectively, p > 0.05) and unprocessed samples (control). Although higher HMF levels were observed for the samples subjected to both technologies when compared to the control (0.52 μmol g−1, p < 0.05), the OH-treated samples presented lower HMF values than CP-treated samples (2.51–4.61 against 7.54–7.69 μmol g−1, p < 0.05). In general, a slight change in the color parameters was observed, mainly for the OH-treated samples. Higher sensory scores were observed for the OH-treated samples when compared to CP-treated samples for the attributes appearance, aroma, taste, and flavor (6.23–6.92, 8.14–8.31, 8.09–8.56, 7.45–7.98 against 5.23–5.82, 6.37–6.58, 6.26–6.98, 6.02–6.78, for OH and CP, respectively, p < 0.05) suggesting that the OH technology allowed the production of samples with a good sensory performance from the consumers' point of view. Conclusion: Overall, OH is an interesting technology to be used in whey dairy beverage processing. The results of this study comprise key and useful data for application in quantitative risk models to estimate the risk of listeriosis due to the consumption of whey dairy beverages.