Influence of °Brix/Acid, and flow rate of pineapple juice and electric field strength on the performance of continuous ohmic heating system.

Unlabelled: A lab-scale continuous ohmic heating (COH) system was developed, and its performance was studied for pineapple juice heating as a model sample. The effect of independent parameters [°Brix/Acid (unstandardized, 18, 22, 26) and flow rate (80-120 mL/min) of juice and electric field strength (EFS: 25-45 V/cm)] were analysed for responses viz. come-up-time, heating rate (HR) and system performance coefficient (SPC). The full factorial experimental design was used for this study. The results showed that with an increase in °Brix/Acid, the % acidity and electrical conductivity decreased significantly ( < 0.05); thus, the come-up-time to reach 90 °C increased significantly. The HR was significantly ( < 0.05) influenced by °Brix/Acid and EFS but less so by flow rates at higher EFS. The SPC was more than 0.90 and reduced significantly ( < 0.05) with an increase in °Brix/Acid and flow rate. The HR was modeled using a feed-forward back-propagation artificial neural network (ANN) with the best topology of 3, 5, and 1 neurons in the input (independent), hidden, and output (response) layers, respectively. The model performed efficiently, which is evident from the high R (0.998) and low RMSE (1.255). Thus, the COH, with its high efficiency and HR, can effectively be used to process fruit juice.

Supplementary Information: The online version contains supplementary material available at 10.1007/s13197-024-05961-x.