CONTINUOUS RADIOFREQUENCY PASTEURIZATION IN SAUSAGE MANUFACTURING LINES

Dielectric heating was chosen as the most promising technique for the development of a continuous and flexible pasteurization process for mo ving sausage emulsions. To increase the penetration depth with respect to products having larger diameters radio-frequency (27 MHz) heating was then selected. Stationary heating experiments at 27 MHz and tests in a specially designed R.F heating line with moving, coagulation type sausage emulsions of various compositions were performed. An approxim ately linear relationship was observed for the temperature increase as a function of electrode voltage. Overall power efficiency was around 30 % and can probably be improved. The maximum temperature difference over the cross-section of the hot (moving) emulsion between experiment s (target temperature about 80-degrees-C) ranged from 6 to 16 K. Produ cts heated in the continuous line were sufficiently coagulated, adequa tely pasteurized, showed good skin formation and had a good overall ap pearance. Sensory evaluations and rheological measurement performed on products, heated parallel in the R.F. line and conventionally to comp arable Cook Values, only revealed minor differences.