ELSEVIER Joumal of Food Engineeing 36 (1998) 201-210 @ 1998Elsevier ScienceLimited. All rights reserved Printed in Great Britain PII: S026o-E774(9E)00040-5 0260-8774198$19.00+0.00 Bxperimental Study of Hydro-aerosolCooling of Sausages: Effect of the Process Factorson the Cooling Intensity Valentina Grozdanova Georgieva and StepanGaro Akterian* Department of Food Process Engineering, Higher Institute of Food Industry, 26 Maritza Boulevard, Plovdiv 4002, Bulgaria (Received15 November 1996; accepted 17 February 1998) ABSTRACT The objective of the papo was the controllable hydro-aerosol cooling process of scaldedand smoked sausages and the ffict of the main process factors on the cooling intensiSt to be studied. The hydro-aerosol medium includes water droplets dispersedin moist air The total cooling time, cooling rate and surface heat-transfer coefficient were used as indexes for estimating the heat-transfer intensity. The order of the studied process factors ranked by their significance is the following: sausage diameter (1'62), cooling water temperature(0'14), air- flow velocity (-0'10) and air-flow temperafiire(0'10). Sensitivity functions are pointed betweenbiskets and they show the change of an intensity index caused by a unit vaiation of a process factor The intensityof the studied controllable hydro-aerosolcooling is 1'4-3'8 times higher than the cooling at industial conditions. The hydro-aerosol cooling can ensure the production of safety, high quality sausages with natural and synthetic covers and their shelf-lifu to be prolonged. A 1998 Elsevier Science Limited. Ail nghts reserved Bi = h*(dl2)lk c,k, P d F. F', V" NOMENCIATURE The modified number of Biot Specific. heat capacity (J kg-t5-t), thermal conductivity (W m ' K-') and density (kg m-') of sausage Sausage diameter (mm) Crosslsection area of the experimental chamber (m2) Heat-transfer surface (m2f and volume (m3) of the sausage studied *To whom all correspondence should be addressed. Fax +359-32-440102; e-mail akte- rian@hifli-plovdiv.acad.bg or akterican@plor.omega.bg 201