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i The freezing of food is the most significant application of refrigeration. In order for freezing operations to be cost-effective, it is necessary to optimally design the refrigeration equipment. This requires estimation of the freezing times of foods and the corresponding refrigeration loads. These estimates, in turn, depend upon the surface heat transfer coefficient for the freezing operation. This paper describes the thermodynamics of food freezing and reviews basic freezing time estimation methods. It also describes a study which was initiated to resolve deficiencies in heat transfer coefficient data for food freezing processes. Members of the food refrigeration industry were contacted to collect freezing curves and surface heat transfer data. A unique iterative algorithm was developed to estimate the surface heat transfer coefficients of foods based upon their freezing curves. Making use of this algorithm, heat transfer coefficients for various food items were calculated from the freezing curves collected during the industrial survey