Thermophysical Properties of Lemon Juice as Affected by Temperature and Water Content

To design equipment for food processing and estimate process times for refrigerating, freezing, heating, or drying of foods, the thermophysical properties must be known, Since the thermophysical properties of foods are strongly dependent upon chemical composition and temperature, composition and temperature based models provide a means of estimating these properties. In this work, the thermophysical properties of lemon juice were determined at a water mass fraction of (0.381 to 0.900) and a temperature of (273.45 to 353.75) K. Density and thermal conductivity varied from (962.3 to 1282.8) kg.m(-3) and (0.344 to 0.624) W.m(-2).K(-1), respectively. Heat capacity and thermal diffusivity varied from (2446.5 to 4060.1) J.kg(-1).K(-1) and (0.1160.10(-6) to 0.1785.10(-6)) m(2).s(-1), respectively. Simple polynomial functions were fitted to the experimental data, and good agreements were obtained. In the tested range, water content showed greater influence oil the thermophysical properties.Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP

Thermophysical Properties of Industrial Sugar Cane Juices for the Production of Bioethanol

To design equipment for biofuel production and all optimizing process for heating, settling, and filtration of industrial sugar cane juices, the thermophysical properties Must be known. Since the thermophysical properties of biological materials are strongly dependent upon chemical composition and temperature, composition- and temperature-based models provide a means of estimating these properties. In this work, the thermophysical properties of untreated sugar cane juice (USCJ), mixed Sugar cane juice (MSCJ), and clarified sugar cane juice (CSCJ) were determined at a temperature range of (277.4 to 373.4) K. Simple polynomial models as a function of temperature were fitted to the experimental data, showing good agreement. Thermal conductivity and heat capacity varied front (0.475 to 0.493) W.m(-1).K(-1) and (3601.8 to 3802.9) J.kg(-1).K(-1), respectively. Density varied from (1044.5 to 1189.5) kg.m(-3).Fundação de Amparo à Pesquisa do Estado de São Paulo (FAPESP