The waste water from food processing contains dissolved salts and organic matter. The amount of each depends upon the product being processed and the procedure being used. The suitability for irrigation of food processing waste water from 20 plants processing nine food products was assessed from the standpoint of electrical conductivity (EC), chloride and sodium concentrations, sodium-adsorption-ratio (SAR), and chemical oxygen demand (COD). Waste water from plants processing green beans (Phaseolus vulgaris L.), squash (Cucurbita pepo var. melopepo Alef.), tomatoes (Lycopersicon esculentum Mill.), corn (Zea mays L.), steam peeled potatoes (Solanum tuberosum L.) and sweet potatoes (Ipomoea batatas Lam.), and poultry is suitable for irrigation under most conditions. Waste water from some pea (Pisum sativum L.) and lima beans (Phaseolus lunatus L.) processing plants may be suitable for irrigation, but is of questionable suitability from others. Waste water from lye-peel potato processing is not suitable for irrigation.

This work aims at simulating a retort sterilization process of flexible packaging, performed in autoclave. ANSYS CFD© software has been used in this study to simulate the heat transfer inside the retort chamber. Flexible packaging filled with a pumpkin soup has been modelled. Three-dimensional (3D) geometrical configuration of the equipment has been designed and then simulated to evaluate the sterilization level achieved by each packaging inside the retort chamber. In particular, the internal temperature of the product situated in the cold spot of the chamber has been monitored during 5 min of the process (after reaching 85°C inside the product) in order to monitor the time/temperature trend. Experimental tests have been finally performed to validate the simulation model of heat exchange. The sterilization process takes place in a retort chamber by means of “overheated water sprayed” at 403 K and a pressure of 5 atm. Results show a good agreement between the simulated results and the real retort process and confirm the potential value of the simulation model to evaluate the process performance.

This study uses Taiwan's WEF nexus as a case study to demonstrate how the resource flow and associated environmental impact of the WEF nexus can be assessed as basis for evaluating strategies for promoting the sustainable use of natural resources. In this study, material flow analysis (MFA) and life-cycle assessment (LCA), were combined. The MFA was used to examine the interdependence of the three natural resources, and the LCA was used to evaluate the environmental impacts of the WEF system. The WEF nexus analysis shows that tap water supply, oil refining, the cogeneration of steam and electricity, thermoelectric power plants, irrigation, animal husbandry, and aquaculture are the main interwoven nodes and have the most prominent impact on the three natural resources. When the unit products from the WEF system were determined, LCA was implemented for these products to identify 15 types of environmental impacts. The environmental impacts for the WEF system were then calculated based on the use of unit products. The results of LCA showed that the most prominent impacts are the impact of public electricity on climate change; oil products on ozone depletion and ionizing radiation; tap water on metal depletion; and animal husbandry on terrestrial ecotoxicity. Based on the assessment of the alternative resource management strategies, if both water and energy policies are modified simultaneously, the impact of the overall WEF system on most environmental impact categories could be reduced.

Adsorption isotherms of 3 selected paper-based packaging materials, that is, vegetable parchment (VP) paper, Kraft paper, and solid-bleached-sulfate (SBS) paperboard, were determined at 3 different temperatures (25, 40, and 50 °C). The GAB isotherm model was found to fit adequately for describing experimental adsorption isotherm data for the paper samples. The monolayer moisture content of the paper samples decreased with increase in temperature, which is in the range of 0.0345 to 0.0246, 0.0301 to 0.0238, and 0.0318 to 0.0243 g water/g solid for the MG paper, the Kraft paper, and the SBS paperboard, respectively. The net isosteric heats of sorption (qst) for the paper samples decreased exponentially with increase in moisture content after reaching the maximum values of 18.51, 27.39, and 26.80 kJ/mol for the VP paper, the Kraft paper, and the SBS paperboard, respectively, at low-moisture content. The differential enthalpy and entropy of 3 paper samples showed compensation phenomenon with the isokinetic temperature of 399.7 K indicating that water vapor had been adsorbed onto the paper samples with the same mechanism. Depending on the paper material, tensile strength of paper samples was affected by moisture content.

Steam injection heating systems for food and agricultural products are subject to condensation-induced water hammer (CWH), which may cause significant damage to equipment and pose a threat to operators. A method is suggested for process design and operation of a steam injection heater that reduces occurrence of CWH. The method is based on a correlation between the thermodynamic ratio of the product and the Peclet number. A laboratory steam injection heater was instrumented to determine the relationship between CWH, the thermodynamic ratio, and the Peclet number. The thermodynamic ratio for water and various concentrations (55 to 67.5 brix) of sucrose solution was recorded under process conditions at the onset of CWH during steam injection heating. Good correlation was observed between the Peclet number and threshold thermodynamic ratio. A linear equation was found (with r 2 = 0.79) that gives the predicted minimum thermodynamic ratio for system operation without CWH.