Drying of foods is a preservation method that aims to prolong the product shelf life and simplify its transport and storage. However, this process requires a large amount of energy, which results in high emissions of contaminants in the environment. In this work, Life Cycle Assessment (LCA) analysis was applied to the drying of strawberries. In particular, for the first time, traditional freeze drying and the combination of osmotic dehydration + freeze drying were analysed and compared to verify if the application of the pre-treatment was effective in reducing the environmental impact, obtaining a more sustainable process. The chosen functional unit was one 450 g dried strawberriesâ package. Strawberries were gathered in 2016, from May to September. Primary data related to the drying process were used to perform mass and energy balances and compile the life cycle inventory. The LCA analysis was accomplished using SimaPro 8.0.5 software, in accordance with ISO 14040â14044. The calculations on the traditional freeze drying process were made considering actual operation factory data, whereas the calculations on the osmotic + freeze drying process were desk calculations. The comparison of freeze drying and osmotic dehydration + freeze drying on industrial scale revealed that the traditional process generated higher emissions in terms of all the studied environmental categories. A scenario analysis was, then, carried out to evaluate the potential emissionsâ reduction due to the variation of some process times. An improved scenario based on the use of osmotic dehydration + freeze drying with optimised process times was, therefore, proposed; using the improved process, a reduction of the emissions equal to 25% with respect to the traditional freeze drying process could be obtained. Sensitivity analysis showed that variations in fertilisersâ amount and in condenser and vacuum pump power did not cause significant changes to the results. The results also showed moderate sensitivity to strawberriesâ transport distance.
Optimization of freeze-drying using a Life Cycle Assessment approach: Strawberries' case study
DE MARCO, Iolanda
2017-01-01
Abstract
Drying of foods is a preservation method that aims to prolong the product shelf life and simplify its transport and storage. However, this process requires a large amount of energy, which results in high emissions of contaminants in the environment. In this work, Life Cycle Assessment (LCA) analysis was applied to the drying of strawberries. In particular, for the first time, traditional freeze drying and the combination of osmotic dehydration + freeze drying were analysed and compared to verify if the application of the pre-treatment was effective in reducing the environmental impact, obtaining a more sustainable process. The chosen functional unit was one 450 g dried strawberriesâ package. Strawberries were gathered in 2016, from May to September. Primary data related to the drying process were used to perform mass and energy balances and compile the life cycle inventory. The LCA analysis was accomplished using SimaPro 8.0.5 software, in accordance with ISO 14040â14044. The calculations on the traditional freeze drying process were made considering actual operation factory data, whereas the calculations on the osmotic + freeze drying process were desk calculations. The comparison of freeze drying and osmotic dehydration + freeze drying on industrial scale revealed that the traditional process generated higher emissions in terms of all the studied environmental categories. A scenario analysis was, then, carried out to evaluate the potential emissionsâ reduction due to the variation of some process times. An improved scenario based on the use of osmotic dehydration + freeze drying with optimised process times was, therefore, proposed; using the improved process, a reduction of the emissions equal to 25% with respect to the traditional freeze drying process could be obtained. Sensitivity analysis showed that variations in fertilisersâ amount and in condenser and vacuum pump power did not cause significant changes to the results. The results also showed moderate sensitivity to strawberriesâ transport distance.I documenti in IRIS sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.
