Abstract
Osmotic dehydration of chestnut slices in sucrose was optimized for the first time by Response Surface Methodology (RSM). Experiments were planned according to a three-factor central composite design (α=1.68), studying the influence of sucrose concentration, temperature and time, on the following parameters: volume ratio, water activity, color variation, weight reduction, solids gain, water loss and normalized moisture content, as well as total moisture, ash and fat contents. The experimental data was adequately fitted into second-order polynomial models with coefficients of determination (R 2 ) from 0.716 to 0.976, adjusted-R 2 values from 0.460 to 0.954, and non-significant lacks of fit. The optimal osmotic dehydration process conditions for maximum water loss and minimum solids gain and color variation were determined by the “Response Optimizer” option: 83% sucrose concentration, 20 °C and 9.2 hours. Thus, the best operational conditions corresponded to high sugar concentration and low temperature, improving energy saving and decreasing the process costs.
Highlights
Chestnut production is of great economic importance for some countries
Portugal accounts for about 15% of the European production (Food and Agriculture Organization of the United Nations, 2014), with the North area, mainly Trasos-Montes region, contributing to 80.5% of the national production and representing 87.4% of chestnut national production area (30586 ha) (Instituto Nacional de Estatıstica, 2014)
Values of color variation predicted by the mathematical model were similar to the experimental data (Table 2), yielding a good fit with a R2 of 0.976 and an adj-R2 of 0.954 (Table 3), meaning that the experimental data may be predicted with great accuracy
Summary
Chestnut production is of great economic importance for some countries. In 2012, the main world producer was China, representing about 82.5% of the total production, followed by Europe, with 6.4% (Food and Agriculture Organization of the United Nations, 2014). Portugal accounts for about 15% of the European production (Food and Agriculture Organization of the United Nations, 2014), with the North area, mainly Trasos-Montes region, contributing to 80.5% of the national production and representing 87.4% of chestnut national production area (30586 ha) (Instituto Nacional de Estatıstica, 2014). Some problems may arise during chestnuts’ storage, compromising its availability and quality throughout the year. One way to mitigate this problem is to use different post-harvest technologies such as low temperature storage or convection drying.
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
