Solar drying of strawberry using polycarbonate with UV protection and polyethylene covers: Influence on anthocyanin and total phenolic content
Autor: | Sahylin Muñiz-Becerá, Juan Rodríguez-Ramírez, Lilia Leticia Méndez-Lagunas, Anabel López-Ortiz, Karunakaran Nair |
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Rok vydání: | 2021 |
Předmět: |
Solar dryer
Uv protection Materials science Renewable Energy Sustainability and the Environment 020209 energy Greenhouse 02 engineering and technology Polyethylene Solar drying 021001 nanoscience & nanotechnology chemistry.chemical_compound chemistry Chemical engineering Anthocyanin visual_art 0202 electrical engineering electronic engineering information engineering visual_art.visual_art_medium General Materials Science Polycarbonate 0210 nano-technology Water content |
Zdroj: | Solar Energy. 221:120-130 |
ISSN: | 0038-092X |
Popis: | Cover material of solar dryers influences on fruit properties due to the temperature and ultraviolet radiation (UV) during drying. Polyethylene (P) is the most used material for covering solar dryers. Cellular polycarbonate (CP) is a material that promotes UV protection; hence, it has recently been proposed as a covering material for greenhouse dryers. However, it is unknown whether CP cover will have any effect on bioactive compounds of foods treated by solar drying. Especially, if CP has advantages in preserving sensitive compounds compared to traditional materials as P. In this work the effect of CP and P covers on anthocyanins (TA) and total phenolic compounds (TPC) of strawberries during solar drying was evaluated. Open sun drying was used as a reference. Drying temperature, solar radiation, external and internal UV radiation was measured. The results indicated that the drying temperature and UV radiation influenced the moisture content and bioactive compounds. Direct radiation increased the drying temperature and reduced the final moisture content, while the partial incidence of UV radiation in the dried samples with P covers favored the remaining 40.7% of TA and 42.5% of TPC. With CP covers, where the ultraviolet radiation was zero, the 15.5% of TA and 14.4% of TPC were retained. Activation energy indicated that bioactives were more stable in the solar dryer with P and transparent cellular polycarbonate covers, demonstrated that they can be used as coatings in solar dryers destined for drying fruits, producing high-quality dehydrated products and efficient solar drying processes. |
Databáze: | OpenAIRE |
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