Jansrimanee Supawadee, Lertworasirikul Saowanee
Department of Product Development, Faculty of Agro-Industry, Kasetsart University, 50 Ngamwongwan Rd., Chatuchak, Bangkok 10900, Thailand.
Department of Product Development, Faculty of Agro-Industry, Kasetsart University, 50 Ngamwongwan Rd., Chatuchak, Bangkok 10900, Thailand.
Ultrason Sonochem. 2020 Dec;69:105256. doi: 10.1016/j.ultsonch.2020.105256. Epub 2020 Jul 15.
This research studied the effects of combined ultrasound and 3% sodium alginate (SA) coating pretreatment (US + Coat) on mass transfer kinetics, quality aspects, and cell structure of osmotic dehydrated (OD) pumpkin. The results of the pretreatment were compared with the results of control (non-pretreated osmotic dehydration) and other three pretreatment methods, which were 1) ultrasound in distilled water for 10 min (USC), 2) ultrasound in 70% (w/w) sucrose solution (US) for 10, 20 and 30 min, and 3) coating with 1%, 2%, 3% (w/w) SA. The coating pretreatments with SA resulted in a higher water loss (WL) but lower water activity and solid gain (SG) than other treatments. US pretreatments resulted in the highest effective diffusion coefficients of water (D) and solid (D) but the cell structure of the product was deformed. The 3% SA coating treatment had the highest WL/SG (5.28) but with the longest OD time (12 h). Using the US + Coat pretreatment gave satisfactory high WL/SG (5.18), D (1.09 × 10 ms) and D (5.15 × 10 ms), reduced the OD time to 9 h, and preserved the cell structure of the product. This research suggests that US + Coat pretreatment can be an effective processing step in the production of OD pumpkin.
本研究探讨了超声与3%海藻酸钠（SA）涂膜预处理（US + Coat）对渗透脱水（OD）南瓜传质动力学、品质特性及细胞结构的影响。将该预处理结果与对照（未预处理的渗透脱水）及其他三种预处理方法的结果进行比较，其他三种预处理方法分别为：1）在蒸馏水中超声处理10分钟（USC）；2）在70%（w/w）蔗糖溶液（US）中超声处理10、20和30分钟；3）用1%、2%、3%（w/w）的SA进行涂膜处理。与其他处理相比，SA涂膜预处理导致更高的失水量（WL），但水分活度和固形物增量（SG）更低。超声预处理导致水（D）和固形物（D）的有效扩散系数最高，但产品的细胞结构发生变形。3% SA涂膜处理的WL/SG最高（5.28），但OD时间最长（12小时）。采用US + Coat预处理可获得令人满意的高WL/SG（5.18）、D（1.09×10 米²/秒）和D（5.15×10 米²/秒），将OD时间缩短至9小时，并保留了产品的细胞结构。本研究表明，US + Coat预处理可成为OD南瓜生产中的有效加工步骤。
