Effects of combined pretreatments on drying kinetics and quality of potato chips undergoing low-pressure superheated steam drying = ผลของการบำบัดก่อนแบบผสมผสานต่อจลนพลศาสตร์การอบแห้งและคุณภาพของมันฝรั่งแผ่นที่ผ่านการอบแห้งด้วยไอน้ำร้อนยวดยิ่งที่สภาวะความด
- ผู้เขียน
เพชร พิมพาภรณ์
- เอกสารที่มา
วิทยานิพนธ์. (2005) 107 หน้า
หัวข้อ:
บทคัดย่อ
The influences of various pretreatments and drying temperature on the drying kinetics and quality parameters of potato chips were investigated in this study. Low-pressure superheated steam drying (LPSSD) of potato chips underwent various combined pretreatments including blanching, immersion in glycerol (1, 3 and 5 percent concentration) or monoglyceride (0.1, 0.3 and 0.5 percent concentration) and freezing were carried out at different drying temperatures (70ํ, 80ํ, and 90 ํC) at an absolute pressure of 7 kPa to investigate the drying kinetics and quality of potato chips in terms of colors, texture (hardness, crispness and toughness) and microstructure. Regarding the drying kinetics the drying temperature was found to have an effect on the moisture reduction rate of the samples. It was found that combined blanching and freezing pretreatments could improve the drying kinetics of potato chips comparin g with those of blanched-only samples (control). The samples immersed in chemical solutions (glycerol and monoglyceride) required longer drying time than the blanched-frozen sample. However, the effects of different pretreatments were less when the drying temperature was higher. In terms of quality the chips dried at 90 ํC had significant redness, hardness, crispness, toughness and microstructure from those dried at 70?C but were not significantly different from those dried at 80 ํC. These parameters were also found to be more satisfactory at higher drying temperatures except for the case of redness. Considering the results both in terms of the drying behavior and the dried product quality, LPSSD at 90 ํC and combined blanching and freezing pretreatments were proposed as the most favorable conditions for drying of potato chips