Author
Bingol, Gokhan | |
Pan, Zhongli | |
BEI, WANG - University Of California | |
ZHANG, ANG - University Of California | |
McHugh, Tara |
Submitted to: Journal of Food Engineering
Publication Type: Peer Reviewed Journal Publication Acceptance Date: 8/4/2013 Publication Date: 9/11/2013 Citation: Bingol, G., Pan, Z., Bei, W., Zhang, A., McHugh, T.H. 2013. Comparison of water and infrared blanching methods for processing performance and final product quality of French fries. Journal of Food Engineering. DOI: 10.1016/j.jfoodeng.2013.08.001. Interpretive Summary: There is a strong interest in producing low fat French fries. The main objective of this work was to compare infrared blanching (IRB) with water blanching (WB) as a pretreatment method for producing lower calorie French fries. It was observed that complete inactivation of polyphenol oxidase enzyme for 9.43 mm potato strips could be achieved in 200 s and 16 min by using IRB and WB, respectively. Following the blanching, the samples were deep-fat par-fried at 174°C for 1 min and were then deep-fat finish-fried at 146, 160, and 174°C for 2, 3, 4 and 5 min. At all frying times and temperatures infrared blanched samples had less oil content than water blanched ones. The energy analysis of both blanching operations showed that energy expenditure-wise the operation cost for pre-treating French fries with IRB would be head-to-head with WB. The chromatic color components of infrared and water blanched samples were significantly (P<0.05) affected by finish-frying time and temperature and the a* and b* values for infrared blanched samples developed faster than water blanched samples during deep-fat finish frying. The results showed that IRB can be used for producing low fat French fries. Technical Abstract: The main objective of this work was to compare infrared blanching (IRB) with water blanching (WB) as a pretreatment method for producing lower calorie French fries. It was observed that complete inactivation of polyphenol oxidase enzyme for 9.43 mm potato strips could be achieved in 200 s and 16 min by using IRB and WB, respectively. Following the blanching, the samples were deep-fat par-fried at 174°C for 1 min and were then deep-fat finish-fried at 146, 160, and 174°C for 2, 3, 4 and 5 min. At all frying times and temperatures infrared blanched samples had less oil content than water blanched ones. The energy analysis of both blanching operations showed that energy expenditure-wise the operation cost for pre-treating French fries with IRB would be head-to-head with WB. The final moisture contents of infrared and water blanched samples were between 40 to 50% after 5 min of finish-frying. The chromatic color components of infrared and water blanched samples were significantly (P<0.05) affected by finish-frying time and temperature and the a* and b* values for infrared blanched samples developed faster than water blanched samples during deep-fat finish frying. |