Producing lower-calorie deep fat fried French fries using infrared dry-blanching as pretreatment

• Published in: Food chemistry 2012-05, Vol.132 (2), p.686-692
• Main Authors: Bingol, Gokhan, Zhang, Ang, Pan, Zhongli, McHugh, Tara H.
• Format: Article
• Language: English
• Subjects: Biological and medical sciences; catechol oxidase; color; Colour; deep fat frying; Enzyme; Fat industries; Food industries; French fries; Fundamental and applied biological sciences. Psychology; Health; heat inactivation; Oil; oils; Sensory; sensory evaluation; taste; temperature; texture; water content
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2011.10.055

► Infrared heat successfully inactivated polyphenol oxidase enzyme in 3min. ► Oil uptake of French fries was significantly reduced. ► No significant difference in sensory properties of infrared dry-blanched and unblanched fries. The main objectives of this work were to study the suitability of using infrared (IR) heating as a dry-blanching pretreatment prior to frying and to investigate its potential to reduce the oil uptake in French fry production. It was observed that by using IR heat complete inactivation of polyphenol oxidase enzyme could be achieved in 3min with 4.7% moisture loss for 9mm French fries. Following IR dry-blanching, the samples were fried at 146, 160, and 174°C for 1, 3, 5, and 7min. At the end of 7min frying, compared to unblanched samples, dry-blanched samples had 37.5%, 32% and 30% less total oil at the frying temperatures of 146, 160 and 174°C, respectively. The final moisture contents of unblanched and dry-blanched samples were between 50% and 60% after 7min frying. The L*a*b* colour values of both unblanched and dry-blanched samples decreased initially and then increased as the frying progressed. The sensory evaluation revealed that panelists mostly favored the IR dry-blanched French fries in terms of taste, texture, colour and appearance.