Eur Food Res Technol (2007) 225:929–935 DOI 10.1007/s00217-006-0463-1 REVIEW ARTICLE Effect of pre-drying and par-frying conditions on the crispness

Abstract An experimental design was used to study the effect of pre-drying (to 10, 15 and 20 % weight loss) and par-frying conditions (160, 170 and 180 ◦C) on the crispness of French fries. Par-frying time was adjusted with a software program to obtain equal moisture content and internal texture for all samples. Crispness was evaluated with a sensory panel. Furthermore, samples were analysed with a texture analyser and with confocal scanning laser microscopy (CSLM). Par-frying at 180 ◦C resulted in a crispier product than at 160 and 170 ◦C. Pre-drying to 20 % weight loss lead to blis-ters and reduced crispness in comparison with pre-drying to 10 and 15 % weight loss. Instrumental texture measurements showed a good correlation with sensory crispness. Large dif-ferences in cell structure, such as blisters, could be observed with CSLM. CSLM was useful to explain results from the instrumental and sensory texture evaluation