Characterization of crispness of French fries by fracture and acoustic measurements, effect of pre-frying and final frying times

The influence of pre-frying and final frying time on the crispness of French fries was evaluated by simultaneous analysis of the fracture and acoustic properties during instrumental simulation of human chewing. The analysis of the frequency distribution of the force and sound events corresponding to the crust of the French fry reflected an effect of both pre-frying and final frying time on instrumental crispness. Up to 60 s pre-frying, an increase in the number and magnitude of force and sound events was found, which reflect an increase in crispness. The increase in final frying time increased crispness, but it cannot counterbalance a lack of pre-frying. The moisture content of the whole French fries cannot explained the effect of pre-frying on crispness. Conversely, the effect of pre-frying can be explained when considering only the moisture content of the crust. Pre-frying may allow an easier loss of water from the crust during final frying, which will enhance its crispness.