2011 Annual Report
1a.Objectives (from AD-416)
To develop an unfried french fry using infrared heating. The objectives are (1) to study the effect of IR dry-blanching on fat content and quality of French fries and (2) to develop a new processing method by using IR heating without oil frying for producing healthy French fries. The results of this proposed project will provide important information on new processing methods for producing low fat French fries, which could be used by the food processing industry and will ultimately promote human health.
1b.Approach (from AD-416)
Before starting the experiment, a trip to a manufacturer of French fries will be realized to further discuss the challenges we face during current production practices. Potatoes will be either purchased from a local store or provided by suppliers suggested by Washington Potato Commission. They will be cut into French fries with the size of 3/8" square for the study. To produce the blanched-fried fries, blanching of French fries will be performed with infrared radiation heating at different intensities and different residence times. Then the samples will be partially fried and frozen quickly with liquid nitrogen. The enzyme activity, color, weight loss and texture will be measured after the blanching. The processing conditions will be optimized in terms of quality and enzyme reductions and then the frozen fries produced with optimized conditions will be fried by immersion frying to produce finished French fries. The oil content, final color and texture of French fries will be compared with hot water blanched and fried French fries. Sensory analysis will also be conducted in order to analyze the consumer’s perceptions on IR-blanched and oil-fried samples. Selected commercial samples will be used for comparison.
To produce non-fried French fries, IR heating will be used for both blanching and finish frying. To reduce the IR heating time in the finishing stage, blanched fries may be partially fried with IR heating to different degrees. To improve the flavor and sensory quality, oil will be sprayed to the fry surfaces in different heating stages. The optimized amount of oil sprayed and spraying stage will be determined. Sensory analysis will also be conducted in order to analyze the consumers' perceptions of IR fried samples.
We investigated the effectiveness of infrared heating for blanching of French fries for replacing water/steam blanching. It has been discovered that infrared heating needs much less time to inactivate the enzymes compared to conventional blanching methods and should be more environmentally friendly since no water is used and no wastewater is generated. The finished French fries had much less fat content and can be considered as healthy French fries. This new processing method of French fries should bring many benefits to the food industry and consumers.