Using Infrared Radiation in a Radiant Wall Oven for Blanching Small-Sized Peanuts

Abstract

The main objective of this study was to determine the effectiveness of infrared technology for blanching small-sized peanuts. A radiant wall oven was used for infrared blanching. Infrared treatments included 343°C for 60 s and 288°C for 90 s. High and low moisture groups with approximate moisture content of 9% and 6% were used. An impingement oven set at 100°C for 20 min was used as the control treatment. No treatment differed from control in terms of blanchability. A descriptive sensory shelf life study of six weeks found no evidence of oxidative changes in experimental treatments. The infrared blanched peanuts were roasted using an impingement oven set to 177°C for 10 min for a consumer acceptability test. Conventionally blanched peanuts roasted under the same parameters were used as a control. The consumer panel found the peanuts blanched by infrared radiation at 343°C for 60 s to be the most likeable roasted IR sample and did not differ from control. IR heating is a viable and quicker alternative to blanch small-sized peanut varieties with minimal effects on quality including sensory properties.