Color and texture of low-calorie peanuts as affected by a new oil extraction process named "Mechanical Expression Preserving Shape Integrity" (MEPSI)

J Food Sci Technol. 2016 Mar;53(3):1649-62. doi: 10.1007/s13197-015-2081-z. Epub 2015 Nov 5.

Abstract

The current healthy life style pushed to develop and implement a novel efficient defatting process of high quality called "Mechanical Expression Preserving Shape Integrity" that conserved the sensory, color, textural, morphological and acceptability of partially defatted roasted peanuts. In this study, Response Surface Methodology was used to investigate the best extraction parameters (initial water content, pressure and pressing duration) based on the highest Color Consumer Evaluation scores, the best colorimetric parameters (L*, a*, b*, ΔE*) and the most appealing textural attributes (Fracturability, First Fracture Work Done, First Fracture Percentage of Deformation, Rupture Force, Percentage of Deformation at Rupture). Experimental results showed that defatting promotes a lighter and neutral grain color, higher fracturability and rupture force as well as higher deformation strength. Aiming to retain most of the colorimetric and textural properties after defatting and roasting, it was found that peanuts should be hydrated to 7 % d.b. and treated at 4.74 MPa for 14.22 min.

Keywords: Arachis hypogaea; Color; Oil extraction; Optimization; Roasting; Texture.