Development and validation of a rapid method for the determination of oil and oleic acid content in peanut (Arachis hypogaea L.) using time domain nuclear magnetic resonance

Abstract

Peanuts (Arachis hypogaea L.) are an important nut product used in various cuisines worldwide. Many different analytical procedures are in place to ensure its nutritional properties including total oil content and oleic acid content which stand out among the most important parameters for assessing the nutritional quality of the kernels as well as their shelf-life. The analytical procedures for the determination of these two properties are extremely laborious and time-consuming. We developed and validated two methods using Time Domain-Nuclear Magnetic Resonance (TD-NMR) for the determination of these parameters in less than 5 min without any need for sample preparation. The methods were validated and tested with samples from different sources and profiles, ensuring fitness-for-purpose with good repeatability and trueness in all cases. The developed and validated method for determination of oleic acid fraction using multivariate calibration was embedded on a web-based application that allows easy use with very limited personnel training and a calibration transfer approach was developed to allow for this model to be used on a different instrument, therefore both methods are readily applicable for commercial and research peanut samples.