Quantitative Analysis of Fat in Mayonnaise by Reflectance Spectroscopy and Multivariate Analysis

Introduction

Mayonnaise is one of various seasonings that are used on a daily basis. Reflecting the health consciousness that is prevalent in recent years, fat content-adjusted mayonnaise products have been sold in great quantities. Accordingly, it is important that the fat content listed on the label reflect the fat content determined through accurate measurement. Fat content in mayonnaise is typically determined using the Soxhlet extraction method. However, the process involving the repeated evaporation of solvent required to extract the target substance is quite time consuming. We therefore investigated a simple method based on reflectance measurement for this fat quantitation. Combining reflectance measurement using a screw-cap vial with multivariate analysis, we demonstrated the ease with which fat quantitation can be accomplished. Multivariate analysis was conducted using both multiple regression and the PLS method, and the quantitative accuracy was compared between the two methods. Both methods were found to provide good results. Furthermore, good quantitative accuracy using both the multiple regression and the PLS method were obtained even when the original mayonnaise containers were used "as is." Here, we introduce the results of this investigation.

November 25, 2025 GMT