Quantitative Measurement of the Chemical Composition of Fatty Acid of Cocoa Butter and the Isotopic Content of Glycerol Contained in Cocoa Butter by the NMR &amp;lt;sup&amp;gt;13&amp;lt;/sup&amp;gt;C from the INEPT Sequence and Characterization of the Geographical Origin of the Cocoa

Didier Diomandé,Gérald S Remaud,Silvestre Virginie,Tiemoko Touré Dro,Jacques Sagne Akpa,Illa Tea

doi:10.4236/ajac.2022.133007

Abstract

The determination of the chemical composition of cocoa butter and the isotopic contents of the carbons (C-2, C-1 and C-3) of the glycerol contained in the cocoa butter were measured by the NMR-13C from the INEPT sequence. This technique has already been applied to triglycerides of animal origin. Thus, cocoa butter is made up of nearly 66% saturated fatty acid composed mainly of stearic acid and palmitic acid. Monounsaturated fatty acids represented by oleic acid have an average content of 31% and polyunsaturated fatty acids represent less than 4%. Likewise, the isotopic contents of the glycerol of the triglycerides of cocoa butter in 13C of the carbons C-2, C-1 and C-3 were measured directly and values vary from -11‰ to -19‰ for the C-2 and from -39‰ to -41‰ for all C-1 and C-3 because of the symmetry of glycerol.

Highlights

There are two types of information that can be obtained from the 13C-NMR spectra acquired with the zgig and refocused INEPT sequences: on the one hand, information on the δ13C (‰) isotopic deviations of the two observable sites due to the symmetry of the glycerol (C-1, C-3 and C-2) and on the other hand information on the fatty acid composition of triglycerides in cocoa butter
The fatty acids mainly contained in cocoa butter are: oleic, palmitic and stearic acid
Statistical Treatment of the Data Obtained. Analysis of these results shows that the chemical fatty acid composition of cocoa butter is predominantly made up of saturated fatty acids, followed by the monounsaturated ones

Summary

Introduction

Unsaturated fatty acids, in particular oleic acid and linoleic acid, play an essential nutritional role They have a preventive action against cardiovascular disease by lowering cholesterol levels, which is not the case for certain saturated fatty acids [4]. It is in this sense that this work is part of the determination of the fatty acid composition and of the determination of the 13C isotopic signature of the glycerol contained in cocoa butter by the 13C-INEPT method. This technique has already made it possible to analyze triacylglycerols in olive oil and to quantify several fatty acids, triglycerols in egg yolks [6]

Methods

Results

Conclusion