Solid fat content SFCSolid Fat Content refers to the amount of fat that appears as a solid state at a certain temperature.

Natural oils are generally a mixture of solid and liquid oils at room temperature. Solid fat content (SFC) is a conventional measurement index for cocoa butter, margarine, butter, and other fats, which is an indicator of the melting and hardness properties of fats at different temperatures. The melting and hardness properties have a significant impact on the taste, aroma, and application performance.

Solid fat content SFC direct testing method (desktop nuclear magnetic resonance):

The national standard GB/T 31743-2015 selects nuclear magnetic resonance direct method as the testing standard for solid fat content. The test uses free induction decay sequence (FID) and NMR direct method to determine the solid fat signal and liquid fat signal in the sample. After calculation and processing, the solid fat content SFC is obtained.

(Desktop NMR) Solid Fat Content SFC Testing Principle：

The H in solid and liquid fats exhibits completely different characteristics in the FID decay curve due to their different forms of existence. As shown in the figure below, the solid fat signal decays rapidly, usually by 70 microseconds. The attenuation of liquid fat signal is slow, and it is generally believed that it has not been lost at 70 microseconds. However, there is a specific dead time for the acquisition of nuclear magnetic resonance signals, so when we collect the FID first point signal S after the dead time, a part of the solid fat signal has already decayed during the dead time (S' - S). Solid fat content SFC can be obtained through certain signal processing.