Fatty acid composition of margarines

Area of Science:

• Food Science
• Nutritional Chemistry
• Analytical Chemistry

Background:

• Margarine's fatty acid profile is crucial for its nutritional value.
• Variations in processing can significantly alter fatty acid composition.
• Accurate assessment of fatty acids like linoleic acid is important for consumers.

Purpose of the Study:

• To determine the fatty acid composition of various margarines.
• To compare analytical methods for quantifying polyunsaturated fatty acids.
• To evaluate the accuracy of product labeling regarding fatty acid content.

Main Methods:

• Analysis of 86 margarine samples (bar, tub, liquid) from Canada and the US (1973-1974).
• Gas-liquid chromatography (GLC) for total polyunsaturated fatty acids.
• Enzymatic method using lipoxidase for comparison with GLC results.

Main Results:

• Significant variations in fatty acid composition and ratios were observed across samples.
• Soft (tub) margarines generally contained higher levels of linoleic acid than hard (bar) margarines.
• Product labeling was not consistently reliable for identifying high linoleic acid content.

Conclusions:

• Margarine fatty acid profiles vary considerably, impacting nutritional quality.
• Gas-liquid chromatography and enzymatic methods provide comparable results for polyunsaturated fatty acids.
• Consumers may not be accurately informed about linoleic acid content through current product labeling.