Determination of free fatty acids in beer

Abstract

Free fatty acids (FFA) content of beer affects the ability to form a stable head of foam and plays an important role in beer staling. Moreover, the presence of saturated FAs is related sometimes to gushing problems in beer. The aim of this research was to validate an analytical method for the determination of FFAs in beer. The extraction of FFAs in beer was achieved via Liquid-Liquid Cartridge Extraction (LLCE), the FFAs extract was purified by Solid Phase Extraction (SPE), methylated by boron trifluoride in methanol, and injected into GC-FID system. The performance criteria demonstrate that this method is suitable for the analysis of medium and long chain FFAs in beer. The proposed method was tested on four experimental beers.

Keywords: Analysis; Beer; Capric acid (PubChem CID: 2969); Caprylic acid (PubChem CID: 379); Free fatty acids; GC-FID; LLCE; Lauric acid (PubChem CID: 3893); Linoleic acid (PubChem CID: 5280450); Linolenic acid (PubChem CID: 5280934); Myristic acid (PubChem CID: 11005); Myristoleic acid (PubChem CID: 5281119); Oleic acid (PubChem CID: 445639); Palmitic acid (PubChem CID: 985); Palmitoleic acid (PubChem CID: 445638); SPE; Stearic acid (PubChem CID: 5281).