Quantitation of Allicin in Garlic-based Products: Comparisons among Spectrophotometry, GC and HPLC

Spectrophotometric, GC and HPLC methods were used to determinate allicin concentration in garlic-based products (garlic powder, garlic oil and garlic tablets). Allicin was extracted using a mixture of water and ethanol and analyzed by the three methods. The results revealed that the GC method was unsuitable for allicin quantitation because of high coefficient of variations and high temperatures. The spectrophotometric method was the simplest and most effective method for solid garlic-based products. The HPLC method was more accurate for allicin quantitation in all garlic-based products, especially liquids. Furthermore, the HPLC method allowed the simultaneous quantitation of allicin and allicin degradation products such as diallyl sulfide, dimethyl trisulfide, diallyl disulfide and diallyl trisulfide. Based on the spectrophotometric and HPLC method, garlic oil contained the highest allicin concentration, followed by the garlic tablets and garlic powder.