Aminas bioativas em molho de soja: validação de método e ocorrência

Abstract

BIOACTIVE AMINES IN SOY SAUCE: METHOD VALIDATION AND OCCURRENCE. The objective of this work was to determine the profile and levels of biogenic amines in Brazilian soy sauce from the retail market of Belo Horizonte/MG. An ion pair-HPLC method with post column derivatization with OPA and fluorimetric detection for the determination of biogenic amines in soy sauce was validated. The method was linear, precise and accurate for putrescine, cadaverine, histamine, tyramine and phenylethylamine, which are usually found at high levels in soy sauces. Detection and quantification limits were appropriate for the analysis. There was a significant effect of the matrix on the analysis. The optimum conditions for the extraction of amines were 6 mL of sample, 15 mL of TCA 5%, 4 minutes of agitation and no centrifugation was required. The amines found in the samples were: putrescine (97.6%), cadaverine (28.6%), histamine (78.6%), tyramine (100%) and phenylethylamine (57.1%). The total level of amines ranged from 14.52 to 775.94 mg/L. Tyramine contributed the most to total amine levels. Brands B, D, E, F and G had more than 60% of the samples with histamine and tyramine and more than 30% of the samples with phenylethylamine contents higher than the toxic limit suggested, values capable of causing adverse health effects. The concentrations of the biogenic amines were: putrescine nd to 180.0 mg/L; cadaverine nd to 68.6 mg/L; histamine nd to 395.0 mg/L; tyramine 3.0 to 659.9 mg/L; and phenylethylamine nd to 121.9 mg/L. The pH of the samples ranged from 4.0 to 5.2; the acidity from 290.6 to 1312.9 meq/L and the soluble solids content ranged from 22 to 30 °Brix. There was a significant correlation between acidity and the putrescine, histamine, tyramine and phenylethylamine concentration. Putrescine presented a significant correlation only with phenylethylamine. There was a significant correlation among cadaverine, histamine, tyramine and phenylethylamine.KEY WORDS: soy sauce; amines, quality; HPLC.