Enhancement of Colour Density and Anthocyanin Stabilities in Pomegranate Juice Against Hmf at Various Concentrations Through Amino Acid Copigmentation During Storage

Abstract

Degradation effect of various 5-hydroxymethylfurfural (HMF) concentrations (2.3–15.2 mg/L) on pomegranate juice (PJ) anthocyanins/colour and potential of amino acids [aspartic acid (AA), phenylalanine (PA) and valine (V)] to reduce anthocyanin degradation by copigmentation were investigated. Stabilities of anthocyanin and colour density (CD) were reduced by 5.2–8.2 mg HMF/L but increased by 15.2 mg HMF/L. When ratios of “cy-3,5-diglu to HMF” and “cy-3-glu to HMF” were 1.82–2.67 and 1.91–2.85, respectively, copigmentation took place. AA and V reduced HMF content. As number of –CH3 group in an amino acid increased, stability of HMF reduction effect by the amino acid also increased. In PJ containing 8.2 mg HMF/L, V, a hydrophobic-aliphatic amino acid, provided the highest stabilities for individual anthocyanins, CD and hyperchromic effect (HE). AA increased the stabilities of CD and HE in PJ containing 5.2 mg HMF/L, while PA increased CD stability at 15.2 mg HMF/L concentration.