Abstract:

The spectral and physico-chemical properties of the pigments extracted from the fruits of Padus racemosa and largefruit and small-fruit species of Padus virginiana were investigated in order to offer helpful references for the development and utilization of these pigments. The results showed that the all these pigments from different Padus L. plants had good resistance to light and heat but were sensitive to pH value, oxidants and reductants. The pigment from Padus racemosa exhibited higher resistance to oxidation and reduction but poorer resistance to light when compared with that from large-fruit species of Padus virginiana, while the resistance of both of them to light, heat, oxidation and reduction was weaker than that of the pigment from small-fruit species of Padus virginiana. Except Fe2+, Fe3+ and Cu2+, other metal ions including Na+, Ca2+, Zn2+, Al3+, Mg2+,NH4+, Ba2+ and Mn2+ had no adverse effect on all these pigments. Citric acid as a common food additive had hyperchromic effect on them, while two others, ascorbic acid and sodium benzoate had hypochromic effect. Sucrose and glucose had no significant effect.

Key words: Padus racemosa, Padus virginiana, pigment, physico-chemical properties