Anthocyanins stability

The anthocyanin stabilities of grape-marc, elderberry, and black currant extracts were lower in all sucrose (100 g/L)-added systems as compared to the controls at pH values of 3, 4, and 5, whereas the brown index did not change with the addition of sugar. On the contrary, a protective effect of 20% sucrose added to frozen crowberries and strawberries was reported and the stabilities of anthocyanin juices from aronia were higher in syrups than in diluted extracts. Roselles pre-... 

Figure 9.4.3 A metalloanthocyanin, a metal complex of anthocyanin stabilized through the association of a metal ion with two hydroxy groups oriented ortho to one another on the anthocyanin ring.

Nymphaea caerulea, for seven natural anthocyanins stabilizing a DNA triplex, etc. Sequential analysis of the oligosaccharide structures of the flavonol tamarixetin-7-O-rutino-side has been performed by ID multistep-relayed COSY-ROESY experiments. Selective excitation was performed by Gaussian-shaped soft pulses. 

It is known that polyacylated anthocyanins are very stable in neutral or weakly acidic aqueous solutions, whereas simple anthocyanins are quickly decolorized by hydration at the 2-position of the anthocyanidin nucleus. The shift to blue colors and increased anthocyanin stability are in many cases simply achieved by intramolecular copigmentation involving... 

Rodriguez-Saona, L. E., Wrolstad, R. E., Pereira, C. (1999). Glycoalkaloid content and anthocyanin stability to alkaline treatment of red-fleshed potato extracts. J. Food Scl, 64,445 50. 

Woodward, G. Kroon, P. Cassidy, A. Kay, C. 2009. Anthocyanin stability and recovery implications for the analysis of clinical and experimental samples. J. Agric. Food Chem. 57 5271-5278. 

The stability of anthocyanins may be viewed from the perspective of their importance as endogenous components of berry fruits and their products. In addition, a number of anthocyanin extracts are used as food colorants and may be added to various products at different stages during food processing. Several reviews of anthocyanin stability have been published over the years (Markakis, 1982 Jackman et al., 1987a Henry, 1996 Jackman and Smith, 1996 Wrolstad, 2000). 

Substitution patterns of the flavan nucleus along with glycosidation and acylation patterns influence anthocyanin stability of grapes and berry fruits to some extent. 

A detailed study of the effects of pH on anthocyanin stability has been presented by Cabrita et al. (2000). Buffered solutions in the range of pH 1-12 of the 3-glucosides of the six common anthocyanidins were stored in the dark over a 60-day period at 10°C and 23°C. Under strong acidic conditions (pH 1-3), more than 70% of the initial concentration remained after 60 days at 10°C for all anthocyanins, while considerable losses (>90%) occurred at pH 5-6 even after 8 days. Similar stability patterns occurred at the higher temperature of 23°C, although the rates of anthocyanin degradation were higher, and only 40% of the initial anthocyanins were detectable after 60 days. 

Several studies have shown that anthocyanin stability increases with decreased water content, i.e., decreasing water activity (aw) (Wrolstad, 2000). Dry anthocyanin powders (aw < 0.3) are stable for several years when stored in hermetically sealed containers (Jackman and Smith, 1996). This property is advantageous when anthocyanins are produced into dry products and powders. Zajac et al. (1992) reported anthocyanin losses of 14% after 15 months of storage of a dry powder from black currant extracts at 20°C. When starch syrup or maltodextrins were included as carriers during the drying of the extracts, the anthocyanin losses were reduced to 2% and 3%, respectively. 

Garcia-Viguera, C., Zafrilla, R, Artes, F., Romero, F., Abelian, P, and Tomas-Barberan, F.A. 1998. Colour and anthocyanin stability of red raspberry jam. J. Sci. Food Agric. 78 565-573. 

Lenoble, R., Richheimer, S.L., Bank, V.R., and Bailey, D.T. 1999. Pigment composition containing anthocyanins stabilized by plant extracts. US 5,908,650. (FSTA 1999-11-A1880). 

INFLUENCE OF THE ACYL GROUP POSITION AT THE AGLYCONE ON THE ANTHOCYANIN STABILITY TO HEAT... 

Colour and anthocyanin stability of red raspberry jam. J Sci Food Agric. 78 565-573. 

Ingallinera et al. (2005) compared total pectinesterase activity of Sicilian blood oranges (Sanguinello, Moro, and Tarocco) with the blonde Navel cultivar, checking enzyme stability with various pasteurization time and temperature (70-8 5 °C) conditions in order to optimize the heat treatment and increase the shelf life of the pasteurized juice. To do this they stored the juices at 4, 15, and 25°C for times ranging between 10 minutes and 50 days. Decimal reduction time and temperature (D and z) and the kinetic constant k) were established to optimize and increase the shelf life of the pasteurized juiee. Finally, a heat treatment (85°C x 3 minutes) of both microbiological and enzymatic efficacy was developed that does not compromise anthocyanin stability. 

Kita, A. Bakowska-Barczak, A. Hamouz, K. Kulakowska, K. Lisinska, G., The effect of frying on anthocyanin stability and antioxidant activity of crisps from red- and purple-fleshed potatoes (Solanum tuberosum L.). Journal of Food Composition and Analysis (2013) 32, 169—175. 

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