Rosmarinic acid has been shown to be a versatile antioxidant [2] acting on a wide range of reactive oxygen species including superoxide, hydroxy radicals and inhibiting lipid peroxidation induced by the peroxyl radical. [3]
In alcoholic and non-alcoholic beverages oxidation is responsible for flavour degradation and for flavour and colour degradation in wine ultimately leading to product staling and reduced shelf life. AquaROX 5® provides a water soluble formulation that offers a real solution in both alcoholic and non-alcoholic beverages
At typical dosage levels in alcoholic or non-alcoholic beverages AquaROX 5® has no discernible impact on the flavour or aroma of the end product, but provides a powerful antioxidant that keeps products fresher by retarding oxidation . In beer and wine sulphur dioxide has traditionally been used as an antioxidant either produced naturally during fermentation or added where this is permitted. Reduction of sulphur dioxide in both products is desirable and AquaROX 5® can be used to eliminate the addition of sulphur dioxide or reduce its use significantly.
Using extracts from the Lamiaceae family such as rosemary [4] in beer has been shown to be effective in improving flavour shelf life both by organoleptic assessment and by a variety of analytical methods. In particular it has been shown that rosmarinic acid:
Oxidation of beer components is a widely debated subject due to the complexity of the product and the mechanism for these effects is not clearly understood. Since individual processes differ so widely AquaROX 5® should be tried at various points in the brewing process. Typical dose rates are 2 -5ppm rosmarinic acid in finished product and possibly slightly higher for intermediate process addition.
In recent years flavoured alcoholic beverages have become a part of brewery production and these are also susceptible to flavour oxidation. The first example of this [5] was the use of plant extracts rich in rosmarinic acid to prevent the degradation of citral. Under acidic conditions in citrus beverages citral, a key component in lemon flavouring, undergoes degradation to develop off-flavours attributed to the formation of p-methylacetophenone. The addition of rosmarinic acid at levels of 2-5ppm was sufficient to significant retard the formation of degradation products and the shelf-life was significantly enhanced.
[1] Brewer M.S. Natural Antioxidants: Sources, Compounds, Mechanisms of Action, and Potential Applications. Comprehensive Reviews in Food Science and Food Safety, 2011,10,221-247
[2] Wada, M. et al., Evaluation of Quenching Effects of Non-Water-Soluble and Water-Soluble Rosemary Extracts Against Active Oxygen Species by Chemiluminescent Assay. Food Chemistry , 2004, 87(2), 261-267
[3] Wu T.T., Hwang B.R. and Cho E.J. Scavenging Effect of Extract from Perilla frutescens and Rosmarinic Acid from Free Radical and Lipid Peroxidation. J. Food Sci. Nutr., 2011, 16, 224-229
[4]WO2005027665 (A1) (2005) The use of labiatae herb preparations for extending the flavour shelf life of malt beverages
[5] US Patent 6,306,450 (2001) Storage stable, citrus flavoured compositions comprising plant extracts
