Phenolipids from Gallic Acid: Improvement of the Antioxidant Stability of Food Emulsionated Products.
González M. J.a ,Morales, J. C.b, Lucas, R.b,. and Medina I. a
aInstituto de Investigaciones Marinas, CSIC, Vigo, Spain
bInstituto de Investigaciones Químicas, CSIC – Universidad de Sevilla; Sevilla, Spain. mjgp @iim.csic.es

Oil in Water emulsions are multiphase systems very susceptible to lipid oxidation in which free radicals as well as volatile compounds are generated and affect the organoleptic properties of the emulsion, as well as its stability. Particularly, those based in fish oil enriched with polyunsaturated fatty acid w3 such EPA (22:5w3) and DHA (22:6w3). In the last years, several natural antioxidant compounds have been suggested for inhibiting the risk of oxidation of fish oil based functional foodstuffs enhancing the bioactive properties of the final commercial product. Particular attention has been focused on gallic acid. It is well known the antioxidant potential of this compound and its derivatives as well as to cause apoptosis in various tumor cell lines. Possible incorporation into various formulations as antioxidant in many cases has the disadvantage of low solubility in the matrix so increasing its lipophilicity can extend its use as an antioxidant in functional foods and cosmetics which incorporate in their formulation fish oil. 
So, the aim of this work is the design of phenolipids from gallic acid which show different chemical and physical properties in order to improve the antioxidant stability of food emulsionated products based in fish oil.
Methods: The antioxidant effectiveness of gallic acid and its derivatives were checked in fish oil emulsions. Oxidation was determined in thermal controlled experiments. 
Result and Discussion: All alkyl derivatives showed better antioxidant properties than gallic acid. Medium size glucosyl derivatives showed similar antioxidant behavior than gallic acid.