There are few reports about the antioxidant properties of annatto (Bixa orellana), especially considering their antioxidant action in food. In this study we evaluated the antioxidant effect of annatto powder and sodium erythorbate on lipid oxidation in pork loin patties by measuring the secondary products of lipid oxidation, the changes in the fatty acid composition, cholesterol oxidation, and the extent of bixin degradation during storage at - 18. °C for 120. days and subsequent thermal treatment. Sodium erythorbate (0.1%) and annatto (0.05%), used alone or in combination, were able to reduce the formation of thiobarbituric acid reactive substances and cholesterol oxidation after thermal treatment when compared with pork patties without antioxidant (control). Bixin degradation was less pronounced in the patties containing annatto (0.05%) + sodium erythorbate (0.1%), suggesting that sodium erythorbate protected this carotenoid from degradation. The addition of annatto, sodium erythorbate or annatto + sodium erythorbate did not have any impact on SFA, MUFA and PUFA oxidation regardless thermal treatment or storage. The cholesterol contents did not change during storage however, there was a significant loss of 15% due to thermal treatment.65PB137143(1997) Official methods of analysis, , Association of Official Analytical Chemists, Washington, DC(1997) Official methods and recommended practices of the American oil chemists' society. Official Method Ce 1b-89, , American Oil Chemists' Society Press, Champaign, D. Firestone (Ed.)Baggio, S.R., Bragagnolo, N., Fatty acids, cholesterol oxides and cholesterol in Brazilian processed chicken products (2006) Italian Journal of Food Science, 18, pp. 199-208Baggio, S.R., Bragagnolo, N., Cholesterol oxide, cholesterol, total lipid and fatty acid contents of processed meat products during storage (2006) LWT- Food Science and Technology, 39, pp. 513-520Baggio, S.R., Bragagnolo, N., The effect of heat treatment on the cholesterol oxides, cholesterol, total lipid and fatty acid contents of processed meat products (2006) Food Chemistry, 95, pp. 611-619Barriuso, B., Otaegui-Arrazola, A., Menéndez-Carreño, M., Astiasarán, I., Ansorena, D., Sterols heating: Degradation and formation of their ring-structure polar oxidation products (2012) Food Chemistry, 135, pp. 706-712Bigolin, J., Weber, C.I., Alfaro, A.T., Lipid oxidation in mechanically deboned chicken meat: Effect of the addition of different agents (2013) Food and Nutrition Sciences, 4, pp. 219-223Bittencourt, C., Felicissimo, M.P., Pireaux, J.J., Houssau, L., ToF-SIMS characterization of thermal modification of bixin from Bixa orellana fruit (2005) Journal of Agricultural and Food Chemistry, 53, pp. 6195-6200Box, G.E.P., Hunter, W.G., Hunter, J.S., (1978) Statistics for experiments: An introduction to designs, data analysis and model building, , Wiley, New YorkBragagnolo, N., Danielsen, B., Skibsted, L.H., Effect of rosemary on lipid oxidation in pressure-processed, minced chicken breast during refrigerated storage and subsequent heat treatment (2005) European Food Research and Technology, 221, pp. 610-615Bragagnolo, N., Rodriguez-Amaya, D.B., Simultaneous determination of total lipids, cholesterol and fatty acids in meat and backfat of suckling and adults pigs (2002) Food Chemistry, 79, pp. 255-260Castro, W.F., Mariutti, L.R.B., Bragagnolo, N., The effects of colorifico on lipid oxidation, colour and vitamin E in raw and grilled chicken patties during frozen storage (2011) Food Chemistry, 124, pp. 126-131Chisté, R.C., Mercadante, A.Z., Gomes, A., Fernandes, E., Lima, J.L.F.C., Bragagnolo, N., In vitro scavenging capacity of annatto seed extracts against reactive oxygen and nitrogen species (2011) Food Chemistry, 127, pp. 419-426Chisté, R.C., Yamashita, F., Gozzo, F.C., Mercadante, A.Z., Simultaneous extraction and analysis by high performance liquid chromatography coupled to diode array and mass spectrometric detectors of bixin and phenolic compounds from annatto seeds (2011) Journal of Chromatography, 1218, pp. 57-63Folch, J., Lees, M., Stanley, S., A simple method for the isolation and purification of total lipids from animal tissues (1957) Journal of Biological Chemistry, 226, pp. 497-509Global outlook global market, p. 129. , http://www.fao.org/docrep/016/al993e/al993e00.pdf, retrieved from:, (accessed 10/10/2013)Hur, S.J., Park, G.B., Joo, S.T., Formation of cholesterol oxidation products (COP's) in animal products (2007) Food Control, 18, pp. 939-947Joseph, J.D., Ackman, R.G., Capillary column gas chromatographic method for analysis of encapsulated fish oils and fish oil ethyl esters: collaborative study (1992) Journal of AOAC International, 75, pp. 488-506Kim, S.K., Nawar, W.W., Parameters influencing cholesterol oxidation (1993) Lipids, 28, pp. 917-922Lee, S., Decker, E.A., Faustman, C., Mancini, R.A., The effects of antioxidant combinations on color and lipid oxidation in n3 oil fortified ground beef patties (2005) Meat Science, 70, pp. 683-689Mariutti, L.R.B., Nogueira, G.C., Bragagnolo, N., Optimization and validation of analytical conditions for cholesterol and cholesterol oxides extraction in chicken meat using response surface methodology (2008) Journal of Agricultural and Food Chemistry, 56, pp. 2913-2918Mariutti, L.R.B., Nogueira, G.C., Bragagnolo, N., Solid phase microextraction gas chromatography for the evaluation of secondary lipid oxidation products in chicken patties during long-term storage (2009) Journal of the Brazilian Chemical Society, 20, pp. 1849-1855Mariutti, L.R.B., Nogueira, G.C., Bragagnolo, N., Lipid and cholesterol oxidation in chicken meat are inhibited by sage but not by garlic (2011) Journal of Food Science, 76, pp. 909-915Park, S.W., Addis, P.B., Further investigation of oxidized cholesterol derivatives in heated fats (1986) Journal of Food Science, 51, pp. 1380-1381Preston, H.D., Rickard, M.D., Extraction and chemistry of annatto (1980) Food Chemistry, 5, pp. 47-56Ramalho, V.C., Jorge, N., Antioxidantes utilizados em óleos, gorduras e alimentos gordurosos (2006) Quimica Nova, 29, pp. 755-760Reische, D.W., Lillard, D.A., Eitenmiller, R.R., Antioxidants (2002) Food lipids: Chemistry, nutrition and biotechnology, pp. 489-516. , Marcel Dekker, New York, C.C. Akoh, D.B. Min (Eds.)Ribani, M., Bottoli, C.B.G., Collins, C.H., Jardim, I.C.S.F., Melo, L.F.C., Validação em metodologia cromatográfica e eletroforéticos (2004) Quimica Nova, 27, pp. 771-780Rodrigues, E., Mariutti, L.R.B., Chisté, R.C., Mercadante, A.Z., Development of a novel micro-assay for evaluation of peroxyl radical scavenger capacity: application to carotenoids and structure-activity relationship (2012) Food Chemistry, 136, pp. 1-10Rodrigues, E., Mariutti, L.R.B., Mercadante, A.Z., Scavenging capacity of marine carotenoids against reactive oxygen and nitrogen species in a membrane-mimicking system (2012) Marine Drugs, 10, pp. 1784-1798Rodrigues, S.M., Soares, V.L.F., Oliveira, T.M., Gesteira, A.S., Otoni, W.C., Costa, M.G.C., Isolation and purification of RNA from tissues rich in polyphenols, polysaccharides, and pigments of annatto (Bixa orellana L.) (2007) Molecular Biotechnology, 37, pp. 220-224Rodriguez-Estrada, M.T., Penazzi, G., Caboni, M.F., Bertacco, G., Lercker, G., Effect of different cooking methods on some lipid and protein components of hamburgers (1997) Meat Science, 45, pp. 365-375Saldanha, T., Sawaya, A.C.H.F., Eberlin, M.N., Bragagnolo, N., HPLC separation and determination of 12 cholesterol oxidation products in fish: comparative study of RI, UV and APCI-MS detectors (2006) Journal of Agricultural and Food Chemistry, 54, pp. 4107-4113Sancho, R.A.S., Lima, F.A., Costa, G.G., Mariutti, L.R.B., Bragagnolo, N., Effect of annatto seed and coriander leaves as natural antioxidants in fish meatballs during frozen storage (2011) Journal of Agriculture and Food Science, 76, pp. 838-845Tsuruma, K., Shimazaki, H., Nakashima, K., Yamauchi, M., Sugitani, S., Shimazawa, M., (2012) Molecular Nutrition & Food Research, 56, pp. 713-724