Oxygen-absorbent composition comprising a silica matrix that encapsulates fatty acids, unsaturated esters or compounds containing same, and method for producing said composition

An oxygen-absorbent composition that protects packed products that are susceptible to oxidation comprising:

• (i) an encapsulating porous silica matrix;
• (ii) a composition that contains an oxygen-absorbent compound selected from the group consisting of linseed oil, methyl oleate, methyl linoleate and soybean lecithin,
• wherein the composition (ii) is encapsulated in the porous silica matrix (i), wherein the oxygen-absorbent composition is obtained by
• (a) forming an aqueous suspension comprising the oxygen-absorbent compound having a concentration of 67-133 kg/m3;
• (b) while stirring continuously, adding an amount of silicate precursor to a solution of acid with an acid concentration between 1M and 5M until a maximum pH of 2 is reached, wherein the amount of silicate precursor is 22-56 kg per cubic meter of the solution of acid;
• (c) adding the aqueous suspension obtained in step (a) to the solution obtained in step (b);
• (d) adding additional silicate precursor to the solution obtained in step (c), obtaining a gel with a pH between 6 and 9, wherein the silicate precursor is added in a ratio of 10-40 kg of solution of silicate precursor per cubic meter of the solution of acid;
• (e) leaving the gel obtained in step (d) to stand for 1 to 48 hours;
• (f) washing the gel with water, removing the salts that result from the neutralization reaction;
• (g) drying the gel obtained;
• and
• (h) submitting the dried gel obtained in step (g) to operations of size reduction and homogenization for 30-180 minutes to obtain particles with a size less than 45 micrometers.