Vacuum impregnation and osmotic dehydration in matrix engineering

Health benefits are one of the specific issues that will greatly influence the food industry in the next few years. Functional foods are products that may provide a health benefit beyond the traditional content of nutrients, or through other added physiologically active components (PAC). Fruits and vegetables are increasingly being consumed because of their appreciated nutritional and fresh properties. The enrichment of these products with minerals, vitamins or other PAC can be a good choice to develop functional foods. Vacuum impregnation (VI) allows to introduce controlled quantities of a solution in the porous structure of fruit and vegetable (matrix). This solution can contain PAC, aw or pH depressors, antimicrobials, etc., in order to formulate functional, stable, fresh-like products. The feasibility of VI for a great quantity of fruits and vegetables is discussed by means of analysing their response to VI. Porosity and VI effectiveness of impregnated products were observed by Cryo-SEM. A model to determine the concentration level of PAC in the impregnating solution was established in order to formulate functional foods with different calcium and iron salts which could represent a determined percentage of the recommended daily intake of these minerals.