3.3. Microbiological quality
In order to verify the safety of the proposed process, samples of the final product were submitted to microbiological analysis. The determination of the microbiological quality of the products was performed through the total count of aerobic mesophilic bacteria, lactic acid bacteria and fungi and yeast as indicators of the hygienic quality of the product and the process applied. In the present work, count results indicated that the mesophilic aerobic bacteria and lactic acid bacteria populations were around 103 CFU/g, while fungi and yeasts count was below 100 CFU/g. There were no significant differences between all systems evaluated for the corresponding microbial counts. It is important to remark that the total counts of mesophilic aerobic bacteria and fungi and yeast were lower than those ruled as maximum values (5 × 104 CFU/g and 103 CFU/g, respectively) in the Argentine Food Code for Dietary Foods for Special Dietary Uses (ready-to-eat products). These results indicate that hygienic processing together with the antimicrobial barriers applied (low pH, aw reduction, potassium sorbate addition) contributed to the safety of the final product.
4. Conclusion
In the present research, a refrigerated ready-to-eat food fortified with Fe and AA was successfully prepared using pumpkin (Cucurbita moschata Duchesne ex Poiret) as raw material applying a dry infusion process. Final products fortified with AA and Fe resulted with adequate quality from color and microbiological view point under the conditions herein assayed. Water content as well as water activity of the final product was affected by the type of coating and the process applied. AA retention was also strongly affected by the aw of the final product and application of edible coating improved AA stability. The Fe supported in the coatings tended to have a higher bioaccessibility at in vitro simulated lumen conditions. It is important to remark that mineral content must be adjusted for the required limits established by regulations.
Acknowledgments
This research work received financial support from the University of Buenos Aires (UBACyT 20020110200192 and 20020090200693), The National Agency of Scientific and Technological Promotion of Argentina (ANPCyT PICT-2005-38239) and The National Scientific and Technical Research Council of Argentina (CONICET, PIP11220090100531 and PIP20020100100700).