Development of natural preservatives for the food industry: an integrated strategy focused on the use of sustainable, low cost and efficient processes

Introduction: The demand for natural foods is increasing, since the concern about the use of artificial additives is increasing too. In the search for alternatives to the synthetic ones, natural preservatives obtained from plants appears as a viable option, ensuring consumer´s safety. Objectives: The aim of the present work was to evaluate the preservative capacity of natural matrices such as rosemary ( Rosmarinus officinalis L.), basil ( Ocimum basilicum L.) and sage ( Salvia officinalis L.) and compare their behavior with an artificial one (potassium sorbate). These preservatives were incorporated in yogurts and the physical parameters and nutritional profile were accessed. Results: Carbohydrates and proteins were the major nutrients. Very little influence was found among the different preservative types. The passage of time showed higher influence than the preservative types. The yogurts became lighter with the passage of time, with significative difference from 0 to 7 days, but no difference between 7 and 14 days. Inversely, the a* showed a tendency to the red over time, with significant difference from the seventh to the fourteenth day. Water activity increased over time and also showed a significant increase from the control sample to the ones with preservatives, with no significative differences between potassium sorbate and the natural preservatives. Conclusions: The natural preservatives do not show deep changes on the nutritional profile, and, pending their efficacy on antioxidant activity, should be encouraged as alternatives to synthetic preservatives. There are no significant differences between the natural preservatives and potassium sorbate, even though changes to the yogurts are very slight, as expected from food additives.