Cristina Caleja

Rosemary extracts in functional foods: extraction, chemical characterization and incorporation of free and microencapsulated forms in cottage cheese

Consumers search for food with functional characteristics beyond its nutritional properties. Thus, the concept of functional food has become a hot topic, allowing us to obtain additional health benefits, including disease prevention. In this context, plants are recognized as sources of a wide range of bioactives, including phenolic compounds. Herein, rosemary aqueous extract was used as a functional ingredient for cottage cheese, after proving that it possesses both higher content of phenolic compounds and antioxidant activity, comparatively with the corresponding hydroethanolic extract. However, a decrease of bioactivity was observed for the cheese samples enriched with the extracts in free form after seven days under storage. Therefore, in order to preserve the antioxidant activity, the rosemary aqueous extract was efficiently microencapsulated by using an atomization/coagulation technique. Overall, the introduction of both free and microencapsulated extracts provided bioactivity that was better preserved with microencapsulated extracts without changing the nutritional value of cottage cheese.

Optimization and comparison of heat and ultrasound assisted extraction techniques to obtain anthocyanin compounds from Arbutus unedo L. fruits

The goal of this study was to compare anthocyanin extraction from Arbutus unedo L. fruits, by using two techniques assisted by different energy sources, heat and ultrasound. In order to obtain the conditions that maximize anthocyanin extraction, a response surface methodology was applied using the circumscribed central composite design of three variables with five levels. Three anthocyanin compounds were identified by HPLC-DAD-ESI/MS, being cyanidin-3-glucoside the main molecule. Heat assisted extraction proved to be the most effective method at 5 min, 90 °C and 80% of ethanol, yielding 51.2% of extract, with a total anthocyanin content of 382.4 µg/g dried fruit, and 744.6 µg/g extract. These response values were slightly improved by studying the solid/liquid effect at the optimal conditions in dose-response format, showing steady extraction values from 5 to 40 g/L. Results show the possibility of using A. unedo fruits as a source of anthocyanin compounds for industrial applications.

Suitability of lemon balm (Melissa officinalis L.) extract rich in rosmarinic acid as a potential enhancer of functional properties in cupcakes

Melissa officinalis (lemon balm) and its extracts have been frequently reported as possessing bioactive properties, offering the potential for use in development/enrichment of food products with additional functional capabilities, providing health benefits to consumers. The antioxidant, antibacterial and antifungal activity of lemon balm extract, as well as its potential hepatotoxicity were thoroughly evaluated. The extracts were then incorporated into cupcakes and their preserving effect, chemical composition, colour parameters and antioxidant activity were compared with those provided by potassium sorbate. In general, the variables with the largest differences among different storage times were energy level, sucrose, glucose, palmitic acid (C6:0) and oleic acid (C18:1n9). On the other hand, L∗ (top), a∗ (top), b∗ (top), pH, capric acid (C10:0) and lauric acid (C12:0) showed the greatest variation according to cupcake formulation. The results observed indicate that the lemon balm extract rich in rosmarinic acid can provide advantageous functional properties to bakery products.