Application of Polyphenol-Loaded Nanoparticles in Food Industry.

Nanotechnology is an emerging field of science, and nanotechnological concepts have been intensively studied for potential applications in the food industry. Nanoparticles (with dimensions ranging from one to several hundred nanometers) have specific characteristics and better functionality, thanks to their size and other physicochemical properties. Polyphenols are recognized as active compounds that have several putative beneficial properties, including antioxidant, antimicrobial, and anticancer activity. However, the use of polyphenols as functional food ingredients faces numerous challenges, such as their poor stability, solubility, and bioavailability. These difficulties could be solved relatively easily by the application of encapsulation. The objective of this review is to present the most recent accomplishments in the usage of polyphenol-loaded nanoparticles in food science. Nanoparticles loaded with polyphenols and their applications as active ingredients for improving physicochemical and functional properties of food, or as components of active packaging materials, were critically reviewed. Potential adverse effects of polyphenol-loaded nanomaterials are also discussed.

In vitro digestion of meat- and cereal-based food matrix enriched with grape extracts: How are polyphenol composition, bioaccessibility and antioxidant activity affected?

The aim of this study was to evaluate the effect of enriching a complex food matrix (FM) with grape extracts on polyphenol content, composition, bioaccessibility and antioxidant activity during digestion. The grape extracts and FM were separately tested under the same conditions as controls. The FM by itself contains a significant amount of phenolic acids and flavonols, influencing the final recovery of polyphenols from grape extracts. The FM significantly increased the total recovery of polyphenols after digestion of grape seed extracts compared to those digested without the FM; however, a low recovery of proantocyanidins and total flavonoids was observed. Digestive fluids and FM compounds significantly increased the total polyphenol content of grape digests and significantly contributed to their ABTS+ scavenging activity and ferrous-ion-chelating capacity. The present study suggested that enrichment of meat- and cereal-based products with grape polyphenol extracts could be a good strategy to formulate a healthier diet.