Physicochemical Characterization and Evaluation of Gastrointestinal In Vitro Behavior of Alginate-Based Microbeads with Encapsulated Grape Pomace Extracts

Abstract

Grape pomace is a byproduct of wineries and a rich source of phenolic compounds that can exert multiple pharmacological effects when consumed and enter the intestine where they can then be absorbed. Phenolic compounds are susceptible to degradation and interaction with other food constituents during digestion, and encapsulation may be a useful technique for protecting phenolic bioactivity and controlling its release. Therefore, the behavior of phenolic-rich grape pomace extracts encapsulated by the ionic gelation method, using a natural coating (sodium alginate, gum arabic, gelatin, and chitosan), was observed during simulated digestion in vitro. The best encapsulation efficiency (69.27%) was obtained with alginate hydrogels. The physicochemical properties of the microbeads were influenced by the coatings used. Scanning electron microscopy showed that drying had the least effect on the surface area of the chitosan-coated microbeads. A structural analysis showed that the structure of the extract changed from crystalline to amorphous after encapsulation. The phenolic compounds were released from the microbeads by Fickian diffusion, which is best described by the Korsmeyer–Peppas model among the four models tested. The obtained results can be used as a predictive tool for the preparation of microbeads containing natural bioactive compounds that could be useful for the development of food supplements.

In Vitro Bioaccessibility Assessment of Phenolic Compounds from Encapsulated Grape Pomace Extract by Ionic Gelation

“…Total phenolic content (TPC), total flavonoid content (TFC), and total extractable proanthocyanidins (TPA) were determined spectrophotometrically according to Martinović et al [ 2 ]. The content of phenolic compounds was expressed as the mean of replicates ± standard deviation (SD).…”

“…According to method described by Martinović et al [ 2 ], determination of anthocyanins was performed. Briefly, two mobile phases were used: A. water/formic acid/acetonitrile (87:10:3, v/v/v ) and B. water/formic acid/acetonitrile (40:10:50, v/v/v ) with gradient program 10 min from 10 to 25% mobile phase B, 5 min from 25 to 31% mobile phase B, 5 min from 31 to 40% mobile phase B, 10 min from 40 to 50% mobile phase B, 10 min from 50 to 100% mobile phase B, and 10 min from 100 to 10% mobile phase B.…”

“…It consists of the skins, seeds, pulp, and sometimes the stems of the grapes, which influence its chemical composition, rich in many different components such as sugars, fibers, fats, proteins, bioactive phenolic compounds, etc. [ 1 , 2 , 3 ]. Scientific interest in phenolic compounds from grape pomace is most prominent in the literature and has not diminished over the years, as they offer numerous benefits when used in the pharmaceutical, food, and cosmetic industries, or in medicinal applications.…”

Porous Alginate Microcapsule-Containing Sweet Basil Oil (Ocimum basilicum) Generated by Gas Foaming with Ionic Gelation as an Efficient Antioxidant Delivery in Stimulated Poultry Gastrointestinal Tract

“…AG has been widely used for intestinal delivery due to the resistance to acidic gastric juice, allowing active ingredients release at target site . Previously, AG hydrogels loading total phenolic compound (TPC) from grape pomace extract showed a great encapsulation efficiency (%EE) …”

“…10 Previously, AG hydrogels loading total phenolic compound (TPC) from grape pomace extract showed a great encapsulation efficiency (%EE). 15 The porous structure, a material with high porosity and pore interconnectivities, has highly effective adsorption and high physical stability due to the high internal surface area. It has recently gained considerable attention for its potential in the drug delivery and food industry.…”