Effect of high-pressure processing to improve the safety and quality of an Quercus acorn beverage

The development of an acorn beverage can be an opportunity to increase the intake of bioactive compounds and add value to Quercus acorn. However, unprocessed plant-based beverages have a very short shelf-life and thermal treatments affect their overall quality. High-pressure processing (HPP) emerges as a possible solution to better retain nutritional properties and sensorial quality and extend shelf-life. This research assessed the impact of HPP (450/600 MPa, 5/12.5/20 min) and thermal processing (TP, 85 °C, 30 min) on an acorn beverage during 63 days of refrigerated storage (4 °C). From all processing conditions, HPP at 450 MPa for 5 min showed to be suitable to assure microbiological safety (mesophiles, psychrophiles, yeasts and moulds, and Enterobacteriaceae) during 63 days and to better preserve total soluble solids and colour. The antioxidant activity (ABTS/DPPH) was similar to higher for heat-treated samples, being gallic acid the main phenolic compound found in the beverage. Total carbohydrates, lipids, proteins, minerals, and fatty acids contents were similar for HPP and TP. This beverage revealed low thrombogenicity and atherogenicity indices, and potassium as the main mineral. Concluding, HPP extended the shelf-life of the beverage and improved the physicochemical quality, revealed by panellists preference, as revealed by sensorial analysis.