Growing consumer interest in healthy foods has led to an increased demand for bioactive compounds derived from eco-technologies. This review highlighted two emerging technologies, pressurized liquid extraction (PLE) and supercritical fluid extraction (SFE), which are based on clean processes aimed at recovering bioactive compounds from different food sources. We studied how the different processing conditions provide many advantages and a great opportunity to obtain compounds with antioxidant, antibacterial, antiviral, or antifungal activity from plant matrices and industrial biowaste, especially antioxidant compounds (anthocyanins and polyphenols) due to their important role in health promotion. Our research was conducted through a systematic search in different scientific databases related to the PLE and SFE topics. The review analyzed the optimal extraction conditions using these technologies, which lead to the efficient extraction of bioactive compounds, the use of different equipment, and recent combinations of SFE and PLE with other emerging technologies. This has given rise to the development of new technological innovations, new commercial applications, and the detailed recovery of various bioactive compounds extracted from different plant and marine life food matrices. These two environmentally friendly methodologies are fully valid and have great future application prospects in biowaste valorization. They represent a feasible technological tool that can promote the implementation of a circular economy model for the food industry. The underlying mechanisms of these techniques were discussed in detail and supported by current literature.

This study aimed to valorize pomegranate by-products (peel and carpelar membranes—PPCM) through their high biological potential for phenolic compounds recovery. The influence of lower temperatures (40 and 60 °C) and pressures (20, 40, 60, 80, and 100 bar) than those generally used in pressurized liquid extraction (PLE) was evaluated through global extraction yield (X₀), and qualitative and quantitative composition of the phenolic compounds. Chromatographic techniques were used to analyze the two treatments with the highest X₀. Temperature, pressure, and their interaction had a significant influence on X₀. The best phenolic compounds extraction conditions were using pressurized ethanol at 60 °C and 40 bar (extract 1—E1, 37% on d.b.) and 60 °C and 80 bar (extract 2—E2, 45% on d.b.). Nevertheless, E1 presented a significantly higher content of α, β punicalagin, and ellagic acid (48 ± 2, 146 ± 11, and 25.6 ± 0.3 mg/100 g, respectively) than E2 (40 ± 2, 126 ± 4, and 22.7 ± 0.3 mg/100 g). Therefore, this study could validate the use of low pressures and temperatures in PLE to recover phenolic compounds from pomegranate residues, making this process more competitive and sustainable for the pomegranate industry.

Walnut milk residues (WMR) were investigated for the first time through their phenolic characterization including soluble (free, esterified, and etherified) phenolics and those released from their insoluble-bound form (insoluble-bound phenolic hydrolysates, IBPHs) and their antioxidant properties. Free phenolics were recovered and alkaline or acid hydrolysis were used to recover the remaining phenolic fractions. Total phenolic compounds (TPCs) and their antioxidant activity were analyzed by Folin–Ciocalteu, FRAP, and ORAC methods, respectively. Soluble phenolics (free + esterified + etherified fractions) showed a higher TPC (275.3 mg GAE 100 g⁻¹ dw) and antioxidant activity (FRAP: 138.13 µmol TE g⁻¹ dw; ORAC: 45.41 µmol TE g⁻¹ dw) with respect to the IBPH. There was a significant correlation between TPC and FRAP and ORAC values regardless of the fraction and tested sample. Phenolic acids and flavonoids were identified and quantified by ultra-performance liquid chromatography–electrospray tandem mass spectrometry (UPLC-ESI-MS/MS). Gallic acid, mainly in the free form (3061.0 µg 100 g⁻¹), was the most representative, followed by biochanin A, identified for the first time in a walnut product and mostly present in the fraction released from the esterified form (593.75 µg 100 g⁻¹). No detrimental cytotoxic impact on Caco-2 cells was observed. Hence, WMR could be considered a potential source for the development of nutraceutical and/or antioxidant food additives.

Germination is known to modify the bioavailability of nutrients and enhance the antioxidant potential of grains. In this research, pita bread made from germinated grains (GGB) was compared to non-germinated (NGB) counterparts to assess changes in nutritional profile, antioxidant capacity, and phenolic compound levels. Physical properties such as crumb porosity, dough density, and oil and water retention capacities were also evaluated to understand the influence of germination on bread texture and structure. Sensory evaluation panel assessed consumer acceptance, flavor, texture, and aroma. No significant differences were observed between GGB and NGB in most physical and nutritional attributes, except for a higher oil retention capacity in NGB. Germination influenced lipid absorption without affecting dough density or water absorption. Both GGB and NGB exhibited significantly greater antioxidant capacity compared to commercial bread (CB), with notable bioactive compounds, such as p-tyrosol and vanillic acid, present in GGB and NGB but absent in CB. Sensory evaluations indicated that bread made with sprouted grains offers similar acceptability to commercial bread, with enhanced flavor and texture that may improve consumer appeal. According to JAR analysis, attributes like crumb porosity and acid flavor were critical to GGB’s acceptability, while adjustments in the brown color of NGB could further improve its appeal. These findings suggest that germinated grains enhance bread’s nutritional and antioxidant qualities without compromising baking performance and may improve sensory attributes, making them a promising addition to multigrain bread formulations.