Orange and coffee grounds by-products, rich in phenolic bioactive compounds, can be used in the food industry as antioxidants, colorants, flavorings and additives, mainly because they are solvents that are easy to prepare, have a lower cost, are thermally stable, biodegradable, renewable, and are considered GRAS (Generally Recognized as Safe). Deep eutectic solvents, which are sustainable and have lower melting points, are effective for extracting these compounds. This study aimed to evaluate the use of deep eutectic solvents (DES) in extracting Total Phenolic Compounds (TPC), from orange by-products and spent coffee grounds. DES formed by citric acid: mannitol (CM-DES), and lactic acid: glucose (LG-DES), were evaluated by varying the following parameters: water content (10–50%), solid–liquid ratio (1:5–1:50 w/w) and temperature (40–50 °C). DES citric acid: mannitol presented the best efficiency in the extraction of TPC under the conditions of 10% water, 80 °C, and solid–liquid ratio 1:10 (w/w) for the orange by-products (1782.92 ± 4.50 mg GAE/L) and 1:15 (w/w) for spent coffee grounds (1620.71 ± 3.72 mg GAE/L). The highest antioxidant activity was observed in the extraction with CM-DES for both by-products in the three methods evaluated: Ferric Reducing Antioxidant Power (FRAP) (1.087 ± 0.004 and 1.071 ± 0.006 mol ascorbic acid/L), DPPH radical scavenging activity (2,2-difenil-1-picrilhidrazil—DPPH) (0.233 ± 0.003 and 0.234 ± 0.001 mol Trolox equivalent/L), and radical cation scavenging activity ABTS (2,2-azino-bis (3-ethyl-benzothiazoline-6-sulfonic acid—ABTS) (0.284 ± 7.16 and 0.319 ± 0.002 mol Trolox equivalent/L). Therefore, DES with citric acid: mannitol is a promising alternative to conventional solvents to recover phenolic compounds in agro-industrial by-products, such as orange by-products and SCG.

Thermosonication is a technique that combines ultrasound with mild temperatures and can be applied as an alternative to thermal pasteurization. This study aimed to evaluate the synergistic effect of thermosonication (Termo) on bioactive compounds (total anthocyanins concentration and total phenolic compounds), antioxidant activity and physicochemical characteristics of blackberry juice in comparison with conventional heat treatment (TT). The experiment was conducted based on the Central Composite Rotational Design, varying the amplitude (60% and 90%), temperature (64 °C and 86 °C) and time (114 s and 517 s) factors. The results showed that the amplitude and temperature factors significantly influenced (p < 0.05) the content of bioactive compounds studied, as well as the antioxidant activity and physicochemical properties, showing that the thermosonication treatment using 60% ultrasonic amplitude and 86 °C temperature provided more excellent retention and less degradation in the content of anthocyanins, phenolic compounds, antioxidant activity, and physicochemical properties (pH, acidity, total soluble solids and colour) of blackberry juice. Higher ultrasonic amplitude (90%) promoted changes in the physicochemical properties and degradation of the bioactive compounds studied and antioxidant activity. However, the limitations of this study are related to the specific matrix used, the seasonality of these fruits, the availability of raw material for processing and the limitation of large-scale ultrasonic equipment. These factors limit the expansion of these findings to other products. Overall, thermosonication can be considered a promising technique. Still, for its implementation as a possible alternative to conventional thermal methods, further studies are needed to investigate the stability of bioactive compounds and antioxidant activity of blackberry juice better.

Sargassum filipendula is a marine macroalgae, also known as brown algae. These species contain significant amounts of polysaccharides, such as alginates, and phenolic compounds, including phlorotannins, with excellent biological properties. This study evaluated the extraction of bioactive compounds from the residual biomass of Sargassum filipendula using deep eutectic solvents based on alkanol amines combined with polyols. The residual biomass presented a content of 7.36% protein, 1.11% lipids, 20.51% ash, 14.88% moisture, 50.25% total fibers, and 5.89% alginate. Preliminary screening identified N, N-(dimethylamino)-ethanol: benzyl alcohol (1.30:1) and N, N-(dimethylamino)-ethanol:1,3-propanediol (1.83:1) as the most efficient solvents for the extraction of bioactive compounds. The optimization process showed that the temperature and solid–liquid ratio significantly influenced (p < 0.05) the extraction of total phenolic compounds, phlorotannins, and the content of photosynthetic pigments. Intermediate temperatures (74.4 °C for N, N-(dimethylamino)-ethanol: benzyl alcohol (1.30:1) and 68.4 °C for N, N-(dimethylamino)-ethanol:1,3-propanediol (1.83:1), and a lower solid-to-liquid ratio (0.03) were optimal conditions to extract the low-pigment phlorotannins selectively. In contrast, higher temperatures (120 °C) maximized the extraction of phlorotannins and photosynthetic pigments. N, N-(dimethylamino)-ethanol: benzyl alcohol (1.30) extracted 110.64 mg PGE/g phlorotannins and 78.15 mg GAE/g phenolics, while N, N-(dimethylamino)-ethanol:1,3-propanediol (1.83:1) produced 21.57 mg PGE/g and 72.89 mg GAE/g, respectively. The extraction of photosynthetic pigments reached a maximum yield at 120 °C, using N, N-(dimethylamino)-ethanol: benzyl alcohol (1.30:1), with a content of 21.61 µg/g of chlorophylls and 38.11 µg/g of pheophytins, while N, N-(dimethylamino)-ethanol: 1,3-propanediol (1.83:1) provided content of 17.76 µg/g and 36.32 µg/g, respectively. The extracts exhibited antioxidant activity with 0.69 mg TE/mL in scavenging DPPH radicals, 24.42 mg TE/mL in scavenging ABTS radicals, and 2.26 mg TE/mL of iron-reducing antioxidant power. These results demonstrate the potential of DESs for the sustainable recovery of bioactive compounds from Sargassum filipendula residual biomass.

Purple grape juice produces a significant amount of grape pomace (GP) as a by-product, which can be reused as a raw material in producing craft beers with bioactive properties. The objective of this study was to produce craft beers with the addition of GP during the fermentation process to evaluate the incorporation of bioactive compounds, aiming at using a by-product generated in the production of grape juice. Craft beer was produced, incorporating GP at concentrations of 1%, 5%, and 10% (w/w), and the physicochemical, technological, bioactive, and sensory properties were evaluated. The beers with the highest concentrations of GP (10% w/w) exhibited higher bioactive concentrations, including phenolic compounds (308 mg GAE/L), flavonoids (0.05 g of quercetin/L), anthocyanins (754.6 mg cyanidin-3-glucoside/L), and antioxidant capacities, as measured by DPPH (1878.2 µM Trolox/L), ABTS (4294.5 µM Trolox/L), and FRAP (844.7 mg ascorbic acid/L) methods. Adding GP promoted lower brightness (62.2) and intensified the a*, b*, and chroma parameters (18.0, 10.1, and 20.6, respectively), with the pigments of GP contributing to changes in the color parameters. However, increased sedimentation was observed under both conditions analyzed (4 °C and 25 °C), due to the higher presence of particulate matter from GP (3.4% and 3.7%, respectively). In general, for sensory analysis, while the knowledge of beneficial effects did not significantly change emotional responses, there were distinct emotional profiles associated with different beer samples. Utilizing GP for the bioactivation of beer is a positive approach to enhance its overall properties and an effective way to address issues related to the disposal of this by-product.

Yeast biomass, a by-product of various industrial processes, is a sustainable source of food ingredients. Despite its nutritional richness, studies on Yarrowia lipolytica W29 biomass for high-value compound production using low-cost substrates like glycerol and glucose remain limited. These substrates enhance productivity and modulate cell wall composition. Extracting these compounds is complex but can be optimized through sequential hydrolysis, including autolysis and acid hydrolysis. In this study, mannoprotein exhibited a 60% emulsification index, 40 mN m⁻¹ surface tension for both substrates, and thermal stability with a mass retention above 30%. Acid hydrolysis yielded bioactive peptides (<1 kDa) with the highest antioxidant activity: 220 µM Trolox (ABTS), 270 µM Trolox (DPPH), and 125 µM ascorbic acid (FRAP). The raw biomass and feed ingredient (dry residue) provided 100% and 90% of the daily protein intake, respectively, with a β-glucan content of 17%. Glycerol and glucose resulted in similar high-value compounds, highlighting glycerol as a cost-effective carbon source. Thus, sequential hydrolysis is an effective strategy for extracting compounds from Y. lipolytica W29 biomass, offering a promising alternative for industrial applications due to its high nutritional value and functional properties.