The growing interest in prebiotic ingredients has led to the valorization of agri-food by-products, such as coffee silverskin, known for its richness in dietary fiber and health-promoting compounds. This study evaluated the impact of in vitro simulation of gastrointestinal digestion on the chemical composition (carbohydrates, caffeine, and chlorogenic acids) and prebiotic potential (probiotic growth, organic acid production, pH, and antioxidant activity) of milled coffee silverskin. The results show stability of polysaccharides during digestion, while caffeine and 5-caffeoylquinic acid were partially released into the bioaccessible fraction. The incubation of digested sample (DS) and the control (CS) with Lacticaseibacillus paracasei subsp. paracasei and Lactiplantibacillus plantarum subsp. plantarum resulted in probiotic growth, an increase in acetic acid production, and pH decrease. Following incubation, the cell-free supernatants of the DS and CS exhibited greater antioxidant activity compared to the negative control, glucose, and fructooligosaccharides. This study shows the functional potential of the whole silverskin due to its prebiotic and antioxidant properties.

Olive pomace (OLP) and stones (OLS) are key by-products of olive oil production, rich in lignocellulose and pectin, making them viable substrates for prebiotic oligosaccharide (OS) production. This study evaluated the chemical composition of OLP and OLS powders (OLPp and OLSp) and their potential for OS production through one-step fermentation using recombinant Bacillus subtilis 3610. Both substrates had comparable xylan and pectin levels, but OLSp showed greater potential, achieving a maximum total sugar yield of 60 ± 3 mg.g-1 after 12 h under optimal conditions (20 g.L-1 OLSp, pH 7.0, 45 °C). The resulting OS mixture from OLSp was predominantly composed of pectic oligosaccharides (72.1 %mol) and glucurono-xylooligosaccharides (11.6 %mol). This innovative process, competitive with commercial enzymes, highlights the potential of by-product valorisation for producing value-added food compounds. The findings provide insights into low-cost bioprocesses and underscore the importance of sustainable approaches in the industry of functional food ingredients.

Marine environments are the warehouse of a variety of novel bioactive compounds prone to be explored by food and feed industry. The growing interest in sulphated polysaccharides has led to the search for new sustainable sources, such as seawater. These compounds are naturally concentrated in salt pan brine water due to their evaporation by wind and sunlight. To take advantage of these sources, sulphated polysaccharides were concentrated from salt pan brine water using a scalable membrane ultrafiltration system with 30 and 100 kDa cut-off. This process allowed to concentrate ten times the polymeric material of brine water into 1.9 g/L, rendering a fluffy polysaccharide rich material after drying. It was mainly composed of 23 % (w/w) of uronic acids, 19 % of sulphate esters, and 34 % (w/w) of neutral sugars. This polymeric material has shown to stimulate in vitro both human macrophages and Atlantic salmon head kidney SHK-1 cells in a range of 6.25-50 μg/mL without toxicity, showing potential to be used in both human food and aquaculture feeding.

The environmental burden of plastic pollution has driven the search for sustainable alternatives, such as biodegradable bioplastics derived from agrifood byproducts, which hold the potential for addressing global waste management challenges. Given the close relationship between the biodegradability of biopolymers and soil microbial activities, it is vital to understand how the presence of novel bioplastics affects their function and structure. This study assessed microbial responses to different plastics: potato starch-based bioplastic, locust bean-based bioplastic, and non-biodegradable polyamide-polyethylene plastic in natural sandy-loam soil (LUFA 2.2). Soil without any (bio)plastics was used as a control. Despite initial pronounced differences in defragmentation rates between the two types of bioplastics, only 10 and 20 % w/w of the fragments were recovered after 17 weeks. The type of bioplastic influenced the fungal colonization pattern, with potato starch-based bioplastic resulting in more isolated fungal species than locust bean-based bioplastic. The soil dehydrogenase response was inconsistent, while (3-glucosidase activity showed an initial increase in both bioplastic treatments, with a sustained stimulation only in potato starch-based bioplastic. (3-glucosidase activity coincided with higher carbon substrate consumption maintained by the end of the 17 weeks of exposure, indicating more dynamic changes in microbial functions in potato starch-based bioplastic. Decreased carbon substrate consumption was observed in non-biodegradable polyamide-polyethylene plastic. The current study represents a first screening approach for the impact of applying agrifood byproducts as novel biopolymers directly in the soil, demonstrating their distinct effects without any pronounced adverse effects on soil microbiota compared to conventional polyamide-polyethylene plastic.

This study aims to structurally characterize a polysaccharide extracted from Cenostigma nordestinum gum (AGCn) and evaluate its prebiotic potential in human gut microbiota. AGCn, obtained by dissolution in water and precipitation in 70 % ethanol, was primarily composed of carbohydrates (93.61 %), with a low protein content (1.70 %) and some phenolic compounds (9.16 % Gallic Acid Equivalents). Its molecular weight was 6.19 × 104 g/mol, with a dispersity of 1.33. The main monosaccharides identified were arabinose (38 mol%) and galactose (31 mol%). Methylation analysis and 2D NMR spectra showed that the gum exuded from C. nordestinum is a branched arabinogalactan composed of →6)-β-Galp-(1→, →3,6)-β-Galp-(1→, and →3,4,6)-β-Galp-(1→ residues, containing chains of →3)-α-Araf-(1→ and →5)-α-Araf-(1→, with α-Araf-(1→ and α-Rhap-(1→ as terminal residues. The identification of →4)-α-GalpA-(1→ showed also the presence of a pectic polysaccharide. AGCn was metabolized by Lactobacillus brevis, Lactobacillus plantarum, and Lactobacillus casei probiotic bacteria. AGCn in vitro fermentation increased the ratio of Bifidobacterium and Bacteroides in the microbiota, decreased the abundance of bacteria associated with intestinal disease, and produced short-chain fatty acids. Thus, AGCn is an arabinogalactan with prebiotic potential as a gut microbiota modulator, offering significant value for future food and biotechnological applications.

This study presents a characterization of exopolysaccharide (EPS)-producing Streptococcus thermophilus strains isolated from goat milk, including information about structural and functional characteristics of EPS. The isolates exhibited efficient lactose fermentation, broad carbohydrate utilization, and desirable enzymatic activities for technological applications, particularly aminopeptidases and acid phosphatase, while lacking harmful enzymes and virulence traits. Among the four strains studied, GM4 emerged as a particularly promising probiotic due to its sensitivity to all tested antibiotics, high β-galactosidase activity (56.2 × 103 Miller units), moderate antioxidant capacity (scavenging 22.7% of DPPH and 5.7% hydroxyl radicals), cholesterol-lowering ability (26.9%), high auto-aggregation capacity (46.8%), and co-aggregation (>30%) with key foodborne pathogens including Escherichia coli, Listeria monocytogenes, and Staphylococcus aureus. GM4 produced an EPS with high dextranase resistance, and its production was enhanced in lactose-enriched media (yield = 2.58 g/L). The purified EPS consisted of two heteropolysaccharides (12.0 kDa and 112 kDa), primarily composed of glucose (Glc, 53%) and mannose (Man, 29%), with minor contributions from uronic acids (8%), ribose (6%), arabinose (2%), and galactose (2%). Key glycosidic linkages included (1→4)-Glc, (1→2,6)-Man, (1→2)-Man, and (1→4,6)-Glc. Functional assays demonstrated notable antioxidant activity, with 52.5% DPPH and 12.9% hydroxyl radical scavenging at 3 mg/mL EPS. These findings highlight S. thermophilus GM4 as a safe, technological, and functional candidate for dairy and probiotic applications, with its EPS exhibiting properties suitable for functional food incorporation.

The upcycling of food waste into high-value materials presents a key opportunity for sustainable waste management. While onion peel (OP) extracts have been investigated as additives for bioplastics, this study explores the direct incorporation of whole powdered OP (5-20 wt%) into starch-based films, eliminating extraction steps and fully valorizing this agro-industrial by-product. Using starch recovered from potato processing slurries as the polymeric matrix, the influence of OP on film structure, mechanical performance, water resistance, gas permeability, and antioxidant activity was evaluated. Chemical analysis of OP revealed a composition of 47% alcohol insoluble compounds (mainly pectin and cellulose), 12% alcohol soluble matter (primarily glucose-based carbohydrates), 6% lipids, 2%proteins, 5% gallic acid equivalents, and 27% ashes. The direct incorporation of powdered OP resulted in natural pigmentation, producing transparent films with an orangish hue. This approach enhances the aesthetic properties of films while eliminating the need for artificial dyes, contributing to a more sustainable product design. The developed bioplastics exhibited enhanced mechanical properties and improved water resistance, making them attractive for sustainable packaging applications. At OP concentrations above 10 wt%, Young's modulus increased from 1214 MPa to 1496 MPa, while tensile strength and elongation at break decreased from 31.4 MPa to 24.6 MPa and from 4.5% to 2.1%, respectively. Water contact angles increased from 75° up to 87°, and water vapor permeability was reduced by up to 60%, improving moisture resistance. Importantly, OP incorporation did not compromise oxygen (O2), carbon dioxide (CO2), or nitrogen (N2) barrier properties and imparted significant antioxidant activity, with 20 wt% OP-based films inhibiting 93% of the 2.2'-azinobis-(3-ethylbenzothiazoline-6-sulfonic) acid radical cation (ABTS.+) after 6 h. This study presents an innovative waste-to-resource strategy that eliminates processing waste, aligns with circular economy principles, and demonstrates the first use of whole OP as a multifunctional additive in starch-based bioplastics. By replacing conventional extraction-based approaches, this method enhances material sustainability while promoting a scalable, zero-waste approach to packaging development.

Cyanobacterial extracellular polymeric substances (EPS), mainly composed by heteropolysaccharides, can be attached to the cell wall (CPS) or released to the environment (RPS). These polymers have an unusually highly diversified monosaccharidic composition, making them attractive for biotechnological/biomedical applications. However, their production is still poorly understood hindering their optimisation for industrial needs. This work aimed at better understanding the biosynthesis of the 6-deoxysugars fucose and rhamnose in the model cyanobacterium Synechocystis sp. PCC 6803. To that end, genes encoding proteins putatively involved in the biosynthesis of GDP-L-fucose [ sll1213 ( fucS )] and dTDP-L-rhamnose [ slr0985 ( rfbC1 ) and slr1933 ( rfbC2 )] were deleted. As previously observed, Δ fucS had significant growth impairment and its RPS did not contain any fucose or rhamnose. Here, we also showed that both deoxyhexoses’ pathways are completely impaired in Δ fucS . In contrast, both Δ rfbC1 and Δ rfbC1 Δ rfbC2 although producing significantly less RPS and more CPS than the wild type, did not show major differences regarding the RPS monosaccharidic composition. These results strongly suggest that their gene products are not essential for rhamnose biosynthesis. Transcriptional analysis revealed that one of the gmd genes ( slr1072 ), putatively encoding a GDP-mannose 4,6-dehydratase, was upregulated in all the knockout strains, and that the three EPS-related genes in the same operon as rfbC1 ( slr0982 , slr0983 and slr1610 ) were upregulated in both Δ rfbC strains. Altogether, our results reveal that rhamnose biosynthesis in Synechocystis depends on FucS but not on the putative RfbC enzymes, underlining the need to further elucidate the mechanisms involved in the biosynthesis of this deoxyhexose.

This study elucidates the structural state of pectic polysaccharides within litchi cell walls and explores the self-assembly gelation behaviour of arabinan enriched litchi pectic polysaccharides using small and large amplitude oscillation shear methods (SAOS/LAOS). Water- (WLP), chelating agent- (CALP), sodium carbonate- (SCLP), and sodium hydroxide-soluble (SHLP) pectic polysaccharides were sequentially extracted from litchi pulp cell walls. SCLP was the fraction with the highest extracted yield (26.4%), composed by low-methoxyl pectic polysaccharides rich in neutral sugars (RG-I). SCLP demonstrated a propensity for self-assembled gel formation, as evidenced by its multi-branched structures and locally amorphous aggregates observed in AFM images. SCLP gels exhibit pseudoplastic fluid behaviour in steady shear tests, and their viscosity was dependent on concentration but not significantly affected by temperature (4-80 degrees C). Dynamic rheological measurement (SAOS) highlighted SCLP's exhibited solid-like viscoelastic behaviour (G ' > G ''), with enhanced gel strength at high concentrations. Thixotropic properties of SCLP gels increased with concentration. The temperature sweep demonstrated that the rheological behaviour of SCLP is thermally reversible. In LAOS, Lissajous curves revealed significant strain stiffening and shear thinning trends of SCLP gels, with elevated third harmonic intensity (I3/I1) correlating with the nonlinear behaviour. The occurrence of secondary loop indicates the enhanced the gel restructuring capacity at high concentration, likely due to the crosslink density provided by long arabinose side chains in SCLP. Cryogenic-scanning electron microscopy further confirmed a more regular interlinked network in high-concentration SCLP gels. These findings offer critical insights into the optimization of self-assembled pectic polysaccharide gels for use as gelling agents and thickeners in complex, real-world systems, including food.

The development of multifunctional materials from agrifood residues supports circular bioeconomy strategies by reducing waste and promoting renewable feedstocks. This study investigates rejected rice dust (RD) and colored rice (CR), two starch‐rich rice processing by‐products, as alternative sources for natural starch‐based bioplastics, using purified rice starch (PRS) as a benchmark. RD and CR contained 79.9% and 82.9% total carbohydrates (48.6% and 51.8% starch), versus 98.3% carbohydrates and 70.2% starch in PRS. CR exhibited the highest amylose (29.5%) and phenolic content (20.9 mg GAE/100 g), compared to RD (21.3%; 8.8 mg GAE/100 g) and PRS (15.8%; 2.3 mg GAE/100 g). Gelatinization peak temperatures are elevated in RD (74.2°C) and CR (73.9°C) versus PRS (66.7°C). RD‐based films showed mechanical strength (5.4 MPa) and modulus (146 MPa) comparable to PRS (5.5 MPa; 175 MPa), while CR‐based films have lower modulus (53 MPa) but greater elongation at break (20.2%). Contact angles are highest in CR (119°), followed by PRS (102°) and RD (70°). Antioxidant activity reached 88% (CR), 33% (RD), and 10% (PRS). Only CR‐based films provided UV‐B protection. These results highlight RD and CR as renewable matrices for producing environmentally sustainable, functionally enhanced starch‐based materials for packaging and coating applications.

Diatoms have garnered attention as sources of natural bioactive compounds, making them attractive for developing high-value products for different biotechnological ends, particularly for nutritional applications. Despite their potential, the chemical composition of industrially produced biomass remains largely underexplored. In this context, this study was focused on a thorough characterisation of the biochemical profile of three marine diatom species produced outdoors in photobioreactors: Chaetoceros calcitrans, Cylindrotheca fusiformis, and Nannofrustulum shiloi. The proximal composition of biomasses accounted for 29-35 % ashes, 21-30 % proteins, 7-14 % lipids, 3-7 % carbohydrates, and 0.4-2 % pigments. Each species contained >35 % of essential amino acids, mainly alanine and leucine. Distinct soluble protein and peptide size distribution patterns were observed among the three species. Galactose (26-45 mol%), uronic acids (20-29 mol%), and glucose (3-21 mol%) were the main sugar residues found in all species. Galactose was mainly derived from floridoside and related compounds. The most abundant fatty acid was 20:5 n-3 in C. calcitrans (18 %), whereas in C. fusiformis was 16:1 n-7 (20 %) and 16:0 in N. shiloi (21 %). Lipidomics revealed 325 species of glycolipids, phospholipids, betaine lipids, sphingolipids, fatty amides, and sterol lipids, also with a distinct distribution along the lipid classes. C. calcitrans was the richest in chlorophylls (14 mg.g(-1)) and carotenoids (8 mg.g(-1)). In mineral analysis, calcium showed the highest difference, 66 mg.g(-1) in N. shiloi, 27 mg.g(-1) in C. fusiformis, and 4 mg.g(-1) in C. calcitrans. Overall, this study highlights the nutritional potential of industrially produced diatoms, with distinct chemical profile that can be explored for target applications.

Cordia africana fruit contains a mucilaginous pulp rich in hydrocolloid with nutraceutical potential, whose composition and bioactive potential remain uncertain. This study evaluated its structural characterization, toxicity and ability to prevent DSS-induced ulcerative colitis in mice. The hydrocolloid was extracted with hot water and precipitated with ethanol (1:3 v/v), yielding 7.2 % (w/w). The extracted hydrocolloid was administered for 15 days to study its preventive effect on ulcerative colitis, which was subsequently induced by the administration of DSS (3 %) in drinking water. The hydrocolloid (65 kDa) was composed mainly of negatively charged polysaccharides (glucans and uronic acids) with a high degree of esterified phenolic acids, preventing their degradation during digestion (6.6 +/- 0.5 and 13.2 +/- 0.5 mg GAE/g free and bound, respectively, including syringic, hydroxybenzoic, and dihydrocaffeic acids). At a dose of 2000 mg/kg, the hydrocolloid did not induce systemic toxic effects in vivo and alleviated DSS-induced colitis, reducing clinical symptoms such as colon inflammation. These effects were associated with lower disease activity indices, increased colon length, enhanced myeloperoxidase and eosinophil peroxidase activity, as well as preservation of microvilli and a reduction of inflammatory infiltrate (with a pretreatment dose of 100 mg/kg hydrocolloid). The hydrocolloid has potential as a prebiotic, as it increased the proliferation of probiotic Lactobacillus and Bifidobacterium and reduced Acetobacteraceae and stimulated short-chain fatty acids synthesis in the gut microbiota of mice subjected to colitis. These findings highlight C. africana hydrocolloid's potential as a functional ingredient with prebiotic and anti-inflammatory properties for maintaining colon health.

Prebiotic demand is increasing due to growing concerns about human gut health and well-being. Recently, agri-food by-products have been explored as a potential source of prebiotic ingredients. This study analysed the chemical composition of a freeze-dried coffee silverskin extract (FSE) and evaluated its impact on Lacticaseibacillus paracasei subsp. paracasei BAA-52 ATCC growth. The FSE was obtained by multi-frequency multimode modulation ultrasonic vibration. Soluble dietary fiber accounted for 15.2 % of the extract, being mainly composed of uronic acids (58 mol%) and glucose (13.4 mol%). HPLC-DAD-MS-ESI+ and HPLD-DAD analyses revealed a phenolic-rich composition (mainly caffeoylquinic acids), as well as the presence of caffeine, and 5-hydroxymethylfurfural. The probiotic was incubated in De Man, Rogosa, and Sharpe broth supplemented with different concentrations of the FSE (1–4 %, w/v). The 2 % and 4 % (w/v) concentrations significantly enhanced L. paracasei subs. paracasei growth and decreased the pH of the medium, indicating its potential as a prebiotic ingredient.

Yeast cell walls undergo modifications during the brewing process, leading to a remodelling of their architecture. One significant change is the increased insolubility of the cell wall glycogen pool, likely due to the formation covalent bonds between glycogen and cell wall polysaccharides. To verify this hypothesis, we extracted the brewer's spent yeast with 4 M KOH, obtaining an insoluble glucan fraction (AE.4 M) primarily composed of (a1-* 4)-and (1-* 3)-linked Glc residues. Dynamic nuclear polarization solid-state NMR of AE.4 M revealed distinct glucan resonances that helped to differentiate between a-and fi glucosyl (1-* 4)-linked residues, and confirm covalent linkages between (fi1-* 3)-glucans and glycogen through a (fi1-* 4)-linkage. The hydrolysis with different endo-glucanases (zymolyase, cellulase, and lichenase) was used to obtain solu-bilized high molecular weight glycogen fractions. NMR analysis showed that covalent links between glycogen and (fi1-* 6)-glucans through (a1-* 6) glycosidic linkage, with branching at the C6 position involving (fi1-* and (fi1-* 6)-glucans. HPAEC-PAD analysis of the enzymatically released oligosaccharides confirmed covalent linkages of (fi1-* 3), (fi1-* 6)-, and (fi1-* 4)-glucan motifs with (a1-* 4)-glucans. This combination of multiple enzymatic approaches and NMR methods shed light into the role of yeast cell wall glycogen as a structural core covalently linked to other cell wall components during the brewing process.

The influence of locust bean gum (LBG) galactomannans (GMs) molecular weight (Mw) to assemble microparticulate systems was evaluated, and carriers for deep lung delivery were developed. A commercial batch of LBG with a mannose/galactose (M/G) ratio of 2.4 (batch 1) was used to study the influence of different microwave partial acid hydrolysis conditions on carbohydrate composition, glycosidic linkages, and aqueous solutions viscosity. The microwave treatment did not affect the composition, presenting 4-Man (36-42 %), 4,6-Man (27-35 %), and T-Gal (24-25 %) as the main glycosidic linkages. Depolymerization led to a viscosity reduction (≤0.005 Pa·s) with no major impact on polysaccharide debranching. The structural composition of the LBG galactomannans were further elucidated with sequence-specific proteins using carbohydrate microarray technologies. A second batch of LBG (M/G 3.3) was used to study the impact of GMs with different Mw on microparticle assembling, characteristics, and insulin release kinetics. The low-Mw GMs microparticles led to a faster release (20 min) than the higher-Mw (40 min) ones, impacting the release kinetics. All microparticles exhibited a safety profile to cells of the respiratory tract. However, only the higher-Mw GMs allowed the assembly of microparticles with sizes suitable for this type of administration.

Micro-nano encapsulation can be impactful in flavour masking of bioactives, and it has the potential to be used in the development of functional food ingredients.This work aimed to develop functional foods using emulsified resveratrol, assessing the impact of resveratrol addition and its consumer acceptance. Resveratrol-loaded emulsions were produced through high-speed homogenization/ultrasonication. Functional snacks (crackers and cookies) loading 4 mg resveratrol/g were developed using resveratrol-loaded emulsions and free resveratrol. Results showed that the incorporation of emulsified resveratrol in the dough led to an increase in its elasticity and a decrease in its consistency. Slight color differences were noticed between non-encapsulated resveratrol and reference samples. The texture of baked crackers and cookies showed a decrease in hardness for the emulsified cookies and an increase in the crackers.Sensory analysis was conducted with over one-hundred volunteers. For both products, the reference sample was the highest-rated sample in overall liking, followed by the emulsion-loaded sample and the unencapsulated resveratrol-loaded sample. Unencapsulated resveratrol-loaded and emulsion-loaded samples displayed an increase in bitterness when compared to the reference. The sensory analysis revealed a slight positive impact of the encapsulation of resveratrol versus the unencapsulated resveratrol. Nonetheless, further progress needs to be achieved to reduce resveratrol's impact.

Fatty foods are very susceptible to lipid oxidation caused by oxygen and light. To minimize this issue, active bioplastic materials are suitable for food packaging. In this work, the feasibility of blending locust bean milling derived dust (LBMD) with potato starch to develop heat-sealable bioplastic films for packaging sliced cheese and oat cookies was studied. Blending LBMD with starch allowed to obtain bioplastic films 2-fold more rigid (Young's modulus of ca. 48 MPa) and 1.3-fold more resistant to water (water contact angle of ca. 87 degrees) than LBMD-based films (Young's modulus of ca. 12 MPa and water contact angle of ca. 47 degrees), maintaining their UV protective capacity. LBMD/starch-based bioplastic films were used to pack cheese, with no molds or yeasts grown after 21 days, similar to petroleum-based plastic packages used as reference. Despite cheese dehydration (ca. 10% weight loss), its texture did not significantly change after the storage period. An increase (ca. 43%) in volatile com-pounds derived from cheese oxidation was observed after 7 days of storage. When used to pack oat cookies, LBMD/starch-based bioplastic films played an active role in decreasing oxidation-derived volatile compounds after 21 days of storage, maintaining their textural properties, when compared to oat cookies packaged with petroleum-based plastic. Therefore, blending LBMD with starch revealed to be a proper strategy to develop heat -sealable and active bioplastic films with water absorption, protection against UV radiation, volatile compounds scavenging capacity, and antioxidant activity suitable to preserve fatty foodstuffs while providing them new characteristics.

Phenolic compounds are responsible for food unpleasant taste properties, including astringency, due to their ability to interact with salivary proteins and oral constituents. Astringency is a crucial attribute for consumer's acceptability. To fulfill the demand for both healthy and tasty food, polysaccharides raise as a good alternative to modulate astringency. In this work, a cell-based quaternary system was developed to evaluate the ability of polysaccharides to reduce the interaction between two classes of hydrolysable tannins - gallotannins (tannic acid) and ellagitannins (punicalagin) - and oral constituents (cells, salivary proteins and mucosal pellicle). So, pectic polysaccharide fractions isolated from grape skins, imidazole soluble polysaccharides (ISP) and carbonate soluble polysaccharides (CSP), as well as a commercial pectin, were tested.Results showed that the polysaccharide's effect depends on the structural features of the molecules involved. CSP fraction and pectin were the most effective, reducing the interactions between both tannins and the oral constituents, mainly in the complete oral model. The highest uronic acid content and the presence of methyl esterified groups could explain their high reduction ability. For tannic acid, the reduction effect increased along with the galloylation degree, while the interaction of beta-punicalagin with the oral constituents was practically inhibited at 3.0 mg.mL(-1).

A Leuconostoc mesenteroides strain (SJC113) isolated from cheese curd was found to produce large amounts of a mucoid exopolysaccharide (EPS). An analysis revealed the glucan nature of the EPS with 84.5% (1→6)-linked α-d-glucose units and 5.6% (1,3→6)-linked α-d-glucose units as branching points. The EPS showed 52% dextranase resistance and a yield of 7.4 ± 0.9 g/L from MRS medium supplemented with 10% sucrose within 48 h. Ln. mesenteroides SJC113 was also characterized and tested for the production of EPS as a fat substitute in fresh cheese. Strain SJC113 showed high tolerance to a wide range of NaCl concentrations (2, 5 and 10%), high β-galactosidase activity (2368 ± 24 Miller units), cholesterol-reducing ability (14.8 ± 4.1%), free radical scavenging activity (11.7 ± 0.7%) and hydroxyl scavenging activity (15.7 ± 0.4%). The strain had no virulence genes and was sensitive to clinically important antibiotics such as ampicillin, tetracycline and chloramphenicol. Ln. mesenteroides SJC113 produced highly viscous EPS during storage at 8 °C in skim milk with 5% sucrose. Therefore, these conditions were used for EPS production in skim milk before incorporation into fresh cheese. Four types of fresh cheese were produced: full-fat cheese (FF) made from pasteurized whole milk, non-fat cheese (NF) made from pasteurized skim milk, non-fat cheese made from skim milk fermented with Ln. mesenteroides without added sugar (NFLn0) and non-fat cheese made from skim milk fermented with Ln. mesenteroides with 5% sucrose (NFLn5). While the NF cheeses had the highest viscosity and hardness, the NFLn5 cheeses showed lower firmness and viscosity, higher water-holding capacity and lower weight loss during storage. Overall, the NFLn5 cheeses had similar rheological properties to full-fat cheeses with a low degree of syneresis. It was thus shown that the glucan-type EPS produced by Ln. mesenteroides SJC113 can successfully replace fat without altering the texture of fresh cheese.

Gracilaria vermiculophylla has the potential to be used as a food ingredient due to its nutritional and bioactive values, however, the aroma is considered a restrictive factor for its large acceptance by consumers. In-depth knowledge about its volatile profile is crucial for the definition of mitigation strategies to overcome this drawback and to improve its acceptability. This work aims to characterize the volatile profile of G. vermiculophylla using an advanced multidimensional chromatographic technique. For the first time, G. vermiculophylla volatile profile was unveiled and a total of 136 volatile compounds were determined and grouped by 10 chemical families, including aldehydes, ketones, alcohols, mono and sesquiterpenic compounds, norisoprenoids, esters, lactones, carboxylic acids, and halogenated compounds. From these, monoterpenic compounds were present in higher number (31 out 136) and aldehydes exhibited the largest GC areas (17-27 % of the total). A G. vermiculophylla aroma wheel was developed by combining data from the list of the detected volatile components with the respective aroma descriptors available in the literature. This strategy allowed to identify the volatile compounds whose aroma descriptors may potentially explain ca. 70 % of the aroma notes present in the algal aroma wheel. This included undesired fishy and sulfuric notes from dimethyltrisulfide and herbaceous notes from fatty acid derivatives, as aldehydes, and positive citric notes linked to monoterpenic compounds. However, G. vermiculophylla volatile compounds related to sweet, almond, beany, fresh, and minty notes, not yet considered in the algal aroma wheel, were also determined. This information may be further used to define mitigation strategies of non-valued algae aromas through volatiles' insights, contributing to the future acceptance of algae food products.