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Commercial cocoa and hazelnut-based sweet spreads typically present a poor nutribiochemical level due to their ingredients and recipes, while nowadays, there is the need of developing sustainable food products addressing both an improved nutritional and environmental profile. The aim of this work was then to develop an innovative hazelnut/carob-based spread with potential high sustainability and nutritional profile, including the exploitation of grape-processing residues (grape skin flour and grapeseed oil) and carob pulp as cocoa surrogate. Rheological (rotational/oscillatory), oxidative, and thermal features of the spread were assessed and compared with two commercial nut-cocoa-based products. Tribology was used to mimic and evaluate the spreads' behavior during oral consumption, and sensory profile (by quantitative descriptive analysis) was also assessed. All products exhibited a pseudoplastic behavior, with the elastic component prevailing over the viscous one. The innovative product showed the highest lubricity from both rheological and sensory analysis, thus well correlating to the obtained lowest viscosity and friction factor trends. Grapeseed oil provided a better nutritional profile, but the largest amount of unsaturated fatty acids promoted oxidation, despite the higher total phenolic content and antioxidant capacity coming from the use of carob and grape skin powders. The sensory perception investigation revealed a characteristic mouthfeel/flavor for the new spread identified having a more fluid consistency and a bitter/sour taste, together with a greater stickiness and a poorer smoothness due to a higher fiber content and solid fat absence.

Polyphenols are multifaceted bioactive compounds, but little is known about their real impact on human health after consumption. In this work, the phenolic profiling of quebracho, yellow maize, and violet rice extracts was comprehensively investigated, together with the impact of in vitro digestion and colonic fermentation on the bioaccessibility and bioavailability of these phytochemicals. The different matrices showed distinct profiles, potentially influencing in vitro starch digestion under cooking conditions. Furthermore, after the extracts underwent in vitro gastrointestinal digestion and faecal fermentation, phenolics exhibited a differential bioaccessibility trend at every digestion level, with matrix-dependent behaviour. The bioavailability results suggest that polyphenols are metabolised during colonic fermentation, mainly into tyrosols, phenolic acids, and lignans, which are partially absorbed by Caco-2 cells. By combining metabolomics with in vitro cellular methods, this research provides new insights into the fate of these phytochemicals in the gut, yielding comprehensive data on their consumption in food matrices.

The health benefits of extra virgin olive oil (EVOO) are far proven. However, considering that this oil is consumed also cooked, this work aimed to evaluate the impact of different cooking techniques on human colorectal adenocarcinoma cells (Caco-2) exposed to in vitro digested EVOO. In particular, the effect of different cooking methods, namely sauteing, deep-frying, and Roner , was assayed and compared to a raw EVOO sample. The Caco-2 cell lysates were analyzed through an untargeted lipidomics approach, and multivariate statistics were used to identify the marker compounds of the differences in cells’ lipidomic signatures. Despite representing the cooking at the lowest temperature (but longer time), cells exposed to Roner cooked EVOO presented the most distinguished lipidomic profile. The markers of differences in Caco-2 could be related to oxidative stress-related compounds such as oxidized glutathione, diketogulonic acid, ceramides, and diglycerides. Taken together, our findings indicate that the differences in EVOO composition determined by cooking could impose significant lipidomic perturbation on the human intestinal cells.

Triticale-based biscuits were formulated with increasing substitution levels (i.e., 0, 25, 50, 75, and 100% w/w) of malted triticale flour (MTF). The products were analyzed for technological and nutritional characteristics, including the evaluation of the in vitro starch digestion. The results indicated that the substitution of triticale flour with MTF increased (p < 0.05) the total dietary fiber and ash contents. Total starch decreased (p < 0.05) when the level of MTF increased in the formulation, causing an increase in reducing sugars and an increase in the starch hydrolysis index and in the in vitro predicted glycemic index (pGI). The hardness and spread ratio values of biscuits decreased (p < 0.05) with increasing levels of MTF in the recipe. The lightness of doughs and biscuits decreased (p < 0.05) with increasing MTF levels. Overall, MTF could be used to formulate biscuits with higher dietary fiber content than native triticale flour and a medium to high in vitro glycemic index value as a function of the substitution level.

Wheat is a prevalent food worldwide, although its production arises several tonnes of industrial by-products that merit valorisation, owing to sustainable demands. In this work, an untargeted metabolomics approach was applied to shed light on the profile of free and bound phenolic compounds in white and wholegrain flours, as well as the major wheat by-products, namely wheat bran, wheat shorts and wheat middlings. By-products and wholegrain flours were found to be rich sources of ferulic acid derivatives, lignans, and alkylresorcinols, mostly bound to wheat fibre components, whereas different flavonoids were found in their free forms. Afterwards, the in vitro gastrointestinal digestion of these matrices showed that flour phenolics, in particular lignans, were more bioaccessible than those from wheat by-products. These results support the carrier effect attributed to dietary fibre and open a wide perspective on the use of underexploited wheat by-products to formulate novel functional foods.

Wheat flour is one of the most prevalent foodstuffs for human consumption, and novel strategies are underway to enhance its nutritional properties. This work evaluated wholegrain flours from bread wheat lines with different amylose/amylopectin ratios through in vitro starch digestion and large intestine fermentation. High-amylose flours presented a higher resistant starch content and lower starch hydrolysis index. Moreover, UHPLC-HRMS metabolomics was carried out to determine the profile of the resulting in vitro fermentates. The multivariate analysis highlighted distinctive profiles between the flours derived from the different lines compared to the wild type. Peptides, glycerophospholipids, polyphenols, and terpenoids were identified as the main markers of the discrimination. The high-amylose flour fermentates showed the richest bioactive profile, containing stilbenes, carotenoids, and saponins. Present findings pave the way toward applying high-amylose flours to design novel functional foods.

A multi-omics approach was adopted to investigate the impact of lactic acid fermentation and seed germination on the composition and physicochemical properties of rye doughs. Doughs were prepared with either native or germinated rye flour and fermented with Saccharomyces cerevisiae, combined or not with a sourdough starter including Limosilactobacillus fermentum, Weissella confusa and Weissella cibaria. LAB fermentation significantly increased total titrable acidity and dough rise regardless of the flour used. Targeted metagenomics revealed a strong impact of germination on the bacterial community profile of sprouted rye flour. Doughs made with germinated rye displayed higher levels of Latilactobacillus curvatus, while native rye doughs were associated with higher proportions of Lactoplantibacillus plantarum. The oligosaccharide profile of rye doughs indicated a lower carbohydrate content in native doughs as compared to the sprouted counterparts. Mixed fermentation promoted a consistent decrease in both monosaccharides and low-polymerization degree (PD)-oligosaccharides, but not in high-PD carbohydrates. Untargeted metabolomic analysis showed that native and germinated rye doughs differed in the relative abundance of phenolic compounds, terpenoids, and phospholipids. Sourdough fermentation promoted the accumulation of terpenoids, phenolic compounds and proteinogenic and non-proteinogenic amino acids. Present findings offer an integrated perspective on rye dough as a multi-constituent system and on cereal-sourced bioactive compounds potentially affecting the functional properties of derived food products.

Durum wheat spaghetti samples prepared with increasing levels of resistant starch (RS) from debranched waxy rice starch (DWRS; i.e., 0, 5, 10, 15 g/100 g w/w) were analyzed for chemical composition, quality and sensory parameters and in vitro starch digestion. All the DWRS-containing spaghetti was “high in fibre”, the dietary fiber content being > 6 g/100 g. In addition, spaghetti with the highest level of DWRS showed the highest RS content (p < 0.05), being 11.4 g/100 g dry matter. The starch hydrolysis index decreased (p < 0.05) as the level of DWRS increased, with a reduction of >20% comparing the 15-DWRS pasta to the control. DWRS had a negative impact on quality parameters, especially at higher DWRS levels. The use of DWRS shortened the optimal cooking time and impacted the samples’ cooking loss, firmness, and stickiness. In addition, sensory analysis revealed differences among samples. However, irrespective of the level of DWRS in the recipe, the score for all attributes was > 5, which is considered the limit of acceptability. Substituting part of the semolina flour with DWRS increased the level of RS and the overall nutritional profile and affected the quality of semolina pasta, mainly at higher levels in the recipe.

Metallic nanoparticles (MNPs) are becoming widespread environmental contaminants. They are currently added to several food preparations and cause a fast-growing concern for human health. The present work aims to assess the impact of zinc oxide (ZnO), titanium dioxide (TiO2), and silver (Ag) nanoparticles (NPs) on the human gut metabolome and microbiome. Water samples spiked with two different concentrations of each MNPs were subjected to in-vitro gastrointestinal digestion and in-vitro large intestine fermentation. The effects of the treatments were determined through 16 S amplicon sequencing and untargeted metabolomics. Multi-omics data integration was then applied to correlate the two datasets. MNPs treatments modulated the microbial genera Bifidobacterium, Sutterella, Escherichia and Bacteroides. The treatments, especially the lower concentrations of Ag and ZnO, caused modulation of indole derivatives, peptides, and metabolites related to protein metabolism in the large intestine. Notably, these metabolites are implicated in ulcerative colitis and inflammatory bowel disease. TiO2 NPs treatment in all concentrations increased E.coli relative abundance and decreased the abundance of B. longum. Moreover, for TiO2, an enrichment in proinflammatory lipid mediators of arachidonic acid metabo-lites, such as prostaglandin E2 and leukotrienes B4, was detected. For all metals except TiO2, low NP concen-trations promoted differentiated profiles, thus suggesting that MNPs aggregation can limit adverse effects on living cells.

Considering the high interest in using pulses in the production of staple foods, including pasta, this study aimed at investigating the effect of pre-gelatinisation on the overall quality of pasta from red lentils. Pre-gelatinized flours showed a lower gelatinisation temperature (up to about 57 °C vs. about 65 °C) and higher retrogradation tendency than native flour. Such changes resulted in higher water absorption capacity (up to 1.23 vs. 0.98 g g−1) and higher farinographic torque, but did not impact the cooking quality. Conversely, the resistant starch content of cooked pasta decreased (from 14.79 to 10.4 g/100 g total starch) and the starch hydrolysis index increased (from 48.28 to 67.71) when pre-gelatinised flours were used. In conclusion, pre-gelatinisation impacted starch, hydration and the mixing properties of red lentils flours, without compromising the cooking behaviour of the related pasta.

This study aims to provide information on the behaviour and biopersistence rate (BP) of metallic nanoparticles (Ag-NPs, TiO2-NPs, ZnO-NPs) naturally occurring in canned seafood and subjected to static in vitro digestion. Single particle ICP-MS analysis was performed to determine NPs distribution and concentrations in oral, gastric, and intestinal digests. Depending on the conditions of the digestive phase and the sample matrix, the phenomena of agglomeration and dispersion were highlighted and confirmed by Dynamic Light Scattering (DLS) technique. In standard suspensions, Ag-NPs had lower biopersistence (BP) than ZnO and TiO2-NPs (BP 34%, 89% and >100%, respectively). Among Ag-NPs and TiO2-NPs naturally present in the food matrix, those in canned tuna were more degradable than those in canned clam (BP Ag-NPs 36% vs. > 100%; BP TiO2-NPs 96% vs. > 100%), while BP ZnO-NPs showed high biopersistence in both seafood matrix (>100%). The biopersistence rates were higher than the recommended limit set by European Food Safety Authority (EFSA) (12%), referred to nanotechnologies to be applied in the food and feed chain, thus the investigated naturally occurring NPs cannot be considered readily degradable.

In this work, different commercial extra-virgin olive oils (EVOO) were subjected to in vitro gastrointestinal digestion and the changes in bioactive compounds were evaluated by ultra-highpressure liquid chromatography coupled with quadrupole-time-of-flight mass spectrometry, using untargeted metabolomics. As expected, raw EVOO samples were abundant in total sterols (on average: 3007.4 mg equivalents/kg) and tyrosol equivalents (on average: 334.1 mg equivalents/kg). However, the UHPLC-QTOF screening allowed us to annotate 310 compounds, with a large abundance of sterols (219 compounds), followed by polyphenols (67 compounds) and terpenoids. The in vitro gastrointestinal digestion was found to affect the phytochemical composition of the different EVOO samples. In particular, both unsupervised and supervised statistics depicted the modifications of the bioactive profile following gastric and pancreatic phases. Overall, the compounds which resulted as the most affected by the in vitro digestion were flavonoids (cyanidin and luteolin equivalents), whilst relatively high % bioaccessibility values were recorded for tyrosol equivalents during the pancreatic phase (on average, 66%). In this regard, oleuropein-aglycone (i.e., the major phenolic compound in EVOO) was converted to hydroxytyrosol, moving from an average value of 1.3 (prior to the in vitro digestion) up to 9.7 mg equivalents/kg during the pancreatic step. As proposed in the literature, the increase in hydroxytyrosol might be the result of the combined effect of lipase(s) activity and acidic conditions. Taken together, the present findings corroborate the suitability of untargeted metabolomics coupled to in vitro digestion methods to investigate the bioaccessibility of phenolic compounds. In this regard, a significant impact of in vitro gastrointestinal digestion on polyphenolic profiles has been detected, thus suggesting the need to account for actual bioaccessibility values rather than just considering the amoun

Artichoke is a relevant source of health-promoting compounds such as polyphenols and sesquiterpene lactones. In this study, the bioaccessibility and gut bioavailability of artichoke constituents were evaluated by combining in vitro digestion and large intestine fermentation, metabolomics, and Caco-2 human intestinal cells model. Moreover, the ability of artichoke polyphenols to modulate the in vitro starch digestibility was also explored. An untargeted metabolomic approach based on liquid chromatography quadrupole-time-of-flight (UHPLC/QTOF) mass spectrometry coupled with multivariate statistics was used to comprehensively screen the phytochemical composition of raw, digested, and fermented artichoke. Overall, a large abundance of phenolic acids and sesquiterpene lactones was detected, being 13.77 and 11.99 mgg1, respectively. After 20 h of in vitro large intestine fermentation, a decrease in polyphenols and sesquiterpene lactones content was observed. The most abundant compounds characterizing the raw material (i.e., chlorogenic acid and cynaropicrin equivalents) showed an average % bioaccessibility of 1.6%. The highest % bioaccessibility values were recorded for flavonoids such as anthocyanin and flavone equivalents (on average, 13.6%). However, the relatively high bioavailability values recorded for flavonols, phenolic acids, and sesquiterpene lactones (from 71.6% up to 82.4%) demonstrated that these compounds are able to be transported through the Caco-2 monolayer. The phenolic compounds having the highest permeation rates through the Caco-2 model included low molecular weight phenolics such as tyrosol and 4-ethylcatechol; the isoflavonoids 30-O-methylviolanone, equol 40-O-glucuronide, and hydroxyisoflavone; together with the methyl and acetyl derivatives of glycosylated anthocyanins. Therefore, although human in vivo confirmatory trials are deemed possible, current findings provide insights into the mechanistic eects underlying artichoke polyphenols and sesquit

Trub is a brewing by-product rich in proteins and fibers. We used trub, after a debittering step, at 5, 10, and 15 g/100 g (PT5, PT10, and PT15, respectively) to fortify durum wheat fresh pasta. Technological and physical–chemical properties, in vitro digestibility, and sensorial characteristics of fortified pasta were determined. The technological aspects of the products were peculiar, suggesting the existence of complex interactions between the gluten network and starch with debittered trub powder. The fortified pasta samples showed a lower glucose release than the control at the end of in vitro starch hydrolysis. Furthermore, in vitro protein digestion rose only in PT15. PT5 and PT10 samples overcame the sensory acceptability threshold of 5, while PT15 showed the lowest acceptability. Debittered trub represents a suitable ingredient in fortified fresh pasta formulation with an up to 10% substitution level without compromising the quality and sensory characteristics of the final product.

The untargeted metabolomic profile of five pigmented whole rice varieties, namely Ermes, Orange, Nerone, Venere, and Violet, was investigated. Samples were cooked to a comparable starch gelatinization level through an electric commercial rice cooker and in vitro digested to evaluate the fate of rice compounds during in vitro starch digestion. The untargeted metabolomics profiling depicted a broad phytochemical profile of rice grains, including phenolic compounds, terpenoids, and phytosterols, among others. Interestingly, the metabolomic profile showed distinctive shaping following cooking and in vitro digestion in a variety-dependent manner. Multivariate statistics revealed that glycosylated flavonoids and hydrolysis-products of tannins (such as 1,2-digalloyl-beta-D-glucopyranose) were the most discriminant compounds of the in vitro gastrointestinal digestion. The combination of cooking and simulated digestion was found to affect, in a matrix-driven manner, the profile of amino acids and lipids derivatives, together with sterols and terpenoids. Cooked Violet rice grains showed the lowest starch hydrolysis index (i.e., 58.2) and the highest resistant starch content (i.e., 4.8 g/100 g) compared to the other samples. Non-pigmented phenolic compounds could be included among discriminant compounds. After combining cooking and enzyme hydrolysis, Violet rice distinctively showed positive average LogFC values for flavonoids and phenolic acids. Overall, water-soluble anthocyanins were the most retained class of polyphenols following the cooking process, with peonidin 3-(6”-acetyl-glucoside) showing the highest discriminant potential (VIP score = 1.64).

BACKGROUND: Grape pomace (GP), a wine-making by-product rich in dietary fiber (DF) and total phenolic compounds (TPC), is a potential functional ingredient in the fortification of baked goods. RESULTS: In the present study, fortified breadsticks samples were obtained by replacing wheat flour with 0, 5 and 10 g 100 g−1 of powdered GP (GPP). The GPP inclusion affected the rheological properties of the doughs by increasing the water absorption and tenacity (P) at the same time as reducing the extensibility (L), with a significant increase in the P/L value and a decrease in the swelling index (G) value and deformation energy (W). Textural characteristics of breadsticks were influenced by the GPP addition, showing a reduction in hardness and fracturability as the amount of GPP increased in the recipe. The GPP fortified breadsticks exhibited decreased pH, volume and specific volume values compared to the control. The TPC and the antioxidant capacity increased in GPP fortified breadsticks, whereas the increased amount of DF allowed the products to benefit from the claim ‘high fiber content’ at the highest level of GPP inclusion. The sensory evaluation revealed that GPP addition increased wine odor, acidity, bitterness, astringency and hardness, and decreased the regularity of alveolation and friability. Finally, the GPP fortified products achieved good sensorial acceptability. CONCLUSION: GPP improved the nutritional values of fortified breadsticks and changed the rheology of dough and breadsticks' technological properties without affecting sensory acceptability. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

Pasta, a staple food worldwide consumed, was fortified with maqui (Aristotelia chilensis) berry powder (MBP) and the effect of MBP inclusion was evaluated concerning technological, nutritional, and sensory properties. Fresh pasta samples were formulated by replacing 0, 7.5, and 15 g 100 g−1 of durum wheat semolina with MBP. The inclusion of MBP did not affect the moisture content, but the water activity decreased in the fortified samples, while pH values decreased with increasing MBP levels in the recipe. The pasta fully cooking time and the swelling index were reduced, while the cooking loss and the firmness increased with increasing MBP levels. In addition, MBP increased the total dietary fiber, ash, and phenol contents, along with the in vitro antioxidant activities. The starch hydrolysis index and the predicted glycemic index of cooked fresh pasta decreased along with the increase of MBP addition. The MPB addition to fresh pasta could represent a valuable strategy for increasing its nutritional value, maintaining pasta’s technological properties without affecting the sensory acceptability.

Wheat-based vegan muffins were formulated with increasing levels (0, 5 and 10 g per 100 g substitutes to flour) of dried grape pomace powder obtained after distillation (DGPP). The DGPP-muffins showed a greater (P < 0.05) total dietary fibre and a lower (P < 0.05) total starch content to the control. The inclusion of DGPP influenced (P < 0.05) both the batter's rheological properties and the baked muffins' technological characteristics, including the baking loss, the volume, the firmness, the spread ratio and the colour. The in vitro antioxidant activity and the phenolic content increased (P < 0.05) following DGPP inclusion. The untargeted phenolic profiling by UHPLC-HRMS revealed an (P < 0.05) increase of several phenolic classes (i.e. free and bound fractions) following the inclusion of DGPP in the recipe. Flavonoids, mainly anthocyanins, were the most abundant compounds. A quantitative descriptive sensory analysis detected the DGPP-vegan muffins showed good sensory acceptability. The vegan muffin with 5 g per 100 g of DGPP obtained the highest overall acceptability score by the panellists.

Development of gluten-free (GF) pasta with improved nutritional attributes is one of the main trends in the gluten-free pasta industry. Considerable interest lays in introducing legume-based ingredients into traditional corn/rice GF formulations. This work aims to fortify multi-cereal (corn-rice) GF pasta with chickpea to investigate how different chickpea addition levels affect its quality and in vitro starch digestibility. Chickpea significantly increased pasta protein and dietary fibre contents to a level that supports the “source” or “high” fibre/protein content claims. Chickpea addition induced darkening, softening, adhesiveness decrease and solid loss reduction compared to the control. In addition, chickpea substitution significantly modified the in vitro starch digestion, which showed increasing resistant starch and decreasing slowly digestible starch contents suggesting potential mitigation of postprandial glucose response in vivo. Reformulating GF pasta with chickpea flour should, therefore, be considered as an effective tool to improve the corn–rice-based GF products' nutritional profile.

The interest in the modulation of gut microbiota by polyphenols from olives and derived products is increasing. In this work, phenolic leaf extracts (PLE) were in vitro faecal fermented to evaluate the changes in phenolic profiles and the impact on microbiota, using a commercial extra-virgin olive oil (EVOO) as reference. The in vitro fermentation decreased oleuropein content in PLE, determining an increase of hydroxytyrosol and other phenolic metabolites. An increase (p < 0.05) of hydroxytyrosol (LogFC = 6.02; VIP score = 1.05) was also observed in fermented EVOO. Besides, PLE significantly (p < 0.05) changed amino acids (LogFC = 6.1) and fatty acids (LogFC = 5.9) profile of the faeces. Metagenomic sequencing revealed that Coriobacteriaceae at the family level, and Collinsella at the genus level, were the most affected by PLE fermentation. These findings support the modulation of the gut microbiota exerted by phenolics from PLE and EVOO.

The fate of polyphenols from edible tree nuts was investigated using a simulated in vitro intestinal fermentation system. The digested food matrix was fermented for 48 h and the changes in the phenolic profiles were evaluated by both untargeted UHPLC-QTOF and targeted UHPLC-Orbitrap mass spectrometry. The untargeted metabolomics approach allowed us to monitor the comprehensive changes in phenolic profiles from 0 up to 48 h of in vitro fermentation. Multivariate statistics (i.e., orthogonal projection to latent structures discriminant analysis) applied to this untargeted data allowed us to identify the most discriminating phenolic metabolites and to further understand the colonic transformation pathways involved. In particular, 13 putatively identified compounds derived from flavonoids, lignans and phenolic acids were found to have the highest discrimination potential. Six phenolic metabolites were then quantified by means of targeted metabolomics (using a UHPLC-Orbitrap). These metabolites included 3,4-dihydroxyphenylacetic acid, 4-hydroxybenzoic acid, hippuric acid, caffeic acid, protocatechuic acid and protocatechuic aldehyde. Using the targeted data, a clear matrix effect was observed over time, with an increase of some phenolic metabolites moving from 8 to 48 h of in vitro fermentation. Based on these data, catabolic pathways for colonic microbial degradation of flavonoids, hydroxycinnamic acids, tyrosols and lignans are proposed. Our findings show that edible tree nuts deliver polyphenols to the colon, where several microbial transformations occur that lead to smaller phenolic metabolites being observed. Furthermore, we found that the combined use of targeted and untargeted metabolomics can be particularly effective for investigating the fate of polyphenols in the large intestine.

The interest in gluten-free (GF) products increases together with the increase in gluten-sensitive people. However, GF foods might have decreased nutritional quality as compared to the gluten containing counterparts. In this work, an investigation of the phenolic and antioxidant profile in 18 GF flours belonging to legumes, cereals and pseudocereals was achieved. Significant differences could be observed across samples. Total phenolic content was highest in violet rice flours, whereas total anthocyanins were highest in violet, nerone, and black rice flours. FRAP and ORAC antioxidant activities were correlated to phenolic contents and found to be higher in violet rice flours. Metabolomics highlighted a wide diversity in phenolics, with flavonoids (197 compounds ascribable to anthocyanins, flavones, flavanones, isoflavonoids, flavonols, and flavanols), phenolic acids (74 compounds belonging to hydroxycinnamics, hydroxybenzoics, and hydroxyphenylacetics), and tyrosol derivatives the most represented. Finally, OPLS-DA multivariate statistics outlined flavonoids, furofurans and phenolic acids as the most discriminant phenolics.

In an effort to promote the formation of resistant starch (RS), four different modification methods are applied to isolated white sorghum (WS) starch by subjecting the latter to heat‐moisture treatment (RSa), annealing (RSb), hydrolysis through pullulanase debranching enzyme (RSc), and dual autoclaving‐cooling cycles (RSd). Functional and physicochemical properties, individual RS content, and the behavior after cooking in terms of apparent RS retention (aRSr) of samples (i.e., WS, RSa, RSb, RSc, and RSd) are compared. Differences in thermal and pasting properties, in the ratio of ordered starch to amorphous starch, along with lower solubility and swelling power values, and greater water absorption capacity are measured in the four RS ingredients when compared to native WS starch. All the four modification methods prove to be similarly effective in increasing the amount of RS with respect to native WS starch, with an average 30% increase. However, based on the aRSr values, analyses revealed that the greater heat stability after cooking was obtained for RSb (93.7%) and decreased in the order of RSb>RSc>RSa = RSd>WS. Present results shed light on the properties of modified WS starch as a potential heat‐stable source of RS for food applications.

Alfalfa seed flour (ASF) at different inclusion levels (0% as control, 30% and 45% w/w) was used to prepare rice flour-based gluten-free (GF) cookies (CK). Samples underwent a simulated in vitro digestion and fermentation process. The comprehensive changes in the phenolic profiles were evaluated during 48 h of fermentation by means of untargeted UHPLC-QTOF mass spectrometry followed by multivariate statistics. Furthermore, the modifications in microbial profile and the production of short chain fatty acids (SCFA) were investigated. Cookies presenting 30% (30-CK) and 45% (45-CK) ASF possessed the greater total phenolic content when compared to the control, being 0.42 and 0.56 mg/g versus 0.15 mg/g, respectively. The orthogonal projection to latent structure discriminant analysis, applied to untargeted metabolomics-based data, showed a clear modulation of the profile in phenolic metabolites over time (from 8 up to 48 h of in vitro fermentation). In this regard, the in vitro fermentation of 30-CK and 45-CK resulted in the maximum increase in lignans and phenolic acids, whose bioaccessibility at 24 h of in vitro fermentation was 16.2% and 12.2%, respectively. In addition, the metagenomic sequencing approach allowed to identify in Clostridiaceae, Ruminococcaceae, Lachnospiraceae and Streptococcaceae the most represented bacterial populations during the in vitro fermentation. A greater total SCFA production (p < .05) was recorded overtime for all ASF-enriched cookies when compared to the control. Therefore, ASF proved to be an excellent alternative to common non-wheat cereal flours (such as pseudocereals or legumes) for improving possible health-promoting properties in GF cookie formulation.

The effects of conventional extrusion (CV) and extrusion-cooking (EC) were investigated on 100% yellow lentils (YL). Both the extrusion processes led to pasta with good cooking quality (cooking loss: 7.0–7.1 g/100 g, firmness: 530–608 N), even in overcooking (cooking loss: 7.7–7.9 g/100 g, firmness: 418–513 N). Contrary to what is known for gluten-free cereals, CV is effective in producing pasta from native YL with no need for a pre-gelatinization step. However, pasta from EC showed a higher compression energy (2898 versus 2448 N*mm). In this sample, starch presented a higher degree of gelatinization (75.5 versus 57.6 g/100 g) and lower enthalpy (0.97 versus 1.07 J/g). At the same time, EC promoted a more compact structure that required higher temperature for melting (66.49 versus 63.16 °C) and showing pasting properties (79.1 versus 74.7 °C). Thus, by selecting suitable extrusion conditions it is possible to improve the cooking behavior of 100% pulse pasta.

Moringa (Moringa oleifera Lam.), the so-called ‘miracle tree’, has emerged as an excellent source of nutrients and functional components also in food applications. In this regard, Moringa is worldwide cultivated for its nutritional properties and for a variety of end-uses. The different portions of this plant (leaves, pods, seeds) have been widely studied for their antioxidant, anti-inflammatory, and antihyperglycemic activities. Most of the functional activities reported in the literature are strictly related to its high content of polyphenols, bioactive peptides, carotenoids, and glucosinolates. Besides, a great interest is emerging towards the exploitation of Moringa as a value-added ingredient for both bakery and meat products. On these bases, considering the more recent literature about M. oleifera plant, this short review aims to highlight the different biological and potential food applications of M. oleifera parts and/or extracts as a source of bioactive compounds able to provide health-promoting properties.

Gluten-free (GF) pasta samples containing rice flour replaced with 0, 5, 10, 15 g/100 g (w/w) of a resistant starch ingredient from annealed sorghum starch (annRS) were formulated. The highest total dietary fiber and RS contents (p < 0.05) were measured in uncooked pasta with 15 g/100 g of annRS addition (15-annRS). After cooking, the 15-annRS pasta was characterized by an RS content of 5.8 g/100 g dry matter, confirming the thermal resistance of annRS. The use of annRS positively influenced the optimal cooking time, the cooking loss, the firmness, and the stickiness of the cooked samples, with not remarkably change in color after cooking. The starch hydrolysis index values decreased as the level of annRS increased. Despite a significant decrease in the overall sensory with increasing levels of annRS, all samples were characterized by a value > 5, which is considered the limit of acceptability. The use of annRS in GF pasta up to 15 g/100 g can contribute to creating GF products with high total dietary fiber content, slowly digestible starch properties, and without drastically compromising the sensory attributes.

Frozen food sees a continuous increase in consumption thanks to the capability to preserve the organoleptic properties and, at the same time, to increase the shelf-life of the food itself. Therefore, a proper design of the freezing process is crucial and is strictly related to an accurate evaluation of freezing time because this establishes the minimum residence time of the product in a continuous freezer. For this reason, several mathematical models have been proposed and investigated for predicting the freezing time, starting from empirical models (lower accuracy and computational time) up to computational fluid dynamics simulation (higher accuracy and computational time). An excellent compromise between accuracy and computational effort seems to be a model that combines empirical laws for property evaluation and heat diffusion equation solved in one dimension. This model can numerically be solved using the method of lines in which spatial derivatives are discretized by the finite difference method and the resulting system of ordinary differential equations is integrated using an appropriate solver. This work aimed to fill some gaps to develop a comprehensive and more accurate model for freezing time prediction. Indeed, the key idea is to validate a model that could be used to optimize the refrigeration process for energy-saving and be the base for a design of experiment in case of lack of experimental data. The newly developed model includes the evaluation of freezing time for finite food shapes because, in some cases, it is not possible to assume a characteristic direction for heat flux. The property of unfrozen and frozen food (e.g. density, thermal conductivity, apparent specific heat, etc.) are evaluated basing on the principal constituent of food (e.g. water, fiber, protein, etc.), while heat transfer coefficient is evaluated using empirical equations, depending on adimensional numbers. In this way, it is possible to be flexible and not strictly related to t

Grape pomace powder (GPP), a by-product from the winemaking process, was used to substitute flour for wheat bread fortification within 0, 5, and 10 g/100 g. Rheological properties of control and fortified doughs, along with physicochemical and nutritional characteristics, antioxidant activity, and the sensory analysis of the obtained bread were considered. The GPP addition influenced the doughs’ rheological properties by generating more tenacious and less extensible products. Concerning bread, pH values and volume of fortified products decreased as the GPP inclusion level increased in the recipe. Total phenolic compounds and the antioxidant capacity of bread samples, evaluated by FRAP (ferric reducing ability of plasma) and ABTS (2,20-azino-bis (3-ethylbenzothiazoline-6-sulfonic acid)) assays, increased with GPP addition. Moreover, the GPP inclusion level raised the total dietary fiber content of bread. Regarding sensory evaluation, GPP fortification had a major impact on the acidity, the global flavor, the astringency, and the wine smell of bread samples without affecting the overall bread acceptability. The current results suggest that GPP could be an attractive ingredient used to obtain fortified bread, as it is a source of fiber and polyphenols with potentially positive effects on human health.

Gluten-free (GF) biscuits were prepared by replacing part of a GF flour mix (GFM) with 0, 15, 30 and 45 g/100 g (total flour) with a novel resistant starch-rich ingredient obtained from annealed white sorghum starch (RSWS). The chemical composition, physical characteristics, in vitro starch digestion and sensory evaluation of biscuits, were considered. The chemical composition of samples was influenced by the addition of the RSWS. The highest total dietary fibre and RS contents (p < 0.05) were measured in 45-RSWS biscuits. The starch hydrolysis index values decreased when the level of RSWS increased in the composite. With regard to quality parameters, the use of RSWS influenced the hardness of the biscuits, and the highest value obtained for 45-RSWS. Some of the selected sensory attributes, along with the overall acceptability score, were negatively influenced by the RSWS addition, even if all remained above the limit of acceptability. The use of RSWS in GF biscuit formulation can contribute towards the creation of food products likely having slowly digestible starch properties, and this can be achieved without drastically compromising on the quality and sensory attributes.

Breads were prepared by substituting common wheat flour with 0 (GP0), 5 (GP5) and 10 (GP10) g/100 g (w/w) of grape pomace powder (GPP) and were analyzed for the phenolic profile bioaccessibility as well as the in vitro starch digestion during simulated digestion. The free and bound phenolic composition of native GPP and resulting breads were profiled using ultra-high-performance chromatography-quadrupole-time-of-flight (UHPLC-QTOF). The raw GPP was characterized by 190 polyphenols with the anthocyanins representing the most abundant class, ac-counting for 11.60 mg/g of cyanidin equivalents. Regarding the fortified bread, the greatest (p < 0.05) content in phenolic compounds was recorded for the GP10 sample (considering both bound and free fractions) being 127.76 mg/100 g dry matter (DM), followed by the GP5 (106.96 mg/100 g DM), and GP0 (63.76 mg/100 g DM). The use of GPP determined an increase of anthocyanins (considered the markers of the GPP inclusion), recording 20.98 mg/100 g DM in GP5 and 35.82 mg/100 g DM in GP10. The bioaccessibility of anthocyanins increased in both GP5 and GP10 breads when moving from the gastric to the small intestine in vitro digestion phase with an average value of 24%. Both the starch hydrolysis and the predicted glycemic index decreased with the progressive inclusion of GPP in bread. Present findings showed that GPP in bread could promote an antioxidant environment in the digestive tract and influence the in vitro starch digestion.

The purpose of this preliminary study was to discriminate the chemical fingerprints of Protected Designation of Origin (PDO) Grana Padano cheeses from non-PDO “Grana-type” cheeses by means of an untargeted metabolomic approach based on ultra-high-pressure liquid chromatography coupled to quadrupole time-of-flight mass spectrometer (UHPLC/QTOF-MS). Hierarchical cluster analysis and Orthogonal Projections to Latent Structures Discriminant Analysis (OPLS-DA) allowed discriminating PDO vs. non-PDO cheeses. Lipids (fatty acids and their derivatives, phospholipids and monoacylglycerols), amino acids and oligopeptides, together with plant-derived compounds were the markers having the highest discrimination potential. It can be postulated that Grana Padano value chain, as strictly defined in the PDO production specification rules, can drive the biochemical processes involved in cheese making and ripening in a distinct manner, thus leaving a defined chemical signature on the final product. These preliminary findings provide the basis for further authenticity studies, aiming to protect the designation of origin of PDO Grana Padano cheese by applying a comprehensive foodomics-based approach.

Interest in using polyphenols as modulators of the activity of starch digestive enzymes is increasing. The main purpose of this study was to investigate the role of phenolic compounds characterising pigmented maize flours in the modulation of in vitro starch digestibility. Flours from three different pigmented maize varieties were evaluated under cooking conditions and compared to common yellow maize (YM). The untargeted metabolomics-based approach comprehensively annotated around 300 phenolic compounds, with a high distribution of anthocyanins and phenolic acids (in free and bound fractions of maize samples) and significant differences across genotypes. Following in vitro starch digestion, the cooked pigmented maize flours showed higher resistant starch content (from 5.1 to 6.9 g /100 g dry matter), as well as lower starch hydrolysis index (HI) when compared to YM flour, with the “Rostrato Rosso” maize having the lowest HI (i.e., 61). Coherently, multivariate statistics following metabolomics showed the discrimination potential of anthocyanins' profile after cooking, characterising the “Rostrato Rosso” during in vitro digestion. These findings might be related to the modulation of enzyme activity by phenolic compounds during in vitro digestion. Therefore, the use of pigmented maize flours might help in the formulation of gluten-free foods with slowly digestible starches by exploiting the wide phenolic composition of these matrices.

In an effort to increase the nutritional value of common gluten-free (GF) cereal-based foods, GF cookies using alfalfa seed flour (ASF), at different substitution levels to common rice flour (0% as control, 15%, 30% and 45% w/w), were produced. Crude protein, total dietary fibre, total polyunsaturated, total n-3 and n-6 fatty acid contents increased linearly (pÂ&nbsp

Commercially available gluten-free (GF) cereal-based foods are generally characterised by a lower nutritional quality than their gluten-containing counterparts, relatively lower resistant starch (RS) content, along with higher glycaemic index (GI) often being reported. To overcome this nutritional imbalance, extensive research has been conducted to investigate the preparation of a new generation of staple GF products. This review reported the main strategies currently adopted in GF cereal-based food recipes to formulate products with overall slowly digestible starch properties. They are mainly obtained by the utilisation of alternative ingredients to be incorporated into standard food formulation (including native starch and GF flours) or by technological treatments that may contribute to impact starch digestibility. Considering data from in vitro digestion trials, indications suggested that, aiming to obtain a RS content of about 5% (dry weight) and lowering the in vitro GI values, the minimum high amylose starch (amylose >60%) replacement level in GF bread and cookie formulations should be in the order of 20% by weight of total flours. Overall, with respect to un-substituted GF foods, two- to three-times higher RS contents, along with a parallel in vitro GI decrease (up to −50%), were obtained for GF pasta and ready-to-eat snacks enriched with legume flours at inclusion levels from 40% to 100% by weight of total flours. The use of flours from pseudocereals (e.g., quinoa, amaranth and buckwheat) with and without sourdough did not always guarantee favourably slowly digestible starch GF foods.

In recent years, the enhancement of common gluten-free (GF) cereal-based foods with ingredients rich in phytochemicals such as polyphenols (PP) is gaining interest. However, the comprehensive screening of PP is complex due to their chemical diversity, as well as because many of them are found at low concentration levels, as conjugated forms, and because they do undergo transformation by the colonic microflora. With this aim, the high-resolution mass spectrometry based metabolomics profiling may provide more inclusive information concerning the identification, quantification and dynamics of PP in complex matrices. This mini-review is focused on the potential of metabolomics in the untargeted evaluation of phenolic profile and bioaccessibility in GF cereal-based food products.

Dried powder from Moringa oleifera L. leaves (MOLP) could be considered a promising naturally gluten-free (GF) ingredient to be added in the formulation of GF food products aiming to improve the overall nutritional characteristics. In this work, GF biscuits were formulated by replacing a commercial GF flour mix with 0, 5, 10, and 15 g/100 g of MOLP. Chemical composition, physical and textural characteristics, starch pasting properties, and the in vitro starch digestibility were considered. Adding MOLP increased the amount of protein and total dietary fibre. Even at the lowest MOLP-substitution level, the biscuits had a total dietary fibre content > 6 g/100 g dry matter. Differences in the chemical composition might account for differences in starch properties in terms of pasting behaviour and in vitro digestibility. Using MOLP decreased the in vitro starch hydrolysis index of biscuits, the lowest value (69.3) obtained at the greatest MOLP inclusion level. In addition, an increase in the resistant starch content was reported, passing from 1.1 to 2.7 g/100 g dry matter for GF biscuits containing 0 to 15 g/100 g of MOLP. Colour, spread ratio, and hardness were affected by MOLP inclusion. Biscuits containing 15 g/100 g of MOLP were characterized by the highest hardness value (41.9 N). Substitution level of 10 g/100 g should be considered the threshold level for obtaining a product with similar spread ratio than the control.

In this study, the untargeted phytochemical profile of non-edible parts of pomegranate (i.e., flowers, leaves and peels) was depicted by using untargeted metabolomics. Each sample was in vitro digested and then fermented simulating a large intestinal process, then monitoring the changes of phenolic bioaccessibility. The most abundant compounds in pomegranate extracts were polyphenols, terpenoids, sterols, alkaloids and amino acids. The untargeted metabolomic approach revealed a transformation of flavonoids over 24 h of in vitro fermentation. In particular, an increase in the % bioaccessibility for phenolic acids and tyrosols in flowers (probably due to the insoluble dietary fibre content, i.e., 27.1 g 100 g−1) was observed. Accordingly, the highest % bioaccessibility was detected after 24 h of in vitro large intestine fermentation for flower (i.e., 53.8%). Results showed that non-edible parts of pomegranate could be used as ingredients for the development of potential value-added food and industrial products.

This study is aimed to comparatively investigate the phytochemical profiles, focusing on the nutritional and phytochemical properties of common garlic (Allium sativum L.; CG) and elephant garlic (EG) (Allium ampeloprasum var. holmense) collected from the Val di Chiana area (Tuscany, Italy). The results showed a lower amount of fibers, demonstrating a higher digestibility of the bulb, and sulfur-containing compounds in EG rather than in CG. Untargeted metabolomic profiling followed by supervised and unsupervised statistics allowed understanding the differences in phytochemical composition among the two bulbs, both as raw bulbs, processed following the in vitro gastrointestinal digestion process. Typical sulfur-containing compounds, such as alliin and N-gamma-glutamyl-S-allyl cysteine, could notably be detected in lower amounts in EG. EG maintains a distinct phytochemical signature during in vitro gastrointestinal digestion. Our findings support the distinct sensorial attributes of the bulbs.

Polyphenols are reported to modulate starch digestibility via either direct inhibition of alpha-glycosidase digestive enzymes and/or the formation of inclusion and non-inclusion complexes with starch. In particular, the former process results from binding interactions between phenolics and the free enzymes. Concerning the latter process, recent evidences support specific non-covalent bonds between different polyphenols (mainly flavonoids, phenolic acids and tannins) and carbohydrate polymers via hydrogen bonds and hydrophobic interactions. This role played by phenolics towards starch digestibility could represent a valid strategy to design functional foods and/or to manage type II diabetes. This short-review provides an updated and critical overview on the complex interactions occurring between phenolic compounds and amylolytic enzymes within the food-matrix and during food digestion, together with the postulated effects provided by polyphenols-starch interactions on starch digestibility. Noteworthy, considering that the most recent works on this topic are from in vitro studies, further in vivo research is deserved.

Polyphenols from five pigmented sorghum (PS) flours were in vitro evaluated as possible modulators of starch digestibility. White sorghum (WS) flour was used as control. Untargeted metabolomics depicted the phenolic composition of raw and cooked flours (obtained through heating at 100 °C for 30 min in water) highlighting differences in flavonoids and phenolic acids. Raw PS flours were characterized by greater tannin and kafirin contents when compared to WS, and, after cooking, PS flours had greater resistant starch (from 4.2 to 21.4 g /100 g dry matter), and lower starch hydrolysis index (HI) with respect to cooked WS. Multivariate statistics showed that flavonoids characterizing PS were the most discriminant compounds during the in vitro digestion. In addition, kafirin and total tannins content (on raw ingredients) along with the anthocyanin profiles (on cooked samples) were negative correlated with HI. Therefore, PS flours might be good candidates for the formulation of functional foods.

Fresh pasta was formulated by replacing wheat semolina with 0, 5, 10, and 15 g/100 g (w/w) of Moringa oleifera L. leaf powder (MOLP). The samples (i.e., M0, M5, M10, and M15 as a function of the substitution level) were cooked by boiling. The changes in the phenolic bioaccessibility and the in vitro starch digestibility were considered. On the cooked-to-optimum samples, by means of ultra-high-performance liquid chromatography-quadrupole time-of-flight (UHPLC-QTOF) mass spectrometry, 152 polyphenols were putatively annotated with the greatest content recorded for M15 pasta, being 2.19 mg/g dry matter (p < 0.05). Multivariate statistics showed that stigmastanol ferulate (VIP score = 1.22) followed by isomeric forms of kaempferol (VIP scores = 1.19) and other phenolic acids (i.e., schottenol/sitosterol ferulate and 24-methylcholestanol ferulate) were the most affected compounds through the in vitro static digestion process. The inclusion of different levels of MOLP in the recipe increased the slowly digestible starch fractions and decreased the rapidly digestible starch fractions and the starch hydrolysis index of the cooked- to-optimum samples. The present results showed that MOLP could be considered a promising ingredient in fresh pasta formulation.

The valorisation and the reuse of agricultural residue and food waste are gaining more attention in the last years as are directly related to environmental sustainability. For this reason, the aim of this study is to evaluate the influence of autohydrolysis operating conditions for a high yield recovery of sugars, soluble fiber and antioxidants from grape skins. In this work, an experimental campaign using a lab-scale batch autohydrolysis reactor is scheduled based on statistical methods to assess the influence of some process variables (like water to skins solids ratio or working temperaure) on some selected key performance indicators (KPIs), like sugars, sugar degradation products, phenolic compounds, antioxidant compounds and fiber recovery. As a comparison, different agricultural residue, like wheat straw, are considered. Entering in the details, the volume of the recovered autohydrolysis liquid fraction is measured and analyzed to calculate the release yield of both total solids and specific components, including antioxidant activity according different in vitro assays tests such as and ABTS assay. Therefore, this work presents an innovate autohydrolysis process for the valorization of waste grape skins for the production of added-value compounds through a potentially green technology.

The aim of this study was to investigate the modulation of polyphenols profile of blackberry purees by soluble dietary fibres (inulin or pectin), during a simulated in vitro gastrointestinal digestion and large intestine fermentation process. Untargeted profiling evidenced that the free phenolic fraction of blackberry puree was characterized mainly by flavonoids, followed by phenolic acids, lignans and other low molecular weight polyphenols, showing clear differences from the bound phenolic fraction detected. This trend could be related to the interactions of dietary fibre and polyphenols, showing synergistic and/or antagonist effect on the bioactivity of polyphenols. On the other hand, in vitro large intestine fermentation of blackberry purees following in vitro gastrointestinal digestion revealed that the highest inclusion level (10% w/w) of soluble dietary fibres was effective in modulating the bioaccessibility of some phenolic classes (mainly phenolic acids, lignans and flavones) characterizing the blackberry puree. In addition, multivariate statistics following metabolomics-based profiling showed that the interaction between fibres and blackberry purees determined a marked modification of both anthocyanins and flavonols during in vitro large intestine fermentation, thus leading to the formation of low-molecular-weight compounds (such as tyrosol, followed by gallic and benzoic acids).

Food science; Food technology; Resistant starch; In vitro fermentation; SCFA production; Dietary fibre; Butyrate

Experimental gluten-free (GF) rice cookies were formulated with 100% rice flour (CTR) or by substituting 50% of rice flour with native waxy rice starch (WRS) or with three different resistant starch (RS) ingredients obtained from debranched, annealed or acid and heat-moisture treated WRS (RSa, RSband RSc, respectively). Chemical composition, in vitro starch digestibility and physical and textural characteristics were carried out. Among cookies, RSa-cookies had the highest total dietary fibre content, the lowest rapidly digestible starch and the highest RS contents. All the three RS preparations have proved effective in increasing the proportion that tested as RS with respect to native WRS. However, the estimated RS loss for each applied RS ingredients caused by the baking process followed the order of RSa< RSc< RSb. Last, the lowest vitro glycaemic index value was measured for RSa-cookies. Among cookies, differences in colour and hardness were reported. The partial replacement of commercial rice flour with RSacould contribute to formulate GF cookies with higher dietary fibre content and likely slowly digestible starch properties more than equivalent amounts of RSband RSc.

The purpose of this study was to observe, in a rat animal model, the short and medium term effects of vegan (VEG) or omnivorous (OMNI) diets with different energy partition between nutrients (zone or classic). Six different diets were administered, for 72 days to 120 growing male Sprague-Dawley rats: (i) VEG zone diet; (ii) VEG classic diet; (iii) OMNI zone diet; (iv) OMNI classic diet; (v) OMNI zone diet with added fibre and (vi) OMNI classic diet with added fibre. Zone diets (high protein and low carbohydrates), resulted in better growth, feed efficiency, lower blood glucose and insulin responses. VEG diets have lowered cholesterol blood level. Histopathological analysis evidenced no damage to liver and kidney tissue by the intake of any of the diet types. Further longer animal and human duration studies should be performed to exclude detrimental effect of higher protein diet.

Cooking by boiling dry pasta could have varying degrees of influence on nutritional and functional components. In the present study, its effect on total phenolic content and antioxidant capacity, as well as on the comprehensive profile of free and bound phenolics, was investigated in six commercial gluten-free (GF) pasta products. Overall, the heat treatment caused a significant reduction (P < 0.01) of the total phenolic content as well as FRAP reducing power and ORAC radical scavenging, with significant differences among the pasta samples considered. The highest values were recorded in free phenolic fraction remaining in black rice (41 mg gallic acid equivalents 100 g− 1 and 25 mmol Trolox Equivalents 100 g− 1) and quinoa (24 mg gallic acid equivalents 100 g− 1 and 14 mmol Trolox Equivalents 100 g− 1) cooked GF pasta. Significant correlations (P < 0.01) could be found between total phenolics and both the antioxidant capacity assays performed. UHPLC-ESI/QTOF-MS mass profiling allowed confirming the spectrophotometric results, while identifying the amount of free and bound fractions. Among phenolic classes, lignans exhibited the highest decrease during the cooking process, followed by stilbenes and flavonoids. However, phenolic acids and other phenolics showed the highest stability. Furthermore, cooking by boiling strongly lowered the bound-to-free ratio of phenolic compounds, by an averaged factor ranging from 14-folds for flavonoids to 5-folds for other classes of phenolics.

The fate of phenolic compounds, along with short-chain fatty acids (SCFAs) production kinetics, was evaluated on six different commercial gluten-free (GF) pasta samples varying in ingredient compositions, focussing on the in vitro faecal fermentation after the gastrointestinal digestion. A general reduction of both total phenolics and reducing power was observed in all samples, together with a substantial change in phenolic profile over 24 h of faecal fermentation, with differences among GF pasta samples. Flavonoids, hydroxycinnamics and lignans degraded over time, with a concurrent increase in low-molecular-weight phenolic acids (hydroxybenzoic acids), alkylphenols, hydroxybenzoketones and tyrosols. Interestingly, discriminant analysis also identified several alkyl derivatives of resorcinol as markers of the changes in phenolic profile during in vitro fermentation. Furthermore, degradation pathways of phenolics by intestinal microbiota have been proposed. Considering the total SCFAs and butyrate production during the in vitro fermentation, different fermentation kinetics were observed among GF pasta post-hydrolysis residues.

The characterization of phenolic fingerprints in common gluten-free flours is still scarce. Total phenolic and anthocyanin contents, antioxidant capacity and the entire phenolic profile were investigated for extracts from chickpea, sorghum, quinoa, black rice, lentil, amaranth, brown rice, oat and white rice flours, using soft wheat flour as a comparison. The highest phenolic content was found in black rice, followed by quinoa extracts (147.9 and 87.2 mg gallic acid equivalents 100 g−1, respectively). Consistently, antioxidant capacity was highest in black rice and quinoa flours (34 mmol trolox equivalents 100 g−1), while anthocyanins were highest in black rice flour. Data showed a high correlation between phenolic content and both reducing and scavenging activities, with Pearson's coefficient of 0.90 and 0.91, respectively. Although the entire phenolic profile was diverse and differed among flours, these represent a valuable source of health-promoting compounds, mainly belonging to flavonoids, phenolic acids and lignans.