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Grape processing generates large amounts of by-products, including seeds rich in hydrophilic and lipophilic antioxidants. This study demonstrates, for the first time, that subjecting grape seeds to a single ultrasound-assisted extraction (UAE) with aqueous ethanolic solutions yields both flavan-3-ols and tocochromanols in the final extract. Notably, the water content in ethanol significantly influences the extractability of tocochromanols more than flavan-3-ols. Solid-to-solvent ratios of 1:50 to 1:2 were tested for both analytical and industrial applications. A sustainable analytical approach for recovering flavan-3-ols and tocochromanols using 60% and 96.4% ethanol extractions was validated and employed to profile nineteen genotypes of lesser-studied interspecific grape crosses (Vitis spp.). Different genotypes showed a wide range of concentrations of tocopherols (1.6–6.3 mg/100 g), tocotrienols (1.0–17.4 mg/100 g), and flavan-3-ols (861–9994 mg/100 g). This indicated that the genetic background and maturity of the plant material are crucial factors from an industrial perspective due to the initial concentration of bioactive compounds. Finally, the study also discussed the fundamental aspects of hydrophobic antioxidant extractability from the lipid matrix with aqueous ethanol solutions and the limitations of the workflow, such as the non-extractable tocochromanols and their esters and the losses of these lipophilic antioxidants during extraction. [Display omitted] • Seeds of grape crosses (Vitis spp.) consist of diverse phytochemical profiles. • Sustainable water-ethanol methods for phytochemical extraction were proposed. • Tocochromanols are co-extractable during the flavan-3-ols recovery from grape seeds. • Solid-to-solvent ratios 1:50 and 1:2 tested for analytical and industry applications. • The presence of non-extractable and bound tocochromanols in grape seeds was studied. [ABSTRACT FROM AUTHOR]

Highlights • Phenolic extraction followed in wines made from Shiraz grapes of different ripeness degree. • As fermentation progressed more phenolics extracted in wines made from riper grapes. • Cell wall polysaccharide deconstruction was a determining factor for phenolic extractability. Abstract This study evaluated the relationship between cell wall breakdown, from Shiraz grapes harvested at three different ripeness levels and the colour and phenolics extracted during alcoholic fermentation into wines. Phenolic differences between the ripeness treatments were minimal after ¼ of the fermentation was completed. However, colour and phenolic content were significantly higher in finished wines made from 25°Brix grapes compared to those from 21°Brix and 23°Brix. Levels of grape cell wall polysaccharide deconstruction during fermentation was a determining correlative factor in relation to phenolic extractability. In this context, the de-pectination observed during ripening was found to enhance this deconstruction or "opening-up" of the grape pomace during fermentation, thus increasing the differential extraction of specific polyphenols, especially polymeric polyphenols, into the wines. Additionally, the degree of cell wall deconstruction seemed to play a role in the possible retention and extraction of specific grape proanthocyanidins, depending on their nature and polymer length. [ABSTRACT FROM AUTHOR]

Highlights • Sample matrices significantly affect in vitro immunodetection of food allergens. • Matrix affected more on the thermostability of salmon parvalbumin than mullet's. • Extractability and immunodetection of parvalbumin were affected by SDS, βME or EDTA. • The entire amino acid sequence of mullet parvalbumin is reported for the first time. Abstract Two fish parvalbumin models were established to study relationships among matrix effect, extractability, and thermostability during in vitro immunodetection using two parvalbumin-specific monoclonal antibodies (3E1 and PARV19). Our results illustrated that matrix-induced thermal instability of parvalbumin was due mainly to physical (hydrophobic effect) and chemical (thiol-disulfide interchange) interactions. The addition of sodium dodecyl sulfate (SDS, surfactant), β-mercaptoethanol (reducing agent) or ethylenediaminetetraacetic acid (EDTA, metal chelator) during sample preparation could not only increase the extractability of parvalbumin but also enhanced its immunodetection. Our findings demonstrated excess EDTA completely chelated Ca2+ in parvalbumin and rendered it undetectable using PARV19 (a Ca2+-dependent antibody). Overall, our resulted showed that matrix effect on in vitro analyte quantification cannot be underestimated. Any false negative or positive results could lead to severe or life-threatening allergic reactions. [ABSTRACT FROM AUTHOR]

Oat bran was fermented by filamentous fungi to improve the extractability of β -glucan. Box-Behnken experimental design and response surface methodology were used to obtain the maximum extractability of β -glucan. Inoculum volume, fermentation temperature, and time were evaluated as three variables. Under optimal fermentation conditions, the extractability of β -glucan in oat bran increased to 45.57 ± 1.82% and 51.10 ± 2.32% by Aspergillus niger and Rhizopus oryzae , respectively. The extractability was about 3-fold of that before fermentation (16.86 ± 0.76%). Fermentation of oat bran by Aspergillus niger and Rhizopus oryzae reduced the molecular weight of the extracted β -glucan from 6.74 × 10 5 to 2.84 × 10 5 and 2.20 × 10 5  Da, respectively. Correspondingly, the apparent viscosity of the extracted β -glucan decreased after fermentation. But the increased extractability compensated for the reduced molecular weight in the formation of viscous solution. The molecular structure and cellotriosyl/cellotetraosyl ratio were not affected by filamentous fungi fermentation. [ABSTRACT FROM AUTHOR]

Postharvest withering of grapes strongly affects the content and extractability of phenolic compounds in the production of sfursat, fortified and passito wines. This work evaluated the effectiveness of enzymes applied individually and/or in multi-enzyme blends, on the extraction of anthocyanins, oligomeric flavanols and polymeric flavanols from withered grape skins during simulated maceration. The study was performed on Vitis vinifera L. cv. Nebbiolo and Barbera because of their different skin phenolic profile and cell wall composition. Our findings highlight that the relationship between skin mechanical properties (berry skin break force and energy) and extraction yield of phenolic compounds is variety dependent. Significant correlations were found between the skin softening associated with cell wall degradation and the extraction of anthocyanins and flavanols in Nebbiolo, for which polygalacturonase, individually or in multi-enzyme blends, plays an important role. In Barbera, the extractability of phenolic compounds was not affected by the presence of exogenous enzymes. [ABSTRACT FROM AUTHOR]

The hard-to-cook (HTC) defect in legumes is characterized by the inability of cotyledons to soften during the cooking process. Changes in the non-starch polysaccharides of common bean seed coat and cotyledon were studied before and after development of the HTC defect induced by storage at 35 °C and 75% humidity for 8 months. Distinct differences in the yields of alcohol insoluble residues, degree of methoxylation (DM), sugar composition, and molar mass distribution of non-starch polysaccharides were found between the seeds coat and cotyledons. The non-starch polysaccharide profiles, both for seed coats and cotyledons, significantly differed when comparing HTC and easy-to-cook (ETC) beans. In conclusion, differences in the structure, composition and extractability of non-starch polysaccharides between the ETC and HTC beans confirmed the significant role of pectin polysaccharides in interaction with divalent ions in the HTC development, which consequently affect their cooking behaviors. [ABSTRACT FROM AUTHOR]

The rate of tannin extraction was studied in a vinification of red grapes and the results compared with another vinification made with white grapes fermented as for typical red wine, in the presence of skins and seeds. Even though the grapes presented a quite similar skin and seed tannin content, the differences in tannin concentration between both vinifications was very large, despite the fact that the only apparent difference between the phenolic composition of both wines was the anthocyanin content. This suggests that anthocyanins play an important role in tannin extractability, perhaps because they affect the extent of the tannin–cell wall interaction, a factor that largely controls the resulting quantity of tannins in wines. To confirm this observation, the effect of anthocyanins on the tannin extractability from grape seeds and skin and on the interaction between tannins and grape cell walls suspended in model solutions were studied. The results indicated that anthocyanins favored skin and seed tannin extraction and that there is a competition for the adsorption sites between anthocyanins and tannins that increases the tannin content when anthocyanins are present. [ABSTRACT FROM AUTHOR]

Abstract: Two faba bean (Hudieba-72 and Bsabir) and three white bean (Serge, Giza and RO21) cultivars were sprouted for 6days. The sprouted grains were dried and milled. Phytic acid and polyphenols contents and hydrochloric acid (HCl) extractability of minerals from the malt flours were determined at intervals of 2days during sprouting. Phytic acid and polyphenols contents decreased significantly (P ⩽0.01) with increase in sprouting time with concomitant increase in HCl extractable major and trace minerals. The contents of both major and trace minerals were slightly increased with sprouting time. When faba bean seeds were sprouted for 6days, Bsabir had higher extractable Ca, while Hudieba-72 had higher P, whereas Fe and Mn recorded high level in Hudieba-72. When white bean seeds were sprouted for 6days, RO21 cultivar had higher extractable Ca, while Giza-3 cultivar had higher P, whereas Fe and Mn recorded high levels in Serge and RO21 cultivars, respectively. There was a good correlation between phytate and polyphenols reduction and increase in extractable minerals with increase in sprouting time for all cultivars. [Copyright &y& Elsevier]

Abstract: To assess the potential of arabinoxylan (AX)-rich psyllium (Plantago ovata Forsk) seed husk (PSH) as a source for production of arabinoxylo-oligosaccharides (AXOS), the parameters determining PSH AX extraction yield and the chemical and enzymic hydrolysis of PSH AX were investigated. The seed husk material had a high content of AX (62.5%) with an arabinose to xylose ratio of 0.41. The water extractability of PSH AX was affected by suspension concentration rather than by temperature. Maximally, 27% of all AX could be extracted, even when using very dilute suspensions (0.1%w/v). When subjected to alkaline conditions, a pH of at least 12 was needed to significantly increase extractability (up to 77% of all AX). The extractability-increasing effect of alkali was, however, reversible, as extractability decreased again when lowering the pH. Acid hydrolysis at high temperature drastically increased AX extraction yields (up to 97% of all AX), released monomeric arabinose (up to 38%), and lowered the average degree of polymerisation (DPavg) of the AX (down to 31). The presence of substituents (arabinose, xylose, rhamnose and galacturonic acid) on the xylan backbone was an important factor limiting degradation by xylanases. Enzyme preparations containing substituent-removing enzymes were far better for enhancing the extractability of a large portion of the AX population (up to 82%) and for degrading the extracted fragments (down to DPavg 14) than preparations lacking such activities. The above results show that PSH is a good source for the production of AXOS, since both chemical and enzymic treatments significantly increase the extractability of PSH AX and convert PSH AX molecules into small fragments. [Copyright &y& Elsevier]

Abstract: We present characterisation data for two Spanish autochthonous grapevines, Bobal and Crujidera, in comparison with the well-known cultivars Tempranillo and Cabernet Sauvignon. Microsatellite markers were used for the molecular characterisation of Crujidera grapevines. Leaf macronutrient contents of the four cultivars were evaluated, as well as their changes at different vine developmental stages, and veraison was seen as the most suitable time to evaluate the nutritional status. Quantitative changes in some physiological parameters and the phenolic composition of the four grape varieties were measured during the last month of ripening. Polyphenols, tannins and anthocyanins increased with grape maturation, although the accumulation of these phenolic compounds and their patterns of evolution varied considerably with the cultivar. The biosynthetic potential of these grapes to produce resveratrol largely depended on the grape variety, with a remarkably high content found in Bobal berry skins. [Copyright &y& Elsevier]

Abstract: The effects of cooking, baking, fermentation and drying on the extractability of β-glucan were studied. The β-glucan was isolated from porridge, bread and fermentate both fresh and dry. Analyses were performed using three hydrolysis methods: acid hydrolysis (AH) with H2SO4, lichenase hydrolysis (LH) and the modified AOAC 995.15 method (MH). As shown by the DP3:DP4 ratio, processing did not affect the structure of soluble β-glucan. Cooking increased the amount of soluble β-glucan but baking decreased it. Thus, cooking appears to be the most favourable process when health effects are concerned. The results of the three methods were compared statistically. The AH and MH methods, which are based on measurement of glucose, gave similar results. LH, which is based on analysis of oligosaccharides, gave higher results than AH and MH. [Copyright &y& Elsevier]

Abstract: Ten pearl millet cultivars (SOSAT C-88, ZANGO, EX-BORNO, LCRI 9701, ICMV-IS 94206, ICMV-IS 94208, GWAGWA, G.I-14.9, GB 8735, G.I-297-1) were germinated for 96 h. The germinated grains were dried, polished and milled. Phytic acid contents and hydrochloric acid (HCl) extractability of minerals from the malt flours were determined at intervals of 24 h during germination. Phytic acid content decreased significantly (P<0.05) with increase in germination time with concomitant increase in HCl extractable mineral contents. EX-BORNO had higher extractable Ca, while LCRI-IC 9701 had higher P, whereas Zn, Cu, Fe and I recorded high levels in ICMV-IS 94208, GB 8735, G.I-297-1 and ICMV-IS 94208, respectively. Mn did not differ (P>0.05) at the various levels of germination time. There was good correlation between phytic acid reduction and increase in extractable minerals with increase in germination time. [Copyright &y& Elsevier]

Carotenoids are associated with proteins in muscle tissues of salmonid fishes. The extractabilities of astaxanthin (3,3′-dihydroxy-β,β-carotene-4,4′-dione) and protein from minced muscle of Atlantic salmon (Salmo salar) were investigated using different brine concentrations (0–6 M) and different pHs (4–8) to discover whether they contribute to poor colouration of salmonid fish muscle. The salmon had been fed a diet, containing 55 mg kg−1 astaxanthin from Xanthophyllomyces dendrorhous, for 12 weeks, and contained 3.9±0.03 mg carotenoids kg−1 muscle. The plot of ratios between extracted astaxanthin and protein was bell-shaped with a maximum at pH 7, and was considerably lower in brine (1–6 M NaCl) than in distilled water. Regardless of the NaCl-concentration, the highest extractabilities of protein and astaxanthin were found at pH 6–7. Extractabilities of protein and astaxanthin were highest for NaCl concentrations of 1–4 M. The total amount of proteins extracted with brine correlated well with extracted astaxanthin (R2=0.82). The amounts of astaxanthin extractable from the mince were in the range 1.6–7.4 and 5.9–21.3% of total carotenoid content, in distilled deionised water and 1.0 M brine, respectively. In conclusion, the use of excess water during dry salting, may dilute salt at the surface and partly contribute to discoloration of salmon products, whereas protein–astaxanthin extraction is expected to be less during injection and brine salting due to the high salt concentration. [Copyright &y& Elsevier]

• Most of seed tannins are extracted at the middle of alcoholic fermentation. • Seed tannins are trapped in wine matrix and progressively release during winemaking. • Wine content seems to be the major factor affecting seed tannins extractability. The extraction of seed and skin tannins in wine has been investigated at three different grape maturity stages. For that, the tannins content and composition of seeds and skins at three different maturity stages were characterized. After that, an original approach of nanovinification was conducted. At each maturity stages, three winemaking modalities have been produced: (i) a control modality, (ii) a seed modality made of exclusively with seed and (iii) a skin modality made of exclusively with skins. The aim of this work is to describe and explain the seed tannins kinetics release in wine but also the impact of grape maturity on seed tannins extractability. For that, the evolution of seed and wine tannins content have been followed during the winemaking, from alcoholic fermentation to post-fermentative maceration. [ABSTRACT FROM AUTHOR]