1,720,975 research outputs found
Effect on quality and safety of hydrophilic reducing compounds integration into taralli via wine enrichment
No full textTaralli undergo thermal stress during cooking that can trigger oxidation and acrylamide (AA) production. Natural reducing compounds, like antioxidants, can mitigate the thermal damage and safeguard taralli quality. Hence, the use of a fortified white wine in the taralli recipe, enriched by direct contact with vine shoots, was tested. Firstly, the fortification step was studied by a design of experiment (DoE) methodology. The results showed that a vine shoots/wine ratio of 1:5 and 5 min of sonication caused a marked improvement of wine total hydrophilic reducing compounds (THRC) and antioxidant activity. Following, the enriched wine was used in taralli production in comparison with a control. THRC, antioxidant activity, and oxidative stability significantly increased in taralli when the fortified wine was used, while the AA level was lowered by around 40% respect to the control. Fortified taralli were slightly darker and harder than the control ones, but their organoleptic traits were found to be almost similar
An Overview of the Purity Characteristics, Pigments, and Tocopherol Contents of 48 Virgin Olive Oils from Apulian Minor Olive Accessions
Full text linkTogether with the most diffused olive cultivars used for virgin olive oil (VOO) extraction, Apulia boasts a plethora of other minor varieties and accessions whose oil characteristics is little or no studied at all. The main novelty of this study is then providing new insights about selected characteristics of 48 VOOs extracted from underexplored Apulian olive accessions. VOOs were extracted at laboratory scale and characterized for their fatty acid and sterol composition, pigments, and total tocopherol contents. Moreover, multivariate approaches were used to study VOOs similarity based on purity criteria. The results show that some VOOs had percentages of specific fatty acids or sterols out of current international limits. This was already observed in previous studies and should be taken into account by regulatory bodies and policy makers. The multivariate analysis of the dataset by PCA and k-means clustering allow to identify the VOO from San Benedetto variety as the most peculiar and, on the whole, a total of five different clusters of samples. Pigments and tocopherols ranges are wide among the oils, highlighting possible candidates for further valorization
Feasibility of excitation‐emission fluorescence spectroscopy in tandem with chemometrics for quantitation of trans‐resveratrol in vine‐shoot ethanolic extracts
Full text linkBACKGROUND: trans-Resveratrol (TR) is a well-known phytochemical compound with important biological properties. It can be recovered from agri-food by-products or wastes, such as vine shoots. Once recovered, its concentration should be measured, possibly in a green, non-destructive, and efficient manner. With these premises, this work aimed to explore the feasibility of excitation-emission fluorescence spectroscopy combined with chemometrics for the analysis of TR in raw extracts obtained from vine shoots. A total of 75 extracts were produced and analyzed by ultra-performance liquid chromatography method with diode array detection (UPLC-DAD) and spectrofluorimetry. Then, the feasibility of two calibration strategies for TR quantitation was assessed - a parallel factor analysis (PARAFAC)-based calibration and the N-way partial least squares (NPLS) regression. RESULTS: The extracts showed variable TR content, the excitation/emission maxima of which were at around 305/390 nm, respectively. The best PARAFAC-based calibration allowed a root mean square error of prediction (RMSEP) of 22.57 mg L-1, and a relative prediction deviation (RPD) of 2.91 to be obtained but a large number of PARAFAC components should be considered to improve the predictions. The results of the NPLS regression were slightly better, with a RMSEP of 19.47 mg L-1, and an RPD of 3.33 in the best case. CONCLUSION: Fluorescence could be an alternative analytical technique to measure TR in complex samples. Chemometric tools allowed the identification of the TR signal in the fluorescence landscapes, which could be further used for its non-destructive quantitation. The need for a more accurate criterion for optimal PARAFAC complexity emerged. (c) 2024 Society of Chemical Industry
Influenza dei parametri di regolazione del decanter su efficienza di estrazione, consumi energetici e qualità degli oli extra vergini di oliva
No full textNutritional, rheological, and sensory effect of oat okara enrichment in plant-based ice cream
No full textThe use of agri-food by-products as novel ingredients has gained attention for developing functional foods. This study investigated the effect of non-dairy ice creams fortified with oat okara (OK) at different concentrations (6 %, 12 %, and 15 %), compared to a control (CTR), through proximate composition, rheological measurements (flow behavior and viscosity), in vitro glycemic index, simulated fecal microbiota, sensory analysis. OK6, OK12, and OK15 showed significantly higher dietary fiber (up to 6 g/100 g already in OK6) and protein content (up to 7.70 g/100 g in OK15), meeting the claims for “high fiber” and “source of protein”, respectively (Regulation (EC) No. 1924/2006). Rheological analysis revealed enhanced viscosity, consistency, and thixotropy in enriched OK samples, due to the water-holding capacity of fibers and the structuring effect of residual oat proteins. Specifically, OK12 reached a significant increase of viscosity (0.88) and thixotropy (30.46) compared to CTR (0.21 and 17.77, respectively). Furthermore, OK12 and OK15 displayed a significant reduction (67.36 % and 64.49 %, respectively) of predicted glycemic index (pGI) compared to CTR (76.43 %). Although no significant differences in prebiotic activity were shown between CTR and OK-enriched samples, all ice creams promoted the growth of beneficial bacteria compared to the baseline (T0), suggesting a prebiotic potential
Use of olive leaf extract to reduce lipid oxidation of baked snacks
No full textOlive leaves are a waste of the olive oil processing industry and represent a good source of phenolic compounds. The aim of this work was to assess the influence of olive leaf extract (OLE) on lipid oxidation of baked snacks, like breadsticks, made with wheat flour, extra virgin olive oil (EVO), white wine, and salt. Two EVOs having different peroxide value and antioxidant profile (total phenol content, tocopherols, carotenoids, and antioxidant activity) were considered. The snacks were subjected to oven test or stored in the usual conditions of retailer shelves. The obtained data highlighted that EVO plays a key role both for the quality and for the shelf-life of baked snacks and the use of OLE is recommended especially when baked snacks are produced with low quality EVO which therefore does not have a good content of natural antioxidants. The OLE addition significantly reduced the forced oxidative degradation during oven test, as evidenced by a decrease of 27% in oxidation-related volatile compounds and of 42% in triacylglycerol oligopolymers compared to control snacks (CTR) without OLE. Moreover, OLE effectively acted also in normal storage conditions, improving sensory data, induction times, antioxidant activity, and volatile compounds compared to CTR (i.e. hexanal 165.49 vs 38.31 μg g−1in OLE-added). The amount of oxidation-related volatile compounds showed an opposite trend with the quality level of oil used
Green extracts from Coratina olive cultivar leaves: Antioxidant characterization and biological activity
Full text linkOlive leaves and their extracts are associated with food preservation and health, and are used in folk medicine to treat several diseases, mainly because of their polyphenols. In this investigation polyphenols were extracted from olive leaves using green solvents and evaluated the antioxidant activity of the extracts. Polyphenols were extracted from fresh, freeze-dried, and hot air-dried leaves using either ethanol/water mixtures (70:30, 30:70, v/v) or water alone. Antioxidant activity was assessed in bronchial epithelial NCI-H292 cells by measuring reactive oxygen species (ROS) and in vegetable oil by measuring oxygen consumption. Results showed that extracts with a good antioxidant activity could be obtained when leaves were pre-treated by hot air-drying. The use of water alone as the extraction solvent gave results comparable to those obtained with ethanol/water (30:70, v/v). These extracts were particularly rich in oleuropein, and had anti-ROS effects in NCI-H292 cells and antioxidant activity in vegetable oil
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