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81.
The effects of blanching and drying treatments on stability, physical properties, and antioxidant activity of apple pomace polyphenols were evaluated. Blanched and unblanched apples were extracted, and the pomace was dried in a cabinet dryer at a speed of 3 m/s at 50 °C, 60 °C, 70 °C, and 80 °C. The color, total phenolics, flavonoids, individual polyphenolic compounds, anthocyanins, and total antioxidant activity were analyzed. The blanching process caused a major retention in color, total polyphenolic content, and total flavonoid content for fresh apple pomace when compared with fresh unblanched pomace. Drying of either fresh blanched or fresh unblanched pomace caused a significant reduction (P < 0.05) in total polyphenol and flavonoid content leading to a reduction in the total antioxidant activity. When compared with the unblanched treatment, drying the blanched pomace at 80 °C resulted in a product with significant amounts of total phenolics, flavonoids, and antioxidant activity. The individual phenolic compounds were significantly increased (P < 0.05) in blanched pomace that was not dried when compared with unblanched samples. Drying blanched apple pomace did not cause a significant change in the concentration of individual polyphenolic compounds, but drying unblanched apple pomace caused a reduction in the concentrations of epicatechin and caffeic acid, with an important reduction in p-coumaric acid at temperatures higher than 60 °C. However, the drying process caused a significant reduction in the antioxidant capacity. Therefore, a combination of blanching and drying processes for apple pomace results in a product that maintains antioxidant capacity.  相似文献   
82.
Lactic acid bacteria strains were identified from wheat germ by 16S rRNA partial sequencing, subjected to RAPD-PCR typing and screened. Lactobacillus plantarum LB1 and Lactobacillus rossiae LB5 were used as starters to produce sourdough fermented wheat germ (SFWG). The chemical and nutritional characteristics of SFWG were compared to those of the raw wheat germ (RWG). Lipase activity in SFWG was ca. 2.6-fold lower than that found in RWG. As shown by SPME/GC/MS analysis, most of the volatile compounds derived from lipid oxidation during storage (40 days) were at markedly lower levels in SFWG compared to RWG. Fermentation of wheat germ increased of ca. 50% the concentration of free amino acids. Glu markedly decreased in SFWG, due to its conversion in GABA. The concentration of the anti-nutritional factor raffinose also decreased in SFWG. The in vitro protein digestibility, the concentration of total phenols, phytase and antioxidant activities were increased by fermentation.  相似文献   
83.
Lupin protein is a promising ingredient in functional foods because of its purported hypocholesterolaemic and hypotensive activities. In this study a lupin protein isolate from Lupinus angustifolius was thermally and mechanically treated and the effects on its protein profile were determined. As a preliminary step, the main protein components of L. angustifolius were identified, using the canonical proteomic approach, including 2D-separation and mass spectrometry and, whenever necessary, also “de novo peptide sequencing”. Most of the main spots were assigned to the major lupin storage proteins: α-conglutin, β-conglutin, γ-conglutin, and δ-conglutin. The protein degradation induced by the different treatments was studied via differential scanning calorimetry (DSC), 2D-electrophoresis, and mass spectrometry, in order to get the fingerprint of the intact peptides after processing. The results indicate that, even after harsh industrial processing, α-, β- and δ-conglutin are still able to release stable peptides, although they are completely or partially degraded, as shown by the 2D protein profiles and the DSC graphs.  相似文献   
84.
The paper aims to enlarge the current knowledge about the dependence of technological traits of wheat grain on its degree of infestation (DI) with fusariosis. Samples of grain of four wheat cultivars were obtained from naturally grown crops (control) and from crops inoculated with Fusarium culmorum from which three degrees of kernel infestation were selected. Samples were determined for thousand kernels weight (TKW), total protein, starch and wet gluten (WG) contents, Hagberg falling number (HFN) and sedimentation value (SV). Content of protein and wet gluten showed higher values for moderately infested kernels (up to 15 and 25%, respectively, when compared to control grain) than for kernels lightly or heavily infested. All the remaining traits had values lower than that for control grain and showed a decrease with increasing DI. Decrease for the heaviest infestation was on average: 8, 29, 31 and 34% for starch, TKW, HFN and SV, respectively.  相似文献   
85.
86.
An apple puree formulated with red grape skins was developed on pilot scale as a new beverage with antiglycation properties. The addition level of grape skins was selected by a liking test with 70 consumers. The selected formulation was a fibre‐rich source and delivered grape anthocyanins, flavonols and flavanols resulting in ~ twofold higher antiglycation activity than the apple puree. Pasteurisation (3‐D in the target microorganism Alicyclobacillus acidoterrestris) did not affect the antiglycation activity, which decreased by 30% upon sterilisation. Storage for 1 month in the temperature range 15–35 °C affected the contents of anthocyanins, monomeric, dimeric and oligomeric flavanols, while chlorogenic acid, flavonols and dihydrochalcones were stable. About 90% antiglycation activity was retained after one‐month storage at 15 °C. The use of red grape skin as ingredient could represent an opportunity for the apple processing industry to develop a value‐added product.  相似文献   
87.
This study monitors variations in isotopes and elements in relation to grape variety, environmental factors and provenance in order to address the wine authenticity issue. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) assessed the wines’ elemental content. Site-specific nuclear isotope fractionation-nuclear magnetic resonance and isotope ratio mass spectrometry methodologies determined in authentic and commercial wines the distribution of the naturally occurring stable isotopes of the deuterium/hydrogen (D/H) ratios and carbon (13C/12C) in ethanol of wine and oxygen ratio (18O/16O) in wine water. Chemometrics delineated the elements and isotopes responsible for wine classification. Specifically, unsupervised principal component analysis (PCA) framed the importance of grape variety and provenance, while supervised analysis pinpointed the vineyard effect and highlighted the contribution of the vintage year. Validation steps ensured that the extracted models do not predict randomly and their results are reliable. In fact, the acquired results can be incorporated to the EU Wine Isotopic Databank database providing both a guide and a tool for eventual candidatures for denomination of origin and support both Cypriot wine and winemakers. In this context, this research contributes to authenticity assurance of wines and adds value to final products, while it helps controlling hazards arising from environmental changes.  相似文献   
88.
The aim of this research was to prepare an extruded snack based on nixtamalized maize flour (Zea mays L.) (NMF) enriched with grasshopper meal (Sphenarium purpurascens Ch.) (GM) using a single screw extruder with a compression screw ratio of 3:1. A central experimental design comprising three independent variables, namely, extrusion temperature (T = 120–180 °C), feed moisture content (FMC = 18–22 g/100 g) and the grasshopper meal proportion (GMP = 0–40 g/100 g), was used. Increasing T decreased (P < 0.05) the expansion index (EI), bulk density (BD) and hardness (H). Increasing the FMC increased (P < 0.05) the EI. Increasing the GMP decreased (P < 0.05) the EI, H and water absorption index (WAI) and increased (P < 0.05) the BD and total colour difference (ΔE). The treatments that resulted in better general acceptability were those that contained a lower GMP. An extruded snack acceptable to the consumer can be obtained from a blend of NMF and GM, and up to 8.11 g/100 g of GM can be incorporated without affecting the physicochemical properties and acceptance of the snack.  相似文献   
89.
Recent and past food scandals highlight the urgent need for food safety authorities to anticipate future risks in order to enable improved and proactive response mechanisms. With this goal in mind, the Bavarian Health and Food Safety Authority (LGL) has established an early warning system aimed at early identification of potential health risks and fraudulent practices in the food sector. The early warning approach allows intervention at different stages of risk development. On the one hand, the scanning of a broad area of the food production chain (horizon scanning) may enable prospective risk identification. To this end, relevant factors of influence (drivers) need to be identified, observed and analyzed. On the other hand, the retrospective analysis of case studies may unravel novel cause-effect associations that could be transferred to other products and production technologies, possibly leading to the identification of new drivers (root cause analysis). Additionally, various datasets emanating from food safety authorities, for example data from the European Rapid Alert System for Food and Feed (RASFF) and from Bavarian-wide laboratory analyses and food business inspections, will be closely observed and analyzed. The multidisciplinary character of the LGL has proven to be essential for the realization of the early warning approach, the analysis of inflowing data and implementation of consequences such as food business inspections and sampling for analysis. This article details the objectives and methodical approaches of the project. The acquisition of systematically compiled information as well as its analysis and assessment are comprehensively described. The early warning system presented here has already contributed significantly to the risk-oriented food inspection practiced to date, by integrating novel risk-relevant aspects.  相似文献   
90.
Twenty-six plasticisers and bisphenol A (BPA) in 39 Sicilian and Calabrian nectar honeys of different botanical south Italian origin were determined by GC-MS. Di-(2-ethylhexyl)phthalate was the most abundant plasticiser in all samples, reaching up 202.7 ± 153.1 µg kg–1, followed by di-butylphthalate with a concentration of 40.3 ± 9.3 µg kg–1, whereas the concentration of the other phthalates varied from not detectable to 68.2 µg kg–1. Trace levels of adipate, sebacate and BPA were not detected in any samples. Among the different floral origin honeys, di-ethylphthalate levels were above the limit of quantification (LOQ) in orange blossom, wildflower and chestnut honey samples. Among the honeys of different geographical origin, di-methylphthalate, di-butylphthalate and di-(2-ethylhexyl)phthalate concentrations were similar. Calabrian honeys showed levels of di-ethylphthalate always lower than the LOQ, moreover di-(2-methylpropyl)phthalate levels were lower than the Sicilian ones. On the contrary, in Sicilian honeys di-(2-methylpropyl)phthalate levels were higher and di-ethylphthalate was present in 37% of samples.  相似文献   
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