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关键词： Jabuticaba fermentation   Anthocyanins   Mineral content   Nuclear magnetic resonance analysis   Chemometrics  

摘要： The jabuticaba fermented beverage, or jabuticaba wine, shows certain sensorial properties similar to those of red wine. Here, a comprehensive bromatological analysis of seven artisanal jabuticaba wines (JW1-7) revealed different physicochemical and color properties. Among the samples, JW6 stood out for having the highest content of monomeric anthocyanins (28.8 mg/L) and minerals, such as K (1594.58 mu g/mL) and P (49.89 mu g/mL). Surprisingly, the Cu content found in all samples exceeded the maximum limit established for this metal in wines. Using NMR-based metabolomics, more than 100 compounds were identified, most of them were carbohydrates. Furthermore, a discriminant analysis of the metabolomic data by PCA revealed that the contents of sucrose, glucose, stachyose and quinic acid enabled the differentiation of the wines and wine producers. The results presented here pave the way for further investigations into the composition of jabuticaba wines and their impact on product quality.

关键词： oil sludge   composition   low-frequency acoustic treatment   viscosity   additive   relaxation  

摘要： The effect of complex physicochemical treatment combining low-frequency acoustic action and the use of depressor additives on the composition and viscosity properties of oil sludge was studied. After the complex action, the viscosity of the treated sediments additionally decreased by a factor of 1.5-2, and the thixotropic recovery of properties increased to 72 h. The minimum values of the viscosity of the mixtures of oil sludge with oil correspond to a maximum decrease in the concentration of benzene and alcohol-benzene resin components and an increase in the amount of the oil fraction.

关键词： Fruits  

摘要： Effects of roasting (80 degrees C, 3 and 5 min) and boiling (chestnut to water 1:2 (w/w), 7 and 9 min) pre-treatments and brine ratios (5% and 7%) on physicochemical and bioactive properties of firstly developed chestnut pickles were investigated. Dry matter and total acidity increased by pickling while pH and salt were decreased. Total, reducing sugars and starch of pickles ranged between 2.13-3.53, 0.28-0.45, and 18.61-23.67 g/100 g respectively. L*, b*, C*, and h degrees decreased in comparison to chesnut as a* displayed an increment. The highest phenolics were determined from the pickle produced in 7% brine without any treatments (126.11 mg GAE/100 g dm) while the pickle produced in 7% brine by 5 min roasting had the highest antioxidant capacity (CUPRAC: 14.83, FRAP: 21.38 mu mol TE/g dm). Usage of chestnut as a raw material allowed designing of a sensorially accepted pickle additionally, roasting and salt ratio were concluded as the key factors. Practical applications High-quality chestnuts can be used in various forms such as frozen, sterilized, or dried in gastronomy. On an industrial scale, chestnut is processed into canned products, candies, creams, flour or it can be used as ingredients for biotechnological purposes due to its high starch content. Processing low or good quality chestnuts into alternative end products is an economically profitable way as well as reducing the waste levels from industrial processing while increasing the added value of chestnut products. Thus, by pickle production, chestnut was processed into a nonseasonal shelf life prolonged product for markets for the first time.

关键词： Acceptance   Bovine milk   Dairy products   Low-fat yogurt   Sensory analysis  

摘要： Yogurt is one of the most popular and consumed foods worldwide, being widely used in gastronomy. This work aimed to evaluate how the addition of skim milk powder (SMP) and dairy cream (DC) can influence the fermentative process of milk and the physicochemical and sensory properties of concentrated Greek-style yogurt. The acidification profile of milk was evaluated by the decrease of pH values during the fermentation process. The quality of the yogurts was investigated by physicochemical, microbiological, and sensory analyses. The addition of SMP affected the fermentation process and resulted in yogurts with high protein content (6.38-6.61%) and low-fat content (1.37-1.38%) in relation to T0 (control), which presented 5.96% of proteins and 1.59% of lipids. The elaborated yogurts did not present contamination, demonstrating satisfactory hygienic-sanitary conditions sufficient on the processing which ensure their microbiological quality. The sensory attributes were influenced by the addition of SMP and DC, contributing to the choices made by the panelists. The yogurt with 10% of SMP presented the best contents of protein and lipids and was the most accepted by the panelists in the sensorial tests. Thus, it is possible to obtain high added-value yogurts with physicochemical and nutritional properties, and sensorial acceptance better than traditional yogurts from the concentration and addition of SMP and DC.

关键词： Soy sauce aroma   Daqu   Untargeted metabolomics   Microecological marker   Metabolic pathway  

摘要： Daqu is the starter for making baijiu (Chinese liquor). Daqu impart distinctive flavors to baijiu, but understanding of the metabolite composition and factors affecting fermentation performance of yellow, white and black daqu are limited. In this study, the relationship between the physicochemical properties of daqu and their metabolic profiles was determined. A total of 647 compounds were identified in daqu, including 401 volatile compounds, mainly aromatic compounds and pyrazines, and 246 non-volatile compounds which were mainly organic and amino acids. Correlation analysis showed that liquefying power, saccharifying power and pH were the main physicochemical properties accounted for the differences in metabolic profile between the three types of daqus. A group of 48 biomarkers (mainly alcohols, aromatics and non-volatile organic acids) selected by multivariate statistical analysis, could clearly distinguish between different types of daqu. Different metabolite phenotypes in three types of daqu were mainly caused by 21 metabolic pathways.

关键词： Deep eutectic solvent   Green solvent   Physicochemical properties   Solvent performance   Molecular structure   Functional applications  

摘要： Deep eutectic solvent (DES) is regarded as a new generation of green solvent due to its distinctive and tailorable physicochemical properties, such as low volatility, strong solubility, biodegradability, low-cost, environment-friendly, and feasibility of the structural design. As an alternative to traditional organic solvents and ionic liquids (ILs), DESs have been widely applied in many fields, such as organic chemical synthesis, electrochemical deposition, material preparation, biomass catalytic conversion, extraction and separation, detection and analysis, nanotechnology, gas absorption, and drug delivery. In this paper, through in-depth discussion on factors influencing the physicochemical properties of DESs, we summarized the relations between their composition, structure, and performance. Focusing on their solvent performance, we analyzed the latest research results of DESs with different physicochemical properties in various fields. It should be pointed out that designing and synthesizing DESs from the molecular structure aspect to regulate their physicochemical properties is the direction of accurately developing new functional applications of DESs.

关键词： Type 3 resistant starch   Ultrasound   Enzymolysis debranching   Physicochemical properties   Structure  

摘要： The effects of ultrasound-assisted enzymolysis on the physicochemical properties and structure of arrowheadderived type 3 resistant starch (RS3) were investigated. Compared with the traditional enzymolysis, ultrasonic treatment significantly (p < 0.05) increased the resistant starch yield by 34.46%. Enzymolysis reaction kinetics revealed that ultrasound-assisted enzymolysis remarkably increased the enzymolysis rate and amylose content. After ultrasound treatment, RS3 displayed higher solubility, swelling power, transparency, and water absorption capacity. The results of particle-size distribution, differential scanning calorimetry, X-ray diffraction, Fourier transform-infrared spectroscopy, and scanning electron microscopy analyses demonstrated that RS3 prepared by ultrasound-assisted enzymolysis exhibited a larger granule size, higher crystallinity, a more ordered and stable double helix structure with increased surface roughness compared to those of RS3 prepared by traditional enzymolysis. These findings provide a theoretical background for the preparation of RS3 using an ultrasoundassisted enzymatic method and will promote the development of ultrasound chemistry in starch science and technology.

关键词： chicken   chitosan film   plasma   starch film  

摘要： The aim of this study was to examine mechanical and physical properties of starch/chitosan composite film exposed to low-pressure air and argon plasma at 600 mTorr for different duration (4, 8 and 12 min) and evaluate the shelf life of the chicken breast fillet packaged with plasma-treated films. The mechanical properties of the composite films were improved significantly. It is shown that argon plasma is more efficient in improving the tensile strength of the films and increased it from 10.59 to 22.09 Mpa after 12 min of process due to the formation of a stable cross-linked network on the surface of the polymer, although film's stretchability, modified in air plasma, was significantly more. Solubility and hydrophilicity of the films were increased;however, no significant change in the water vapor transmission rate was observed. Oxygen permeability of films improved after both plasma treatment. Total viable count and oxidative (TBA) changes of fillets were analyzed during shelf life. The results showed that Cold plasma treatment could not prolong the shelf life of the fillets through plasma-treated films.

关键词： By‐   product   dietary fibre   extrusion cooking   rheology   starch digestion  

摘要： In this work, corn extruded snack products were enriched with rice bran (RB) at 10% and 15%. A co-rotating twin-screw extruder was used with a feed moisture content of 16 g 100 g(-1), a screw speed of 240 r.p.m. and four heating sections of the barrel (100, 140, 150 and 150 degrees C). The impact of RB inclusion on nutritional profile, starch digestion, physicochemical and textural properties of snack products was evaluated. RB-enriched extrudates showed a lower specific volume and hardness and higher crispness than control. RB at 15% gave a water-holding capacity lower than control. Rheology of extrudate dispersions indicated an increase in elastic interactions and solid-like behaviour with RB supplementation. Differences in rheological properties resulted in attenuation of predictive glycaemic response for RB-enriched snacks.

关键词： Lignite   Hydrothermal pretreatment   Flotation   Physicochemical characteristics  

摘要： Flotation is the common method for fine low rank coal upgrading while it is always inefficient due to the rough surface morphology and rich oxygen-containing functional groups. Hydrothermal pretreatment is widely used in dewatering for low rank coal. The physicochemical properties of coal surface considerably vary following the hydrothermal pretreatment. In this study, hydrothermal pretreatments at different temperatures for different times were applied to enhance lignite flotation. The hydrothermal pretreatment at 200 ?C can significantly improve the flotation efficiency, while the temperature raised to 300 ?C, the flotation recovery did not increase or even decrease. Scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), Zeta potential, Brunauer?Emmett?Teller, and particle size distribution analysis were conducted to explain the underlying mechanism. The contents of pore and crack on coal surface considerably decreased and more fresh and smooth surfaces exposed following hydrothermal pretreatment, according to SEM analysis. The FTIR spectroscopy and XPS showed that the contents of oxygen-containing functional groups were decreased, while the hydrophobicity of lignite was increased following pretreatment. The decrease of Zeta potential also indicated the decrease of oxygen-containing functional groups and increase of hydrophobicity on coal surface. However, excessive temperature of hydrothermal pretreatment could increase the pore diameter and fine particle fraction, leading to a higher collector consumption and lower bubble?particle collision efficiency. Consequently, the flotation recovery was not improved or even decreased at the hydrothermal pretreatment temperature of 300 ?C. ? 2021 Elsevier B.V. All rights reserved.