查看更多>>摘要：Moutai town is the birthplace and core producing region of Jiang-flavoured Baijiu (Moutai-flavour liquor). The unique climate conditions have made Moutai town a unique ecological environment for the production of Baijiu. We investigated the impacts of environmental factors (temperature, humidity, precipitation, sunlight and pressure) on the environmental bacterial diversity and composition across the four seasons in Moutai town. The sequenceing analysis revealed 21,424-85,577 high-quality 16S rRNA sequences were obtained from 28 environmental samples (a total of 476 samples were collected). These data indicated that the bacterial community was extremely diverse with Proteobacteria, Firmicutes, Bacteroidetes and Actinobacteria detected as the dominant environmental bacterial phyla, accounting for 99.51%. There were 8 dominant bacteria classes present amongst which Betaproteobacteria (1.83%-2.52%) and Flavobacterium (4.76%-5.74%) were for the first time identified as the dominant bacteria in Baijiu-making environments. There were 16 dominant bacterial genera (Sphingobacterium, Enterobacter, Acinetobacter, Weissella and Bacillus, etc) in the four seasons, that accounted for 54.26%. Our results also showed that the environmental bacterial community structure was relatively stable whilst bacterial diversity was related to the climate conditions. We showed that changes in environmental factors, including temperature, humidity and sunlight significantly affected bacterial diversity and composition particularly on the dominant bacterial community.
查看更多>>摘要：Soybean oil emulsion gel is often used to replace part of fat, thereby the content of saturated fatty acids was reduced in food. This paper studied the effect of flax gum (FG) on the rheological properties, thermal properties, microstructure, and gel properties of soy protein isolate (SPI) acid-induced emulsion gels. The results showed that the apparent viscosity of SPI emulsion increased with the increase of FG addition. The mechanical properties, frequency dependence and deformation resistance of the SPI emulsion gel can be significantly improved by adding an appropriate amount of FG (0.6%). The chemical stability of the protein was significantly enhanced, the thermal stability of the emulsion gel was improved, and the water retention rate of the emulsion gel was increased by adding a certain amount of FG. The study also found that the pores between the protein network were increased and the fractal dimension of the gel system (2.862-2.775) was reduced by adding FG. When the FG concentration was 0.8%, the complexity of the gel system was minimal. In summary, FG was found to play an important role in improving the properties of Emulsion Gel, enhancing thermal stability and enhancing the strength of the gel network structure in the soy protein isolate-FG gel system.
查看更多>>摘要：Rice bran is the primary by-products of rice milling, and presents high nutritional values. However, the unavoidable occurrence of rice bran rancidity will cause protein oxidation, and impact the protein structure and functionality. The aim of this study is to evaluate the changes in oxidation parameters, structure and functionality of rice bran glutelin during rice bran rancidity. The results indicated the prolongation of rice bran storage time caused the formation of carbonyl groups (from 2.31 to 19.50 nmol/mg) and the loss of sulfhydryl groups (free sulfhydryl groups from 7.66 to 2.16 nmol/mg, and total sulfhydryl groups from 54.88 to 38.76 nmol/mg). The increasing storage time also strengthened the aggregation and cross-linking of rice bran glutelin. The FT-IR spectra implied rice bran rancidity led glutelin to form more complex secondary structure. As rice bran was stored for 1 day, the solubility, water holding capacity, emulsion stability and foam stability raised, and then decreased with the storage time further prolonged. The correlation analysis showed the oxidation parameters, the alpha-helix/beta-sheet ratio and surface hydrophobicity were significantly correlated to the functionality of rice bran glutelin.
查看更多>>摘要：This study investigated the effects of fish mince size on the gelling properties of silver carp surimi gel produced by microwave heating combined with the water bath method. As the mince size increased, the mince protein and fat contents increased, but the moisture content decreased. Although the strength and water holding capacity of the surimi gel obtained from the larger mince were lower, the detrimental effect resulting from this larger size was considerably reduced by microwave heating; this afforded the fast and selective heating of the heterogeneous surimi. A soft textured compact gel structure was obtained from the 4 mm fish mince based on the results of the texture profile analysis and scanning electron microscopy. These results are anticipated to aid in the formulation of a method for reducing the loss in the processing of muscle fibers to realize the accurate and moderate processing of low-value fish.
查看更多>>摘要：Lipid and protein oxidation always causes the deterioration of foods and their shortened shelf lives. The aim of the present work was to evaluate the effect of high-intensity ultrasound on the chemical and physical stabilities of oil-in-water emulsions comprising a plant-based oil (walnut oil) and protein (almond protein isolate). Emulsions were produced using a three-step procedure: high-shear mixing, sonication, and homogenization. The sonication step was carried out for 30 min at three different energy densities: 0, 200, or 400 J/cm3. Increasing sonic energy densities resulted in much smaller particle size and more droplet charge of the freshly made emulsions. The sonication step also improved the physical stability of emulsified lipids during storage by suppressing the changes in the droplet size and charge. Meanwhile, sonication also inhibited the oxidation of emulsified lipids by decreasing the generation of lipid hydroperoxides and 2-thiobarbituric acid-reactive substances as well as protein by reducing the gain of carbonyls, the loss of free sulfhydryl groups and intrinsic tryptophan fluorescence, and the modification of molecular weights. The highest sonication energy density (400 J/cm3) gave the best results. This study is expected to broaden the application of high-intensity ultrasound in protein emulsion production to improve their quality and acceptability.
Pamies, Laura Cecilia GomezRovaletti, Maria Mercedes LatazaAmezaga, Nancy Maria Jimena MartinezBenitez, Elisa Ines...
9页
查看更多>>摘要：The traditional sorghum beer brewed by African communities differs from the traditional beer obtained from barley, mainly in the absence of hops and in a higher acidity level. People diagnosed with celiac disease find it as an alternative option when enjoying a good beer; however, some of the technological differences could be improved with the use of pyrodextrins obtained from the same cereal. In this work the use of pyrodextrins obtained by a treatment at 120 degrees C with acid during 360 min is proposed. A composite central design was made varying the concentration of pyrodextrins between 5 and 15 g/L and hop between 30 and 60 mg/L. The results indicate that the use of pyrodextrins up to a concentration of 10 g/L improves alpha-acid utilisation, bitterness and viscosity of the drink, achieving values similar to a typical lager beer obtained from barley. For 10 g/L pyrodextrin addition the increase in the wort and beer viscosity was 4.4% and 4.9%, respectively.
查看更多>>摘要：Increasingly attention has been paid to the active substances in grapefruit peel. In this study, insoluble bound phenolic compounds (BP) were released from grapefruit peel insoluble dietary fiber (GP-IDF) by microwave extraction (M-BP), enzymatic hydrolysis (E-BP) and combined microwave and enzymatic treatment (ME-BP). The results showed that the yield of ME-BP was the highest (148.856 +/- 0.620 GAE mg/100 g), and conditions of microwave treatment (microwave power, temperature, time) were 600 W, 85 degrees C, and 37 min, while that of enzymatic treatment were 8% addition, 60 degrees C, and 2 h. Scanning electron microscopy displayed that GP-IDF became looser by ME. ME mainly resulted in the removal of lignin in IDF from X-ray diffraction, which was consistent with FT-IR. Twenty seven BP were identified by UPLC-ESI-QTOF-MS/MS. The high content of gallic acid (42.50 + 3.21 mu g/g DW), ferulic acid (18.46 +/- 1.65 mu g/g DW) and protocatechuic acid (6.16 + 0.72 mu g/g DW) was quantified by LC-ESI-QqQ-MS/MS. Furthermore, ME-BP showed stronger antioxidant capacities than that of others (ABTS, oxygen and DPPH free radical scavenging ability), and showed good inhibition of alpha-glucosidase. Our results demonstrated that combined microwave and enzymatic treatment was an effective treatment for improving the release of BP.
de Andrade, Aurora Brittoda Cruz, Margarida LinsOliveira, Fernanda Antonia de SouzaSoares, Sergio Eduardo...
11页
查看更多>>摘要：Under-fermented cocoa mass (UCM) presents, as well as the fresh cocoa seed, a high content of phenolics compounds. For this reason, a chocolate with UCM added to the fermented cocoa mass (FCM) was developed. The sensory quality of chocolate is broadly determined by the composition of volatile compounds resulted from microbial metabolism during fermentation and Maillard reactions, that occur during drying, roasting, and conching. The aim of this work was to investigate the effect of adding UCM (20%-80%) to the FCM on the sensory characteristics of the chocolates produced and their volatile profiles during the process chain. The UCM and FCM were obtained through fermentation (48 h and 144 h, respectively), drying, roasting, and grinding processes. In general, the chocolate samples with a higher content of UCM presented lower scores for flavor acceptance, due to their higher bitterness and astringency. The great acceptance was observed on samples with 80% and 65% of FCM. A total of 55 different volatile compounds were identified by HS-SPME-GC-MS. The PCA analyses showed that the profile of the volatile compounds in the chocolate samples was influenced by the fermentation process, as well as the chocolate quality (flowery, honey, fruit, roasted, and chocolate flavors).
查看更多>>摘要：The effects of ultrasound (US) pretreatment on natural structure modification from broccoli were investigated, and the influences of the modification on the bioaccessibility and cellular uptake efficiency of bioactive compounds were analyzed. US treated broccoli showed significant cell wall and cellular matrix degradation, which could be mainly responsible for the release of bioactive compounds from broccoli cells. Data from digested broccoli fractions showed that US pretreatment resulted in decrease of viscosity of the digesta, which could be partially responsible for the release of bioactive compounds from the digesta into the supernatant. High bioaccessibility of bioactive compounds appeared to be somewhat a similar high cellular uptake. The reduction of the particle size upon US pretreatment might be contributed to the increased carotenoid cellular uptake. These data indicated that US pretreatment may be considered as a potential processing method for improving the bioavailability of bioactive compounds.
查看更多>>摘要：Sustainable, bio-based emulsifications stored as dry particles and conveniently converted to edible re-dispersible emulsions are of increasing interest in the food, cosmetics, and pharmaceuticals industries. Dried sunflower oil emulsions (98 g/100 g) oil content that are conveniently re-dispersible, were prepared from a complex of regenerated chitin (RCh) and hydroxypropyl methylcellulose (K100M) via Pickering emulsion. The concentration of RCh and K100M (0.25-1.0 g/100 g) on the formulation of emulsions droplets, stability, and viscoelastic properties were investigated. The results showed the emulsion droplets decreased with the increasing concentration of RCh and K100M, which led to an increase in the emulsion stability. The emulsions prepared dried without oil leakage and were easily redispersible after the freeze or oven-drying. Compared to the freshly prepared emulsions before drying, the re-dispersed emulsions from freeze-/oven-drying consisted of similar symmetrically spherical-shaped droplets with a slight increase in size. The marked stability of such emulsions was attributed to highly networked RCh systems both for fresh and re-dispersed emulsions confirmed by results of rheology and long-term stability. Therefore, such dried edible emulsions containing sustainable, bio-based RCh/ K100M emulsifiers have a significant potential for many applications.
NSTL
Elsevier