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关键词： Physicochemical properties  

摘要： Thirty experimental Xuanwei hams were processed by a traditional method using green hams from local Xuanhe pigs of Xuanwei, Yunnan province, PR China. Samples of Biceps femoris were collected from six hams randomly at the five key processing stages, that is green ham, salting, air drying, aging for 3 months, and aging for 7 months. Physicochemical properties and water-soluble small molecular (WSSM) compounds change during the processing period of Xuanwei ham were evaluated. Moisture contents, water activity, and total nitrogen contents (TN) decreased significantly (p < .05). On the contrary, chloride content, weight loss rate, non-protein nitrogen content (NPN), and the protein hydrolysis index (P.I.) were observed a significant increase during the processing. The WSSM compounds in various processing stages of Xuanwei ham were analyzed by proton nuclear magnetic resonance (H-1-NMR) technology. A total of 54 WSSM compounds were found, consisting of 26 amino acids and their derivatives, 10 organic acids, 6 nucleic acids, 4 amines and ammonia compounds, 3 alcohols, 2 sugars, and 3 other WSSM compounds. After aging for 7 months, the content of free amino acids in hams reached 58.93 mg/g, and the main amino acids were glutamic acid and alanine. In this study, the physicochemical properties of Xuanwei ham were evaluated effectively, which provided the basis for the quality control of Xuanwei ham. Practical applications Dry-cured Xuanwei ham is a traditional fermented meat product in Yunnan province of southwest China. The aim of this study was to determine the changes in physicochemical properties and water-soluble low molecular weight compounds of dry-cured Xuanwei ham during the production process. Our findings thus provide a theoretical analysis on the quality changes of dry-cured Chinese Xuanwei ham during processing. The results of this study can provide important theoretical basis for further study on protein degradation mechanism and characteristic flavor formation

关键词： Cellulose  

摘要： Fresh corn bracts were used as raw materials to prepare dietary fiber, dynamic high-pressure microfluidization technology (DHPM) was then conducted to modify the fresh corn bract insoluble dietary fiber (FCBIDF) to explore its effect on the physiochemical properties and structural characteristics of FCBIDF. Results showed that in the pressure range of 80-180 MPa, the water-holding capacity, water-swelling capacity, and oil-holding capacity of the dietary fiber of fresh corn bracts treated by DHPM significantly increased. When the DHPM pressure was 180 MPa, compared with the untreated group, they increased by 75.56%, 118.04%, and 78.58%, respectively. The particle size for FCBIDF treated by DHPM obviously reduced. The SEM images of the sample showed the loosened surface structure, the honeycomb-like porous feature appeared. Differential scanning calorimetry analysis demonstrated the enthalpy value of FCBIDF significantly reduced, and its thermal stability destroyed. XRD and FTIR analyses indicated the relative crystallinity of FCBIDF declined and some cellulose components redistributed and transformed into soluble dietary fiber. Those results provided a useful reference for physically modifying insoluble dietary fiber and increasing the added value of fresh corn bracts. Novelty impact statement Dynamic high-pressure microfluidization (DHPM) technology improved the water-holding capacity, water-swelling capacity, and oil-holding capacity of fresh corn bract insoluble dietary fiber (FCBIDF). The surface of FCBIDF treated by DHPM appeared holes and cracks, and the particle size decreased. The relative crystallinity of FCBIDF declined and some cellulose components redistributed and transformed into soluble dietary fiber after DHPM.

关键词： Yogurt drink   PLLA   Physico-chemical   Coliform colony   Spoilage indicator  

摘要： This study aims to determine the yogurt drink spoilage profiles and its physico-chemical properties correlation as to investigate the coliform potability level upon exposure to an open air (unsealed condition). The commercially available three induced contamination of fruit (berry) flavoured yogurt drinks (labelled as A0 (original-flavoured Farm Fresh (TM)), A1 (Farm Fresh (TM)), A2 (Marigold (TM)) and A3 (Nestle (R))) were created to pre-run a spoilage indicator model system with regards to the colony formation unit (cfu) and its physico-chemical properties. Physio-chemical analysis (e.g., Brix, pH, colour and contact angle) and microbiological analysis were performed at 30 min intermittently for up to 4.5 h as soon as the food sample was unsealed (room environment condition: 27 +/- 2 degrees C;relative humidity (RH): 73 +/- 1%). The results showed the presence of yeast and fungus in yogurt drinks after all samples were opened and exposed to the environment. The total formation of yeast colonies and fungi of all three-yogurt berry drink brands on DRBC agar were inevitably high during the treatment (p< 0.05). The amount of cfu/ml of yeast and fungus was higher than the total coliform colony (Escherichia coli) formed throughout the sampling period. The pH analysis showed a significant decrease throughout the treatment due to the accumulation of lactic acid which resulted in high acidity (p < 0.05). The colour profiles of A1 brand showed a significant improvement as compared to A2 brand due to the increasing redundancy degree (p < 0.05). However, the A3 brand has a significant low reduction value, which is the degree of yellowness due to the microorganism's contamination. Finally, the contact angle analysis at 0:00-3:00 h, the range of contact angle of A1 (exclusively selected due to highly pathogenic spoilage) was 45.34-42.80 degrees while at 3:30-4:30 h was 58.66-61.12 degrees with diameter 0.9 and 0.7 cm respectively. In conclusion, the presence of yeast and mould

关键词： Ginkgo seed protein isolate   Pectin   Gelling properties   Degree of esterification  

摘要： In this study, we investigated the effects of pectin concentrations and degrees of esterification (DE) on the gelling properties of ginkgo seed protein isolate (GSPI) ? pectin composite gels. The composite gels were formed by heating a mixture of 12% (w/v) GSPI and pectin (0, 0.1, 0.5, and 1.0% w/v) of different DE (38%, 60%, 76%) at 90 ?C, pH 6.0 for 30 min. The addition of pectin increased the apparent viscosity and charge density of the sols while decreased the particle size. Rheological and textural properties of the gels were enhanced by 0.1% and 0.5% of pectin, while 1.0% of pectin led to a poor gel texture, as well as lowed water holding capacity. Changes in gel microstructure were observed when pectins were added. Hydrogen bonds played an important role in gel formation. The addition of low-methoxyl pectin (DE = 38%) with high charge density resulted in superior gelling properties. We demonstrated the potential of a GSPI-pectin composite gel with controllable gelling properties by adjusting the concentration and DE of the pectin.

关键词： Argan fruit residues   Physicochemical analysis   Thermal analysis   Ignition temperature   Thermal conductivity  

摘要： A detailed investigation of the physicochemical properties and thermal characteristics of argan fruit residues (AFRs) was carried out to identify their potential application as biofuels. This experimental study covered the four main by-products of argan fruit: argan pulp (AP), argan nut shell (ANS), argan oilcake (AOC) and argan deoiled cake (ADC). Physicochemical analysis was performed to characterize biomass-based materials. Thermogravimetric techniques (TG, DTG and DTA) were applied to assess structural decomposition, biomass reactivity and combustion parameters. Lastly, thermal conductivity and diffusivity between 25 and 100 degrees C were measured using the transient plane source technique (TPS). The study shows that heating values were in the range of 17-22.5 MJ kg(-1), which is comparable to those of wood pellets and lignite coal. The maximum ash content was found in AP and the minimum in ANS. The residual oil of AOC was found to affect the drying process and calorific value. Thermal analysis showed that ANS has the highest ignition temperature and thermal conductivity values and therefore appears to be the most reactive material. Our data show that ANS has a good potential to produce heat through direct combustion. A pretreatment appears to be necessary to improve the characteristics of AP and AOC in order to make them suitable biofuels in the near future.

关键词： Aminopeptidase B   Metalloprotease   Lactic acid bacteria   Pediococcus acidilactici NCDC 252   Probiotic  

摘要： An arginine aminopeptidase (EC 3.***.11.6) called aminopeptidase B was purified to apparent homogeneity from membrane extract of a potential probiotic Pediococcus acidilactici NCDC 252 using successive chromatographies on sephadex G-100 and phenylsepharose CL-4B. Purified enzyme was a heterotrimer with molecular mass of similar to 101.36 kDa. Predicted molecular weight of the enzyme from its gene (93.9 kDa) was close to the calculated molecular weight. The enzyme was optimally active at pH 7.5 and 40 degrees C. It was strongly inhibited by metal chelating agent and thiol protease inhibitors suggesting that enzyme is a metalloprotease with involvement of thiol. The K-m and V-max of enzyme for Arg-4m beta NA were calculated to be 26 mu M and 19.9 nmol/ml/min respectively. Its 3-D structure was modeled and validated using in-silico approach. In-silico analysis revealed Ser, His, Phe, Tyr and Thr to be present at active site of aminopeptidase B. Docking studies revealed that Arg-4m beta NA binds with high affinity to the enzyme followed by Lys-4m beta NA. The enzyme also hydrolyzed dipeptide-4m beta NA derivatives containing hydrophobic amino acids and diaminocarboxylic acids (Arg, Lys and Asp) at the N-termini but not tripeptides, endopeptidase substrates and -beta NA derivatives or peptides with proline and phenyl at their N-termini or C-termini.

关键词： Oilseeds  

摘要： There is increasing interest in the blending of edible vegetable oils containing essential fatty acids and natural vitamins. The present study aims to develop spray-dried microencapsulates of a blend of red palm oil and flaxseed oil. The wall material composition and inlet temperature of spray drying were varied to maximize the encapsulation efficiency. Among the different trials, maximum encapsulation efficiency was achieved at a core-to-wall ratio of 1:2, an oil payload of 34%, and an inlet temperature of 180 degrees C. The encapsulates were characterized for water activity, bulk density, particle morphology, carotene content, and encapsulation efficiency. To evaluate the potential of spray-dried oil encapsulate as a fat replacer, it was incorporated in cupcake formulation at 40% replacement of butter. The spray-dried oil encapsulates retained more than 70% of beta-carotene. Even at a higher oil payload, the spray-dried microcapsules showed good flowability and low moisture content (2.60%). The test cupcake met 36.87% of the recommended dietary allowance for beta-carotene. Thus, this study established the potential of spray-dried oil microcapsules as a fat replacer and beta-carotene fortificant in cupcakes. Practical applications The blending of edible oils is considered the least expensive approach for attaining the balanced fatty acid composition. Encapsulation increases the shelf life and protects the core component. Red palm oil (RPO) is a minimally processed oil that retains most natural carotenoids, and flaxseed oil (FSO) is rich in its unsaturated fatty acid composition. Thus, the present study aims to use the RPO-FSO encapsulate as a beta-carotene fortificant.

关键词： DNA metabarcoding   Community composition   Ectomycorrhizal fungi   Saprotrophic fungi   Fungal diversity   pH   N   P  

摘要： Soil fungi are fundamental drivers of forest ecosystem processes. Soil physico-chemical parameters and vegetation features such as host type or stand structure can affect soil fungal communities. However, there is a lack of comprehensive studies describing the relative importance of niche processes (soil physico-chemistry and forest structural drivers) versus neutral processes (geographical distance) driving soil fungal community assemblages, especially in less-studied drought-prone ecosystems such as Mediterranean forests. In this study, we performed Pacific Biosciences sequencing of internal transcribed spacer 2 amplicons to characterize the soil fungal community composition and diversity of 42 forests dominated by either pure Pinus nigra, Pinus halepensis or Pinus sylvestris or a P. nigra-P. halepensis or P. nigra-P. sylvestris mixture. Our specific aims were to identify and disentangle the relative importance of the main soil characteristics and the spatial and forest structural factors that accounted for the greatest proportion of fungal community variation along a regional gradient in the Mediterranean Pre-Pyrenees. Soil parameters accounted for the greatest significant proportion of the total variance in the overall fungal community (25%), in the mycorrhizal (23%) and saprotrophic (22%) communities, while geographical distance accounted for 14% of the variance in the overall fungal community, 7% in the mycorrhizal and 22% in the saprotrophic communities. Conversely, forest structure did not significantly affect the soil fungal community, as fungal composition and diversity did not differ significantly among the pine hosts. Moreover, pH, followed by P and the C:N ratio explained the largest differences in the composition of the overall fungal community and in the mycorrhizal fungal community. By contrast, the largest proportion of differences in saprotrophic composition were explained by geographical distance, closely followed by the C:N ratio and N. Our resul

关键词： By-products   Protein oxidation   Ultrasound treatment   Fibre   Texture  

摘要： As a result of agri-food production, large quantities of organic waste are produced in the form of press cakes (by-products of plant-based drink production), and a huge quantity of these by-products is generally discarded, leading to environmental problems. This research aims to evaluate the effects of fermentation of Ultrasound (US) treated okara (soy press cakes) on protein oxidation level, techno-functional, texture and sensory properties of the meat analogues. Okara samples were fermented by applying L. plantarum P1 and L. acidophilus 308 strains. The meat analogues were produced by adding 3% and 6% fermented okara to the matrices. Fermented okara and matrices were maturated at temperatures 4 degrees C or 18 degrees C, separately. The effects of fermentation conditions, the amount of okara, and the dough maturation temperature, as well as the interaction effect on protein oxidation level, techno-functional, sensory, and textural properties of meat analogues were analysed. The results indicated that okara is a suitable source of fibre, plant-based proteins, and essential amino acids, and demonstrated the potential of the application of fermentation to improve water-holding capacity and sensory properties of meat analogues, as well as to reduce hardness and protein oxidation levels. The study recommended that the optimum condition for producing meat analogues was the application of 6% okara in the matrices fermented by L. plantarum P1, when the matrices and okara are maturated at 4 degrees C for 2 h. The research finally concluded that the use of fermentation process on US-treated okara makes it a suitable component of meat analogues.

关键词： Carbon Capture and Storage   CCS   FVCOM   leakage   monitoring   marine   climate change   bubbles   multi-phase   CO2  

摘要： Carbon storage is required to keep rising global temperatures below 2 degrees C, meanwhile, storage reservoirs monitoring is required for assurance of early detection of potential leakages. Projects such as QICS and STEMM-CCS have used small in-situ experiments to develop detection techniques, tools, and strategies. Given the expense of experiments it is crucial to develop accurate simulation models that replicate observed behaviours and can be extrapolated to many different scenarios. However, anomalies occur between modelled and experimental data, and a key question has been how can the models be improved? This has been approached through the development of a complex modelling system to include the effects of coastal hydrodynamics on very localised experiments, with a new multi-phase leakage model - PLUME, integrated into a high-resolution hydrodynamic model, and linked to a carbonate system for CO2 analysis. The resolution of the nested domains range from 2.5 km at the boundaries to approximately 0.5 - 1.0 m at the release sites. The efficacy of the PLUME model is demonstrated with application to the STEMM-CCS and QICS experimental sites in 120 and 9-12 m water depths respectively. Results show that the newly developed model can predict observed pCO2 and pH changes within acceptable errors. Local effects are shown to be affected greatly by both the resolution and the water currents, with momentary spikes in pCO2 and reductions in pH caused by tidal oscillation. The spatial impacts of the releases are shown to move with the tide, covering a far greater area over a tidal cycle.