Cheese has a long history and this naturally fermented dairy product contains a range of distinctive flavors. Microorganisms in variety cheeses are an essential component and play important roles ...during both cheese production and ripening. However, cheeses from different countries are still handmade, the processing technology is diverse, the microbial community structure is complex and the cheese flavor fluctuates greatly. Therefore, studying the general processing technology and relationship between microbial structure and flavor formation in cheese is the key to solving the unstable quality and standardized production of cheese flavor on basis of maintaining the flavor of cheese. This paper reviews the research progress on the general processing technology and key control points of natural cheese, the biochemical pathways for production of flavor compounds in cheeses, the diversity and the role of yeasts in cheese. Combined with the development of modern detection technology, the evolution of microbial structure, population evolution and flavor correlation in cheese from different countries was analyzed, which is of great significance for the search for core functional yeast microorganisms and the industrialization prospect of traditional fermented cheese.
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•Flow information is acquired non-intrusively by a multimodality measurement system.•Flow models are established to accurately calculate phase flow rates.•Phase fractions are measured ...by a conductance sensor and an ultrasonic sensor.•Interfacial velocity and oil velocity are extracted from the Doppler shift signal.•The accuracy of the proposed model is validated through dynamic experiments.
Water-based dispersed wavy flow, whereby the water with dispersed oil droplets moves along the bottom of the pipe and the gas concurrently on the top, is a frequently encountered horizontal oil-gas-water three-phase flow pattern in petroleum production and transportation. Accurate flow metering of each individual phase is significant to academic research and industrial flow assurance. Therefore, we present a combined electrical and ultrasonic sensor to simultaneously and non-intrusively acquire online flowing information. This information includes: the water fraction estimated by the normalized voltage from a conductance sensor, the gas fraction calculated by locating the gas-liquid interface through a pulse-wave ultrasonic sensor consisting of three transducers, and the coupled velocity of oil droplets and gas-liquid interface from Doppler shift signal acquired by a continuous wave ultrasonic Doppler sensor. Based on the limited flowing information obtained by multimodality sensors, a novel theoretical model is established based on the analysis of the momentum balance between different phases to solve phase fractions and phase actual velocities for calculating phase flow rates. To make the model closed and solvable, the interfacial velocity and oil velocity are respectively extracted by decoupling the Doppler shift signal through amplitude-aware permutation entropy and noise assisted multivariate empirical mode decomposition methods. Finally, the phase flow rates are calculated by the solutions of the established model. Dynamic experiments are performed to verify the effectiveness and accuracy of the proposed method and theoretical model. This study could provide a potential solution for non-intrusive phase flow metering of industrial three phase flow.
Recent expansion of the scale of human activities poses severe threats to Earth’s life-support systems. Increasingly, protected areas (PAs) are expected to serve dual goals: protect biodiversity and ...secure ecosystem services. We report a nationwide assessment for China, quantifying the provision of threatened species habitat and four key regulating services—water retention, soil retention, sandstorm prevention, and carbon sequestration—in nature reserves (the primary category of PAs in China). We find that China’s nature reserves serve moderately well for mammals and birds, but not for other major taxa, nor for these key regulating ecosystem services. China’s nature reserves encompass 15.1% of the country’s land surface. They capture 17.9% and 16.4% of the entire habitat area for threatened mammals and birds, but only 13.1% for plants, 10.0% for amphibians, and 8.5% for reptiles. Nature reserves encompass only 10.2–12.5% of the source areas for the four key regulating services. They are concentrated in western China, whereas much threatened species’ habitat and regulating service source areas occur in eastern provinces. Our analysis illuminates a strategy for greatly strengthening PAs, through creating the first comprehensive national park system of China. This would encompass both nature reserves, in which human activities are highly restricted, and a new category of PAs for ecosystem services, in which human activities not impacting key services are permitted. This could close the gap in a politically feasible way. We also propose a new category of PAs globally, for sustaining the provision of ecosystems services and achieving sustainable development goals.
•Dual-modal measurement system containing electrical and ultrasonic sensors is used to measure the gas-oil-water three-phase flow non-intrusively.•A joint analysis method based on ensemble empirical ...mode decomposition of Doppler shift signal and continuous wavelet transform of water holdup signal is proposed to characterize gas-oil-water three phase flow.•The correlation between the flow structure and time-varying velocity characteristics is analyzed.•Models are established to accurately calculate phase velocities of oil-gas-water three-phase flow under different flow regimes.
As a highly complex and random process, oil-gas-water three-phase flow is commonly encountered in petroleum production and transportation. Flow velocity of each individual phase is an important parameter for production estimation and flow assurance. To measure the phase velocity of three-phase flow, a one-side ultrasonic transducer working in continuous wave Doppler mode and a conductance sensor were combined to obtain the Doppler shift signal and the holdup signal. Firstly, the water holdup fluctuations were decomposed by the continuous wavelet transform to get the local wavelet energy (LWE) coefficients map on the time-frequency diagram to characterize the local flow structures of each typical flow regime. Since the ultrasound was reflected and scattered by both liquid droplets and gas bubbles, the Doppler shift signal contains fluctuations in different scales. The Doppler shift signal was then processed by the short-time Fourier transform to reveal the correlation between the time-varying velocity characteristics and the flow structure. Thirdly, the ensemble empirical mode decomposition was used to decompose the Doppler shift signal into different intrinsic mode functions (IMFs), and the first three IMFs were selected as the main IMFs. Finally, combined with the LWE coefficient map to jointly analyze the flow dynamic characteristics, the specific IMFs were found well-correlated with the flow information of the specific phases. The models for phase velocities extraction were then established. The extraction results were validated through dynamic experiments. The root mean square error of the liquid superficial velocity, the gas superficial and the overall superficial velocity are 0.06 m/s, 0.06 m/s and 0.07 m/s respectively.
Purple sweet potato anthocyanins are kinds of natural anthocyanin red pigments extracted from the root or stem of purple sweet potato. They are stable and have the functions of anti-oxidation, ...anti-mutation, anti-tumor, liver protection, hypoglycemia, and anti-inflammation, which confer them a good application prospect. Nevertheless, there is not a comprehensive review of purple sweet potato anthocyanins so far. The extraction, structural characterization, stability, functional activity, application in the food, cosmetics, medicine, and other industries of anthocyanins from purple sweet potato, together with their biotransformation in vitro or by gut microorganism are reviewed in this paper, which provides a reference for further development and utilization of anthocyanins.
Fungi present on grape surface considerably impact grape growth and quality. However, information of the fungal community structures and dynamics on the worldwide cash crop, the Cabernet Sauvignon ...grape, from the budding to ripening stages remains limited. Here, we investigated the succession of fungal communities on Cabernet Sauvignon grapes from an organic vineyard in Xinjiang, China at different developmental stages
via
high-throughput sequencing combined with multivariate data analysis. In total, 439 fungal amplicon sequence variants (ASVs) from six phyla were identified. The fungal communities differed over the budding to the berry stages. Moreover,
Aspergillus
,
Malassezia
,
Metschnikowia
, and
Udeniomyces
were predominant during the unripe stage, whereas
Erysiphe
,
Cryptococcus
,
Vishniacozyma
, and
Cladosporium
were dominant in the ripe stages. Notably,
Vishniacozyma
was the most abundant genus, conserved in all development stages. Moreover, network analysis resulted in 171 edges—96 negative and 75 positive. Moreover, fungal genera such as
Vishniacozyma
,
Sporobolomyces
,
Aspergillus
,
Alternaria
,
Erysiphe
,
Toxicodendron
, and
Metschnikowia
were present in the hubs serving as the main connecting nodes. Extensive mutualistic interactions potentially occur among the fungi on the grape surface. In conclusion, the current study expounded the characteristics of the Cabernet Sauvignon grape fungal community during the plant growth process, and the results provided essential insights into the potential impacts of fungal communities on grape growth and health.
Accurate measurement of flow parameters of multiphase flow has great significance for safe, economic, and efficient operation of the industrial production process. To simultaneously measure the water ...holdup and velocity, a combined electrical and ultrasonic Doppler measurement system based on a compact peripheral component interconnect (CPCI) bus is designed. The combined sensor consists of a six-ring conductance sensor, two pairs of capacitance plate sensors, and an ultrasonic Doppler sensor. The measurement system is cored with a field-programmable gate array (FPGA) and consists of a series of functional modules. Through flexible programming and interboard communication, the system can meet different measurement requirements. To meet industrial data transmission standards and increase system extensibility, the demodulated data are transmitted to a host computer through the CPCI bus for further data analysis. Dynamic experiments demonstrated that the multimodal system has stable and preferable performance in water holdup and velocity measurement under all flow patterns. The conductance and capacitance sensor could realize the water holdup measurement with the root-mean-square error (RMSE) of 3.02% and the overall superficial velocity estimation through cross correlation with the RMSE of 0.09 m/s. Besides, the pulse ultrasonic Doppler transducer could measure the overall superficial velocity through the area integration of the velocity profile with the RMSE of 0.08 m/s.
Indoor fires pose significant threats in terms of casualties and economic losses globally. Thus, it is vital to accurately detect indoor fires at an early stage. To improve the accuracy of indoor ...fire detection for the resource-constrained embedded platform, an indoor fire detection method based on multi-sensor fusion and a lightweight convolutional neural network (CNN) is proposed. Firstly, the Savitzky-Golay (SG) filter is used to clean the three types of heterogeneous sensor data, then the cleaned sensor data are transformed by means of the Gramian Angular Field (GAF) method into matrices, which are finally integrated into a three-dimensional matrix. This preprocessing stage will preserve temporal dependency and enlarge the characteristics of time-series data. Therefore, we could reduce the number of blocks, channels and layers in the network, leading to a lightweight CNN for indoor fire detection. Furthermore, we use the Fire Dynamic Simulator (FDS) to simulate data for the training stage, enhancing the robustness of the network. The fire detection performance of the proposed method is verified through an experiment. It was found that the proposed method achieved an impressive accuracy of 99.1%, while the number of CNN parameters and the amount of computation is still small, which is more suitable for the resource-constrained embedded platform of an indoor fire detection system.
Kazak cheese is a traditional dairy product fermented by lactic acid bacteria (LAB) in Xinjiang. To investigate the LAB in Kazak cheese and their contributions to cheese fermentation, four ...representative LAB,
B8,
B6,
B14, and
B10, were isolated from Kazak cheese and subsequently used to ferment cheeses, which were named StC, LhC, WcC, and LrC, respectively. The result showed that most of the physical and chemical indicators had no significant difference, except for moisture and fat.
B14 was beneficial to the production of amino acids, whereas
B8 promoted the formation of organic acids and contributed to formation ideal texture property. Furthermore, the four cheeses all possessed a strong fruity aroma, with brandy, sweet, herbaceous, pungent, and fatty aromas being the most prominent in WcC. This is because
B6 produced a high concentration of hexanal, nonanal, octanal, 3-methylbutanoic acid, ethyl acetate, ethyl butanoate, isoamyl acetate, and ethyl hexanoate in LhC. Research on the fermentation mechanism of LAB in cheese will provide a theoretical basis for the quality control and industrial production of Kazak cheese.
Petit Manseng is widely used for fermenting sweet wine and is popular among younger consumers because of its sweet taste and attractive flavor. To understand the mechanisms underlying spontaneous ...fermentation of Petit Manseng sweet wine in Xinjiang, the dynamic changes in the microbial population and volatile compounds were investigated through high-throughput sequencing (HTS) and headspace solid-phase microextraction (HS-SPME) coupled to gas chromatography-mass spectrometry (GC-MS) technology, respectively. Moreover, the relationship between the microbial population and volatile compounds was deduced
via
multivariate data analysis.
Candida
and
Mortierella
were dominant genera in Petit Manseng wine during spontaneous fermentation. Many fermentative aroma compounds, including ethyl octanoate, isoamyl acetate, ethyl butyrate, ethyl decanoate, isoamyl alcohol, ethyl laurate, isopropyl acetate, hexanoic acid, and octanoic acid, were noted and found to be responsible for the strong fruity and fatty aroma of Petit Manseng sweet wine. Multivariate data analysis indicated that the predominant microorganisms contributed to the formation of these fermentative aroma compounds.
Hannaella
and
Neomicrosphaeropsis
displayed a significantly positive correlation with the 6-methylhept-5-en-2-one produced. The current results provide a reference for producing Petit Manseng sweet wine with desirable characteristics.
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