The protein properties of germinated naked barley with infrared and hot air-drying and its noodle-making potential

The naked barley was germinated and then carried out with hot air- or infrared drying to explore the physicochemical and functional properties of protein isolated from barley. Moreover, the relationship between protein and the noodles made from wheat and germinated barley flour was evaluated. It was found that germination affected the protein properties, and the protein properties were correlated with the properties of noodles. The content of β-sheet in protein was first increased and then decreased with germination time increased, and the protein had larger emulsification and foaming properties. Besides, the protein isolated from hot air-dried germinated barley had higher gelatinisation enthalpy and secondary structure content. Furthermore, the wheat and germinated barley mixed noodles had increased elasticity and cohesiveness and reduced viscosity and water absorption. The hardness of noodles showed was positively correlated with water absorption capacity, and the extensibility of cooked noodles was positively correlated with the foaming capacity of proteins.     

山茱萸发酵乳饮料加工技术研究

研究采用酸牛乳为主要原料,添加白砂糖、山茱萸汁、柠檬酸、香精、增稠剂、乳化剂、螯合剂等辅料,经均质、杀菌、冷却、灌装等加工工艺制成一种保健型含乳饮料。试验结果为:酸牛乳37%、白砂糖10%、山茱萸汁10%、稳定剂0.55%、柠檬酸0.1%~0.2%、柠檬酸钠0.02%、六偏磷酸钠0.03%、香精0.08%,其余为水;加工工艺参数,料液混合温度30℃~40℃、均质条件18~20 MPa、杀菌条件120℃/20 s、在2℃~6℃条件下存放。     

Automatic monitoring system for individual dairy cows based on a deep learning framework that provides identification via body parts and estimation of body condition score

Body condition score (BCS) is a common tool for indirectly estimating the mobilization of energy reserves in the fat and muscle of cattle that meets the requirements of animal welfare and precision livestock farming for the effective monitoring of individual animals. However, previous studies on automatic BCS systems have used manual scoring for data collection, and traditional image extraction methods have limited model performance accuracy. In addition, the radio frequency identification device system commonly used in ranching has the disadvantages of misreadings and damage to bovine bodies. Therefore, the aim of this research was to develop and validate an automatic system for identifying individuals and assessing BCS using a deep learning framework. This work developed a linear regression model of BCS using ultrasound backfat thickness to determine BCS for training sets and tested a system based on convolutional neural networks with 3 channels, including depth, gray, and phase congruency, to analyze the back images of 686 cows. After we performed an analysis of image model performance, online verification was used to evaluate the accuracy and precision of the system. The results showed that the selected linear regression model had a high coefficient of determination value (0.976), and the correlation coefficient between manual BCS and ultrasonic BCS was 0.94. Although the overall accuracy of the BCS estimations was high (0.45, 0.77, and 0.98 within 0, 0.25, and 0.5 unit, respectively), the validation for actual BCS ranging from 3.25 to 3.5 was weak (the F1 scores were only 0.6 and 0.57, respectively, within the 0.25-unit range). Overall, individual identification and BCS assessment performed well in the online measurement, with accuracies of 0.937 and 0.409, respectively. A system for individual identification and BCS assessment was developed, and a convolutional neural network using depth, gray, and phase congruency channels to interpret image features exhibited advantages for monitoring thin cows.     

Optical properties of dense zirconium and tantalum diborides for solar thermal absorbers

Ultra-high temperature ceramics (UHTCs) are interesting materials for a large variety of applications under extreme conditions. This paper reports on the production and extensive characterization of highly dense, pure zirconium and tantalum diborides, with particular interest to their potential utilization in the thermal solar energy field. Monolithic bulk samples are produced by Spark Plasma Sintering starting from elemental reactants or using metal diboride powders previously synthesized by Self-propagating High-temperature Synthesis (SHS). Microstructural and optical properties of products obtained by the two processing methods have been comparatively evaluated. We found that pure diborides show a good spectral selectivity, which is an appealing characteristic for solar absorber applications. No, or very small, differences in the optical properties have been evidenced when the two investigated processes adopted for the fabrication of dense TaB₂ and ZrB₂, respectively, are compared.     

Response time for primary frequency control of hydroelectric generating unit

For evaluating the power quality in primary frequency control for hydroelectric generating units, the power response time is an indicator which is of main concern to the power grid. The aim of this paper is to build a suitable model for conducting reliable simulation and to investigate the general rules for controlling the power response time. Two huge hydropower plants with surge tank from China and Sweden are applied in the simulation of a step test of primary frequency control, and the result is validated with data from full scale measurements. From the analytical aspect, this paper deduces a time domain solution for guide vane opening response and a response time formula, of which the main variables are governor parameters. Then the factors which cause the time difference, between the power response time and the analytical response time of opening, are investigated from aspects of both regulation and water way system. It is demonstrated that the formula can help to predict the power response and supply a flexible guidance of parameter tuning, especially for a hydropower plant without surge tank.     

Biodiesel potential of the seed oils from some Brazilian native Euphorbiaceae species

In the present study, the oil content, fatty acid composition and physicochemical properties of seed oils and biodiesel from seven species of Euphorbiaceae were analyzed. The oil content from seven Brazilian native Euphorbiaceae species ranged from 25.4 to 48.5%. Nine primarily unsaturated fatty acids were identified in seed oils. Actinostemon concolor and Stillingia trapezoidea seeds accumulated mainly oleic and linoleic acids, whereas in the seeds of Croton floribundus, Croton nepetifolius, Euphorbia comosa and Microstachys corniculata, linoleic and linolenic acids were the main constituents identified. Palmitic and oleic acids were predominantly detected in the seeds of Sapium glandulosum. In general, the oils showed low acidity, viscosity and free fatty acids. The results suggest that the seed oils from A. concolor, S. glandulosum and S. trapezoidea might be a viable alternative for biodiesel production, while those from C. floribundus, C. nepetifolius, E. comosa and M. corniculata seeds have great potential for application in the paint, varnish and lubricant industries. Due to the high content of saturated fatty acids, the seeds of S. glandulosum could also be used to produce soaps and detergents. For most species analyzed, the biodiesel specifications are in accordance with EN 14214 and ASTM D6751 standards.     

Synthesis and optical properties of novel apatite-type NaCa3Bi(PO4)3F:Dy3+ yellow-emitting fluorophosphate phosphors for white LEDs

In this study, novel yellow-emitting fluorophosphate NaCa₃Bi(PO₄)₃F phosphors doped with different concentrations of Dy³⁺ ions were first obtained via high-temperature solid-state reaction. The crystal structure, phase purity, particle morphology, photoluminescence (PL) properties, thermal stability, and luminescence decay curves of the resulting phosphors were then characterized in detail. Under the excitation of 349 nm, the three dominant peaks of the NaCa₃Bi(PO₄)₃F:Dy³⁺ are centered at 480 nm (⁴F_9/2-⁶H_15/2), 577 nm (⁴F_9/2-⁶H_13/2), and 662 nm (⁴F_9/2-⁶H_11/2). The optimal doping concentration of Dy³⁺ ions in the NaCa₃Bi(PO₄)₃F:xDy³⁺ phosphors is x = 5 mol%. The phosphors show excellent thermal stability with high activation energy (E_a = 0.32 eV). Eventually, the synthesized white light-emitting diode (w-LED) demonstrates the Commission International de L'Eclairage (CIE) chromaticity coordinates of (0.341, 0.334), a good correlated color temperature (CCT) of 5083 K, and a high color rendering index (R_a) of 92. Revealing its potential as yellow-emitting phosphors, the feasibility of the fabricated apatite-type NaCa₃Bi(PO₄)₃F:Dy³⁺ fluorophosphate phosphors was confirmed for w-LEDs.     

Investigation of hot air-assisted radio frequency heating as a simultaneous dry-blanching and pre-drying method for carrot cubes

Hot air-assisted radio frequency (HA-RF) heating was studied as a novel method for simultaneous dry-blanching and pre-drying of carrot cubes, and ultrasound-assisted osmotic dehydration (UOD) was also investigated as an improved conventional pre-drying method for comparison. After conventional hot water blanching, UOD was optimized by orthogonal experiment and after 30.0 min UOD treatment at optimal condition (10% sodium chloride, 40% sucrose and 1,4 solid-liquid ratio), moisture content of carrot cubes decreased to 58.5% (w.b.); and after 9.0–12.0 min HA-RF treatment, moisture content decreased to 60.9–71.9% (w.b.) and enzyme activity (peroxidase-POD) could be reduced to <5% at the same time. UOD was better in lowering water activity and retaining redness of carrot cubes, while HA-RF treated samples had higher vitamin C content and better texture. Besides, HA-RF pre-treatment had lower energy consumption (<0.20 kW∙h/kg) than that of hot water blanching plus UOD treatment (0.67 kW∙h/kg). This study indicated that HA-RF was an effective simultaneous dry-blanching and pre-drying method for carrot cubes.Industrial relevanceThis study proposed and investigated hot air-assisted radio frequency (HA-RF) heating as a new simultaneous dry-blanching and pre-drying method for carrots cubes. This technology may replace the conventional blanching and the following pre-dewatering or 1st stage drying process, since HA-RF pretreatment maintained good quality of carrot cubes and had lower energy consumption, and most importantly, this method can blanch and partially dehydrate samples at the same time without using water. Therefore, it holds great potential as the industrial pre-treatment method for drying of fruits and vegetables.     

Impact of various maceration techniques on the phenolic and volatile composition of Chenin Blanc wines

Chenin Blanc, cultivated in cool climate regions, was chosen to evaluate the impact of different maceration techniques on polyphenolic profiles and volatile compounds. Control with no skin contact (CK), cold maceration (CM), cryogenic maceration (CR), separate fermentation before blending (SFB) and extended skin contact during fermentation (ESF) were the five maceration techniques being studied. SFB and ESF techniques resulted in significantly increased polyphenolic compounds compared to the control (P < 0.05), while CM and CR maceration techniques resulted in almost no effect. Meanwhile, for aromatic components, the maximum change was observed in ESF wine, which had significantly highest levels of terpenes, alcohols, esters and acids. However, compared with control wine, CR wine had higher levels of terpenes and esters and SFB wine had higher levels of terpenes and alcohols. This study provides information about prefermentation techniques and additional options for oenologists to produce Chenin Blanc wines with different characteristics.