Effects of superfine grinding on quality characteristics of Morchella esculenta powder

ObjectiveIn order to explore the effect of superfine grinding on the quality characteristics of Morchella esculenta powder.MethodsVibrating superfine grinding used to prepare M. esculenta powder and the effects of different superfine grinding times on the physicochemical properties and nutrient dissolution were studied.ResultsWith the increase of superfine grinding time, the specific surface area of M. esculenta powder significantly increased, the median particle size D50 decreased gradually, and the micron level could reach in 5 minutes of superfine grinding; The particle size was more well-distributed and the color of the powder was brighter after superfine grinding; The angle of repose, sliding angle and oil holding capacity reached the equilibrium point at 5 minutes, 10 minutes and 10 minutes respectively, and there was no significant change in increasing superfine grinding time. The water holding capacity gradually decreased after reaching the maximum at 5 minutes. while, the bulk density and tap density showed a decreasing trend; With the extension of superfine grinding time, the content of polysaccharide increased continuously, the soluble dietary fiber content decreased after increasing, and reached the highest level at 15 minutes. No significant change was found in protein content and DPPH free radical clearance rate.ConclusionThe physicochemical properties of M. esculenta powder could be significantly affected by superfine grinding and the ultrafine particle size can be selected based on the practical processing needs and purposes

Effect of Steam Explosion Pretreatment on the Quality and Flavor of Pressed Perilla Seed Oil

The effects of different steam explosion pretreatment durations (30, 45 and 60 s) on the quality and flavor compounds of perilla seed oil were studied. The results showed that steam explosion pretreatment had no significant effect on the composition or content of saturated or unsaturated fatty acids in perilla seed oil, and the acid value and peroxide value of the treatment group were significantly higher than the blank group, but still met the requirements of relevant standards. As steam explosion treatment time rose, the L* value decreased, the b* value increased significantly, and the contents of total phenol and total phytosterol increased significantly. The total phenolic contents at 30, 45 and 60 s were 1.95, 2.29, and 2.77 times as high as that of the blank group, respectively, and the total phytosterol contents increased by 5.36%, 6.48%, and 9.33%, respectively. However, there was no significant difference in the contents of total tocopherol or benzopyrene between the treatment and control groups, and the benzopyrene content in each treatment group was much lower than the national standard limit. A total of 23 volatile flavor compounds were identified by gas chromatography-mass spectrometry (GC-MS), and the types and contents of flavor compounds in perilla seed oil increased significantly after steam explosion. Eleven key flavor compounds were identified by combining odor activity value (OAV) and principal component analysis (PCA), and the major volatile flavor components changed from hydrocarbons and esters to aldehydes and heterocyclic flavor compounds. The overall flavor changed from light fruity and floral aromas to roasted oil-like and nutty aromas. The results of this study provide technical references for the preparation of perilla seed oil

Optimization of Enzymatic Hydrolysis Process of Morchella esculenta and Analysis of Volatile Flavor Compounds in Enzymatic Hydrolysate

To optimize the enzymatic hydrolysis process of Morchella esculenta and expore the volatile flavor compounds in its enzymatic hydrolysate, the enzymatic hydrolysis was optimized by response surface design, and the key flavor compounds were identified by headspace-solid phase microextraction-gas chromatography-mass spectrometry (HS-SPME-GC-MS) combined with the odor activity value (OAV). Results indications were as follows: enzyme addition amount of 5000 U/g, pH6.7, enzymolysis temperature at 44 ℃ for 2 h, the hydrolysis degree was 34.11% under the above mentioned conditions and a total of 23 volatile flavor compounds were identified by GC-MS analysis, among which 17 werein blank group and 21 in enzymatic group. After enzymatic hydrolysis process, the content of flavor compounds increased by 203.71%. Aldehydes were the main volatile flavor compounds, accounting for 78.50% of the whole flavor compounds. Compounds with OAV≥1 were further analyzed, including 7 in the blank group and 9 in the enzymatic group. Isovaleraldehyde, phenylacetaldehyde, hexenal, benzaldehyde, nonanal, linalool, 2-amylfuran, limonene and naphthalene were identified as the key flavor compounds in the enzymatic hydrolysate of Morchella esculenta. Enzymatic hydrolysis can promote the release of flavor compounds, thus providing data basis for the flavor utilization, the deep processing and development of seasoning for Morchella esculenta

Comprehensive Evaluation of Weapon Equipment Systems Operational Effectiveness Based on State Space Concept

Abstract In recent years, there are many researches on combat test of weapon equipment systems. However, in the process of comprehensive effectiveness evaluation, there are some shortcomings in the construction of index system, such as index redundancy, experts subjective weighting, which lead to the lack of objectivity and scientificity. Focusing on the objective state of the evaluated object, this paper puts forward an idea of comprehensive evaluation in the efficiency state space (ESS), and uses intelligent data processing method based on principal component analysis to examine the correlation of the underlying indicators of the evaluation index system (EIS), and attempts to conduct a comprehensive evaluation on this basis. Finally, we give the comparison the corresponding new results with the original evaluation results in the references. The data show that comprehensive evaluation under ESS can reduce efficiency calculation dimension from10 to 3. The final efficiency ranking is slightly different from that in the reference, but is much more rational and convincing.</jats:p

Earth Planets Space, xx, xx–xx, xxxx 3-D Coseismic Displacement Field of the 2005 Kashmir Earthquake Inferred from Satellite Radar Imagery

We use radar amplitude images acquired by the ENVISAT/ASAR sensor to measure the coseismic deformation of the 8 October 2005 Kashmir earthquake. We use the offset images to constrain the fault trace, which is in good agreement with the field investigations and the aftershock distribution. We infer a complete 3-D surface displacement field of the Kashmir earthquake using the offset measurements derived from both descending and ascending pairs of SAR images. The peak-to-peak offset is up to (3.9, 3.6, 4.1) meters in the east, north, and up directions respectively, i.e., 2.9 and 4.1 meters along and across the fault assuming striking 325 o. We model the coseismic displacements using a four-segment dislocation model in a homogeneous elastic half-space. We first estimate the source parameters using a uniform slip model. Then we fix the optimal geometric parameters and solve for the slip distribution using a bounded variable least-squares (BVLS) method. The resultant maximum slip is about 9.0 meters at depth of 4-8 km beneath Muzaffarabad. We find a scalar moment of 2.34 × 10 20 Nm (Mw7.55), of which almost 82 % is released in the uppermost 10 km

Facile Method for Fabricating Microfluidic Chip Integrated with Microwell Arrays for Cell Trapping

With the development of biomedical technology, personalized diagnosis and treatment at the single-cell level are becoming more important in the medical field. As one of the most powerful tools, microfluidic chips have shown significant potential for various applications related to cell separation, cell proliferation, and cell behavior analysis. However, fabricating microfluidic devices requires complicated procedures and high-cost equipment. In this study, an optofluidic maskless lithography method was proposed for rapid fabrication of microfluidic devices integrated with microwells. Through the use of this approach, microwells can be on-line designed and the exposure patterns can be modulated. Single or multi polystyrene microspheres were successfully trapped by using the designed microwells. The capture of MCF-7 cells and cell arrays indicated that the microfluidic devices fabricated in the present study can be applied for cell research