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Abstract Chinese cooking is the primary treatment method for table food in China. The process is complex and large‐scale, which is important to the macroeconomy and national nutrition and health. First, this article puts forward the concept of thermal accumulation for Chinese cooking by taking pork tenderloin fried at different oil temperatures, explaining changes in moisture content, hardness, and color with different thermal accumulation conditions, and measuring kinetic parameters. The variations of L* and b* obtained by the experimental results belong to the first‐order reaction kinetic model, while the changes in water content and shear force belong to the zero‐order reaction kinetic model. Simultaneously, the superheat value is used as a thermal accumulation indicator, combined with sensory evaluation to determine that the Z value of the human sensory overheating of pork tenderloin is 99°C, and Os,max (Z = 99°C, the reference temperature is 110°C) is 5.86 min.

Coix seed (CS) has high nutritional value, but the deep processing of CS is relatively limited. Sprouting can significantly improve nutritional value, laying the foundation for efficient consumption or further processing. The optimal conditions for the germination of CS are a soaking temperature of 36 °C for 10 h and a germination temperature of 29 °C for 24 h. Under these conditions, the final germination rate of CS reached 90%. Additionally, the content of γ-aminobutyric acid was 21.205 mg/100 g; soluble protein, free amino acids, γ-aminobutyric acid, and other essential substances increased in CS. Especially after germination, the γ-aminobutyric acid (GABA) content increased by 7.8 times compared with the GABA content of ungerminated CS. Therefore, the nutritional value and flavor of germinated CS are better than those of ungerminated ones, which establishs a solid foundation for its application in developing various products such as compound health drinks, coix yogurt, and others.

Trametes versicolor can produce aromatic flavor in growth and development, widely used in food fermentation. This study used a One-Factor-at-a-Time (OFAT) test and response surface analysis to study the optimum fermentation parameters of Rosa roxburghii tratt and coix seed yogurt by Trametes versicolor. The best fermentation process is as follows: skim milk powder 17 %, sucrose content 4 %, Rosa roxburghii tratt and coix seed liquid 36 %, fermentation temperature 39 °C, inoculum 2 %, strain ratio 2:1:1(LB12: BLH1: Q-1), fermentation time 9.5 h. Under this fermentation process, the sensory score was 82.11, the contents of vitamin C, GABA, and total live bacteria in this yogurt were 13.89, 2.58, and 1.02 times higher than in common yogurt. Correlation analyses showed a significant contribution of the leavening agent to the GABA content of yogurt. This study provides a foundation for producing Rosa roxburghii tratt and coix seed yogurt with high sensory and nutritional value.

A new Rosa roxburghii Tratt (RRT) and coix seed (CS) beverage rich in multi-active ingredients was developed. Edible mushrooms and L. plantarum were selected for fermentation in stages. Some physicochemical properties, γ-aminobutyric acid (GABA), polysaccharides and sensory were studied during the T. versicolor and L. plantarum fermentation. T. versicolor increased the free amino acid through enzymatic protein digestion in the early growth stage and used these amino acids to synthesize its bacteriophage protein. T. versicolor and L. plantarum increased the polysaccharide and GABA of the fermentation broth. Vitamin C was retained as much as possible, with a slight loss occurring mainly in the aerobic fermentation stage of T. versicolor. Its less loss in exchange was for a higher value of T. versicolor polysaccharide, protein enhancement, and bitterness reduction. This study provides a reference for the deep processing of Guizhou's unique agricultural products and edible mushroom fermented beverage.

A producing-fibrinolytic enzyme strain was isolated with high yield. The strain was identified as Bacillus amyloliquefaciens. B. amyloliquefaciens GUTU06 fibrinolytic enzyme was purified by acetone precipitation and reverse micelle. Acetone precipitation condition and reverse micelle condition were examined. Results showed that the total reverse micelle extraction efficiency was 64.49 % ± 1.6 %. The purification fold of the entire process reached 13.38. The optimum pH of purified enzyme is 5, and the optimum temperature is 45 °C. Fe3+ and K+ can enhance the fibrinolytic activity of the enzyme. Compared to commercial fibrinolytic enzymes such as urokinase and lumbrukinase, GUTU06 fibrinolytic enzymes have a lower pH optimal range and higher temperature stability. The molecular weight of the enzyme was approximately 28 kDa. Reverse micelle extraction with cetyl trimethylammonium bromide as a surfactant combined with acetone precipitation is suitable for separating and purifying fibrinolytic enzymes and a promising technique for obtaining active proteins.

On 21 May 2021, the MS 6.4 earthquake struck Yangbi County, Dali City, Yunnan Province. Minor seismic activities were common both before and after the earthquake; the foreshock sequence activity characteristics of this earthquake were studied to gain a better understanding and more perspective. First, between May 18 and 5 July 2021, we collected data of the seismic events from the Yangbi MS 6.4 earthquake sequence, determined the minimum magnitude of completeness of the sequence based on the magnitude-frequency relationship, filtered out the more complete earthquake sequences, and performed double-difference earthquake relocation using the HypoDD method. Then, we improved the nearest-neighbor distance algorithm and used it in conjunction with the Gaussian mixed model fitting method to conduct a comprehensive multiple factor analysis of the Yangbi MS 6.4 earthquake sequence. The main findings of our preliminary analysis are as follows: 1) We distinguished the foreshocks, mainshocks, and aftershocks of the Yangbi earthquake sequence as well as their higher-order aftershocks, using the method described in this paper, and we can obtain clear intergenerational relationships between them. We identified eight “foreshocks” with statistically greater physical significance than the others and found that majority of the shocks occurred shortly after the mainshock were direct aftershocks, with secondary or higher-order aftershocks gradually increasing in the later stage of the sequence. 2) Combining the double-difference earthquake relocation and the event distribution on the fault plane, we found that the b-value of the Yangbi foreshock sequence was clearly on the lower end of the spectrum, with an obvious nonlinear amplification process, and can be divided into three foreshock sub-sequences: sub-sequence I with the lowest b-value and a concentrated spatial distribution, which is an F-value foreshock sequence; subsequence II with an overall shallower source depth and an obvious rebound in b-value, which is an explosive aftershock sequence; subsequence III with a lower b-value and a rapid rupture spread, which is a typical U-F-ρ foreshock. 3) We constructed a topological tree of the Yangbi foreshock sequence in Yunnan Province using the nearest-neighbor distance algorithm, combining the correlation between earthquake sequence type and fault rupture intensity. We analyzed the distribution and topology of the three sub-sequences (combined) of the Yangbi MS 6.4 foreshock sequence and found the following: the topology of subsequence I was more linear than the sequence II, each was the parent event of the subsequent event, and its rupture mode was similar to the fluid intrusion rupture in a specific channel; sequence II had a relatively simple topology, exhibiting a spray topology, and independently formed a main-aftershock mini-sequence, probably triggered by its shallow brittle rupture, which caused the fluid intrusion rupture to spread faster and eventually triggered the Yangbi MS6.4 mainshock.

In this paper, we collected the seismic phase arrival data of 14,033 local natural earthquakes above magnitude 3.0 recorded by 435 seismograph stations in the study area provided by the International Seismological Centre (ISC), covering the period from January 2011 to April 2020. We selected the first arrival P- and S-wave arrival time data and obtained 281,859 P- and 112,926 S-wave absolute arrival times and 528,250 P-differential and 207,968 S-differential arrival times. Then we determined 3-D P and S wave velocity structures from the Japan Trench to the back arc area under the Japan Islands by using double-difference tomography method. The results show strong lateral heterogeneities under the forearc region. The subducting Pacific slab is imaged clearly as a high-velocity (high-V) faster than the surrounding mantle. Low-velocity (low-V) zones are imaged in the mantle wedge with significant along arc variations under the volcanic front. The vertical section shows that the low velocity zone extends to a depth of approximately 70–150 km below the arc. The crust and mantle wedges beneath the front and back arcs of the volcanoes reveal a low-V anomaly, the likely main source of which is the partial melting of plate and mantle wedge material. Referring to the previous results of plate dehydration, mineral composition and thermal state, it is found that fluids play a crucial role in the arc magmatism and plate melting of mantle wedge behind Japan Trench. The fluids brought down by the Pacific subducting plate are released into the mantle wedge by dehydration and subsequently transported upward by the upwelling flow in the mantle wedge. The present results obtained using new and advanced imaging methods enrich the understanding of the velocity structure beneath Japan Islands, which may improve the understanding of the dynamic processes of subduction zones and mantle upwelling.

Predicting the number of microorganisms has excellent application in the food industry. It helps in predicting and managing the storage time and food safety. This study aimed to establish a new, simple, and effective model for predicting the number of microorganisms. The dimensional analysis model (DAM) was established based on dimensionless analysis and the Pi theorem. It was then applied to predict the number of Pseudomonas in Niuganba (NGB), a traditional Chinese fermented dry-cured beef, which was prepared and stored at 278 K, 283 K, and 288 K. Finally, the internal and external validation of the DAM was performed using six parameters including R2, R2adj, root mean square error (RMSE), standard error of prediction (%SEP), Af, and Bf. High R2 and R2adj and low RMSE and %SEP values indicated that the DAM had high accuracy in predicting the number of microorganisms and the storage time of NGB samples. Both Af and Bf values were close to 1. The correlation between the observed and predicted numbers of Pseudomonas was high. The study showed that the DAM was a simple, unified and effective model to predict the number of microorganisms and storage time.

Suantang beef is a traditional delicious Chinese food cooked in Suantang (ST, a sour soup fermented by microorganisms). However, the impact of ST on beef quality is unclear, and the process of ST beef lacks unified technical standards. In the presented study, we found that the additional amount of salt, cooking time, meat thickness, and beef–ST ratio significantly affect the quality of ST beef. After optimization, it was found that when salt addition was 1%, cooking time was 3 min, meat thickness was 2 cm, and beef–ST ratio was 40%, the color determined by colorimeter, texture determined by texture analyzer, and sensory scores of beef cooked by ST were improved compared with boiled beef. ST decreased the pH value and cathepsin L activity of beef, increased the content of organic acid, and changed the protein composition of beef. ST made the beef have higher hardness, and have better chewiness and cohesion. At the same time, ST reduced the disagreeable odors of beef and improved beef flavor. In addition, 88 volatile compounds were detected in ST beef by HS-SPME/GC-MS. According to odor, threshold, and odor activity value (OAV), 24 critical aroma-active compounds were confirmed in ST beef. This study provides a basis for the potential industrialized production of ST beef.

Hongsuantang (HST) is a traditional Chinese and famous sour soup. However, the quality of naturally fermented HST is not controllable. We investigated the effects of different lactic acid bacteria starters on HST acid production, color, antioxidant capacity, total phenols, total carotenoids, organic acids, volatile substances, and sensory properties to determine the most suitable strain for HST production. The results showed that among the seven lactic acid bacteria strains used to inoculate fermented HST, Lactiplantibacillus plantarum SQ-4 exhibited the most excellent fermentation characteristics. SQ-4 rapidly reduced the HST’s pH by 0.77. It significantly increased the HST’s color, organic acids, total phenols, carotenoids, lycopene, and free radical scavenging ability. Lactiplantibacillus plantarum SQ-4 was an excellent starter for preparing HST with good acid production capacity, moderate sourness and spiciness, and good sensory and other characteristics. Each starter produces its distinct flavor components. α-Pinene, myrcene, α-copaene, and guaiol were vital aroma compounds in HST fermentation by the starter. This study laid a foundation for selecting HST starters and potential industrial production.

Lactobacilli have been widely concerned for decades. Bacteria of the genus Lactobacillus have been commonly employed in fermented food to improve the appearance, smell, and taste of food or prolong its shelf-life. They comprise 261 species (by March 2020) that are highly diverse at the phenotypic, ecological, and genotypic levels. Some Lactobacilli strains have been documented to be essential probiotics, which are defined as a group of living microorganisms that are beneficial to the health of the host when ingested in sufficiency. However, the characterization, high-density fermentation, and the production of a directed vat set (DVS) starter of Lactobacilli strains used in the food industry have not been systematically reported. This paper mainly focuses on reviewing Lactobacilli as functional starter cultures in the food industry, including different molecular techniques for identification at the species and strain levels, methods for evaluating Lactobacilli properties, enhancing their performance and improving the cell density of Lactobacilli, and the production techniques of DVS starter of Lactobacilli strains. Moreover, this review further discussed the existing problems and future development prospects of Lactobacilli in the food industry. The viability and stability of Lactobacilli in the food industry and gastrointestinal environment are critical challenges at the industrial scale. The new production equipment and technology of DVS starter of Lactobacilli strains will have the potential for large-scale application, for example, developing low-temperature spray drying, freezing granulation drying, and spray freeze-drying.

Fruit yogurt with a variety of nutrients and fruit flavors is becoming increasingly popular among consumers. This study was conducted to achieve the optimum fermentation process parameters in preparing potato blueberry yogurt with high nutritional value and good flavor and taste by using one factor at a time experiment and response surface methodology. The optimum fermentation process was as follows: 33% potato saccharification solution, 22% blueberry juice, 38 °C fermentation temperature, 3.7% sucrose, 14% skimmed milk powder, 4% concentration of inoculum probiotics including Bifidobacterium animalis subsp. lactis BZ11, Lactobacillus plantarum LB12, and Streptococcus thermophilus Q-1 with their inoculum ratio of 1:1:2 and 12.5 h fermentation time. Potato saccharification solution, blueberry juice, fermentation temperature, and sucrose significantly affected the sensory value and quality of yogurt. Under this fermentation process, the sensory score of yogurt was 89.78. The prepared potato blueberry yogurt was rich in anthocyanins (9.41 mg/100 g), had a potential probiotic viable count of 9.31 log CFU/mL and pleasing color, and overcame the bitterness of potatoes. Electronic tongue analysis also shows that the potato blueberry yogurt had good sensory characteristics, such as high saltiness, umami, and aftertaste-A; low sourness, bitterness, and astringency; and moderate aftertaste-B and richness. This study laid the foundation for producing potato blueberry yogurt with good sensory value and high anthocyanin content.

Natto is a high-value fermented soybean produced by B. subtilis. However, B. subtilis produces a pungent amine odor. This study compared the volatile organic compounds (VOCs), free amino acids (FAAs) and biogenic amines (BAs), nattokinase (NK) of natto made by two-strain fermentation with Bifidobacterium animalis BZ25 and Bacillus subtilis GUTU09 (NMBB) and that of natto made by single-strain fermentation with Bacillus subtilis GUTU09 (NMB). Compared with NMB, volatile amine substances disappeared, ketones and aldehydes of NMBB were reduced, and alcohols increased. Besides that, the taste activity value of other bitter amino acids was lowered, and BA content was decreased from 255.88 mg/kg to 238.35 mg/kg but increased NK activity from 143.89 FU/g to 151.05 FU/g. Correlation analysis showed that the addition of BZ25 reduced the correlation between GUTU09 and BAs from 0.878 to 0.808, and pH was changed from a positive correlation to a negative one. All these results showed that the quality of natto was improved by two-strain co-fermentation, which laid a foundation for its potential industrial application.

Benzo[a]pyrene (BaP), a carcinogen, leads to the severe liver injury. Isoorientin (ISO), a natural flavonoid, is known for its bioactivities, including anti-oxidation, anti-inflammation, and so on. However, there is no report on the effects of ISO on liver injury induced by BaP. The present study demonstrated that ISO treatment could relieve BaP-caused autophagic and pyroptotic injury in HL-7702 human hepatocyte and male BALB/c mice by down-regulating the numbers of autophagosomes, the mRNA expression of LC3 II and Beclin-1, and the levels of pyroptotic characteristic indices. Histopathology stained also confirmed that ISO could suppress the BaP-induced liver injury. Meanwhile, ISO was able to improve the liver function, and remarkably (p

In this study, a sn-1, 3 extracellular lipases from Aspergillus niger GZUF36 (PEXANL1) was expressed in Pichia pastoris, characterized, and the predicted structural model was analyzed. The optimized culture conditions of P. pastoris showed that the highest lipase activity of 66.5 ± 1.4 U/mL (P < 0.05) could be attained with 1% methanol and 96 h induction time. The purified PEXANL1 exhibited the highest activity at pH 4.0 and 40°C temperature, and its original activity remained unaltered in the majority of the organic solvents (20% v/v concentration). Triton X-100, Tween 20, Tween 80, and SDS at a concentration of 0.01% (w/v) enhanced, and all the metal ions tested inhibited activity of purified PEXANL. The results of ultrasound-assisted PEXANL1 catalyzed synthesis of 1,3-diaglycerides showed that the content of 1,3-diglycerides was rapidly increased to 36.90% with 25 min of ultrasound duration (P < 0.05) and later decreased to 19.93% with 35 min of ultrasound duration. The modeled structure of PEXANL1 by comparative modeling showed α/β hydrolase fold. Structural superposition and molecular docking results validated that Ser162, His274, and Asp217 residues of PEXANL1 were involved in the catalysis. Small-angle X-ray scattering analysis indicated the monomer properties of PEXANL1 in solution. The ab initio model of PEXANL1 overlapped with its modeling structure. This work presents a reliable structural model of A. niger lipase based on homology modeling and small-angle X-ray scattering. Besides, the data from this study will benefit the rational design of suitable crystalline lipase variants in the future.

Natto is a popular food because it contains a variety of active compounds, including nattokinase. Previously, we discovered that fermenting natto with the combination of Bacillus subtilis GUTU09 and Bifidobacterium animalis subsp. lactis BZ25 resulted in a dramatically better sensory and functional quality of natto. The current study further explored the effects of different fermentation parameters on the quality of natto fermented with Bacillus subtilis GUTU09 and Bifidobacterium BZ25, using Plackett–Burman design and response surface methodology. Fermentation temperature, time, and inoculation amount significantly affected the sensory and functional qualities of natto fermented with mixed bacteria. The optimal conditions were obtained as follows: soybean 50 g/250 mL, triangle container, 1% sucrose, Bacillus subtilis GUTU09 to Bifidobacterium BZ25 ratio of 1:1, inoculation 7%, fermentation temperature 35.5 °C, and fermentation time 24 h. Under these conditions, nattokinase activity, free amino nitrogen content, and sensory score were increased compared to those before optimization. They were 144.83 ± 2.66 FU/g, 7.02 ± 0.69 mg/Kg and 82.43 ± 5.40, respectively. The plate thrombolytic area and nattokinase activity both increased significantly as fermentation time was increased, indicating that the natto exhibited strong thrombolytic action. Hence, mixed-bacteria fermentation improves the taste, flavor, nattokinase activity, and thrombolysis of natto. This research set the groundwork for the ultimate manufacturing of natto with high nattokinase activity and free amino nitrogen content, as well as good sensory and thrombolytic properties.

There has been research on CaMnO3 with natural abundance, low toxicity, and low cost as promising candidates for n-type thermoelectric (TE) materials. In this paper, Ca1−2xPrxYbxMnO3 with different Pr and Yb contents (x = 0, 0.01, 0.02, 0.03, 0.04 and 0.05) were synthesized by means of coprecipitation. With X-ray diffraction (XRD), scanning electron microscopy (SEM), and high-resolution transmission electron microscopy (HRTEM), researchers characterized the phase structure and morphology of all the samples. The oxidation states of manganese were determined by X-ray photoemission spectroscopy (XPS). The role of Ca-site dual doping in the TE properties was also investigated. Increasing the Pr and Yb contents leads to decreases in the electrical resistivity and Seebeck coefficient, leading to a power factor of 3.48 × 10−4 W·m−1·K−2 for x = 0.04 at 773 K, which is its maximum. Furthermore, the thermal conductivity (κ) decreases with increasing x, and κ = 1.26 W·m−1·K−1 is obtained for x = 0.04 at 973 K. Ca0.92Pr0.04Yb0.04MnO3 exhibit a ZT (thermoelectric figure of merit) value of 0.24 at 973 K, approximately 3 times more than that of the pristine CaMnO3. Thus, the reported method is a new strategy to enhance the TE performance of CaMnO3.

In-situ liquid-phase hydrogenation of m-chloronitrobenzene (m-CNB) based on aqueous-phase reforming (APR) of ethanol and catalytic hydrogenation was carried out over Fe-modified Pt/carbon nanotubes (CNTs) catalysts. The effects of Pt loading over CNTs and Fe modification on the catalytic performance of Pt/CNTs catalysts were studied. In-tube loading of Pt particles, compared with out-tube loading, considerably improved the catalytic activity. With in-tube loading, Fe-modified Pt/CNTs catalysts further improved the m-CNB in-situ hydrogenation performance. After Fe modification, Pt–Fe/CNTs catalysts formed, inside CNTs, a Pt–Fe alloy and iron oxides, which both improved catalytic hydrogenation performance and significantly enhanced ethanol APR hydrogen producing performance, thereby increasing the m-CNB in-situ hydrogenation reactivity.

A series of ZnMgNiAl layered double hydroxides (LDHs) containing 20 wt.% Ni and different Zn/Mg molar ratios were prepared by a coprecipitation method, and then were introduced with H2PO4− via a microwave-hydrothermal method. With the resulting mixtures as the precursors, Zn/Mg-modified ZnMgNi–P/Al2O3 catalysts were prepared. The Zn/Mg molar ratio affected the formation of Ni2P and Ni12P5 in nickel phosphides. The ZnMgNi–P/Al2O3 catalyst with a Zn/Mg molar ratio of 3:1 exhibits the best dibenzothiophene hydrodesulfurization (HDS) activity. Compared with the Ni–P/Al2O3 catalyst prepared from the impregnation method, the ZnMgNi–P/Al2O3 catalyst shows a higher HDS activity (81.6% vs. 54.3%) and promotes the direct desulfurization of dibenzothiophene.

Drynariae Rhizoma is a kidney-tonifying herb that has a long history in clinical practice for the treatment of bone fractures and joint diseases in China. Flavonoids are considered to be its major active ingredients and are reported to ease bone loss in ovariectomized rats. However, the beneficial effects of the total flavonoids of Drynariae Rhizoma on osteoporosis caused by microgravity or mechanical inactivity remain unknown. This study assessed the effects of total Drynariae Rhizoma flavonoids (DRTF, Qihuang, Beijing, China, national medicine permit No. Z20030007, number of production: 04080081, content of DRTF ≥80%) against bone loss induced by simulated microgravity. A hindlimb unloading tail-suspended rat model was established to determine the effect of DRTF on bone mineral density (BMD), biomechanical strength and trabecular bone microarchitecture. Twenty-eight male Sprague–Dawley rats were divided into four groups: the baseline, control, hindlimb unloading with vehicle (HLU), and hindlimb unloading treated with DRTF (HLU–DRTF, 75 mg/kg/day) groups. Oral DRTF was administered for 4 weeks. The underlying mechanisms of the DRTF actions on disuse-induced osteoporosis are discussed. The results showed that DRTF treatment significantly increased the BMD and mechanical strength of tail-suspended rats. Enhanced bone turnover markers with HLU treatment were attenuated by DRTF administration. Deterioration of trabecular bone induced by HLU was prevented through elevated bone volume/tissue volume (BV/TV), trabecular number (Tb. N), trabecular thickness (Tb. Th) and decreased trabecular separation (Tb. Sp). The present study provides the first evidence that DRTF prevents bone loss induced by HLU treatment, indicating its potential application in the treatment of disuse-induced osteoporosis.

Carbon nanotubes (CNTs)-supported Pt nanoparticles were prepared with selective deposition of Pt nanoparticles inside and outside CNTs (Pt–in/CNTs and Pt–out/CNTs). The effects of Pt loading and reaction solvents on phenol hydrogenation were investigated. The Pt nanoparticles in Pt–in/CNTs versus Pt–out/CNTs are smaller and better dispersed. The catalytic activity and reuse stability toward phenol hydrogenation both improved markedly. The dichloromethane–water mixture as the reaction solvent, compared with either pure medium, decreased the catalytic activity toward phenol hydrogenation and selectivity of cyclohexanone over Pt–in/CNTs, but significantly improved the catalytic activity toward phenol hydrogenation and selectivity of cyclohexanone over Pt–out/CNTs.