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In this study, the hazards and thermal reaction products were monitored in roasted fish marinated with spices. Correlation analysis and dimensionality reduction analysis were carried out using multivariate statistical analysis methods to explore the effect and mechanism of spices on the generation of multiple hazards in roasted fish, aiming to improve the safety of roasted fish through marinating with spices. The results indicated that six spices, including thyme, prickly ash, red pepper, bay leaf, dried ginger, and black pepper, had a certain inhibitory effect on hazards in roasted fish. The highest inhibitory rates of heterocyclic amines (HAAs), acrylamide (ACY), 5-hydroxymethylfurfural (5-HMF), and polycyclic aromatic hydrocarbons (PAHs) were 65.51%, 61.71%, 35.02%, and 35.10%, respectively. Collectively, black pepper and red pepper had better inhibitory effects. Through non-targeted omics analysis of the thermal reaction products in roasted fish, it was found that various hazards in roasted fish were positively correlated with heterocyclic compounds but negatively correlated with organic acids and their derivatives. It was speculated that spices could reduce the formation of hazards by reducing heterocyclic compounds and increasing organic acids and their derivatives in roasted fish.

Phospholipid is widely found in eggs, poultry, legume seeds and aquatic products, which is prone to oxidation degradation during food processing and storage. Moderate oxidation gives food a special flavor, while excessive oxidation will cause food quality deterioration and a decrease in food flavor. The oxidation of phospholipid could be influenced by light, temperature, and oxygen. Phospholipid oxidation is complex and gives rise to a wide range of products. When used singly, existing analytical techniques cannot accurately evaluate the level of phospholipid oxidation, and the regulation techniques for phospholipid oxidation have limitations from safety and economical perspectives. This paper gives an overview of the mechanism, detection and regulation techniques for the oxidative degradation of phospholipids, which will facilitate a systematic understanding of the oxidative degradation of phospholipids during the processing and storage of meat and aquatic products and may also provide a theoretical basis for regulating food flavor and improving food quality.

In order to study the difference in the encapsulation capacity of different microcapsule wall materials for volatile flavor substances, microcapsules were prepared with seven common wall materials by ultrasonic spray-freeze drying technology and their morphology, encapsulation and slow release capacity for 32 volatiles were evaluated by cold field emission scanning electron microscopy (CFE-SEM), electronic nose (EN), and gas chromatography-mass spectrometry (GC-MS). These results showed that the encapsulation capacity of different wall materials exhibited selectivity for different volatiles. In general, β-cyclodextrin had a stronger encapsulation capacity for the volatile compounds, with a higher encapsulation and release efficiency, so it was an ideal wall material. After 30 minutes of heating, the release profile of volatiles encapsulated by β-cyclodextrin in the EN radar plot was similar to that of free volatiles, indicating that the microcapsules prepared in this study had good slow-release performance. These results provide a theoretical basis for the utilization of microencapsulated products for flavor enhancement and flavor stability improvement in the food field.

By the combined use of metabolomics, flavoromics, and rapid electronic sensory detection technology, this study identified and analyzed the differences in flavor quality of six coffees. The results suggested that 2,6-dimethylpyrazine, 2-ethylhexan-1-ol, acetoin, isovaleric acid, and methyl valerate could be employed as aroma markers to distinguish coffees with different degrees of roasting. Additionally, 48 compounds, including guanine, tryptophan-alanine, crotonic acid, and 1-methyladenosine, were found to be the metabolic difference indicators to distinguish coffee powder from different geographical origins and their mixed samples. The major taste compounds of lightly roasted coffee were 1,4-D-xylose, alanine, isoleucine, and phenylalanine. Maltotriose was found to be a major compound in moderately roasted coffee, which also contained a lesser amount of inosine. The combination of electronic nose and electronic tongue detection with principal component analysis (PCA) could be used for rapid classification and variety identification of coffee. These results provide a theoretical basis and technical support for the production of coffee as well as a reference for establishing standards to evaluate the flavor and quality of coffee.

The eel was used as raw material to optimize the process conditions of grilled eel. The optimum process conditions for grilled eel were determined by the central composite design on the basis of single factor tests for steaming process and grilling process. The result showed that the optimum technological parameters for grilling eel were as follows: steaming temperature of 98 °C, steaming time of 6 min, grilling temperature of 200 °C, roasting time of 4 min. Under the condition, the weightlessness rate and water loss rate of grilled eel decreased to 21.22% and 14.86%, respectively, while the tenderness was 1 978.60 g after steaming process. The sensory score, tenderness, lightness and chromatism of grilled eel in the grilling prad were 71.5, 2 591.97 g, 57.42 and 19.19, respectively. The result indicated that the response surface method is reasonable and feasible to optimize the process condition of grilled eel, which could provide a theoretical basis for the actual production of grilled eel. [ABSTRACT FROM AUTHOR]

Videogrammetric measurement (VM) becomes a focus technique at home and abroad because of its no special requirements on the test model and its non-contact way for wind tunnel testing. VM techniques and their applications for wind tunnel testing in highly developed institutes abroad are firstly introduced in detail, and some problems about the VM used in high speed intermittent wind tunnels at home are analyzed. Dynamic calibration for multi-cameras and sequential images matching technique for the mark points based on motion evaluation are developed in CARDC in order to achieve the high precision pose measurement in noise (about 130dB)/vibration environment. The potential application prospects of VM have been demonstrated by several preliminary testing cases in a 2 meter supersonic tunnel tests and a 2.4 meter transonic tunnel, including angles of attack and sideslip measurement of test model, deformation of full size embedded door and a static aero-elastic test model, which shows the precision of VM is high. On the other hand, VM can be used to determine the optical path difference (OPD) by measuring the deviation displacement field induced by the beams from center of camera to the background points crossing the flow field, provides a new way to research and measure aero-optic effects and flow display at the surface of the testing model, which is simple and needs no expensive coherent sources. [ABSTRACT FROM AUTHOR]