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The effects of different cooking methods (raw, microwave, steaming and frying) on the volatile components of Ctenopharyngodon idella were analyzed by gas chromatography-mass spectrometry, electronic nose technique and sensory evaluation. The results of gas chromatography-mass spectrometry showed that 78 volatiles were detected in 4 cooking methods, mainly olefin, alkanes, aldehydes, esters and other volatile compounds, and the number and content of components in frying methods were higher than those in other processing groups. The electronic nose and principal component analysis showed that, compared with raw fish, the volatiles of fish was closer between steaming and microwave, and fried one had a greater effect on the volatiles. The results of sensory evaluation showed that the fish smell in four treatments all had a certain fishy and grassy taste, but the fried one was mainly manifested in burnt and greasy taste. In addition, the special volatile compounds such as trans, trans-2,4-decenal, 2-furanaldehyde and 2-amyl furan produced during frying give the smell of roast meat, which could cover the off-odor such as fishy and grassy. In summary, the volatiles of Ctenopharyngodon idella were mainly aldehydes and esters, and compared with raw fish, frying had the greatest impact on the volatile components, which could better reduce the fishy off-flavor, the results would provide a theoretical basis for the development of deep processing technology for Ctenopharyngodon idella meat.

To comprehensively analyze the composition and contribution of volatile components in Rosa sterilis, the headspace solid phase microextraction (HS-SPME) and liquid liquid extraction with solvent assisted flavor evaporation (LLE-SAFE) was used, along with gas chromatography-mass spectrometry (GC-MS) to analyze the volatile components. The odor active value (OAV) was used to evaluate the contribution of volatile components to the overall aroma of R. sterilis juice. The results showed that a total of 115 volatile components were identified using both methods, with 59 identified using HS-SPME and 75 identified using LLE-SAFE. These components included 25 esters, 27 alcohols, 11 aldehydes, 14 ketones, 18 acids, 14 terpenes, and 6 other compounds. Analysis of the odor active value (OAV) showed that 30 volatile components, including isoamyl alcohol, 2-hexenal, ethyl hexanoate, ethyl acetate, butyl acetate, hexanal, and hexanoic acid, contributed strongly to the aroma of R. sterilis. This study provides theoretical support for revealing the aroma profile and chemical essence of R. sterilis.

Traditional food packaging has problems such as nondegradable and poor food safety. Edible films play an important role in food packaging, transportation and storage, having become a focus of research due to their low cost, renewable, degradable, safe and non-toxic characteristics. According to the different materials of edible films substrate, edible films are usually categorized into proteins, polysaccharides and composite edible films. Functional properties of edible films prepared from different substrate materials also vary, single substrate edible films are defective in some aspects. Functional ingredients such as proteins, polysaccharides, essential oils, natural products, nanomaterials, emulsifiers, and so on are commonly added to edible films to improve their functional properties, extend the shelf life of foods, improve the preservation of sensory properties of foods, and make them widely used in the field of food preservation. This paper introduced the classification, characteristics, and modification methods of common edible films, discussed the interactions among the substrate ingredients of composite edible films, the influence of functional ingredients on the properties of edible films, and the effects of modified edible films on the quality of food, aiming to provide new research ideas for the wide application and further study of edible films.

Natural fiber is not suitable for modifying yolk gel as a modifier because of its large size and high compactness. In this study, two kinds of modified cellulose were selected to improve the thermal gel properties of yolk. The results showed that the two kinds of cellulose promoted the formation of ordered structure in yolk gel. The ordered gel network not only improved the texture properties and rheological properties, but also improved the water retention of yolk gel significantly. CMC and CNFC at the same concentration, the modification effect of CMC on yolk gel was better than CNFC because of its excellent dispersion. However, high concentration of CNFC (1.20–1.60%) disrupted the cross-linking and ordered structure formation of yolk protein, and the quality of gel was significantly reduced.

Rosa roxburghii Tratt (RRT) has become popular owing to its high vitamin C content. Volatiles are important factors that affect the quality of RRTs and their processed products. In this study, volatile compounds were extracted using headspace-solid phase microextraction (HS-SPME) and solvent-assisted flavor evaporation (SAFE); 143 volatile compounds were identified by gas chromatography-mass spectrometry (GC–MS), and RRT from different origins were well distinguished based on principal component analysis. 45 odor-active components were identified using gas chromatography-olfactometry (GC-O). Through quantitative descriptive analysis (QDA), there were prominent “grassy” and “tea-like” attributes in RRT. Partial least-squares regression (PLSR) revealed that Longli RRT was greatly related to “tea-like” and “woody” attributes. Among the volatiles identified, alcohols and esters were considered the dominant volatile compounds of RRT, 4-methoxy-2,5-dimethyl-3(2H)-furanone was the most prominent compound. This study enriches the flavor chemistry theory of RRT and provides a scientific basis for optimizing the aroma of RRT and its processed products.

Two edible coatings (gelatin coating and ginger essential oil-gelatin coating) were prepared to maintain the flavor quality of fish fillets at two storage temperatures (4 °C and 25 °C). The effects of coating on fish fillets were evaluated by detecting the physical properties, microstructure, microbial properties, volatile flavor and taste flavor of fish. In the same coating method, fish fillets stored at 4 °C showed better effect than that at 25 °C on maintain water content, color and texture, however, fish fillets stored at 25 °C were closer to fresh fish in volatile flavor and taste flavor than that at 4 °C; whatever the storage temperature, coating could slow down the growth of fish microorganisms, maintain water content, color, texture, volatile flavor and taste flavor of fish fillets; GGC exhibited better effect on maintain flavor quality than GC.