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The effects of different plant extracts (lotus leaf, chrysanthemum, and lemon) on the quality, lipid oxidation, fatty acid composition, and volatile compounds in the fat layer of spiced pork trotters were studied. The obtained results showed that the lotus leaf presented the highest antioxidant activities of all different plant extracts. Changes in the pH, color, and sensory analysis showed that plant extracts had a positive effect on the quality of spiced pork trotters (p <.05). During the processing and storage of spiced pork trotters, the content of unsaturated fatty acids and the types of volatile compounds both presented an obvious increase (p <.05). Inversely, the pH value and the thiobarbituric acid reactive substances (TBARS) of pork trotters all showed a significant decreasing trend (p <.05). This study provided a theoretical basis for natural antioxidants to inhibit the oxidation of fatty meat products. Novelty impact statement: The plant extracts can effectively inhibit the lipid oxidation of trotters. The addition of plant extracts increased the variety of volatile flavor substances in trotters. The addition of plant extracts increased the content of unsaturated fatty acids in trotters. [ABSTRACT FROM AUTHOR]

In this paper, a selected starter culture of Staphylococcus xylosus, Pediococcus acidilactici, and Debaryomyces hansenii was used to produce fermented beef jerky. The influence of inoculating compound starter on the basic nutrition composition, physical and chemical properties, and texture characteristics of jerkies were investigated. The study results demonstrated that the addition of compound starter quickly reduced the beef pH (from 6.46 to 4.42) and increased the total free amino acids and free fatty acids contents. The nitrite residues and histamine content in the fermentation group were significantly lower than that in the control group. The gel electrophoresis pattern showed that part of the macromolecular protein in inoculated samples was gradually degraded into small molecule protein, and some bands disappeared. It can be seen that inoculation of starter can improve the quality, safety, and texture characteristics of fermented beef jerky. Practical applications: Microbial fermentation is a unique and long‐standing way of meat processing and preservation. This study found that the inoculation of compound starters can increase the nutritional value and improve texture, flavor, safety of beef jerky. These results suggest that Staphylococcus xylosus, Pediococcus acidilactici, and Debaryomyces hansenii could be considered as mixed bacterial starters in fermented beef jerky to improve product quality and safety, which provides a theoretical basis for the strain screening and processing of fermented beef products. [ABSTRACT FROM AUTHOR]

Taurine is an amino acid, and product rich in taurine is widely used in the field of functional foods and medicines. There are many wild mussel resources which is inexpensive in the Songhua River Basin of Jilin Province. The wild mussel contains abundant taurine, but its processing utilization rate is low. In this paper, taurine was extracted by using a pulsed electric field (PEF) assisted enzymatic from mussel meat, and the single‐factor test and response surface methodology were used to optimize the extraction process by using a central composite design (CCD). When a PEF assisted enzymatic was applied to the mussel meat, the cells ruptured, and substances such as taurine flowed out. A three‐dimensional graphical surface and a two‐dimensional contour map were constructed based on the RSM test results, which could intuitively reflect the influence of various factors and their interaction on the extraction of taurine. We could see that the results were consistent with the initial single‐factor experiment. The optimal extraction conditions were the electric field strength of 25 kV/cm, the number of pulses of 10, and the enzymolysis time of 2.95 hr. The maximum taurine yield was achieved of 13.77 mg/g. Compared with enzymatic method; the taurine yield was significantly increased by 28.21% with the PEF‐assisted enzymatic extraction process. Taurine could be effectively separated and purified by cation exchange and crystallization and recrystallization. Novelty impact statement: PEF‐assisted enzymatic method was used to extract taurine from mussel meat, and the taurine yield was 13.77 mg/g under the best conditions. The single‐factor test and response surface methodology were used to optimize the extraction process by using a central composite design. Taurine could be effectively separated and purified by cation exchange chromatography and crystallization and recrystallization to obtain better purity and yield. [ABSTRACT FROM AUTHOR]

The effects of rosemary and ginger on the storage quality of western‐style sausage were investigated. Both the additives, the rosemary had the higher total phenol content (31.36 mg GAE/g DW) and the better scavenging capacity (88.12%). Rosemary and ginger increased the a* values of sausage significantly (p <.05). They all decreased the pH values, TBARS values, and volatile basic nitrogen values of sausage significantly (p <.05). With the extension of time, the inhibition effect was more significant (p <.05), which ensured the quality of the sausage. Rosemary increased the hardness, springiness, and chewiness of sausage (p <.05). Ginger reduced the hardness and chewiness (p <.05), but it increased the springiness of sausage (p <.05). Rosemary and ginger could inhibit the growth and reproduction of spoilage microorganisms and extend the shelf life of the products. Shelf life is extended by 4 days when ginger was added, while it was prolonged by 5 days when rosemary was added. Above them, the additives had good antioxidant ability and could improve the quality of the western‐style smoked sausage. Compared with ginger, rosemary had the better effect. Practical applications: Rosemary and ginger have attracted a lot of attention because of their great antioxidant and antibacterial properties. This paper studies the effects of rosemary and ginger on the storage quality of the western‐style smoked sausage. It has shown that rosemary and ginger can improve texture characteristics of the products and keep the color of the product to some extent. Furthermore, they have high total phenol content and good ability to scavenge DPPH and ABTS free radicals. So they can inhibit the growth and reproduction of spoilage microorganisms and extend the shelf life of the products. Shelf life is extended by 4 days when ginger was added, while it was prolonged by 5 days when rosemary was added, which can provide references for the theoretical research on the combination of natural preservatives and air‐conditioned packaging. However, the effect of the combination of rosemary and ginger needs further study. Moreover, the two additives all have a unique taste, which can influence the taste of the products. This problem needs to be solved. [ABSTRACT FROM AUTHOR]

The effects of different paprikas on the sensory properties and the physicochemical properties of spiced beef were studied. Headspace solid phase microextraction and gas chromatography‐mass spectrometry were used to identify the flavor substances in the samples. The results showed that the protein and fat content of the samples with paprika were higher compared to the blank group, which were 24.10–25.60 g/100 g and 3.40–3.70 g/100g, respectively. The scores of flavor and color in the blank group were 6.50 and 6.56, respectively, which were lower than the paprikas treatment group. Among the five paprika treatment groups, the color and taste scores of the samples treated with qixing paprika were higher, which were 8.00 and 8.07, respectively. A total of 145 volatile flavor substances were detected, compared with the control group, there were more volatile flavor substances in the paprika additive groups, indicated that paprika additive could enrich the flavor of spiced beef. Practical applications: Paprika not only has a unique flavor, but also has good antioxidant properties. Spiced beef is popular among consumers. However, the surface color of the product is easy to change due to oxidation, which affects the color of the product, resulting in a decline in product sales and economic losses to the enterprise. In addition, the protein and fat of the product will be lost due to oxidation during processing. Therefore, the effects of different paprika on the color, nutritional value, and volatile flavors of spiced beef were studied. The purpose was to slow down the oxidation of products, improve the color of products, retain the nutritional value, and reduce the loss of enterprises by adding different capsicum. In addition, the volatile flavor of products will directly affect the sensory evaluation of consumers, so it is very important to understand the influence of pepper on volatile flavor compounds and consumption preference for volatile components. [ABSTRACT FROM AUTHOR]

The effects of rosemary extract, grape seed extract (GSE) and green tea polyphenol (GTP) on the physicochemical properties and N‐nitrosamines content of western‐style smoked sausage were investigated. Among the additives, GTP had the highest total phenol content (109.82 mg GAE/g DW) and the best scavenging capacity on ABTS (IC50 = 0.16 g/ml). Rosemary extract and GTP reduced the hardness of sausage (p <.05). Rosemary extract, GSE and GTP reduced the gumminess and chewiness of sausage (p <.05), but had little effects on the cohesiveness and springiness (p >.05). Rosemary extract increased the a* and b* values of sausage significantly (p <.05), GSE and GTP had little effects on color (p >.05). The additives all decreased the pH values, TBARs values of sausage (p <.05) and increased the moisture content in sausage (p <.05). The additives can significantly reduce the residual nitrite and N‐nitrosamines content of western‐style smoked sausage. GTP showed the best effect on TBARs (48.29%), residual nitrite (68.87%) and N‐nitrosamines (61.29%). Above all, the additives had good antioxidant ability and could inhibit the formation of N‐nitrosamines. Compared with other additives, GTP had the best effect. Practical applications: Rosemary extract, GSE and GTP have attracted much attention due to their great antibacterial and antioxidant properties. This paper studies the effects of rosemary extract, GSE and GTP on the quality and N‐nitrosamines concent of western‐style smoked sausage. It has shown that rosemary extract and GTP can increase the moisture content of the products and improve their hardness. Rosemary extract and GSE can improve the color of the product to some extent. Because the three additives have good antioxidant properties, they can be used to extend the shelf life of products. Moreover, the three additives can reduce residual nitrite and inhibit N‐nitrosamine formation, which can provide certain theoretical basis for the development of low nitrate products and cancer prevention. However, the inhibition mechanism of the three additives on N‐nitrosamine formation needs further study. In addition, the three additives all have specific flavor, which can affect the flavor of the products. This problem also needs to be improved. [ABSTRACT FROM AUTHOR]

In this paper, fermented solid beef inoculated with two starter cultures ( Lactobacillus curvatus and Pediococcus pentosaceus) in different inoculums concentration, fermentation time, and fermentation temperature was evaluated for change of protein composition (water-soluble proteins, insoluble protein, and salt-soluble proteins) and nonprotein nitrogen during fermentation and the relevance with textural properties was also investigated. The amount of water-soluble and salt-soluble proteins decreased while nonprotein and insoluble proteins increased as fermentation progressed. With the increase of inoculums concentration from 0.5% to 2.5%, the amount of water-soluble and salt-soluble proteins decreased from 23.8 to 19.6 mg/g and 51.2 to 33.5 mg/g, respectively, and the amount of nonprotein and insoluble proteins increased from 17.8 to 24.4 mg/g and 20.3 to 49.5 mg/g, respectively. During 0 to 32 hr of fermentation, the water-soluble and salt-soluble proteins decreased from 24.4 to16.0 mg/g and 54.0 to 22.0 mg/g, respectively, and the amount of nonprotein and insoluble proteins increased from 16.3 to 30.8 mg/g and 19.6 to 70.5 mg/g, respectively. With the fermentation temperature increased from 20°C to 40°C, the water-soluble decreased from 34.6 to 21.8 mg/g; the amount of salt-soluble proteins decreased from 60.0 to 21.2 mg/g; the nonprotein and insoluble proteins increased from 16.2 to 24.3 mg/g and 29.7 to 70.4 mg/g, respectively. From SDS-PAGE analysis of water-soluble and salt-soluble proteins, solid beef protein tended to degrade to smaller protein, peptide, and amino acid with protease and peptidases enzymes, and partially form large polymers. Hardness, elasticity, gumminess, and chewiness were significantly negatively correlated with water-soluble and salt-soluble proteins, and were significantly positively correlated with insoluble proteins. The optimum inoculum population, fermentation time, and fermentation temperature were 2%, 32 hr, and 35°C, respectively. Practical applications Our paper studied the effects of fermentation conditions including inoculums concentration, fermentation temperature, and fermentation time on the change of protein composition of fermented solid beef and nonprotein nitrogen. Meanwhile, explored the relationship between the protein composition and texture properties. Fermentation degrades proteins into smaller protein, peptides, and free amino acids. It is beneficial for absorption and good for health. And now the fermentation meat products become more and more popular. However, the quality of beef products is related to muscle proteins that the changes of protein molecules can be effectively affected the properties of products. Our preliminary observation provides a theoretical basis for further researches on quality evaluation of fermentation meat products, and hope to improve the quality of fermentation meat products. [ABSTRACT FROM AUTHOR]

High-intensity pulsed electric field (PEF) was used to extract protein from mussel. Results show that PEF extraction speed is much faster, and the extraction yield of protein is higher compared with traditional methods. Variation of PEF parameters and the extraction yield of protein were determined by single-factor experiments. The processing conditions were optimized by response surface methodology. The maximum extraction yield of protein of 77.08% was achieved under the following conditions: electric field intensity of 20 kV/cm, pulse number of 8 and enzymolysis time of 2 h. PEF can be widely used to extract protein with high speed and low pollution. Practical Applications Freshwater mussel is widely cultured in China and plays a very important role in aquaculture business. Recently, thanks to the nutritional value, advantages for human diets and edibleness as other shellfish such as shrimp, clam, lobster, scallop, abalone and crab, mussel is in growing value. It is valuable to exploit it. This study of PEF method to extract protein from mussel is important to utilize the mussel meat. PEF, with advantages of non-thermal performance, speediness, efficiency, low power and low pollution, is currently used for non-thermal pasteurization of food and extraction of value components from different natural sources. The results of this study are helpful to the further research of PEF method of protein extraction of mussel and, as such, are of practical significance. [ABSTRACT FROM AUTHOR]