Ye K.,Key Laboratory of Animal Products Processing |
Wang H.,Key Laboratory of Animal Products Processing |
Jiang Y.,Nanjing Normal University |
Xu X.,Key Laboratory of Animal Products Processing |
And 2 more authors.
Food Research International
The competitive growth of Listeria monocytogenes and Lactobacillus on vacuum-packaged chilled pork (VPCP) was studied by the use of Real-time PCR assay and selective culture counting method, where the Jameson-effect model and modified Lotka-Volterra model were chosen for the fitting of growth data. Real-time PCR assay was successfully applied to model the growth of the L.monocytogenes and Lactobacillus respectively on VPCP. The Jameson effect was occurred between L.monocytogenes and Lactobacillus when they co-existed in the same culture, and Lactobacillus clearly induced an early stationary phase of L. monocytogenes. The Jameson-effect model could be used to fit the growth curves of L. monocytogenes and Lactobacillus on VPCP. Thus the modified Lotka-Volterra competition model could be used to evaluate the interaction of two bacterial populations during the growth process, and found that the influence from Lactobacillus on L. monocytogenes was much higher than L. monocytogenes on Lactobacillus through the interaction coefficients. In conclusion, bacterial interactions need to be considered in microbial predictive models, which will provide a more practical assessment in predictive microbiology, and the model for the prediction based on the Real-time PCR assay can be used in future studies, especially for research of interaction models. © 2014 Elsevier Ltd. Source
Yang H.,Key Laboratory of Meat Processing and Quality Control |
Yang H.,Key Laboratory of Animal Products Processing |
Yang H.,Nanjing Agricultural University |
Zhang W.,Key Laboratory of Meat Processing and Quality Control |
And 14 more authors.
Emulsion-type sausages were produced, at 80 °C for either 0, 10, 20 or 30 min, using homogeneous Taihu pork batters. Low-field nuclear magnetic resonance (LF-NMR), with or without deuterium oxide (D2O) substitution, evaluated the proton mobility states related to both water and fat molecules, or fat molecules only, respectively, in the sausage samples, during heat-induced gelation. The decreasing trend in the area proportion of main peak T21, reflected a tighter gel structure in emulsion-type sausages. Raman spectra (400-3600 cm-1) revealed decreased α-helix, but increased β-sheet, β-turns and random coil contents, during the gelling process. Moreover, principal component analysis (PCA) showed significant correlations between secondary protein structures with distribution of water and fat in the gel matrix. Furthermore, this study established the relationship of water and fat protons mobility with changes in secondary protein structures, and described the critical time of gel formation in emulsion-type pork sausages. © 2016 Elsevier Ltd. All rights reserved. Source
Wang P.,Key Laboratory of Meat Processing and Quality Control |
Wang P.,Key Laboratory of Animal Products Processing |
Wang P.,Nanjing Agricultural University |
Han M.,Key Laboratory of Meat Processing and Quality Control |
And 11 more authors.
Journal of Texture Studies
Model heat-induced gels were prepared. Compared with the broiler myofibrillar protein (BMP), interactions between porcine plasma protein (PPP) and spent-hen myofibrillar protein (SHMP) were evaluated using rheology, textural analysis, nuclear magnetic resonance and scanning electron microscopy (SEM). The gel hardness of SHMP was higher than that of BMP. PPP had the highest stickiness and immobilized water fraction of all the gels. The plasma and broiler myofibrillar mixed proteins had a storage modulus similar to that of BMP. After mixing SHMP or BMP with PPP, immobilized water fraction was increased by 5.59% or 50.57%, respectively, and the water-holding capacity (WHC) of the latter significantly increased. Addition of PPP transformed SHMP heat-induced gel to a uniform interconnected network. Introducing PPP can improve the WHC and microstructure of SHMP and BMP gels. © 2014 Wiley Periodicals, Inc. Source