产黄青霉发酵鸭肉制品食用品质、微观结构及物理化学特性变化

Effect of Fermentation with Penicillium chrysogenum on Eating Quality,Microstructure and Physicochemical Properties of Duck Meat

为探讨产黄青霉(Penicillium chrysogenum)发酵鸭肉制品的食用品质、微观结构及物理化学特性变化,将产黄青霉接入高温灭菌后的鸭肉中,(27±1)℃下前发酵7 d、30℃下后发酵14 d得到发酵鸭肉制品。采用质构仪、扫描电子显微镜、透射电子显微镜、拉曼光谱仪、低场核磁共振仪和气相色谱(gas chromatography,GC)-质谱(mass spectrometry,MS)联用仪分别分析产黄青霉发酵鸭肉制品的质地、微观结构、蛋白质构象、水分分布和挥发性物质的变化情况。结果表明,产黄青霉发酵鸭肉的硬度和弹性明显降低,黏性明显增加。扫描电子显微镜和透射电子显微镜观察到经产黄青霉发酵的鸭肉无完整肌原纤维,呈无序排列并黏连的颗粒状。拉曼光谱表明,产黄青霉发酵鸭肉蛋白质二级结构中α-螺旋相对含量减少,β-折叠相对含量增加,β-转角和无规卷曲相对含量变化不明显;色氨酸、酪氨酸残基微环境疏水性显著增强(P<0.05)。低场核磁共振研究发现结合水和不易流动水相对含量显著降低(P<0.05)。GC-MS分析表明未发酵鸭肉制品挥发性物质为29种,而产黄青霉发酵鸭肉制品挥发性物质为48种,其中酮类、酯类和酸类是新产生的挥发性物质。产黄青霉可用于生产特定风味和质地的发酵肉制品,为开发可安全食用的发酵鸭肉制品提供了一种新思路。

In order to investigate the effect of fermentation with Penicillium chrysogenum on the eating quality,microstructure and physicochemical properties of duck meat,duck meat was sterilized by autoclaving and inoculated with Penicillium chrysogenum for fermentation for 7 days at(27±1)℃,and ripening for 14 days at 30℃.A texture analyzer,a scanning electron microscope(SEM),a transmission electron microscope(TEM),Raman spectroscopy,low-field nuclear magnetic resonance(LF-NMR)and gas chromatograph(GC)-mass spectrometry(MS)were used to evaluate changes in the texture,microstructure,protein conformation,water distribution and volatile components of duck meat.The results obtained showed that the hardness and springiness of duck meat fermented with Penicillium chrysogenum decreased,and the gumminess increased.SEM and TEM results indicated that fermented duck meat had no intact myofibrils with disorderly arrangement and adhesion in the form of particles.Raman spectroscopy showed that the relative content ofα-helix in the protein secondary structure of fermented duck meat decreased and the relative content ofβ-sheet increased,while the relative contents ofβ-turn and random coil did not reveal any changes.The micro-environmental hydrophobicity of tryptophan and tyrosine residues was significantly enhanced(P<0.05).LF-NMR showed that the relative contents of bound water and immobilized water were significantly reduced(P<0.05).GC-MS analysis identified 29 volatile compounds in unfermented duck meat,and 48 volatile compounds in fermented duck meat.Ketones,esters and acids were newly produced volatile compounds.Therefore,Penicillium chrysogenum can be used to produce fermented meat products with specific flavor and texture,which will provide a new idea for the development of fermented duck meat products that are safe to consume.