Søndergaard Anne K, Stahnke Louise H
BioCentrum-DTU, Technical University of Denmark, Lyngby.
Int J Food Microbiol. 2002 May 5;75(1-2):99-109. doi: 10.1016/s0168-1605(01)00729-2.
A laboratory medium inoculated with 20 different Staphylococcus strains was prepared in accordance with a full factorial experimental design investigating the effect of temperature, pH, NaCl and glucose on growth. The 12 strains most suited to growth in a fermented meat environment were inoculated in sausage minces together with Pediococcus pentosaceus, incubated at 25 degrees C for 1 week and the produced aroma compounds collected. The data were analysed by multiple linear regression and partial least squares regression analysis. The results showed that increasing pH and temperature from 4.6 to 6.0 and 10 to 26 degrees C, respectively, increased growth of all strains with strong synergy between temperature and pH. Increasing salt concentration from 5% to 15% w/v decreased growth of most strains, but the effect of pH and temperature was much stronger than the effect of salt. Strains of S. carnosus were more salt tolerant than strains of S. equorum and S. xylosus, especially at high pH and temperature. Addition of glucose up to 0.5% w/v had no significant influence on growth of any of the strains. With regard to aroma production, species characteristics were detected. S. carnosus and S. xylosus were quite different regarding the overall aroma profiles, whereas the profiles of S. equorum lied somewhere in-between. Contrary to S. carnosus, S. xylosus and S. equorum did not produce 2-methyl-1-butanol. On the other hand, in particular, S. xylosus produced more 3-methyl-1-butanol. Except for one of the strains of S. equorum, S. xylosus and S. equorum formed more diacetyl, 2-butanone and acetoin and also more of the methyl-branched ketones arising from degradation of leucine, isoleucine and valine. S. carnosus produced more methyl-branched aldehydes, acids and corresponding esters from leucine, isoleucine and valine compounds that have been correlated with fermented sausage maturity in former studies. S. equorum produced the least of the methyl-branched aldehydes.
根据一项全因子实验设计，制备了接种20种不同葡萄球菌菌株的实验室培养基，该实验旨在研究温度、pH值、氯化钠和葡萄糖对生长的影响。将最适合在发酵肉环境中生长的12种菌株与戊糖片球菌一起接种到绞碎的香肠中，在25℃下培养1周，并收集产生的香气化合物。通过多元线性回归和偏最小二乘回归分析对数据进行分析。结果表明，分别将pH值从4.6提高到6.0以及将温度从10℃提高到26℃，会增加所有菌株的生长，且温度和pH值之间具有很强的协同作用。将盐浓度从5%（w/v）提高到15%会降低大多数菌株的生长，但pH值和温度的影响比盐的影响要强得多。肉葡萄球菌菌株比马胃葡萄球菌和木糖葡萄球菌菌株更耐盐，尤其是在高pH值和温度条件下。添加高达0.5%（w/v）的葡萄糖对任何菌株的生长均无显著影响。关于香气产生，检测到了菌株特性。肉葡萄球菌和木糖葡萄球菌在整体香气特征方面有很大差异，而马胃葡萄球菌的特征则介于两者之间。与肉葡萄球菌相反，木糖葡萄球菌和马胃葡萄球菌不产生2-甲基-1-丁醇。另一方面，特别是木糖葡萄球菌产生更多的3-甲基-1-丁醇。除一种马胃葡萄球菌菌株外，木糖葡萄球菌和马胃葡萄球菌形成更多的双乙酰、2-丁酮和乙偶姻，以及更多由亮氨酸、异亮氨酸和缬氨酸降解产生的甲基支链酮。肉葡萄球菌从亮氨酸、异亮氨酸和缬氨酸化合物中产生更多的甲基支链醛、酸和相应的酯，这些化合物在以前的研究中与发酵香肠的成熟度相关。马胃葡萄球菌产生的甲基支链醛最少。
