Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Industrias, Buenos Aires, Argentina; CONICET - Universidad de Buenos Aires, Instituto de Tecnología de Alimentos y Procesos Químicos (ITAPROQ), Buenos Aires, Argentina.
Universidad de Buenos Aires, Facultad de Ciencias Exactas y Naturales, Departamento de Industrias, Buenos Aires, Argentina.
Int J Biol Macromol. 2020 Dec 1;164:1657-1664. doi: 10.1016/j.ijbiomac.2020.07.277. Epub 2020 Aug 7.
This study evaluated the effect of some natural additives and the structure imparted by them on microbial growth and rheological characteristics in acidic model foods with reduced glycidic content. Systems were formulated using gellan gum, as gelling agent; xylitol, as a depressor; and natamycin, as antimicrobial. Additive-free control systems were prepared. The pH was adjusted to 3.50 or 5.50 as required. Systems were inoculated with Zygosaccharomyces bailii. The effect of additives alone and combined on Z. bailii growth was studied. In some cases, the possible use of additives as yeast nutrients was evaluated. Furthermore, systems rheological characterization was performed. Additives and the structure given by gellan gum significantly affected yeast growth. Gellan gum initially slowed Z. bailii development, but as storage progressed, it acted as yeast carbon source, promoting its growth. A similar trend was observed when xylitol effect was studied. Natamycin inhibited yeast growth in all systems assayed. Additives modified the rheological characteristics of the gels and this effect depended on gellan gum concentration and pH. Obtained results emphasize the importance of considering the different effects that additives and their combinations can exert on the growth of deteriorating microorganisms and on the physical characteristics of gels.
本研究评估了一些天然添加剂及其赋予的结构对低糖酸性模型食品中微生物生长和流变性的影响。使用凝胶多糖作为胶凝剂、木糖醇作为甜味抑制剂和纳他霉素作为抗菌剂来配制系统。制备无添加剂对照系统。根据需要将 pH 值调节至 3.50 或 5.50。用酿酒酵母接种系统。研究了添加剂单独和组合对酿酒酵母生长的影响。在某些情况下，评估了添加剂作为酵母营养物的可能用途。此外，还对系统的流变特性进行了表征。添加剂和凝胶多糖赋予的结构显著影响了酵母的生长。凝胶多糖最初减缓了酿酒酵母的生长，但随着储存的进行，它作为酵母的碳源，促进了其生长。当研究木糖醇的影响时，观察到了类似的趋势。纳他霉素抑制了所有测试系统中酵母的生长。添加剂改变了凝胶的流变性特征，这种效应取决于凝胶多糖的浓度和 pH 值。所得结果强调了考虑添加剂及其组合对变质微生物生长和凝胶物理特性的不同影响的重要性。
