Fleming H P, McFeeters R F, Humphries E G
Food Fermentation Laboratory, U.S. Department of Agriculture, Agricultural Research Service, and North Carolina Agricultural Research Service, Department of Food Science, North Carolina State University, Raleigh, North Carolina 27695-7624.
Biotechnol Bioeng. 1988 Feb 20;31(3):189-97. doi: 10.1002/bit.260310302.
A fermentor was designed and constructed for study of the physical, microbiological, and chemical changes that occur during the sauerkraut fermentation. The fermentor has some essential features that include restriction in volume of the sauerkraut bed, construction of clear plastic to permit visual determination of liquid-level changes as a result of gas entrapment within the sauerkraut bed, and a gas-lift device for use in nitrogen purging of the fermenting brine. Fermentations exhibited two distinct stages, the first one gaseous and the second non-gaseous. The gaseous stage was characterized by rapid CO(2) and acid production due to growth by hetero-fermentative lactic acid bacteria with resultant gas entrapment within the sauerkraut bed and a rise in liquid level. Also, rapid disappearance of fructose and rapid appearance of mannitol occurred during this stage. The nongaseous stage was characterized by growth of homo-fermentative lactic acid bacteria with little or no CO(2) production and a gradual increase in lactic acid until all fermentable sugars were metabolized. Nitrogen purging appeared to offer several potential advantages, including a means for brine circulation, removal of CO(2) from the brine, and anaerobiosis to ensure retention of ascorbic acid, desirable color, and other oxygen-sensitive traits in sauerkraut.
设计并建造了一个发酵罐，用于研究酸菜发酵过程中发生的物理、微生物和化学变化。该发酵罐具有一些基本特征，包括限制酸菜床的体积、采用透明塑料建造以允许直观确定因酸菜床内气体截留导致的液位变化，以及用于对发酵盐水进行氮气吹扫的气升装置。发酵过程呈现出两个不同阶段，第一个阶段为气态阶段，第二个阶段为非气态阶段。气态阶段的特征是由于异型发酵乳酸菌生长而快速产生二氧化碳和酸，导致酸菜床内气体截留且液位上升。此外，在此阶段果糖迅速消失，甘露醇迅速出现。非气态阶段的特征是同型发酵乳酸菌生长，几乎不产生或不产生二氧化碳，乳酸逐渐增加，直至所有可发酵糖被代谢。氮气吹扫似乎具有几个潜在优势，包括盐水循环的一种方式、从盐水中去除二氧化碳以及确保酸菜中抗坏血酸、理想色泽和其他对氧敏感特性得以保留的厌氧环境。
