Bartowsky E J, Xia D, Gibson R L, Fleet G H, Henschke P A
The Australian Wine Research Institute, Glen Osmond, SA, Australia.
Lett Appl Microbiol. 2003;36(5):307-14. doi: 10.1046/j.1472-765x.2003.01314.x.
To determine the bacterial species associated with an outbreak of spoilage in commercially bottled red wine where the bottles had been stored in an upright vertical compared with horizontal position.
Bottled wines comprising Cabernet Sauvignon, Pinot Noir, Shiraz, Merlot and blended red varieties were examined for visible spoilage. Analysis of visibly affected and non-affected wines revealed a spectrum of aroma and flavour defects, ranging from loss of fruity aroma, staleness, oxidized character to overt volatile acidity. Only acetic acid bacteria, and not yeast or lactic acid bacteria, could be isolated from both spoiled and unspoiled wines and were found to grow only on Wallerstein Nutrient (WL) medium supplemented with 10% red wine or 1-2% ethanol. Analysis of the 16S rRNA region and RAPD-PCR analysis showed the isolates to be a closely related group of Acetobacter pasteurianus, but this group was differentiated from the group comprising beer, vinegar and cider strains.
A. pasteurianus was the species considered responsible for the spoilage but the isolates obtained had atypical properties for this species. In particular, they failed to grow on WL nutrient medium without ethanol or wine supplementation. Storage of the bottles of wine containing A. pasteurianus in an upright vertical position specifically induced growth and spoilage in a proportion of the bottles under conditions that were inhibitory for horizontally stored bottles. We hypothesize that the upright position created a heterogeneous environment that allowed the growth of bacteria in only those bottles sealed with cork closures that had upper limit for the natural permeability to oxygen. Such a heterogeneous environment would not exist in horizontally stored bottles as the larger volume of wine adjacent to the cork would strongly compete with the bacteria for the oxygen as it diffuses through the cork closure.
A low level of bacteria (acetic acid bacteria) in wine can proliferate and cause wine spoilage in bottles stored in an upright vertical as opposed to an horizontal position under conditions that would normally limit bacterial development.
确定与商业瓶装红酒变质爆发相关的细菌种类，这些瓶子分别以直立和水平方式存放。
对包含赤霞珠、黑皮诺、设拉子、梅洛及混合红葡萄品种的瓶装葡萄酒进行可见变质检查。对明显受影响和未受影响的葡萄酒进行分析，发现了一系列香气和风味缺陷，从果香丧失、陈旧感、氧化特征到明显的挥发酸。仅从变质和未变质葡萄酒中分离出醋酸菌，而非酵母或乳酸菌，且发现其仅在添加10%红酒或1 - 2%乙醇的沃勒斯坦营养（WL）培养基上生长。对16S rRNA区域的分析和随机扩增多态性DNA - 聚合酶链反应（RAPD - PCR）分析表明，分离菌株是一组密切相关的巴斯德醋酸杆菌，但该组与包含啤酒、醋和苹果酒菌株的组有所不同。
巴斯德醋酸杆菌被认为是导致变质的菌种，但所获得的分离菌株具有该菌种的非典型特性。特别是，它们在未添加乙醇或葡萄酒的WL营养培养基上无法生长。将含有巴斯德醋酸杆菌的葡萄酒瓶直立存放，在抑制水平存放瓶子的条件下，特定比例的瓶子中会引发细菌生长和变质。我们推测，直立位置创造了一个异质环境，使得只有那些用软木塞密封且氧气自然渗透率有上限的瓶子中的细菌能够生长。水平存放的瓶子中不会存在这样的异质环境，因为靠近软木塞的大量葡萄酒会在氧气通过软木塞扩散时与细菌强烈竞争氧气。
葡萄酒中低水平的细菌（醋酸菌）在通常会限制细菌生长的条件下，与水平存放相比，直立存放的瓶子中会增殖并导致葡萄酒变质。
