Background

Bloated cucumber defect, resulting from the accumulation of the biologically produced carbon dioxide (CO₂) in the fruit, reduces yield and economic gains for the pickling industry worldwide. It was the aim of this review to identify commonalities among effective strategies to reduce bloater defect and determine the theoretical viability of commercial cucumber fermentations without bloater defect and/or purging.

Scope and approach

This article summarizes the known causes of fermented cucumber bloating defect, including sources of CO₂, and the strategies developed to mitigate the production of the carbonic gas such as controlled fermentation, inoculation of selected starter cultures, cover brine acidification and reformulation and the application of air or nitrogen purging.

Key findings and conclusions

It was understood that microbial activity during fermentation, cucumber tissue respiration, as well as the pressure in the fruits and fermentation tanks, ambient temperature and cover brine composition, impact the levels of dissolved CO₂ in the system. Although the biological conversion of oxygen to CO₂ reduces the cucumbers internal gas pressure, the dissipation of the gas from the tissue is reduced by brining. Once the gas accumulates in the cucumber tissue in concentrations high enough to displace it, the irreversible formation of hollow cavities or bloaters occurs. Residual CO₂ is produced by acid-preserved cucumbers, presumably by tissue respiration, which results in the absence of bloating. Thus, microbial activity seems to contribute most of the CO₂ needed for cucumbers to bloat. It is speculated that colonization of the internal cucumber tissue by indigenous microbes, in particular aerobic gram-negative bacteria, results in the localized production of CO₂ causing bloating defect early in the fermentation. It is concluded that effective manipulation of the microbiota, reduction of dissolved oxygen levels and the use of adequately selected starter cultures may enable cucumber fermentations of acceptable quality without purging.

中文翻译：

---

无需氮气或吹扫空气即可进行商业黄瓜发酵的可行性

背景

水果中生物产生的二氧化碳（CO ₂）的积累导致膨胀的黄瓜缺陷，这降低了全球酸洗行业的产量和经济收益。这篇综述的目的是确定减少膨胀剂缺陷的有效策略之间的共性，并确定无膨胀剂缺陷和/或吹扫的商品黄瓜发酵的理论可行性。

范围和方法

本文概述了导致黄瓜黄瓜膨胀的发酵原因的已知原因，包括CO _2的来源，以及为减轻碳酸气体的产生而开发的策略，例如控制发酵，接种选定的发酵剂，覆盖盐水酸化和重新配制以及应用。空气或氮气吹扫。

主要发现和结论

可以理解的是，发酵过程中的微生物活性，黄瓜组织的呼吸作用以及水果和发酵罐中的压力，环境温度和覆盖盐水的组成都会影响系统中溶解的CO ₂含量。尽管氧气向CO ₂的生物转化降低了黄瓜的内部气压，但通过咸化减少了组织中气体的耗散。一旦气体以足够高的浓度积聚在黄瓜组织中以使其移位，就会发生不可逆的中空空腔或膨胀现象。残留的CO ₂由保存酸的黄瓜产生，大概是由组织呼吸作用产生的，从而导致没有腹胀。因此，微生物活动似乎是造成大部分二氧化碳的原因。黄瓜膨胀需要_2个。据推测，土著微生物特别是需氧革兰氏阴性菌对黄瓜内部组织的定殖导致CO ₂的局部产生，从而在发酵初期引起腹胀缺陷。可以得出结论，该微生物群的有效操作，减少溶解氧水平和使用适当选择起始培养物可以使质量合格的黄瓜发酵，而不需要清洁。