In the field of biomanufacturing,发酵罐It is a core production asset responsible for microbial cultivation and product synthesis; its operational stability determines production efficiency and product quality. AndfoamThis issue is nearly ubiquitous in every aerobic or high-density fermentation process.

From recombinant proteins and antibodies to organic acids and enzyme preparations, foam not only affects process stability but also directly impacts product yield, contamination risk, and downstream purification costs.

However, foam overflow and loss of control during process scale-up or daily operations often disrupt fermentation schedules, increase raw material costs, compromise product purity, and even trigger contamination—making it a critical challenge for many in the biomanufacturing industry.

[ 泡沫是怎样“炼成”的？ ]

发酵罐中的泡沫并非简单的气体包裹物，Gas-phase dispersion, presence of surfactants, and continuous bubble inputIt can form bubbles.

气源存在：微生物代谢产生的 CO₂、N₂ 等气体，或好氧发酵中通入的空气，在液体中形成气泡。

Surfactants:Fermentation broths typically contain proteins, peptides, polysaccharides, fatty acids, and certain metabolic intermediates. These substances adsorb at the gas-liquid interface, reducing surface tension and forming an elastic membrane with mechanical strength that prevents bubble rupture.

Continuous bubble input:Mechanical agitators, circulation pumps, or gas distributors continuously generate new bubbles and extend their residence time in the liquid layer, allowing foam to accumulate.

When bubble rise velocity is lower than the liquid circulation speed in the fermenter, foam rapidly accumulates at the top of the vessel, forming a stable foam layer.

The "Two Faces" of Bubbles

Foam has both beneficial and detrimental effects on the fermentation process; its management requires careful balancing based on actual conditions.

正面作用

提高溶氧效率：In aerobic fermentation (e.g., recombinant protein production using E. coli or Pichia pastoris), moderate foaming increases the gas-liquid interfacial area, enhances the oxygen transfer coefficient (KLa), and reduces mixing energy consumption.

Process Status Indicator:泡沫的消泡速度、粘度和外观变化可作为辅助判断指标。例如，原本容易消除的泡沫突然变得持久，可能提示菌体代谢异常或染菌。

Negative Impact

The issues caused by bubbles are not one-dimensional; they spanMaterials, Sterility, Mass Transfer, and Downstream Processingand other aspects:

Product Loss:沫携带发酵液从排气口、观察窗或轴封处溢出，直接造成培养基流失。根据发酵规模不同，一次中等程度的逃液可使产品收率下降 5%~30%，高价值原料的浪费尤其显著。

Contamination Risk:Foam blocking the exhaust filter compromises vessel positive pressure, potentially introducing environmental contaminants. A single contamination event not only results in batch loss but also increases costs for cleaning validation and production downtime.

Instrument signal distortion:Foam contacting the pH, dissolved oxygen electrode, or level sensor sends erroneous signals, disrupting automated control loops such as feed addition and aeration.

影响下游分离纯化：Residual defoamers or surfactants in foam can interfere with downstream processes such as membrane filtration, centrifugation, and extraction, reducing separation efficiency and increasing purification costs.

How to "tame" the bubble?

Chemical defoaming

化学消泡剂通过降低泡沫液膜局部表面张力使气泡破裂。在生物制造过程中常用的消泡剂包括Polyether(e.g., PPG, PE series),Silicone Emulsions and Modified Polysiloxanes, andvegetable oil(for food-grade or specific antibiotic systems).

使用时需预先进行菌种耐受性测试，确认消泡剂对生长和产物表达无抑制作用；可优先选择水分散型聚醚消泡剂，其残留易清洗，对下游层析影响小。

Mechanical Defoaming

Install on tank topRotating Defoaming Paddle(serrated disc, centrifugal impeller) orStatic Defoamer(multi-hole baffle, demister pad), which destroys foam using shear force or inertial impaction.

Suitable for processes sensitive to any chemical additives, such as recombinant protein production without animal-derived ingredients and certain polysaccharide fermentations; however, effectiveness is limited with high-viscosity fermentation broths (e.g., enzyme production via fungal fermentation).

自动化泡沫控制系统

Fermenter ConfigurationFoam Auto-Detection and Antifoam Dosing SystemWhen the foam sensor detects that foam has reached the electrodes, the system first waits 3 to 5 seconds for a stable signal to confirm the reading and rule out false triggers from splashing droplets or transient fluctuations. Once confirmed, the controller opens the defoamer dosing valve and delivers a single pulse injection lasting 0.1 to 0.5 seconds (the minimum effective dose). After dosing, the system monitors for 20 seconds. If the foam level remains above the electrodes, an additional dose of the same amount is administered. If foam persists after three consecutive doses, the system triggers an alarm prompting manual intervention by the operator.

Every bubble in a fermenter results from the complex interplay of fluid dynamics, colloid chemistry, microbial metabolism, and automated control.

For R&D teams, understanding foaming patterns under specific strain and media combinations often addresses root causes more effectively than simply purchasing imported antifoams. For production facilities, establishing a robust foam emergency response plan typically offers cost-benefit advantages comparable to merely increasing agitation speed. These practical insights represent key technical topics for the upcoming Bio-Manufacturing Exhibition.

The 2026 BIO-TECH Manufacturing Industry Expo will be held grandly in Shanghai from 8/27-28.This exhibition is organized by Yimao Medical. Invited guests will be present on-site, including:2000+Attendee,150+ Speaker,50+Premium exhibitors, featuring "Exhibitions - Products - Conferences - PartnershipsFour core modules focused on "breakthroughs in fundamental research and cross-sector industrialization," establishing a benchmark event for the entire bio-manufacturing value chain.

Whether you are an entrepreneur, investor, technical expert, or procurement decision-maker in the bio-manufacturing sector, this exhibition offers a platform to explore the latest policy trends and industry developments, connect with top-tier capital and high-quality projects, and showcase cutting-edge technologies and innovative products.

EMBO Bio-Manufacturing Industry Exhibition

2026-8-27 to 28, 2026

Shanghai, China

Meeting Size

2000+ Attendees, 150+ Speakers, 50+ Exhibitors

Target Audience

Research Sector: University professors, researchers, and young research talent.
技术层：研发总监、工艺工程师、产
Product Development Manager, etc.
Executive Leadership: Founders, CEOs, CTOs
Procurement Director, etc.
Investment Team: Partners and Associates specializing in life sciences investments.

Meeting Location

Crowne Plaza Shanghai Pujiang, Shanghai

会议亮点

“"Innovative 'Four-in-One' Model"Four core modules: Exhibitions, Products, Conferences, and Partnerships—focused on foundational research breakthroughs and cross-sector industrial implementation.
Comprehensive coverage across six core areas: Comprehensive coverage of six core areas: medical aesthetics, bio-based materials, green chemistry, food, agriculture, and AI empowerment.
Deep integration across the entire industry chain：深度联动顶尖科研专家、行业龙头、创新型中小企业、投资机构及上下游供应链，打造生物制造全产业链标杆盛会。
精准商机与高效转化Covers key links across the entire industry chain, creating an efficient platform that integrates cutting-edge technology exchange, supply-demand matching, and procurement negotiations.