Technical vs. food-approved antifoams: What are the differences?
During any industrial process, foam can be problematic, affecting efficiency, throughput, product quality and even safety.
Introducing antifoams — agents that are pre-added to suppress and control this troublesome byproduct.
A crucial processing aid for controlling foam-intensive water-based applications, popular antifoam additives include technical grade and food approved products. Within the Akasil® antifoam range that we supply, there are a number of emulsion strengths — 10%, 20% and 30%.
Although the names give a big clue, what are the precise differences between these two types of antifoam emulsion? Which is best for my needs?
Technical vs. food-approved antifoams: the chemistry
Technical grade antifoams are made up of polymers with silicone backbones. The silicone compound consists of a hydrophobic silica dispersed in a silicone oil, providing insolubility in water. This enables the product to sit above the foam wall, occupying its openings and destroying them.
Emulsifiers are added which allow the silicone to disperse quickly, widely and easily. These products are excellent at knocking down surface foam and releasing entrained air.
Food-approved antifoams (or food-compliant antifoams) are higher-spec chemistry. Like technical grade antifoams, they are silicone-based, but are specially formulated for food processing environments and are developed to meet certain standards for use as a foodstuff process-aid.
Meeting the highest level of regulatory approval and European H1, Kosher and Halal certification, these food-approved emulsions have siloxane technology that enables them to occupy foam wall openings in a similar way to their tech-grade counterparts, causing the foam wall to thin and collapse. Food-approved antifoams are stable over a wide range of temperatures and are suitable for hot and cold aqueous systems.
As lower-spec chemistry, technical-grade antifoams are usually more cost effective than their food-approved counterparts which, as mentioned, are specially formulated for process waters where food considerations apply.
Products available in the TG (technical grade) range include:
Products available in the FD (food approved or food compliant) range include:
Technical vs. food-approved antifoams: the key uses
The type of antifoam you need depends on the type of environment you’re using it in.
Technical-grade antifoam uses: for effluents, process water & cooling water
For the majority of foam-susceptible applications, a technical grade antifoam is the natural choice for your needs. As well as being more cost effective, they boast excellent foam kill, low surface tension, chemical inertness, thermal stability and complete insolubility in water.
As you can probably appreciate, areas of application for a tech-grade antifoam are many and varied. Depending on the strength of product, some of the most common include:
- TG10 is commonly used for foam control in effluents: municipal wastewater, industrial liquid waste, landfill and solid waste. They are also used for foam control process waters (recycling, sanitising packaging, mining and mineral processing) as well as for cooling water (boiler treatment, metal working fluids and wire drawing).
- TG20 is commonly used for foam control formulations applications — paints, inks, coatings and adhesives as well as wood preservatives and agrochemicals.
- TG30 holds use for foam control in the chemical industry, in particular for latex emulsions and polymers, organic resins and construction cements and mortars.
Food-approved antifoam uses: for food processing, washing, cleaning & fermentation
Alternatively, if you’re in a setting where food processing considerations apply, then a food-approved (or food-compliant) antifoam will most likely be more suited to your needs.
Such applications commonly include vegetable and fruit washing, meat processing, brine solutions, sugar preparations, digest production, in-line cleaning practice, food-grade adhesive formulation and more.
For example, the FD 10 products are primarily used for processing and washing of meat and fish, dairy products, sugar preparations and vegetables and salads. FD 20 is more suited to fermentation — alcohol, beers and vinegars.
These products are not used directly in food production — they are process aids, seldom ingredients. If you’d like some advice about which antifoam is best suited to your requirements, be sure to send a message to our expert team.
Other types of antifoam products
The Akasil® range also features Antifoam SRE, a high-tech, pH-stable product suited to processes where enhanced alkali and acid resistance is required. This type of antifoam is commonly used in cleaning formulations, water-based processes in the chemical industry and where higher temperatures are encountered.
There are some non-silicone (or ‘organic’) antifoam products on the market. An example includes Airfoam NSA, formulated for textile operations. Due to the relative effectiveness of today’s silicone-based technology, the general use of non-silicone antifoams has declined — they usually require higher doses to work effectively, meaning they are more costly. That said, these types of organic antifoam certainly have their place in effluent treatments and process waters where silicone products are prohibited.
Some antifoam products are specially formulated for niche applications. Take Antifoam 3107 for example, formulated for defoaming in non-aqueous oil refinery operations. another silicone-based antifoam that boasts acid and alkali resistance properties. The full range can be explored on our antifoams category page.
The full range can be explored on our antifoams category page.
Airedale Chemical: UK distributors of the leading Akasil® antifoam range
Got more questions about antifoams? Wondering which product would be perfect for your specific needs?
Our team of experts are on hand and would be delighted to help — to discuss your requirements, simply send us a message, email enquiries@airedalechemical.co.uk or drop us a call on 01535 286 853.
We are leading UK suppliers and distributors of Akasil®’s industry-leading antifoam range on behalf of BRB International. Explore the full range of antifoam products today — the product of over 35 years of innovation and development in siloxane-based technology.
