Stainless steel or plastic soda maker: what difference does it really make

If you're thinking of buying a soda maker for your home, the first thing you see when you search is a huge offering: from machines costing 25 euros to options exceeding 150. The price difference is so great that it's normal to wonder if it's really worth paying more, or if they all do the same thing.

The short answer is that not all of them do the same thing. And the main difference is not in the functions—they all carbonate water—but in the material, durability, and the real cost you pay over time.

In this article, we compare the three types of soda makers you can find on the Spanish market: basic plastic ones for less than 50 euros, mid-range ones between 90 and 140 euros, and the Congas Burbujito, made of 304 stainless steel. We'll tell you the real technical differences, with data from the manufacturer's manual, so you can decide without surprises.

The three types of soda makers on the market

Basic plastic soda maker (less than 50 EUR)

These are the most economical option and also the most abundant on platforms like Amazon. They work: you connect a standard cylinder, fill the bottle, and press a button. The plastic is usually ABS or similar, without published certifications.

The strong point is the initial price. The weak point is durability: plastic ages, can yellow, absorbs odors over time, and mechanical parts—especially the thread and the bottle's fastening mechanism—tend to develop looseness within 12-24 months of daily use.

The carbonation needle—the part that injects CO2 directly into the water—is usually made of plastic. It is functional at first, but with frequent use, it can wear out and affect carbonation accuracy.

Mid-range plastic soda maker (90-140 EUR)

These machines have more refined designs and better overall finishes. The plastic is of higher quality, the mechanisms are more precise, and the user experience is noticeably better than the basic range.

The common problem with this range is the proprietary cylinder system: many mid-range models use an exclusive bayonet or quick-connect mechanism that is only compatible with cylinders from the same brand. This means you cannot use cylinders from other suppliers, which limits your freedom of choice and usually increases the refill cost.

Congas Burbujito: 304 Stainless Steel Soda maker

The Burbujito is made of 304 stainless steel—the same grade used in professional kitchens and in utensils that require direct and continuous contact with food. It does not rust, does not absorb odors or flavors, does not degrade with daily use, and is easy to clean.

Unlike most soda makers on the market, the CO2 injection needle is also made of stainless steel. It is the part that comes into contact with water with each use, and making it out of steel guarantees consistent precision, greater hygiene, and a much longer lifespan than plastic alternatives.

It uses standard threaded cylinders—the most widespread system in the world—which means full compatibility with cylinders from any brand or distributor, including Congas' Soda Club.

Certifications: the difference you don't see but that matters

This is probably the most overlooked criterion when buying a soda maker and one of the most relevant, especially if you are going to use it daily to prepare water that the whole family will drink.

The Burbujito has three certifications that few soda makers on the market can boast:

•       LFGB (German Food and Feed Code): the most demanding regulation in Europe for materials that come into contact with food. It guarantees that no component releases harmful substances into the water.

•       FDA (Food and Drug Administration, United States): the equivalent North American standard for food-grade materials.

•       ISO 9001: international manufacturing process certification. It guarantees that the machine is produced under controlled and audited quality standards.

Basic unbranded or little-known branded soda makers generally do not report any certification. Mid-range ones usually comply with European CE regulations, which is the legal minimum for sale in Europe, but is not equivalent to the aforementioned certifications.

The real cost: what you pay over time

The initial price of a soda maker is only part of its true cost. The main expense, in the medium and long term, is CO2 cylinders.

With an average family consumption of about 60 liters of sparkling water per month—equivalent to a standard 425g cylinder—the annual cost of refills can vary greatly depending on the type of machine you have:

•       Mid-range soda maker with proprietary system: if you can only use cylinders from one brand, the refill price is usually between 17 and 22 EUR. Between 204 and 264 EUR/year.

•       Burbujito with Soda Club: from 13.50 EUR per cylinder, with empty cylinder collection and home delivery included. Around 162 EUR/year.

Furthermore, when calculating the real cost, you have to consider the useful life. A basic plastic machine that needs replacing after two years effectively doubles what you paid, since you are buying the same product twice. A steel one that lasts 8-10 years distributes it very differently.

Full comparison: features table

 

Feature	Burbujito (Congas)	Basic plastic soda maker (<50 EUR)	Mid-range plastic soda maker (90-140 EUR)
Body Material	304 Stainless Steel	ABS plastic or similar	Improved ABS plastic
Carbonation needle	Stainless steel	Plastic	Plastic or basic metal
Certifications	LFGB + FDA + ISO 9001	Uncertified or no data	CE (minimum European standard)
Cylinder system	Universal standard thread	Standard thread (generic)	Standard thread or proprietary system
Supplier freedom	Total: any compatible brand	Total, although variable quality	Limited or none if proprietary
CO2 refill price (60L)	From 13.50 EUR (Soda Club)	Variable (10-20 EUR)	Variable or own brand only (17-22 EUR)
Bottles included	2x 1L bottles (value ~40 EUR)	1 generic bottle	1 branded bottle
Pressure release system	Integrated and silent	Basic or absent	Standard
Carbonation control	Manual by pulses	Basic manual	Manual by pulses
Maximum operating pressure	0.65 MPa (published)	No official data	Not usually published
Estimated lifespan	High (metal, no degradation)	Limited (1-3 years typical)	Medium (3-5 years)
Design	Premium minimalist	Basic functional	Modern or retro depending on range
Subscription / automatic refill	Yes (Soda Club, with collection)	No	No
Initial price	170 EUR (bottles included)	25-50 EUR	90-140 EUR

 

Data based on Congas manufacturer's technical specifications and general market characteristics as of March 2026. Third-party soda maker characteristics are representative of their price category, not of any specific model.

Scorecard by criteria

 

Criterion	Burbujito	Basic Plastic	Mid-range Plastic
Materials and durability	9/10	3/10	6/10
Certified hygiene and safety	9/10	3/10	6/10
Initial price	6/10	10/10	8/10
Real cost over 2 years	9/10	6/10	5/10
Cylinder freedom	10/10	9/10	4/10
Design and finish	9/10	4/10	7/10
Daily user experience	9/10	5/10	7/10
Real sustainability	10/10	5/10	7/10

The daily user experience: the details that make the difference

The pressure release system

This is a technical detail that seems minor but is noticeable with every use. The Burbujito incorporates an integrated pressure release system that acts automatically and silently before the bottle can be removed. The result is that there are never any splashes or unexpected bursts of sparkling water.

Basic soda makers often omit this system or implement it in a very rudimentary way. The user has to wait for the pressure to drop manually, or risk gas suddenly escaping when removing the bottle. It's a small inconvenience that repeats every time you carbonate.

Mechanism stability

Stainless steel does not have elastic memory like plastic: it does not deform, does not develop play, and maintains the same threading precision from the first day to the last. In plastic soda makers, the bottle's threading mechanism is usually the first part to start giving way with intensive use.

Cleaning

Stainless steel is a non-porous material: it does not absorb odors, does not retain residues, and cleans easily with a simple rinse. Plastic, especially after months of use, can accumulate micro-scratches where bacteria deposit and retain ambient odors.

Who each type of soda maker is for

A basic plastic soda maker makes sense if:

•       You want to try the concept before investing more

•       Your use is very occasional: 2-3 times a week at most

•       You assume you will probably replace it in 1-2 years

•       The initial price is your only decision criterion

A mid-range plastic soda maker makes sense if:

•       You want better design and finish than the basic range

•       You don't mind depending on a single supplier for refills

•       You don't use the soda maker daily or very intensely

The Burbujito makes sense if:

•       You're going to use it every day or almost every day

•       You value safe materials and food certifications

•       You want total freedom to choose where you buy your cylinders

•       You are interested in the Soda Club to automate refills and save money

•       Design matters to you and you want something that looks good in your kitchen without aging

•       You think long-term and prefer to pay more once than little by little many times

Conclusion

All soda makers do the same thing on paper: they carbonate water. But the difference between an uncertified plastic machine and a stainless steel one with LFGB, FDA, and ISO 9001 is real and noticeable in the daily experience, durability, and what you actually pay over time.

The Burbujito is not the cheapest option to start with. It's the smartest option if you plan to use it regularly, want to feel confident about what touches your family's water, and don't want to buy another soda maker in five years.

Scores prepared by Congas based on its own technical specifications and general market characteristics by price category.

 

Frequently Asked Questions

Is stainless steel better than plastic for a soda maker?

For daily use, yes. Stainless steel lasts longer, is more hygienic, does not absorb odors, and maintains its mechanical precision over time. For very sporadic use, quality plastic is perfectly functional.

What does it mean for a soda maker to have LFGB certification?

LFGB certification (German Food and Feed Code) certifies that the machine's materials that come into contact with water do not release harmful substances. It is the most demanding standard for food contact materials in Europe, exceeding the minimum CE requirements.

What is the standard thread for CO2 cylinders?

It is the most widespread connection system in the world for domestic soda maker cylinders. A standard threaded cylinder is compatible with the vast majority of soda makers on the market, giving you total freedom to choose a supplier. There is also the bayonet or quick-connect system, which is proprietary to some brands and only accepts their own cylinders.

How long does it take for a stainless steel soda maker to pay for itself compared to a plastic one?

It depends on usage, but with average family consumption of 60 liters per month, the initial price difference between a Burbujito and a mid-range with a proprietary system is recovered in less than 12 months thanks to savings on refills with the Soda Club.

What is the Congas Soda Club?

It is Congas' subscription service to automatically receive CO2 cylinders at home, including empty cylinder collection. The refill price starts from 13.50 EUR (0.21 EUR/liter). No commitment. More information at congas.es/pages/soda-club.