Safely planning preserving in kettles and canning

When preserving in a kettle, sealed jars or suitable cans are treated in heated water. Temperature and duration must suit the contents, container, and intended process; blanket values are not reliable. Authoritative sources include recognised preserving literature, container manufacturer specifications, and, for commercial production, professional and regulatory coordination.

We at Beelonia GmbH have been manufacturing boiling and scalding kettles for artisanal, agricultural, and commercial processing in Beelen since 1880.

At a glance

Planning question	Key point
Jar or can?	Only use suitable, undamaged containers and matching closures
Which contents?	Consider composition, consistency, and starting temperature
Which kettle?	Single-walled boiling kettles are intended for cans and sausages
Which process values?	Consult recognised tables and manufacturer specifications
Which batch size?	Plan container quantity, water space, and handling together
Commercial sale?	Clarify self-monitoring, traceability, and labelling

Reading tip: The scalding kettle and butchering kettle guide explains designs and areas of application, while Boiling kettle meat: instructions for butchering festivals and home slaughtering details the boiling process, and Scalding sausages: temperature table, times, and troubleshooting deepens product-related process planning.

How does preserving in a kettle work?

When preserving, sealed jars or suitable cans are treated in heated water according to a defined process. Temperature and duration depend on the contents, container, and complete heating through. Prerequisites are recognised preserving literature, manufacturer specifications, or a professionally confirmed process; roughly estimated values are not sufficient.

The kettle transfers heat to the containers via the water. These must be arranged so that the intended process can be maintained. Available accessories, such as a bottom grid, must suit the container arrangement and workflow.

Jars, cans, lids, and closures are checked for damage before filling. Fill level, closure, and pre-treatment depend on the respective container system. After heat treatment, the containers must be removed and handled in a way that prevents damage to the closures.

Which kettle is suitable for preserving and canning?

Single-walled boiling kettles, sized to match the number of containers and planned batch, are suitable for preserving and canning. Available models range from 80 to 400 litres. The prerequisite is that the containers, heating method, installation, and operating sequence fit together; glycerine kettles are primarily intended for soups and meals.

The sheet steel kettle stove for 100 to 250 litres works with wood, has a fireclay lining, and is the most cost-effective option. Up to 150 litres it is one-piece, from 175 litres it is two-piece. It costs from 1,604.12 € (as of 07/2026).

The Mini Kessel Elektro offers 80 to 100 litres, 8 kW, 400 V, and a thermostat. It costs from 1,804.04 € (as of 07/2026). Larger electric kettles control temperature and time digitally and do not require a chimney connection.

Kettle type	Suitability	Price
Sheet steel kettle stove 100–250 l	Wood, small to medium batches	from 1,604.12 € (as of 07/2026)
Mini Kessel Elektro 80–100 l	8 kW/400 V, thermostat	from 1,804.04 € (as of 07/2026)
Multi-fuel round 150–300 l	Wood, V2A stainless steel (AISI 304)	from 4,812.36 € (as of 07/2026)
Multi-fuel square 150–400 l	Larger batches	from 5,747.70 € (as of 07/2026)
Electric square 150–400 l	Digital control, 400 V	from 8,954.75 € (as of 07/2026)
Glycerine kettle 90–400 l	Soups and meals, not primarily cans	from 2,737.00 € (as of 07/2026)

You can compare designs and heating types in the boiling and scalding kettles category. Water inlet, drainage, footprint, and safe paths for loading and unloading should also be considered in your selection.

What matters when it comes to temperature and time?

Temperature and time must allow for complete heating of the contents according to the recognised process. Key factors include the recipe, starting temperature, container size, and load. Reliable values for each specific product require recognised tables, manufacturer specifications, or professionally tested operating procedures instead of blanket minute estimates.

Density, composition, piece size, and starting temperature influence heat transfer. The material, volume, and fill level of the container also change the process. Therefore, a value for a small jar must not be applied to a larger can or a different recipe without verification.

The water temperature only describes part of the process. Digital kettles can control temperature and time; a core temperature sensor supports suitable measuring tasks. How the relevant product temperature is determined in sealed containers must be professionally defined for the specific process.

Influencing factor	Significance
Contents	Composition and consistency influence heat transfer
Container size	Different containers do not necessarily heat up equally
Starting temperature	Cold and warm fillings start under different conditions
Load	Arrangement and water volume influence the batch
Closure	Only use suitable systems according to manufacturer specifications
Cooling	Follow the intended post-treatment and protect containers

How can preserving be planned for farm shops and clubs?

Preserving in a farm shop or club requires coordinated planning of quantities, personnel, and workflows. The kettle range typically spans from 75 to 3,000 litres. Clear responsibilities are essential; for commercial sales, self-monitoring, traceability, labelling, and the requirements of the responsible food safety authority must also be considered.

The required size is determined by the number of containers per batch, not just the annual volume. Preparation, filling, heating, removing, cooling, and cleaning all require time and space. The slowest work step often determines the practically usable capacity.

Work step	Planning question
Preparation	Are the recipe, containers, and closures available?
Filling	Are there clean work surfaces and standardised workflows?
Loading	Can containers be safely inserted and removed?
Heating	Are processes and responsibilities documented?
Cooling	Are suitable areas available?
Storage	Can batches be clearly labelled?

In clubs, process management and documentation should be assigned to specific individuals. For commercial sales, the food business operator bears the responsibility. The self-monitoring concept according to EU hygiene law, as well as specific requirements, must be coordinated with the food safety authority or veterinary office.

What is important for safety when canning?

When canning, suitable containers, undamaged closures, hygienic work practices, and a defined heating process are required. Every batch must be fully treated according to the designated parameters. A prerequisite for sale is to have any uncertainties regarding the product, can, or process clarified professionally and, if necessary, by the authorities beforehand.

Cans must not show any visible damage, deformed edges, or unsuitable closures. Sealing is carried out according to the specifications of the respective container system. Noticeable, leaking, or damaged containers are sorted out and professionally evaluated.

The kettle, outlet, and accessories must be included in the cleaning schedule. Bottom grids, floats, and water inlets are available via the accessories for kettles. These aids support the workflow but do not replace a defined process management.

For commercial products, procedures, responsibilities, batch labelling, and the handling of deviations must be documented. Specific process values come from recognised documents and should be professionally checked for new products or containers.

When are a preserving cooker or pot sufficient?

A preserving cooker or pot is sufficient if only a few containers are processed and the intended procedure remains controllable. The smaller series compared here start at 80 or 100 litres. The prerequisite is that capacity, temperature control, and safe handling are adequate for the actual batch.

For private or occasional use, compact equipment is often easier to store and clean. A larger volume does not automatically improve process reliability. Container arrangement, water flow, and controlled temperature remain crucial regardless of the appliance size.

A commercial kettle makes sense if larger quantities are regularly produced or multiple batches follow one another in a planned manner. Before purchasing, you should check the container diameter, loading height, removal path, footprint, and available energy.

Which questions frequently arise about preserving in a kettle?

Can jars and cans be processed together?

A combined batch only makes sense if the same professionally confirmed process applies to both container types and all contents. Different sizes, materials, or contents may have varying requirements. Without a suitable procedural basis, jars and cans should be processed separately according to their respective specifications.

Must the water completely cover all containers?

The required water level depends on the container system, kettle, and applied process. A blanket rule is therefore not practical. Recognised preserving instructions and container manufacturer specifications are authoritative; the water management specified there must be continuously monitored and maintained throughout the entire batch.

Is a glycerine kettle better for canning?

No. The glycerine kettle is primarily designed for soups and other meals where the double jacket reduces sticking. Single-walled kettles are intended for sausages and cans. The indirect heating of the glycerine kettle is therefore not a general safety advantage for canning in this process.

What are the advantages of an electric kettle?

An electric square kettle does not require a chimney connection and offers digital temperature and time control. The models are ready to plug in at 400 V and feature a core temperature sensor as well as a safety drain. Connected load, fusing, and operational setup must nevertheless be appropriately planned and professionally checked before operation begins.

Can preserved products be sold in a farm shop?

Commercial sale is only possible within the framework of the business's food law responsibilities. This requires a suitable self-monitoring concept, traceable procedures, hygiene, traceability, and correct labelling. Specific requirements should be coordinated with the responsible food safety authority or veterinary office before production begins.

Sources and professional foundations: Federal Institute for Risk Assessment (BfR); DLG practical knowledge; recognised preserving literature; container manufacturer specifications; food safety authority guidelines.