F. A. Q. for the use of future professional canners

What is pasteurisation?

This is a method for the preservation of foodstuff for which the latter is heated to a defined temperature and period of time before being cooled rapidly.

Pasteurisation significantly reduces the number of microorganisms in the pasteurised product, but some pathogenic forms are resistant (such as spores). This is why it is important to keep in the cold the pasteurised foods to prevent the growth of bacteria that have not been destroyed.

Pasteurisation differs from the U.H.V. method used for the treatment of milk where heat alone plays a role in the destruction of microorganisms.


What is sterilisation?

This is a technique intended to eliminate all microbial germs of a preparation by bringing it to a high temperature (more than 100 °C) for a period defined according to the product treated before being cooled rapidly.


What is canning?

Canning is a method of food preservation that consists in placing them in containers (cans or jars) which are made airtight and which are then heated to destroy the contaminating microorganisms. The temperatures to be reached according to the produced products are between 110 and 120 °C.

The foodstuffs that can be canned by subjecting them to high temperature are vegetables, meats, seashell fruit, poultry, and dairy products.

The only foodstuffs that can be canned in a boiling water bath are those that are naturally acidic such as fruit, some vegetables (pickles, for example) or other to which was added an acidifier (vinegar), or oil, or alcohol.

A well-made canned product, by applying appropriate scales for each product, allows long time conservation without refrigeration constraint, that is to say, it can be stored at room temperature.


What is placing into vacuum?

It is a technique that reduces the amount of air, hence the action of oxygen in a canned product.
It is not, in any case, a preservation technique; it must be considered - at best - as a method of extending the life of fresh products in a refrigerated environment at a constant low temperature. Failure to comply with this provision may result in adverse health consequences.

Techniques of sterilisation and pasteurisation:

The only form accepted - in principle - by the health services, is the use of an autoclave steriliser in compliance to current standards and EC marking.


What is an autoclave?

An autoclave is a thick-walled with hermetic closure container designed to provide under pressure (of a few bars) the cooking or the sterilising water steam or water.

Autoclave is called a cycle using an autoclave and to autoclave is the verb.

In what does the mandatory equipment of an autoclave consist, intended for the manufacture of canned products?

The European Directive (DESP 97/23/EC) requires that each device is equipped with:

- a reading thermometer;

- a recording thermometer, or any other method of recording allowing to check the sterilisation cycle;

- a manometer allowing to monitor pressure;

- a cooling system to proceed with immediate cooling of the canned products.


Power/energy of autoclaves:

Our KORIMAT autoclaves can be supplied by electricity, gas or fuel (for the 240 litres)

We give you, as an indication, the consumption for each capacity:

a) Korimat 120 litres:

- Water

- Electricity

- 380 three-phased - 9 kwh

b) Korimat 240 litres:

- Water

- Natural Gas: 3 m³/h – Liquefied Gas: 1 m³/h

- Electricity

- Fuel: about 2 kg/h

Periodic inspections:

All owners of an autoclave must comply with the following checks:

- Every two years, inside and outside inspection of the tank by a certified organisation

- Every ten years, complete check and re-test by a certified organisation (otherwise, the operating license can become void)


What energy form to choose?

You are, of course, free to choose your energy and we know that in some places, sometimes there is only one possibility.

However, we take the liberty to recommend to you using electricity for several reasons:

- Easy installation, many fewer constrains than for gas and fuel, no need for high and low ventilation

- No unwanted heat in the laboratory.

- Possibility to programme your device for night use at reduced rates.


What autoclave capacity to choose?

This is the question.

But our choice is limited deliberately.

4 capacities: 60 litres, 120 litres, 240 litres or 380 litres.

You must determine the number of jars to treat at one time, and their capacity.

In a 120 litres autoclave, you can, for example, sterilise:

- 110 jars of 250 g

- 45 jars of 950 g

In a 240 litres autoclave, you can, for example, sterilise:

- 220 jars of 250 g

- 90 jars of 950 g


What about sterilisation schedules:

Each canned product retains a time/temperature schedule. Call us and we will discuss this with you.


Can a jar be heated in the microwave?

Generally speaking, no, but the WECK jar, without metallic element after sterilisation, allows you without any worries to heat your jar in the microwave: ease, time saving, and energy saving! However, do not forget to open it before passing it in the microwave.


How can I be sure that my canned product is well sterilised?

When a product is properly sterilised in a WECK jar, the outer tab is positioned downwards; it is a visual and effective stage to ascertain, just by a glance, if your canned product is perfectly successful.


Any other questions?

Do not hesitate to call us; we will be glad to give you the answers.

Call us or send us an e-mail at

F.A.Q. on home sterilisation

What is the different between home sterilisation and professional sterilisation?

The housewife usually does not have an autoclave steriliser to prepare her canned products; she uses an old-fashioned "gas-ring", that is to say a household steriliser. With these devices, the maximum temperature reached is 100 °C.

The basic element for a good canned product will be sterilisation time. It will be necessary to extend this time in order to destroy most bacteria, fungi and microorganisms.


How to place efficiently the jars into a home steriliser?

It is very simple! Just follow the directions of the drawing here on the left. The parts in blue stand for water, those in green for your full jars.


What precautions must be taken to prepare a good canned product?

First of all, good products!

Then, a perfect hygiene of the jars, the lids and clean gaskets

Finally, follow sterilisation time.

Can we sterilise everything?

Yes: meat, game, pâtés, potted meat, foie gras, vegetables, fruit, soups, stewed fruit, jams and even cakes.


Should we "sterilise" the jars before a sterilisation cycle of products?

No! This is a long-time heresy conveyed from grandmother’s recipes; a short reflection makes you realise that the jars do not have to undergo sterilisation before being filled. This step would be useless, since at the very moment they would be out of hot water and placed on a kitchen table they would cease to be sterile any longer!

They just have to be clean; simply wash them in warm water with any household product and wipe them: in this way they are ready to be reused. Once filled, the jars will be sterilised with their content.


Can you use any type of jar?

Yes, of course, provided that it is a jar intended for sterilisation; do not use jars for decoration reserved for food use. If you reuse a jar, the gasket (or if need be, the capsule) must be absolutely new.


Should we boil the empty jars before sterilisation?

No! Just make sure you wash them. Given that once full, you will sometimes boil them even for more than one hour, it is completely unnecessary to sterilise them beforehand. They will sterilise at the same time as the food they contain!

Should we boil the gaskets of the jars?

Not in principle, unless the manufacturer specifies otherwise and which must appear on the packaging. In the case of WECK gaskets, they are in natural rubber and must not be boiled before sterilisation. The gaskets are not reusable, just as the capsules, which must be changed for each sterilisation. Each brand of jars markets the gaskets which adapt to the jar. So that, the WECK gaskets must be used ONLY on WECK jars.

If you use other brands of jars such as Mason, or Le Parfait, refer strictly to the rules recommended by these brands.


Can jars be reused?

Of course! We can, provided that it is mandatory that the gasket or the capsule is changed, and that the jar has no impact or crack.


Should the jars be allowed to cool with their water of sterilisation?

NO, never! This also is a misconception; the sterilisation principle consists in a smooth rise of temperature, a step by step sterilisation and a fast cooling; the jars must therefore be removed from the hot water immediately at the end of sterilisation and if possible cool them with a jet of cold water; the faster they will be cooled, the better they will be preserved.

If you leave your jars to cool in water, there will be proliferation of bacteria in the water.

How to make sure that a canned product is successful?

When the jar is cooled, test it by trying to open the lid; this must oppose a natural resistance.

Can we avoid botulism using a household steriliser?

Of course! Botulism is due to a bacterium that is destroyed at high temperature (from 80 °C to 90 °C).

If therefore, you rigorously apply sterilisation schedules that have been given to you, you will have no problem.

What are botulism and the Clostridium botulinum?

Clostridium botulinum is a bacterium responsible for botulism. Clostridium botulinum is a spore-producing bacterium which is the bacterium resistance form. This spore can withstand low heat treatments (for example, pasteurisation) and sprout (that is to say to give a metabolically active cell) which can cause problems in food security.

It secretes one of the toughest toxins in the animal world. Active by ingestion, the toxin spreads then in the body and acts by blocking intramuscular transmission: it inhibits the motor neurons of the muscular contraction. It is then said that the toxin causes a generalised flaccid paralysis (in contrast to tetanus toxin which inhibits the inhibitory neurons of the muscular contraction, thereby inducing a generalised spastic paralysis). This infection can lead to death by respiratory paralysis of the muscles if no treatment is established. There are three forms of human botulism: food induces botulism (ingestion of preformed toxin in food), infant botulism (colonisation of the intestine by the bacterium) and wound botulism. Intoxication often follows the consumption of badly sterilised canned product or home salted ham. The toxin is heat labile and simple cooking by boiling is enough to prevent risks.

The toxin is resistant to gastric acidity but is heat labile (destroyed around 80 °C to 90 °C): it follows that if a suspect food is heated to boiling just before consumption, any danger disappears.

We therefore warn you against the "advice" given on certain foreign sites, mainly Canadian and Northern American, who recommend use of a pressure pot autoclave to escape botulism. These devices are not to EEC Standards or to NF Standards. Consequently, you remain sole responsible for the purchase and of their use. If you choose to purchase this type of product outside the EEC, we can only strongly encourage you to follow the advices and recommendations of the manufacturer.

For these reasons, MCM Emballages chose not to market this type of devices, preferring to continue using the printed EEC markings.

These small devices of the Presto type are of common use in North America. Do not hesitate to get information from the seller before the purchase.

(By definition, in France, an "autoclave" means a device reserved for industrial and professional use. The designations and Standards vary by Country.)

If you wish to invest in an electrically equipped device, a WECK household steriliser or another brand, this is perfect! If you prepare a little canned product, it is not necessarily useful to invest in this type of device. For home sterilisation, all you need is a large all-work pot and a kitchen thermometer.


Filling rate of jars?

A jar must never be overfilled; about 80% of the capacity of the jar is calculated (depending on the density of the product).

Example: In a 370 ml jar can be placed 300 grams of foie gras, but not more than 250 grams of potted meat. We must also think that some products, such as the very fat products (potted meat, pâtés) expand in the jars. Asparagus and onions contain gasses. It must therefore adapt the rates of filling the jars depending on the products to be sterilised.


How does the WECK process work; what happens in the jar?

During the WECK sterilisation process which has carried out tests for the past 10 decades, two very simple natural laws, that are not possible neither to modify nor to improve, occur simultaneously.


First law:

The normal and natural rotting of fruit, vegetables or meat is caused by microorganisms, very small living beings (for example fermentation germs, bacteria, mould spores, etc.) which are present in great numbers in foodstuffs but also in air. During sterilisation, all these microorganisms which are in the closed jar with the lid, the rubber ring and the clamps, are killed by the action of heat.

Second Law:

The lid and the gasket are fixed firmly on the jar thanks to the strength of the clamps, work at the time of heating of the jar as a pressure relief valve, that is to say, they release from inside the jar air, steam, and possibly also a small amount of liquid, but do not allow to penetrate into the jar neither external air or boiling water. The cooling which takes place after the sterilisation process creates inside the jar a depression (a vacuum) and the normal pressure of the external air thrusts the lid naturally on the edge of the jar and the interposed rubber gasket and ensures airtight and durable closing of the sterilised jar.

The stainless steel clips needed during the sterilisation process have now become superfluous and must be removed after cooling of the jar. They will be reused for all future sterilisations.

1/ Jar ready for sterilisation

The lid with the gasket is placed and fixed by using two stainless steel clips (neither more nor less, as 3 or 4 clips would exert too much pressure on the lid and the gasket;  the air vacuum would therefore not be made properly).


2/ Jar during sterilisation

The inside of the jar swells under the action of heat. A depression happens in the jar. The clips release air, steam, and possibly liquid only from the inside to the outside and not vice versa.

3/ Cooled jar

A depression (vacuum) now reigns in the jar. The normal pressure of the outside air pushes the lid on the jar, which is thus closed hermetically. The clips have become superfluous and must therefore be removed to be reused later.


Here is how to close properly a WECK jar:

1. Turn the glass lid so that the characters and the emblem of the WECK strawberry are visible from inside, that is to say, backwards. Place the gasket on the circular edge of the lid.

2. Push the gasket with your finger onto the lid perimeter of the edge.

3. Turn again the lid and place it with the gasket face down on the jar.

4. Place the WECK stainless steel clips on the reinforced part of the lid. Push the tab of the clips downwards until they snap below the projecting edge of the jar. To remove the WECK clips, simply pull the tab upwards.

5. The Figure shows the correct position of the clamps.

6. Close the jar with two WECK clips. Place them face to face.

7. It is thus possible to stack the new WECK jars and their lids in a stable and compact stack.

8. If you use the new WECK clips, you can place simultaneously in a WECK steriliser 14 one-litre rounded edge jars, or 21 half-litre rounded edge jars.

Why clips have to be absolutely removed when the jars have cooled after sterilisation?

Because the natural closing force exerted by the external air pressure now replaces completely the spring pressure exerted by the clamps, which have, consequently, become superfluous. If you leave the clamps, you will not be able to control at all (by trying to lift the lid) whether the jar has been sterilised and closed correctly. This very simple check of the closure, but so important for the housewife, by the so-called test "of raising the lid" moreover is not possible when you use for sterilisation jars fitted with screw closures, thread closures, eye ring closures of the old style beer bottle closures, or closure devices similar to mechanical action closure.


Is there still another reason foe which WECK does not supply for household use sterilisation jars equipped with mechanical closures?

Absolutely, and this reason is fundamental: your own safety.

If the contents of the jar go mouldy for any reason, the fermentation gases forming inside the jar must be able to lift the lid so that it no longer makes a single body with the jar. This warning signal is so apparent that it is the best way to protect yourself and your family against the risk of unknowingly consuming products that may be sterilised and possibly rotten and falling victim to health problems and even affection.

To what are due the causes of sterilisation failures?

  1. To technical defects:

a) The jar, the lid, or the rubber gasket may have slight defects, or deterioration, that you did not notice before.

Such jars usually open already when cooling or very soon after. Their content is then still good and can be consumed immediately or be re-sterilised by following the temperatures indicated in the recipe after having replaced the damaged parts.

b) The universal clamp is not placed correctly or its elastic force weakened. Such jars open already at the end of sterilisation.

What do you do?

c) The lid or the jar splits (very rarely) during sterilisation or during cooling (often the reason is that the jar had already a weakness in the glass before sterilisation or that the jars were subjected to an important thermal shock).

2. When the gasket no longer plays its waterproofing role:

a) The sterilisation ring (the gasket) was certainly of good quality, but it was not placed correctly; or it displaced from its position during sterilisation under the action of pressure caused by the overflow of the jar (this was only possible for old sterilisation jars but is no longer with the new rounded edge WECK jars).

b) During the sterilisation of meat, sausage and salami, it may happen that due to overcooking or too full cooking, hot grease overflows from the jar at the level of the rubber ring under the action of pressure. The hot grease attacks the rubber ring and can cause bad closing since the jar, the lid, and the rubber gasket stick together.

What do you do?

When the jars open immediately during cooling, proceed as described above. When the opening has not taken place or was noticed only later: extreme caution, especially for meat, sausage and salami. It is mandatory to throw away the content.

3. When mistakes are made during sterilisation.

Temperature and/or time required for sterilisation have not been met or the thermometer indication was not accurate so that all the bacteria have not been killed in the jar. After only a few days or weeks, the gases produced by the decay appear and eventually lift up the lid.

What do you do? Extreme caution. The rotten content must be thrown away.

4. It has defects affecting the product to be sterilised:

a) When the fertilisers have been applied inappropriately, for example, a too massive dose, or too late. This only happens generally for vegetables.

b) When the maturation has taken place in abnormal weather conditions, such as rapid maturation as the result of an intense summer heat, or maturation in damp weather following a long rainy period.

c) When, during harvest or transport, the fruit and vegetables have been left too long in the sun and that, as a result of this exposure, they have already started to ferment a little.

Use of products to be sterilised subjected to the outlined conditions in these three cases above are always a risk and, according to the situation, time and sterilisation temperature must be widely extended or increased.

When such jars open during cooling, consume the content immediately. If they open further, it is mandatory that you throw away the content.

d) You did not realise that the fresh product contained moulds and spores that are usually killed at 100 °C. These multiply in the closed jar as long as the oxygen remains in the upper part and a more or less extended mould plate is formed.

In recent years dieticians found that, in such cases, it is mandatory to throw away the whole contents of the jar because the toxins resulting from the stagnant mould in the juice are very dangerous to health and can cause serious ailments.

Finding and warning

When, during a test of lifting the lid or later at the time of consuming, you find that a lid is not any longer firmly fixed to the jar, it is always a clear and obvious warning signal!

Extreme caution, especially for vegetables that contain albumin, such as beans and peas, but also for meat, sausage and salami since initially corruption of those products is not necessarily perceptible by the human taste and smell, but nevertheless the risk of fatal poisoning is real. Do not consume in any case the contents of these jars.

If, for sterilisation, you use jars equipped with different closing systems, for example also jars of industrial canning reuse, remember in the interest of your personal safety: only jars which are closed under the action of external air pressure, that is to say, jars treated with the proven WECK method, give this warning signal of the detached lid. Jars equipped with mechanical closure do not give this warning signal or at least not in such a clear and conspicuous way so that it can be seen even by children or untrained persons.

Extraction of vegetable juices:

Just like fruit juices, vegetable juices contain nutrient elements, vitamins and valuable mineral salts and therefore exert a beneficial action. Vegetable juice can be drunk, but they are also well suited to flavour and enrich soups and sauces.

Each new harvest year provides an opportunity for many households to store healthy and natural juices. And it is much easier to do than you think! As for marmalade, the operation takes place in two steps: first, extract the juice; second, keep the juice.

If you use very ripe and sweet fruit, there is no need to add any sugar. After the first cooking, the juice is completely sterilised while retaining its nutritional value such as mineral salts, vitamins and its taste.

This method, among the most convenient, allows you, especially if someone gives you a hand when filling and fast closing of the jars, to make in an afternoon more than a hundred jars containing very healthy and nutritious juices of apples, grapes, etc. In short, top quality canned products, really unparalleled!

Extracting of juice with the WECK steam extractor

In recent decades, steam juice extractors have not ceased to be subject of various improvements. The latest is a lid of the WECK Company that simplifies the device: only two easy to place components in the WECK automatic steriliser. Extraction time is least, yield is higher and the quality of juice better.

The WECK juice extractor

The steam juice extractor is perfectly suited for quick and successful extraction in the WECK sterilisers.

The device consists of two parts:

1)     juice tank

2)      fruit container

Of convenient format, easy to wash, easy to use, very durable and food graded plastic, withstanding the heat and acidity of fruit, perfectly neutral with regard to tastes and smells. The enamel antacid layer excludes any colouring of the juice and does not transmit any taste of the metal. If you only place the fruit container in the steriliser, then you have a very spacious steam cooker for potatoes or vegetables.

How does the WECK steam juice extractor work?

The water is boiled in the steriliser (1). The steam thus generated rises in the juice tank (2) steam nozzle (4). This steam creates a pressure under the fruit container (3), it then enters from the bottom pierced with small holes to reach the fruit (vegetables, or herbs). The steam pressure is such that the juice flows from the squeezed fruit, it passes through the fruit container (3) screened bottom to fall into the juice tank (2) and there it accumulates. All germs and bacteria contained in the fruit and the juice are killed by steam. Thanks to the steam nozzle (4) and the excellent heat insulation of the device, almost an integral part of the steriliser (1), the extraction process, is so fast that juice retains all its flavour, its nutritional value, and its vitamins.


Sterilisation of meat dishes is definitely more complex than the sterilisation of fruit and vegetables. While for fruit and vegetables only two factors must be taken into consideration, namely the high quality of the product and its detailed treatment and compliance with the instructions during sterilisation, a third factor also plays an important role for the sterilised meat dishes: their thorough cooking before their actual sterilisation (boiled, roasted or braised meat).

The golden rule of meat sterilisation is as follows:

The meat must originate from healthy, well fed animals. It must be fresh, but also have rested long enough.

If the slaughtered animal is old or artificially fattened, the more its meat has connective tissues, and the more it is tough. After removal from cold storage, first of all it must not stay too long in a room, especially if the room is hot. Conservation in a freezer or in a cold room is not always advisable. In these rooms sometimes are formed scents and smells that permeate adversely the boiled or roasted meat but mainly affect the taste of raw meat. Above all, care must be taken not to place the meat directly in contact with other foodstuff that have a strong smell, such as cheese for example. Attention: it must also be avoided to place the meat directly on ice; it becomes "sticky" and loses all its substances. Game that was not treated properly after hunting or which is no longer fresh has an unpleasant smell slightly rancid and is no longer edible.


Good quality meat, which meets the above criteria, can be sterilised in different ways so that it remains well juicy and tasty and may be later used for preparing various dishes. To prepare canned meat, 12 special rules must be followed. To obtain ample information on applications and recipes consult the WECK book.


Sterilisation of cakes

Preparing cakes in canning jars to be sterilised, that is to say “cooking" in the steriliser, allows preserving them without any problems for more than 6 months. In this way, at any time you can surprise your friends who come unexpectedly for coffee by offering your cake confection.


For preparing cakes in canning jars to be sterilised, the WECK brand straight jars are those that are the best suited because only these jars allow easy removal or release of the cake from the jar. These jars come in different sizes.

The inside of the straight or conical jars is well greased and sprinkled with grated almonds or breadcrumbs to ease sliding of the cake out of the jar at consumption.

Any dough is suitable for sterilisation. For the dough to rise, fill the jar just halfway. Since it is required to ensure that the edge of the jar remains completely clean, use for filling the very practical WECK funnel because it covers the entire edge of the jar. 

We can now face the stage of actual cooking. There are two different methods that we detail in key recipes 1 and 2 and that we use in cake recipes. For full information on applications and recipes, consult the WECK book.

Sterilisation for diabetics

The sterilised products are perfectly suitable for diabetics. Thanks to saccharin, or any other sugar substitute, you can sterilise the products according to your taste and adapt them to your personal health needs, that is to say, to your limits. In principle, you can simply refer to all the recipes contained in this book and replace the quantities of sugar mentioned by saccharin or any other sugar substitute. For saccharin, you can refer to the table of equivalence.

Important Note:

During the preparation of jams, marmalades or jellies - and if you apply the sugar/fruit ratio of 1/1 - adding of sugar has a preservation effect. But jams, marmalades and jellies based on saccharin or any other sweeteners require the addition of a conservation product if you wish to keep them in jam pots or jars with screw lid. You can avoid adding this artificial conservation product by meeting the WECK recommendations (see pages 48 and 49 "placing in jam pots or sterilise"), namely sterilise your valuable dietary marmalades 10 minutes at 90 °C in these jars to be sterilised with glass lid and rubber ring, the safest indefinite canning way.


The recipes for diabetics presented below (2 compote recipes, 2 jam recipes and 2 cake recipes) are given by way of example to show you how to adapt the other sterilisation recipes in recipes for diabetics.

Marmalade, Jam, Jelly

• Firstly, distinction must be made among marmalade, jam and jelly.

Under this order, is called "marmalade" any citrus based preparation (for example oranges, lemons, grapefruit, tangerines, etc.) while "jam" is assigned to any preparation of other fruit, no matter whether they are of the same kind or not, whether whole or in pieces.

The notion of "jelly" remained to refer to any preparation containing real fruit juice of one kind or a combination of various kinds, regardless of whether citrus or other fruit.

Whereas the WECK recipes book is commonly used in schools, we have decided to comply with the new nomenclature and we shall now talk about orange marmalade, grapefruit marmalade, cherry jam, blueberry jam and blackberry jelly, lemon jelly, etc.

• Some basic concepts on preparation and preservation:

Marmalades, jams and jellies are made after having prepared the fruit or extracted the juice and then having placed them on the fire with a large quantity of sugar and cooked them for a long time. As soon as this cooking has allowed reaching the desired viscosity, the preparation is complete. A second question that arises is to know how you will make this marmalade (jam or jelly) specific to the conservation of the simplest, the most effective and safest possible way.

For a broad explanation, we refer to the WECK book. You will find recipes that will help you preparing for the sterilisation of all kinds of vegetables, fruit, meat and pastry with individual times and temperatures. The function of the automatic and centrifugal pots is well explained with clear photographs.


• With this basic recipe, you can also make marmalade or jam for diabetics. Take to this effect sugar for diabetics sold in health food stores, and, if you treat poor pectin fruit, add additional gelling additives, also available commercially (follow the directions on the package).

• One last tip: to sterilise marmalade (jam or jelly): choose by giving preference to small jars, and always cover the opened jars placed in the refrigerator, especially when they contain marmalade with the WECK lid which keeps food fresh and lose the least possible amount of flavour and prevent that your marmalade does not feel the refrigerator.

Some tips for the sterilisation of vegetables.

Before talking about the different varieties of vegetables, we would like to particularly underline that it is preferable to sterilise only impeccable vegetables, of good quality and freshly harvested. If you follow the advices and the instructions, success is guaranteed. You should under no circumstances use for sterilising too old, dried, treated vegetables that are no longer impeccable, because they may have already begun to ferment and it is therefore no longer possible to fully guarantee the success of sterilisation. Do not store damp or wet harvested vegetables, but treat them immediately since they can start fermentation very quickly.

Remove generously brownish spots, dried and withered leaves or other bruises so that only quality vegetables go into jars and that your efforts are also rewarded by the excellent quality of the sterilised products.

Not all varieties of vegetables are suitable for sterilisation, especially those with a strong taste or smell which must also be eliminated when prepared fresh by blanching and throwing away the first cooking water. These concern primarily certain varieties of cauliflowers, potatoes and partly kale. The reason may as well be related to the variety but also an application of excessive doses of fertiliser. Spreading of too powerful manure fertiliser or nitrogen fertiliser compromises the taste. A general rule which is also applicable is that, during the placing of the jars, the water in the steriliser is at the same temperature as the content of the jars. It must not be too hot, otherwise the thermometer shows too quickly the required sterilisation temperature, although the latter is not yet reached inside the jar. This reduces the required sterilisation time, which can lead to failures, but can also influence for sure the quality of the sterilised product, whether cooked at the right point or not. This is why you must comply with the indicated sterilisation time.

How to be well informed?

By contacting us at

Trust the professionals whose job is canning for over 25 years!

See you soon.

The MCM Emballages team