12 myths about preserves

In this post we debunk a large number of false beliefs, stories and myths about the production and consumption of preserves

As with everything else, many unfounded theories have been created around gourmet preserves, without any scientific basis and without any kind of corroboration. Perhaps this is due to old ideas being consolidated and/or to a confrontation of interests within the food industry itself. Whatever the reason, our purpose here is to deny those opinions related to food preservation and preserves that are not true. Do you want to join us?

1. Preserves are not healthy.

This is one of the greatest myths about preserves that is totally false.

Preserves provide nearly the same nutrients and minerals as fresh foods. In fact, some of them are processed after harvesting, thus reducing to the minimum nutrient loss.

Several studies have confirmed that neither proteins, carbohydrates nor fats are affected during the preservation process. The same applies for minerals and fat-soluble vitamins, such as A, D, E and K.

Also, it has been proven that there are certain foods that increase their nutrients when sterilized. An example of this effect can be seen in tomatoes, whose natural pigment (lycopene) with antioxidant power increases with heat treatment.

2. Preserves always contain food additives.

Myths about preserves: preservatives and food additives


Preserves do not always contain substances to prevent chemical or biological alterations in order to preserve or improve their freshness, flavor, texture or appearance. And those substances are not always necessary for 2 important reasons:

  • Sterilization eliminates almost 100% of microorganisms, spores and enzymes, thus preventing food deterioration.
  • Since preserved foods are hermetically sealed, oxygen is prevented from entering and contamination is avoided.

3. All additives are artificial, not natural at all.

This is another false belief. Not all preservatives and additives are artificial.

These substances can be produced by synthetic means, but they can also be obtained from plants, animals or minerals. And today, food industry is increasingly turning to natural or organic preservatives and additives.

It should be mentioned that, depending on the function they perform, additives are classified as: antioxidants, colorants, stabilizers/thickeners/gelling agents, acidulants, preservatives, etc. And, according to their method of production, they are classified as:

  • Natural additives: those obtained directly from nature, they are oftein obtained from plant extracts. Here we find additives such as pectin, of vegetable source, and agar, obtained from algae.
  • Synthetic additives: the non-natural ones, those obtained in laboratories and industrially produced, which may or not may be present in nature. Most preservatives are artificial, such as:
    • Benzoic acid: ideal for acidic pH foods and liquid products, such as soft drinks, sodas and other beverages.
    • Sorbic acid and its salts: they can be obtained both natural as well as synthetic ways.
    • Potassium sorbate: used especially for wine preservation.

4. It is impossible for a preserve to have a long shelf life without incorporating additives in its formula.

Another great myth about preserves that is simply false, it is not impossible at all.

As we have already explained above, sterilization and hermetic sealing prevent a preserve from deterioration and contamination.

It is true that gourmet preserves can have an expiration date that ranges from 12 months to 5 years. This is due to the heat treatment those products are exposed to. Sterilization, unlike pasteurization, eliminates basically all microorganisms. Therefore, it is not necessary any refrigeration once a product has been sterilized. Pasteurized products, on the other hand, do require refrigeration immediately after heat treatment because, as they are treated at a temperature below 100ºC, some microorganisms are still alive, and the products have a much shorter best-before date.

For more information, you will find a detailed comparison of sterilization vs. pasteurization in our Blog.

5. Additives are harmful to health.

Again, it is another false myth about preserves.

As you can see, additives perform several useful functions in foods. They are identified by a number preceded by letter E, which means that they have been approved in Europe by the Joint FAO/WHO Expert Committee on Food Additives (JECFA), which is the international body responsible for safety evaluation regarding food additives.

Food additives are not harmful if they are consumed in small quantities. A food additive is determined to be safe for human consumption based on an estimate of a quantity of such substance in food or drinking water that a person can ingest on a daily basis over a lifetime without posing a significant health risk.

6. Experts recommend that preserves should not be part of our diet.

This is also a common false belief about the consumption of preserves.

Nutritionists and dieticians advise that our diet should not be based exclusively on preserves. However, they also say that there is nothing wrong with including them in our menu from time to time. In fact, preserves can become our best ally when it comes to cooking, saving us both work and time. However, a balanced diet should be maintained as long as it is based on consumption of cereals, preferably whole grains, as well as fruits, vegetables and legumes.

7. Eating too many gourmet preserves can lead to botulism.

Once again, this statement is false.

Gourmet preserves are produced under strict food safety and quality standards. To avoid any kind of risk, these products must be sterilized with professional equipment that guarantees the treatment has been 100% satisfactory. So much so, that with a TERRA Food-Tech® autoclave you can rely on continuous monitoring during each process to indicate whether it has been carried out correctly.

Botulism disease is caused by the toxin produced by Clostridium Botulinum, one of the most dangerous pathogens for our health, which is characterized by its resistance to high temperatures and its ability to grow and remain inside a preserve without needing oxygen. Therefore, to completely eliminate this bacteria from a preserve, an internal temperature of 121.1°C must be reached for more than 3 minutes, or an equivalent heat treatment must be carried out, i.e. less temperature, but during a longer period of time.

Botulism outbreaks are very rare, although they can occur, especially in cases of homemade preserves. Therefore, we advise you to discard any homemade preserve that has a strange color or smell when opened.

8. Artisan preserves from small producers are not safe.

Myths about preserves from small artisanal producers

This is a big misconception. All food companies, regardless of their size, are subject to the same control system and their products must meet the same health requirements.

We should not confuse homemade preserves, made at home without specialized equipment, with artisan preserves, made by micro-entrepreneurs, small local producers, restaurants and small-scale farmers.

In order to be marketed, artisan preserves must undergo professional pasteurization or sterilization, which is based on using automatic and professional equipment that strictly complies with current health and hygiene regulations. Therefore, they are just as safe for consumption as industrialy preserves.

9. The best before date is the same as expiration date.

No, they are not the same.

Highly perishable products in which pathogenic bacteria or parasites may be present, such as raw and fresh meat and fish, should include an expiration date, which indicates that such foods should not be consumed after that expiration date. The reason is because those foods may be in bad condition, damaged or even have developed microorganisms that are dangerous to health.

However, the best-before date is intended for those products that are more durable and stable. Once the consumption period has passed, foods may have lost some of their properties, having less of their distinctive smell and/or a slightly rancid taste, but without microbiological danger if container integrity is protected.

10. If the container of a preserve has suffered some kind of blow, it should not be consumed.

Myths about preserves: packaging

This is not entirely true. We clarify this in order to avoid confusion.

During the design and production processes of cans, it is verified that the gauge and temper of metal sheets can withstand normal handling or even small blows. Therefore, in the case of slight dents, both food safety and package tightness continue to be maintained.

However, it is strongly recommended to avoid consuming preserves when their containers are punctured or if cans or lids of glass jars are bulging or swollen, which means that oxygen may have entered and its contact with those products will trigger their degradation.

Therefore, it is advisable to consume preserves as long as their containers are kept in optimal conditions.

11. Tin cans contain lead, which is not only toxic, but also affects the taste of food.

Today that is not true. This statement was valid when steel or tinplate cans were used and soldered with lead, a procedure that is currently prohibited due to its toxicity.

Currently, food cans are made of steel or aluminum, with an inner coating based on harmless sanitary varnishes and lacquers in order to prevent food contact with metal sheets and thus avoid migration of metal traces into products. In addition, these cans are hermetically sealed by electric welding. All these features guarantee that the flavor and quality of canned foods are fully preserved.

12. Once preserves have been opened, they should be stored in another container.

Another false myth about preserves that is not entirely true, especially nowadays.

In the past, the products had to be kept in another container because cans were made of steel or tinplate and could rust, but nowadays cans are made of aluminum and do not require soldering.

It is highly recommended to transfer foods to another container if the original packaging cannot be resealed in order to avoid possible external contamination or oxygen ingress. For this reason, some cans now incorporate plastic lids, so that the product can be consumed later on if it has been opened.

More information about gourmet preserved food

Myths about production and consumption of gourmet preserves

If you are as passionate about the world of gourmet preserves as we are, in our blog you will find interesting articles about which foods can be sterilized, available preservation methods, tricks to avoid changes in gourmet preserves or ready meals when sterilizing them or the steps you need to follow to start your own gourmet preserves and ready meals business, among other contents.

Also on our website we offer you some experiences of our customers who, through their success stories, tell us how and why they decided to dedicate themselves to the production of gourmet preserves.

Also, if you have any questions regarding this matter or need guidance, just ask us. Contact us and we will help you!

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