Are you producing gourmet canned foods and/or prepared dishes? Then you know that pasteurization or sterilization is essential. Without this crucial final step, your products could pose a public health risk and cannot be authorized for sale.

Pasteurization and sterilization, aren’t they the same?

Both techniques are used to preserve food in hermetically sealed containers by eliminating microorganisms and enzymes through heat. However, there are key differences between the two:

• Pasteurization involves heating food to temperatures between 60°C and 100°C for a few minutes or even seconds. Because the process is less intense, it better preserves the food’s organoleptic properties, but it does not destroy all microorganisms. As a result, pasteurized products must be kept refrigerated and have a shorter expiration date.
• Sterilization, on the other hand, exposes canned food to temperatures above 100°C for a specific period of time. While this method is more intense, it completely eliminates microorganisms and spores. This ensures a much longer preservation time without the need for refrigeration, allowing storage at room temperature.

When packaging food, remember that glass jars with screw-on lids require a small empty space at the top. Without this headspace, the container may not seal properly, or could even crack during the process.

Did you know that the pH of food plays a crucial role in its preservation and safety, especially for gourmet preserved foods and ready-to-eat meals?

The pH value indicates the hydrogen potential, or the potential of hydrogen ions, and is used to determine the degree of acidity or alkalinity of a specific food or any other type of solution, based on the concentration of hydrogen ions it contains. Keep in mind that pH directly affects the shelf life of products. It is also a key factor in pasteurizing or sterilizing food, since the degree of acidity or alkalinity determines how many microorganisms can proliferate.

The acidity level is measured according to the principle of “less is more, and more is less.” In other words, the more acidic a food is, the lower its pH value will be, and vice versa. When measuring pH, it’s important to consider temperature, as it can influence a product’s acidity level. In most cases, samples should be taken at room temperature (around 20°C).

Why should you measure the pH in canned food and cooked meals?

Both gourmet preserved foods and ready-to-eat meals combine several ingredients in a single container, resulting in a range of pH levels. That’s why it’s essential to determine the exact acidity of the mixture.

Did you know that pH can vary depending on the variety and ripeness of the food? Take apples, for example, a ripe apple is less acidic than an unripe one. This is important to remember, as the pH of your recipe today might not be exactly the same as the one you prepared yesterday.

Why should you measure the pH of your food or drink?

The pH of food plays a crucial role in the pasteurization or sterilization of gourmet preserved foods and ready-to-eat meals. It determines the exact time and temperature needed to effectively eliminate microbiological and enzymatic activity.

A lower temperature applied over a longer period of time can destroy the same amount of microorganisms as a higher temperature applied briefly. However, this may also affect the food’s smell, color, and taste to varying degrees.

Keep in mind that adding acidifying agents alone does not guarantee long-term preservation. To ensure food safety and compliance with sanitary standards, proper sterilization or pasteurization of your product is essential.

Which food products can be sterilized in a TERRA Food-Tech autoclave?

You can sterilize virtually any product in a TERRA Food-Tech® autoclave, as long as your gourmet preserve or ready-made dish contains a heat transfer medium such as water, oil, or sauce. Examples include:

Meat:
Marinated, stewed, or sauced meat dishes; pre-cooked meals combining meat with ingredients like rice or vegetables; soups; pâtés; cooked ham or chicken breast; beef, chicken, or turkey-based pet food; and even baby food.

Fish:
Tuna, sardines, bonito, and mackerel in oil; fish pâtés; pre-cooked dishes such as salmon or red scorpionfish pie, sea bream with potatoes, steamed fish, or peppers stuffed with tuna and cucumber.

Seafood:
Pickled mussels, natural cockles, scallops with garlic or scallop sauce, baby squid in ink, octopus in olive oil, natural prawns, and pâtés made from king prawns, mussels, crab, scallops, or sea urchin, as well as seafood dishes like paella or fideuá.

Vegetables, fruit, and legumes:
A wide variety of vegetables, fruits, beans, and legumes, as well as soups, jams, and compotes.

Sterilization: a step-by-step guide

Read this article to explore the key steps in the sterilization of canned foods and prepared meals.