Embarking on the sale of natural juices brings with it questions about how to keep the juice fresh and extend its shelf life effectively.
Historically, thermal pasteurisation was considered the main preservation technique to extend the shelf life of juices by reducing harmful micro-organisms by heating the product.
However, depending on the time and temperature of the process, this method could alter the taste and some nutritional properties of the juice. Nowadays, non-thermal preservation alternatives have been developed that largely preserve the organoleptic and nutritional quality of the juice, providing an experience very close to natural juice.
In the following, we will explore the most effective techniques for preserving fresh juice for longer.
Keep the juice fresh with these types of thermal pasteurisation treatments
1. Slow Pasteurisation (VAT) or Low Temperature and Long Time (LTLT):
This technique was the first used in pasteurisation. It consists of heating the juice to temperatures around 63-65°C for a period of 20-30 minutes, followed by a gradual cooling phase. The packaging process, which can be aseptic or non-aseptic, can take up to 24 hours. Nowadays, this method has largely been replaced by other techniques, due to the great change it causes in the taste and nutritional content of the juice. Today, the food industry has adopted more advanced systems that maintain the taste and properties of the juice more effectively.
2. High temperature rapid pasteurisation (HTST):
This method consists of bringing the juice to temperatures ranging from 75°C to 95°C for a short period of time, in the order of 15 to 30 seconds. It is the preferred option in the juice industry, as it slightly alters the organoleptic and nutritional properties of the juice, and is significantly faster than the previous method. Once pasteurised, the juice can be packaged following an aseptic or non-aseptic process, the key difference being the shelf life of the final product.
It is the best pasteurisation option when you have into account the investment, production capacity, process safety and preservation of the organoleptic and nutritional properties of the juice.
3. Ultra high temperature (UHT) or ultra high temperature (UHT):
This process requires treating the food at high temperatures; about 138 °C for a few seconds. It is often used for low-acid products, such as milk, which contain heat-resistant microorganisms. This technique can extend the shelf life of the product by up to six months, even without refrigeration. However, it requires aseptic packaging and considerable capital investment.
Non-thermal juice preservation techniques
The trend in consumer preferences and industry standards is increasingly towards fresh, minimally processed or Cold Press products. For these applications, a multitude of non-thermal preservation alternatives are gaining prominence.
- UV treatment
Its effectiveness is limited in juices with high turbidity, as the impact of the treatment is restricted to the radiation range. However, some companies prefer this method because it does not raise the temperature of the food and therefore causes only minor changes in its organoleptic and nutritional quality.
- Pulse electric fied (PEF)
This method also ensures that the nutritional and organoleptic quality of the product remains largely the same as the fresh version. Although it can sometimes leave a metallic aftertaste, the shelf life is extended by 7 to 20 days when refrigerated.
- High pressure treatment (HPP)
High-pressure treatment consists of submerging the juices, already in their final packaging, in cold water and applying pressure of up to 600MPA for a period of 3 to 6 minutes. With this treatment, premium quality products are obtained with a shelf life of between 30 and 60 days under refrigeration.
HPP technology is an ideal option for small to medium productions, as it can process batches of bottles with different recipes at the same time, and from a single bottle up to the maximum capacity of the machine. The main handicap of this technology is the high initial investment required, although there are companies that rent their services to small and medium-sized producers.
What is the best technique for preserving juice?
Effective juice preservation relies on the choice of several crucial factors, each of which plays a vital role in ensuring both the safety and quality of the final product.
- Type of food to be pasteurised.
- Food safety.
- Required shelf life of the product.
- Production capacity.
- Budget available.
- Impact on the organoleptic and nutritional properties of the juice.
Thermal pasteurisation, being the most common method, offers remarkable efficiency and cost-effectiveness, but can significantly alter the properties of the product. On the other hand, non-thermal pasteurisation, being a gentler method, does not guarantee the same efficiency in the elimination of pathogens and bacteria. Ultimately, the choice will depend on the specific needs and priorities of the production process.
¿How to keep natural juice without treatment?
At Zumex, we understand the value of fresh, natural juice. We know that juice lovers appreciate the vibrant burst of flavour and value the nutritional richness it offers. But how long do these freshly squeezed natural juices really last?
Natural juices, those that have not undergone any kind of treatment or pasteurisation, usually remain fresh for two to three days if refrigerated from the moment they are squeezed. However, this period may vary depending on several factors, such as the freshness of the fruit used, pH of the recipe and storage conditions.
At Zumex, we offer a variety of solutions to help businesses serve fresh and delicious juices to their customers. Whether you are looking for a juice bar juicer, or a cold press juicer, we have the tools and experience to help you.
If you have any questions about juice preservation or are interested in learning more about our solutions, please do not hesitate to contact us. We are here to help you get the most out of your juice business.