**8. Conclusions**

In this paper, HS-RT has been presented as an efficient method to preserve fruit juices in terms of juice safety and quality, consumer acceptability, industrial implementation, and environmental impact. Its main advantage over other conventional preservation methods is its extremely low energy consumption. HS-RT could be employed in a wide variety of scenarios: the food industry, ship or truck transport for long distances, school or hospital kitchens, restaurants, or even at home. Moreover, its application in developing countries, where the continuous supply of electric energy is difficult, would be especially noteworthy.

Even though the existing literature analyzed in this paper provides evidence of the feasibility of this method for fruit juice preservation, much more research is still needed. First, HS-RT should be tested on a wide variety of juices obtained from different fruits (e.g., acidic and low-acidic juices, clarified or not, obtained from only one fruit or by mixing a combination of fruit juices and purees) to assess the effect that fruit juice composition can have on quality decay under pressure.

Second, the effect of pressure on the main mechanisms implied in the spoilage of fruit juices should be evaluated in depth. Most existing studies have focused on microorganisms as the main agents responsible for juice spoilage, but the effect of pressure on other degradation agents such as enzymatic and chemical reactions should not be forgotten. In this sense, specific studies to analyze the degradation of relevant compounds (specific vitamins, bioactive compounds, pigments, and so on) under pressure should be designed.

Third, research effort should be particularly focused in identifying issues that could pose a problem for the success of HS-RT such as the adaptation of microbial strains to pressure stress or the pressure-enhanced formation of undesired compounds during storage, among others.

Finally, equipment development for the practical application of HS-RT remains a challenge. Even though pressure tanks do not involve a technological challenge today, their price could be an important limitation. The development of new materials that are able to resist high pressures but are cheaper than steel could help in the industrial success of HS-RT.

**Funding:** This research received no external funding.

**Conflicts of Interest:** The author declares no conflict of interest.
