You need to follow integrated approach

• Follow strict hygienic requirement
• Raw material sterilization
• Low temperature storage
• Vacuum packing as followed by most companies
• natural preservatives such as plant extracts, essential oils, and antioxidants

The question is general and it is different for various types of food. but as you mentioned types of juices, it is based on the type of packaging. For example, when you use aseptic packaging or pasteurization tunnel for drink or use hot filling for canning tomato paste, there is no need to using preservative agent.

Conversely, you have to use preservative when you fill the beverage in plastic pets. in this case, you may be able to reduce the dose of this material by natural ingredients (Vit C, For example).

potassium sorbate

Plant essential oils can be used as natural food preservatives, such as; cinnamon, lemon grass, cumin, coriander, thyme, clove, ginger and jojoba.

If the legislation and regulations of your country allow it, you can use natural preservatives, such as: Natamycin, Nisin, Epsilon-polylysine, etc; citric derivatives such as Citricidal and some antioxidants that also work as antimicrobials, such as rosemary or licorice extract, etc.

For pickle you can use natural acetic acid. I suggest you to minimize the usage of preservatives and try to practice GMP, GHP and use cold storage to retard microbial growth.

Thanks to everybody for the Insights !

You can use KMS

Allow tomatoes to dry and make it fine powedry form use food preservatives like Nisin,Citricidal for long period without contamination.

Salting food as a preservation technique was predominantly used before refrigeration was invented. Just like sugar, salt draws water out of food, dehydrating it. Since bacteria can’t survive without water, they eventually die.