Freeze-drying is a process that removes moisture from a product by vacuum pressure. With that said, every product has a different moisture content. There is no "set time" for freeze drying and it takes trial and error to pinpoint the exact times for your product. Times will all be dependent on how much product you're doing at one time, how large the product is, humidity in your facility, freezing times, etc.
Fruits are typically a higher moisture content product and can take as little as 10 hours for a lower moisture product like bananas and more time can be expected for higher moisture product like grapefruits or oranges. Believe it or not, there is a lot of moisture in vegetables too and they have a broad range of dry time as well. The shorter being items that don't require a lot of prep time as well, like lettuce or leafy greens. This also applies to things like herbs and other plants, i.e., flowers, greens, etc.
The popular freeze-dried candy craze is a huge topic for discussion right now, how long will it take to make some fun, fluffy candies? You can expect anywhere from 12-20 hours. These items, although a lot of fun can be a little touchy with what will work and what will not. Candy like skittles and starbursts are easy and fun but stay away from chocolates buttery candies, these items do not freeze dry well due to their fat and oil content.
The bottom line of batch times is they will never be a constant number. There are many factors that can affect the products and how well they turn out. Humidity, vacuum seals, how cold was your item prior to freezing, number of items you're freeze drying. There is no definitive answer for you. Freeze drying will take a lot of trial and error before you pinpoint your exact recipe for what you're making. So, Parker Freeze Dry can't give you an exact recipe or answer to this question, this is a good starting point! What we can say about Parker Freeze dry is with the ability to control the machines and the quality of the materials used to create the Parker line, you can achieve lower pressures, lower temperatures and faster processing times. We aim to achieve a 24 hour or less process time for all products that enter the Parker Freeze dry chambers, this can typically be achieved by altering your changeover times and defrost times.
We also offer test runs- if you are interested in scaling up from your tabletop operation, but you're unsure how a large quantity would run we can run it here at our facility.
Reach out for a test run!