Category Archives: Freeze Dried

What Does “Freeze Dried” Mean?

You may have heard the term “freeze dried” and wondered what exactly it meant.  You have probably seen freeze dried apples or bananas in little pouches at your local grocery, or the full meals you can get in the camping section of a sporting goods store.  The process used to preserve these foods is essentially the same as what we use to preserve our rose petals.

In technical terms, freeze drying is lyophilization, the process of water sublimating from the solid phase (ice) to the gas phase (vapor) without passing through the liquid phase (water).  In simpler terms, boiling ice!  So how does this make our petals so beautiful?  You already know how roses wilt and turn brown over time.  Well, we can literally “freeze” them in their perfect state.

We start by removing all of the petals from the roses and loading them into our freeze dryers, which freeze them to temperatures below -30 degrees.  We then remove nearly all of the air inside the chamber using vacuum pumps, which causes the ice in the petals to turn directly into vapor.  By continuously removing the vapor over the course of about two weeks, the petals end up completely dry, but in almost the same shape and color as they were when they were fresh.

Once the rose petals are removed from the freeze dryer, they can simply be stored at room temperature.  There is often a misconception that the petals need to be kept frozen, but the term “freeze” in freeze dried only refers to the preservation process.  They are best stored in a dark, dry location, such as a closet.  Light and humidity can fade the colors, while properly stored petals can last for months or even years.

You can use freeze dried rose petals the same way you would use fresh petals, but without worrying about wilting.  You can get them well ahead of time and prepare your decorations in advance.  To look at the petals, it’s hard to tell the difference between fresh and freeze dried.  Can you tell them apart in the photo below?

Fresh rose petals vs freeze dried, can you tell the difference?

Fresh rose petals vs freeze dried, can you tell the difference?  One group of petals above is over 2 months old, the other just came off a rose.

The most noticeable difference is that freeze dried are dry; an obvious, but commonly overlooked fact.  This makes them more delicate, however, they can be softened by re-introducing moisture.  In humid climates, just exposing the petals to the air will begin to soften them, while in dry climates, a little help from a steamy bathroom is needed.  Most of the time, you don’t need to worry about softening.  For aisles or table decoration, just spread them out and you’re all set.  If you’re using them for tossing, softening can make them easier to work with.

While there is a lot more that goes into creating freeze dried rose petals, you have the basics down.  Oh, and in the photo above, the freeze dried rose petals are on the left.  Did you guess it correctly?  Let us know in the comments below.