Yes, you can freeze rhubarb without cooking it first, and this method is the simplest and quickest way to preserve the vegetable’s tart flavor for year-round use. Freezing raw rhubarb is highly effective because the stalks are primarily used in cooked applications like pies, crumbles, and sauces, where the texture change caused by freezing is not a concern. This preservation technique allows you to easily store the spring harvest and have pre-portioned rhubarb ready to incorporate into your favorite recipes at any time.
Preparing Raw Rhubarb for Freezing
The preparation process begins with carefully trimming the rhubarb stalks to ensure safety and quality. You must remove the leaves entirely, as they contain high levels of oxalic acid, which is toxic if consumed in large amounts. After removing the leaves, trim off the tough, woody ends of the stalks and any stringy bits that may be present.
Next, wash the stalks thoroughly under cold running water to remove any dirt or debris that may be clinging to the surface. Once cleaned, the stalks must be dried completely using a clean kitchen towel or paper towels. Removing all surface moisture is an important step, as excess water can lead to the formation of large ice crystals, which contribute to freezer burn and a decline in quality.
The final step in preparation is chopping the stalks into uniform pieces, typically about one inch in length. Cutting the rhubarb into consistent sizes ensures that all pieces freeze evenly and cook at the same rate when incorporated into a recipe.
Step-by-Step Freezing Techniques
The most effective method for freezing raw rhubarb is called flash freezing, which prevents the pieces from clumping together into a solid block. To do this, spread the chopped, dried rhubarb in a single layer on a rimmed baking sheet lined with parchment paper. The pieces should not be touching, which allows the cold air to circulate around each one individually.
Place the tray in the freezer for one to two hours, or until the pieces are frozen solid. Once the rhubarb is frozen, it can be quickly transferred from the tray into a long-term storage container. This flash-freezing step ensures that you can easily measure out a specific quantity of rhubarb later without having to thaw the entire batch.
For long-term storage, use airtight freezer bags or rigid freezer-safe containers. It is important to remove as much air as possible before sealing, as air causes freezer burn. For freezer bags, you can press the air out or use a straw to suck out the remaining air. Finally, label the container with the date and the quantity of rhubarb inside.
Thawing and Using Frozen Rhubarb
Freezing raw rhubarb causes the water inside the plant’s cells to expand, which ruptures the cell walls. This cellular damage means that once the rhubarb thaws, it will have a softer texture compared to its fresh state. The thawed rhubarb will also release a significant amount of liquid, a natural consequence of the broken cell structure.
For most cooked applications, such as pies, crumbles, and sauces, use the rhubarb directly from the freezer without thawing. Using it frozen prevents the recipe from becoming too watery during the initial cooking process. If a recipe requires a precise measurement or a less watery result, you can thaw the rhubarb in a colander set over a bowl to drain the excess liquid before use.
The softer texture of frozen rhubarb is suitable for recipes where the pieces will be cooked down, such as jams, compotes, muffins, and quick breads. Raw frozen rhubarb maintains its best quality for approximately six to twelve months when stored consistently at 0°F. Beyond this period, the quality, color, and texture will begin to deteriorate.