If Your Bottle Of Nopal Cactus (Prickly Pear) Capsules Do Not Contain the Words "Freeze Dried" On The Label, You Are Wasting Your Money & Not Getting The Full Health Benefits
What Is Freeze Drying
Freeze drying refers to taking biological material naturally high in water, freezing it, and then extracting the ice from it. Freeze drying is the only process known to entirely preserve biological material without destroying the fruits’ or vegetables’ enzymes and nutrients(1*). If your bottle of nopal cactus (prickly pear) capsules does not say “freeze-dried,” then do not buy them, as you are not getting the full health benefits.
At Natural Home Cures, we place our nopal cactus (prickly pear) in a temperature and pressure-controlled environment. Specifically, the pressure is lowered to such a large degree that the ice in the nopal cactus (prickly pear) "sublimates" - turns from solid to gas, bypassing the liquid phase. The result is a stable substance with a long shelf life that is lightweight and maintains its nutritional content. To understand how freeze-drying works, we need to explore how the relationship between temperature and pressure affects the states of water(2*).
When we use the term- "states of water", we are referring to the solid, liquid, and gas states of water that we are all familiar with. For example, water in its solid state is ice, water in its liquid state is water, and water in its gaseous state is steam.
If you need help envisioning this concept, try the following thought experiment: Imagine holding a block of ice; now imagine placing that block of ice into a pot hanging above a fire. Gradually, the fire heats the ice until you’re left with a pot of water. What once was solid is now liquid; the scientific term for this is a “phase change.” The water has changed phases from solid to liquid. Imagine leaving the water in the pot with the fire still roaring underneath. Eventually, the water will start to boil and evaporate into steam. This is another phase change from liquid to gas.
In the example above, heat was the only thing we added to the ice to cause the phase changes. The pressure, or the force exerted on us by the gases in the atmosphere, remained the same. But pressure can have a profound effect on phase changes. Atmospheric pressure affects how long it takes for a substance to move through the various states of matter. As a rule, low temperatures and high pressures favor a solid state, while high temperatures and low pressures favor a gaseous state. This is why water boils faster at higher elevations than at lower elevations. The lower pressure conditions of high elevations shift the boiling point of water. But pressure can be manipulated to create a dramatic effect in phase change called sublimation. This is where water changes phases from a solid directly to a gas: If the pressure is sufficiently low, even in the absence of high heat, ice will sublimate(2*).
Below, we will break down the stages for freeze-drying: pretreatment, freezing, primary drying, and secondary drying.
Pretreatment
In this stage, the nopal cactus (prickly pear) is readied to be freeze-dried. We cut our nopal cactus (prickly pear) into smaller pieces and then ground it up, so it's easier to freeze dry and encapsulate(3*).
Freezing
The freezing stage is a crucial step in the preservation process. The entire point of freeze-drying is to preserve the nutrients, antioxidants, and other complex natural compounds found in our nopal cactus (prickly pear) supplements. To achieve this, the nopal cactus (prickly pear) must be frozen quickly. If the freezing process is too slow, large ice crystals will form, destroying the nutritional value of our nopal cactus (prickly pear) product.
To understand the reason large ice crystals destroy nutritive value, we need to delve into what makes our nopal cactus (prickly pear) supplement beneficial in the first place. The 3D structure of the molecules in our nopal cactus (prickly pear) gives it its health benefits. Remember that most organic material contains a large amount of water which will readily turn into ice crystals if exposed to temperatures below freezing. If large ice crystals are formed during the freezing process, they will destroy the 3D structure of the molecules they form(3*).
For a concrete example, think about what happens when you leave a can of soda in the freezer overnight. Because of the unique properties of water, the liquid in the can expands as it freezes. As the soda water freezes, the soda's total volume increases, which causes the frozen solution to burst out of the can. The can is no longer a large enough container for its contents. The result—is a permanent deformation of the soda can.
The soda can, for example, is a macroscopic version of the microscopic event which occurs within the molecules of a frozen supplement. If we think of the can as representing the 3D shape of a beneficial molecule and the soda as the water content of that molecule, it’s not hard to imagine that the same type of deformation that happened to the soda can will happen to a waterlogged molecule; the difference is simply a matter of scale.
How do we avoid large ice crystals? In short, we freeze our nopal cactus (prickly pear) quickly. To accomplish this task, the nopal cactus (prickly pear) is placed in a machine that rapidly cools it to -100 degrees Fahrenheit. After this, we move on to the primary drying stage.
Primary Drying
In this stage, the frozen nopal cactus (prickly pear) is transferred to a chamber where the pressure and temperature can be controlled. The pressure is lowered to around 0.8 torrs (a measure of pressure) at which point the ice begins to leave the material via sublimation. This process takes a few days as high amounts of heat cannot be used without damaging the nutrient content of the supplement. Most water is removed from the nopal cactus (prickly pear) during this stage(3*).
Secondary Drying
During secondary drying, the pressure is lowered even further, and the temperature is increased slightly to remove any liquid water in our nopal cactus (prickly pear). After the secondary drying process is complete, our Natural Home Cures Freeze Dried Nopal Powder Capsules (Prickly Pear) is ready to be consumed(3*).
Why bother taking the water out of our nopal cactus (prickly pear) in a time-intensive manner? In a word, preservation. Wet materials or materials with their water content intact spoil much more quickly than dry materials. Further, dry materials are lighter and thus less expensive to ship to you, our valued clients. Again, suppose we didn’t care about the nutritional content of our nopal cactus (prickly pear). In that case, we could use hot air or the sun to dry them like 99.9% of the other nutritional companies selling their nopal cactus (prickly pear) capsules.
We don’t use those two methods of dehydration because high heat destroys the 3D shape of molecules (albeit via a different mechanism than ice crystals do), which in turn destroys the health benefits, and what would be the point of that? Yet most consumers buy nopal cactus (prickly pear) capsules that are not freeze-dried, thinking they are getting the same nutritive quality when they are not(4*).
Freeze drying is a technical and finicky process, but the result is a stable, long-lasting, and higher-quality product that can only be found at Natural Home Cures.
Source References
(1) Food Navigator: Freeze Drying Fruit Is Top Technique For Retaining Nutrients
(2) Perdue University: Phases
(3) Wikipedia: Freeze Drying
(4) SP Scientific: Freeze Drying Lyophilization Basics