The concept of food preservation has been around since time immemorial. Before modern appliances like freezers and refrigerators were invented, people preserved their foods through natural means, such as drying or pickling.
Pickling involves immersing fresh foods like fruits and vegetables in vinegar or in a salt water solution that promotes the growth of fermentative bacteria. Drying, or food dehydration, on the other hand, involves the removal of moisture from foods by actively drying them in the hot sun. Because these techniques inhibit the growth of bacteria, mold and yeast that cause food spoilage, they effectively extend the shelf life of foods. [1]
In places that don’t have enough sunlight for drying foods, people use a different method of food preservation. The earliest form of freezing involved immersing fresh produce in ice and a salt brine. Considered one of the easiest and least time-consuming method of preserving food, freezing slows the growth of microorganisms as well as the activity of enzymes that cause fresh fruits and vegetables to ripen and mature. [2]
Compared to other methods like refrigeration, freezing is much better at preserving the nutrient content of fresh foods. However, freezing runs the risk of ice crystals damaging the cells of soft fruits, which can lead to them turning into mush. When thawed, vitamins and minerals inevitably leak out of these frozen goods. [3]
Drying, on the other hand, concentrates the nutrients in foods, potentially increasing the levels of certain vitamins and minerals. However, dehydrating foods can also concentrate their sugar and calorie content. And when done incorrectly, dehydration can actually lower the nutritional value of dried goods. [4]
Fortunately, a modern method of preserving foods was developed that combines the advantages of drying and freezing while addressing their disadvantages: freeze drying. Also known as lyophilization, this convenient technique requires no more than simple food preparation and the use of a freeze dryer. Freeze-drying not only allows foods to retain their original flavor and nutrient content, but it also makes them last longer than foods preserved using other methods. [5]
Freeze-drying and how it works
Freeze-drying is an intelligent technology that effectively removes water from perishable goods by freezing them instead of drying them using high temperatures. Freeze-drying involves three main stages: the freezing phase, the primary drying phase and the secondary drying phase.
The first phase
Freeze-drying is best accomplished using large ice crystals. That said, crystals that are too large can damage cell walls. To prevent the formation of these very large crystals, the freezing process is done rapidly. The temperature is then raised immediately to allow the crystals to grow. Freeze dryers usually have a built-in function that determines the amount of drying time required for the type of food you want to process. [6]
The second phase
The second phase, also known as the sublimation phase, involves lowering the pressure and heating the food to cause the ice to turn into water vapor. With the help of the vacuum that speeds up sublimation, this step removes about 95 percent of the food’s water content. Primary drying is done slowly since too much heat can change the structure of the food being processed.
The third phase
For the final phase of the freeze-drying process, the temperature is raised once more, only this time, it exceeds the temperature used in the primary drying phase. This ensures that water molecules still bound to the food are completely removed. The final phase also allows the freeze-dried food to retain its porous structure.
Afterward, an inert gas is used to break the vacuum so that the freeze-dried food can be sealed. The final product usually contains no more than five percent residual moisture.
The advantages of freeze-drying foods
Today, freeze-drying is considered one of the fastest growing trends in the food industry. This is due to the many advantages it has over other food preservation techniques. The upsides of freeze-drying include:
- Longer shelf life
Unlike dried, canned or frozen foods, freeze-dried foods can last up to 25 years if not opened and stored properly. The effective removal of their water content reduces the possibility of spoilage bacteria growing while the freeze-dried food is in storage. When storing freeze-dried foods, follow the instructions written on the package.
- Easy and convenient to use
Freeze-dried fruits, in particular, can be eaten on their own as a snack. They can also be used to make easy but healthy meals for people on-the-go. As an added bonus, you can enhance the flavor of your morning shake or smoothie anytime with your favorite fruit even if it’s not in season. Just toss a freeze-dried fruit of your choosing into your beverage and you’re good to go!
- Whole food nutrition
Freeze-drying allows you to extend the shelf life of foods without compromising their nutritional value. By combining the advantages of both freezing and drying with modern technology, freeze-drying can ensure that preserved foods retain at least 97% of their original nutrient content.
- High-quality food without any preservatives
Freeze-drying doesn’t require the use of any additives or preservatives. It also doesn’t alter the taste of foods. You can be sure that when you eat freeze-dried foods, you’ll get not only most of their nutritional benefits, but also the clean, unadulterated taste of fresh foods.
- Portability and easy storage
Freeze-dried foods come in oxygen-proof packaging that seals out moisture. They are lightweight, easy to store anywhere and require no refrigeration. These qualities make freeze-dried foods perfect for backpackers and preppers who have the foresight to stock food in case of disaster or emergencies.
Where to get high-quality organic freeze-dried superfoods
Due to the incredibly fast-paced world we live in today, people are living increasingly hectic lifestyles that leave them no time for healthy meal preps. Hence, the demand for ready-to-eat meals and preserved foods has risen quite astonishingly in recent years. But with this increase comes an alarming decline in people’s health and nutrition.
Freeze-dried foods offer the perfect solution to this dilemma. Not only are freeze-dried foods more reliable than convenience foods sold in stores, but they are also considerably more healthful and nutritious. The Health Ranger Store offers a variety of clean, organic freeze-dried superfoods that are perfect for people with busy lifestyles, as well as backpackers and preppers in search of foods that can provide quality nutrition.
Health Ranger Select Organic Freeze-Dried Superfoods not only offer plenty of health benefits, but they are also easy to incorporate into your daily routine. Some of our freeze-dried superfoods can be eaten on their own as snacks, while others can be sprinkled on cereals, added to your drinking water or mixed into your favorite shakes and smoothies.
Health Ranger Select Organic Freeze-Dried Superfoods are packed with essential vitamins and minerals, potent antioxidants and beneficial phytonutrients. Carefully preserved by freeze-drying, they can last long term in storage (especially the #10 can varieties) without the help of additives, synthetic chemicals or preservatives. Our products are non-GMO and certified organic and Kosher. They are also lab tested for glyphosate, heavy metals and microbiology.
Know any useful tips on how to make the best of freeze-dried foods? Share them in the comments below.
References
[1] https://www.italian-feelings.com/introduction-to-drying-food-the-oldest-method-of-preserving-food/
[2] https://ohioline.osu.edu/factsheet/hyg-5341
[3] https://www.sbs.com.au/food/article/2017/09/21/whats-better-you-fresh-dried-or-frozen-fruit
[4] https://www.alreadycooking.com/advantages-disadvantages-dehydrating/
[6] https://www.millrocktech.com/lyosight/lyobrary/what-is-freeze-drying/
