What exactly is freeze dried fruit?
In contrast to regular dried fruits (like sultanas, dates, dried mango etc) freeze-dried fruits are firstly frozen to -40 °C using a blast freeze vacuum chamber. Then with the surrounding pressure slowly lowering, the frozen components undergo a chemical change from solid to gas. It takes a whole week to complete and the final products are stored completely airtight to preserve them.
This process is a unique form of food preservation as it protects the cell structure and shape with no major loss in fruit volume. The low temperature also helps lessen nutrient losses, which are often seen in air or oven dried processing..
For the detail nerds, the freeze drying process occurs in 3 stages. The first involves quickly freezing, the second is slowly drying, where the ice components are sublimed (removed or changed) at sub-atmospheric pressure. The third stage is a secondary drying step where any remaining unbound water molecules are desorbed from the drier food parts.
How to use freeze dried fruit
Freeze dried fruit is like a concentrated version of the real thing. It’s crunchy and can satisfy that carby-potato-chip craving we sometimes (often) have. A bit like flavoured, crispy air. It’s virtually weightless and doesn’t have the same chewy texture you’d expect in most traditionally dried fruits. It’s completely different which is what makes it so great.
Crush it over ice cream or add it to granola. It travels really well, similar to traditional dried fruit. It’s perfect in a trail mix or in your backpack on long road trips.
It’s an especially clever invention for kids as there’s no sticky mess.
Freeze dried fruit also re-hydrates, almost back to a fresh state, making it ideal for smoothies, yoghurt or ice cream.
You can freeze dry almost any food. Here’s some typical freeze dried fruit examples:
- blood orange
Is freeze dried fruit healthy?
Due to the low freezing temperature, produced under vacuum pressure, freeze dried fruit retains most of the nutritional value, colour and shape of its original form. All of the fibre is preserved and around 95% of the nutrient content as well. This is particularly impressive as water-soluble vitamins like vitamin C, beta carotene and B vitamins are sensitive to most cooking methods.
The coolest part? Unopened, freeze dried fruit can live happily in the pantry for 25 years. Completely preservative free.
Health Benefits of Freeze Dried Fruit
There is some impressive research on freeze dried berries, including strawberries, blueberries and black raspberries. The benefits range from anticancer, reduced inflammation, improving brain function, supporting insulin function and improving osteoarthritis. Here’s a summary of why freeze dried fruit is such a wonderful and healthy snack.
Freeze Dried Black Raspberries Reduce Cancer Risk
Black raspberries boast antiangiogenic and antitumour properties in some existing research. One study from 2015 included a group of 28 patients with bowel cancer. They were administered 60g of freeze dried black raspberries over a course of 9 weeks. At the end of the study, the results showed that freeze dried black raspberries had a metabolic effect on tumour development and the energy pathways involved in cancer cells. The authors stated that black raspberry may be a beneficial therapeutic agent against colorectal cancer pathogenesis.
Freeze Dried Strawberries Improve Osteoarthritis Symptoms
A recent clinical trial revealed that strawberry supplementation can alleviate pain and reduce inflammatory markers in adults with knee osteoarthritis. In this crossover RCT, the effects of freeze dried strawberries on a gorup of obese patients with high levels of inflammation and pain were measured. The test group received 50g of freeze dried strawberry supplements per day for 12 weeks. The results showed that high-sensitivity tumour necrosis factor-alpha (hs-TNF-α) was significantly reduced in blood samples following strawberry supplementation. The patients also reported reductions in pain following strawberry consumption during the study period. This indicates that freeze dried strawberry is a valuable anti-inflammatory intervention in obese adults with knee osteoarthritis.
Freeze Dried Strawberries Improve Diabetes Markers
A study published in the Annals of Nutrition & Metabolism journal assessed strawberry extract on insulin sensitivity and glucose responses. 50g of freeze dried strawberry (FDS) was the subject of a recent randomised trial in a small group of diabetic women. FDS successfully reduced C-reactive protein, which is a blood marker for systemic inflammation. It also saw a reduction in glycosylated haemoglobin, which is a diagnostic marker for diabetes. Overall, FDS improved blood glucose responses and improved inflammation in diabetic participants.
Freeze Dried Wild Blueberry Enhances Brain Function in Children
A double blind study with children aged between 7-10 observed the benefits of drinks containing 15g or 30 g of freeze dried wild blueberry powder. Overall, cognitive performance improved with 30g of wild blueberry extract and was a dose-response result. Memory, word recognition and word processing tests were all undertaken in this group of children, confirming the positive effects of freeze dried blueberries on brain function.
Freeze Dried Blueberries Reduce Systemic Inflammation
Blueberry consumption has been widely reported to help reduce oxidative stress and inflammation. These systemic issues are key drivers for chronic disease including cardiovascular disease, alzheimers and cognitive decline. A study involving 40 postmenopausal women with mild hypertension measured the effects of 22g of freeze dried blueberry powder per day. Blood biomarkers of DNA damage antioxidant defense systems were assessed in the participants. An initial improvement in antioxidant levels was observed at the halfway point of the study, which suggests freeze dried blueberry has an acute anti-inflammatory and antioxidative effect in hypertensive postmenopasual women.
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