Freezing is often one of the quickest and most convenient methods to preserve food items at home for most of us. It is the most popular way of preserving leftovers, fruits and vegetables, but what we do not often assess is that freezing food items can take out a big chunk out of their total nutritional value.

Here’s how freezing food, such as fruits and vegetables, can affect its nutritional content:

Freezing food leads to chemical decomposition:

• Fresh fruits and vegetables, when frozen, undergo various chemical changes, which can cause spoilage and deterioration of the food products. For instance, fresh fruits contain important nutrients in the form of enzymes, which lose their nutrition value, color and flavor when stored in a freezer.
• According to a scientific paper submitted in the Journal of Nutritional Sciences, the major problem associated with freezing food is that it causes discoloration of food products and loses its vitamin C content, which is essential for our growth and development.
• Another harmful chemical change that takes place after freezing food products is the development of rancid flavors, due to oxidation with air. Researchers at Ohio State University have proved in a research study how freezing food items can lead to chemical decomposition and drastic loss of nutrients from food items. Cooked meat, steak, and pork containing high levels of salt when frozen tend to undergo oxidation and go rancid more quickly, leading to a shorter storage life.

Freezing food can lead to moisture and nutrient loss:

• According to the European Food Information Council, freezing food can lead to the growth of ice crystals, which can cause detrimental changes to the nutritional value of the food items. Formation of large ice crystals on food items can change its texture and flavor, resulting in greater loss of moisture from food.
• Dehydration of frozen food can drastically reduce the quality of food and cause nutrition loss, especially in fresh fruits and green leafy vegetables.

Freezing food can lead to harmful microbial growth:

• Contrary to popular belief, freezing food does not destroy the harmful microorganisms present on fruits and vegetables. There is still a sufficient population of microorganisms present in freezers, which further accumulates on the food items stored and multiplies in numbers consequently. This will lead to spoilage of food product and cause a drastic reduction in the nutritional content.
• A research paper submitted by William Schafer, a celebrated food technologist at University of Minnesota in 2014, suggests that storing food items in the freezer can lead to a loss of important nutrients, eventually resulting in destruction of food value.

Freezing food can lead to a drastic loss in nutrients and important vitamins. Hence, to save the nutritional content of your food items, you should avoid freezing them for longer periods of time and consume them as naturally as possible, to help retain their healthy nutritional value.

Reference:

http://www.extension.umn.edu/food/food-safety/preserving/freezing/the-science-of-freezing-foods (accessed on 12/2/2015)

http://missourifamilies.org/quick/foodsafetyqa/qafs327.htm (accessed on 12/2/2015)

http://ohioline.osu.edu/hyg-fact/5000/pdf/5401.pdf (accessed on 12/2/2015)

http://www.eufic.org/article/en/artid/freezing-foods-quality-safety (accessed on 12/2/2015)

http://www.csiro.au/Outcomes/Food-and-Agriculture/Storage-Life-Of-Foods/Frozen-foods.aspx (accessed on 12/2/2015)

Helpful Peer-Reviewed Medical Articles:

Hindmarsh, J. P., Russell, A. B., & Chen, X. D. (2004). Experimental and numerical analysis of the temperature transition of a freezing food solution droplet. Chemical engineering science, 59(12), 2503-2515.

Archer, D. L. (2004). Freezing: an underutilized food safety technology?. International journal of food microbiology, 90(2), 127-138.

Heldman, D. R. (2006). Food freezing. In Handbook of Food Engineering, Second Edition (pp. 427-470). CRC Press.

Leygonie, C., Britz, T. J., & Hoffman, L. C. (2012). Impact of freezing and thawing on the quality of meat: Review. Meat science, 91(2), 93-98.