What happens to food when its canned, dried, extruded and frozen?

The world we live in now requires fast motions, everything has to be done in fast manner, even food has to be prepared quickly. Many people rely on processed and packaged foods for speed and convenience but they lose control over what their food contains. The question is what is the cost (disadvantage vs advantage) of processed food? Processing food cuts preparation time but makes food life time longer and makes food safer for human consumption. On the other hand, processing food involves tradeoffs, such as losing some of the vitamins and mineral.

Let’s take pasteurization as an example; the ultra-high temperature (UHT) process is used for pasteurization, which makes the milk safe to drink therefore, it can be kept in a room temperature and has a longer shelf life (duration before expiration). The milk is sterilized by exposing it to temperatures above those of pasteurization just long enough. Irradiation is a similar method to pasteurization. The trade off in terms of nutrients lost vs gaining a safer food supply is probably trivial. At the same time processing food could be beneficial like removing milk fat or other food. 

The aim of processing food is to extend the usable life of food and preserve it for a longer time; therefore, processing must prevent three types of event. 1) enzymatic destruction of food molecules 2) oxidative changes 3) microbial growth. In the next section we will discuss different forms of food processing and their advantages and disadvantages.

Canned:  the canning process is one of the most effective ways of protecting the food from microbial growth. The canning process depends on two factors; temperature and time. Each level of temperature has different major effects on killing microbes, but only a minor effect on nutrients. On the other hand, long heating time is going to cause a severe lost in nutrients, as a result by administrating high temperature for a short time this effect can be lessened. The Canning does not affect fat soluble vitamins and most minerals.

Particular attention should be drawn to vulnerable water-soluble vitamins, vitamin C, and riboflavin. Some can be lost in canning but many more are diffused in food such as lime liquid, beans, corn, and meat. Fireman is stabilized by acid but the rapid Heat destroys. Riboflavin is resistant to heat but sensitive to sunlight as a result most likely to be lost from glass packaged but not canned. The HTST helps preserve vitamin C. Minerals are unaffected by heat, both water soluble vitamins and minerals leach into canning or cooking water which most people throw away. Therefore, my advice to you is to use the water because it contains minerals and vitamins. 

Freezing: freezing preserves food by rapidly slowing enzymes reactions and stops bacterial reproduction. Nutrient loss is minimal and nutrients content are similar to fresh food. The steps before freezing can destroy nutrients (washing, trimming or gridding).  Uncut fruits preserve its vitamin C but it can be lost when exposed to air or tissues are broken. Uncut fruits preserve most of its vitamin C and minerals. An advantage of freezing over fresh food is; frozen food develops its nutrients to their fullest potentials, always remember to keep frozen food at-17 degrees and don’t refreeze the food as it may lose nutrients. If the food has crystals after slight defrost then it is probably safe to eat but may lose texture and nutrients.

#MacroMondays – #b-food

Drying: is a method of preserving food by removing sufficient water from the food to eradicate microbial growth. Commercially dried food retains most of their nutrients but food dried in heated oven often sustain dramatic nutrient losses. While vacuum freeze drying conserve their nutrients. In addition, adding sulfur dioxide help preserves vitamin C but destroys Thiamin.

mix of organic dried fruit

Extrusion: isa method by which the form of a food is changed, for example, changing corn to corn chips. Foods like breakfast Puffs, potatoes ships, bacon bits all undergo processing such as heat to change shape and texture, nutrients are lost but most nutrients are added to compensate the loss. Most food that go under extrusion are deficient in vitamin E and fiber. People should not rely on them as staple food. Just enjoy them from time to time

Baked Dehydrated Apples Chips in a Bowl

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