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Features of drying

Features and benefits of drying

The heat treatment "drying" may be a method not done much in common households.
However, looking into the kitchen, there are lots of dried foods, so-called dry matter, which greatly affects the diet of people.
Dry matter is a kind of heat-treated food that removes moisture from foodstuffs, improves preservability and adds umami.
If you say "dry" which is carried out at home in general, there is a method called "heavenly sunshine" and there may be people who are making dry shiitake etc by oneself and dry the sliced vegetables and fruits, and there may be people making vegetable chips and fruit chips.

Although it may be less when you make dry matter from raw ingredients yourself, a lot of people use dried foods that are being sold.
Because there is a merit that condensation of sweetness and umami are increased as well as preservability improves by decreasing moisture.
In addition, purchasing dry matter means that there are companies and stores that provide the dry matter, but considering distribution, it will lead to restraining the distribution cost besides improving preservability and taste. There is also merit.

1. Improve storage
Water is necessary for living things to live, and vegetables, fruits and meats, which are the foods everyday, contain a large amount of water.
Moisture is an important factor not only for higher organisms but also for microorganisms such as bacteria and fungi called spoilage bacteria.
Foods without moisture can not easily grow even though microorganisms are abundant even though nutrients exist abundantly.

Dried food ingredients called dry matter have the merit of improving preservation by suppressing the growth of microorganisms by removing moisture from fresh ingredients.
Fresh ingredients are kept in the refrigerator and kept safe, but even if they are kept at low temperature it can be safely eaten deliciously only for a few days.
However, dried foodstuffs can be stored on a monthly basis even if they are stored at room temperature and can be used just by dipping in water or hot water before use.

 

2. Improve taste
As an example of the merit of "drying" of improving taste, dried shiitake mushrooms, dried radish, dried potatoes, etc. are Japanese foodstuffs, but there are Chinese foodstuffs which improves umami by drying such as dried abalone and dried sea cucumber .
As you can imagine the images of these foods, it can be said to dry by gentle warming typified by sun drying. Considering the sun drying, dries that increase the umami as well as increasing the preservability of the fish will be a dry matter with a lot of residual moisture.
There are also mirin dried seasoned seasoned to fish dried fish as soon as it is baked and there are things like dried rice which has been dried in a half - life state so that the texture of raw is not greatly destroyed.
These dried foods will increase umami with the effect that enzymes are activated and decomposition of proteins and carbohydrates is promoted by adding moderate temperature.
Of course, moisture is necessary for the enzyme to function, but in the case of mild conditions like sun drying, there is enough time for umami and sweetness to increase even if it is a reaction to dry.

 

3. Method of drying food
Some dry matter becomes another texture and taste by drying, there are also dry matter which can return to original state when returned with water or hot water.
In addition, there are cases where drying improves not only preservability but also umami like dried fish and dried shiitake mushroom.
Therefore, the drying method will change depending on the purpose of how you want dried food.
Dried food ingredients called dry matter have the merit of improving preservation by suppressing the growth of microorganisms by removing moisture from fresh ingredients.
Fresh ingredients are kept in the refrigerator and kept safe, but even if they are kept at low temperature it can be safely eaten deliciously only for a few days.
However, dried foodstuffs can be stored on a monthly basis even if they are stored at room temperature and can be used just by dipping in water or hot water before use.

 

1-1 Natural drying
A method called dry sun drying or shade which has come out several times so far is natural drying.
It takes time and effort, plus a place to spread it, but it is a low cost way to dry it.
Also, since the temperature condition is mild, it is also possible to increase the umami and sweetness by the action of enzymes in the food during drying.
It is a method used when building dried fish, dried shiitake mushrooms, dried gourd and the like.
It can be said that experience and know-how are necessary for making products of stable quality, as it can be seen from the necessity of a large place as it is not suitable for mass production, it is likely to be affected by the weather.

 

1-2 Artificial drying
In order to mass-produce industrially, it is necessary to artificially remove moisture rather than relying on the weather.
The most common one is a drying method to prepare a strong heat source, but for drying of nutrients contained in foods and foods susceptible to denaturation by heat, low temperature drying close to sun drying, vacuum freeze drying, or addition There are cases where pressure drying etc is applied.

 

1-2-1 Hot air drying and low temperature drying
It is a method of sending out the heat generated by the heat source by wind, that is, blowing hot air to blow the food.
Although it is merit that the drying time can be shortened with a simple device, there is a disadvantage that the degree of drying is different between the center and the inside of the food, the outside shrinks and hardens.
When it is desired to suppress the influence of heat on ingredients, it takes time, but low temperature drying may be adopted.
Because it blows dry air of 20 ℃ ~ 30 ℃, there are cases where destruction of nutrients is little and it is used for drying vegetables and fruits.
Even when using fats as dried fish, low temperature drying may be used to avoid oxidation.

 

1-2-2 Spray drying
It is dried in powder form by a drying method which instantly removes moisture by blowing liquid food into droplets and blowing it into a can together with hot air.
It is a drying method used when making coffee powder or skim milk.
Although degradation of food due to heat is small, it is disadvantageous that a large volume is required for the amount of powder that can be made, and the apparatus becomes large.

 

1-2-3 Fluid bed drying
It is a drying method that makes powdery food float in the air current together with a binder to make it into a granular form.
It is a convenient way to make all-in-one soup and coffee powder because you can make granules that uniformly contain many kinds of powder.
It becomes porous granule so it is easy to supply water, it melts quickly in hot water, so it is suitable for processing soup and coffee.

 

1-2-4 Drum drying
It is a drying method of applying paste-like food on a metal drum heated to high temperature, drying it while rotating the drum, and scraping and collecting the dried one.
Although it is necessary to crush and sieve after drying, powder can be made at low cost compared to spray drying.
Incidentally, since heat is applied longer than spray drying, the component change due to heat becomes stronger than spray drying.

 

1-2-5 Vacuum lyophilization
It is a drying method which converts ice into steam and evaporates it under high vacuum condition after freezing the food.
It is possible to leave nutrients of food almost completely, and it has excellent resilience when feeding water.
Although it is a method suitable for drying ingredients such as instant foods, it is disadvantageous that the drying cost is high and the finished product itself becomes porous and becomes brittle.

 

1-2-6 Pressurized drying
It is a drying method which instantly evaporates moisture by rapidly returning to normal pressure from a state of high temperature pressurized in a sealed container.
It is a drying method used for manufacturing such as millet puffs called swelling foods.
For familiar things, there is "Pon candy" which pressurized and dried the rice.
Besides, it is sometimes used to give chewy texture of cereal food or chocolate.

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