What is potato sulfitation and why is it needed?

Sulfitation is a technological processing of purified potatoes with a special chemical solution. It is carried out to prevent darkening of tubers, eliminate harmful microorganisms, and increase the shelf life of the product. This semi-finished product is transported over long distances and used in cooking.

Potato sulfitation: simple about the complex

Peeled and cut potatoes cannot be stored for long periods of time, as upon contact with oxygen they darken and become unsuitable for consumption. This happens due to an oxidation reaction: hydrogen leaves the tubers, oxygen is absorbed into the pulp. Although only the surface darkens, the quality of the vegetables seriously changes: their nutritional value decreases and their taste is lost.

To preserve their natural color, benefits and quality, the tubers are treated with a solution of sulfurous acid. The scientific name of the procedure is sulfitation.

What is it for?

Typically, peeled tubers are stored in water to prevent darkening, but this method has disadvantages:

• significant loss of nutrient solids;
• limpness;
• impossibility of long-term storage.

An alternative to this is sulfitation. Sulfurous acid not only protects potatoes from darkening, but also has antiseptic properties - it kills putrefactive bacteria and fungi. The protective film formed on the surface helps preserve the taste and beneficial properties of the vegetable.

Attention! After processing, potatoes are stored without darkening in color for up to 2 days. This allows you to transport it to any distance.

Essence and characteristics of sulfitation

How and why are potatoes sulfated? Peeled tubers are treated with an aqueous solution of sodium salts of sulfurous acid. As a result of their decomposition, sulfur dioxide (SO2) is formed. It inhibits the activity of the enzyme polyphenol oxidase, which delays the formation of melanins - pigments that cause darkening of vegetables.

Sulfur dioxide is hazardous to health. Its permissible content in vegetables is no more than 0.02%. Immediately after sulfitation, this figure exceeds the norm by 10–15 times. Therefore, before vacuuming, the potatoes are washed several times in clean water. Before use, desulfitation is carried out - removal of a chemical compound by heating. As a result, SO2 evaporates with water vapor.

By the way! Many people are interested in what it is - raw, peeled, sulfated potatoes. This is a semi-finished product for further industrial processing and use for culinary purposes.

How does sulfitation occur?

Processing is carried out at large enterprises during procurement work. The crop is sulfated immediately after harvest.

Preparation

This is the first important stage. Not all tubers are suitable for further processing. Characteristics of suitable vegetables:

• round or oval-round shape;
• the surface is smooth, without growths;
• the peel is thin;
• A small number of eyes is allowed, their maximum diameter is 5 mm.

Do not use defective potatoes with signs of disease or pest damage, frozen, limp, sprouted, small, mechanically damaged or rotten tubers.

Preliminary preparation begins with washing the potatoes. The tubers are thoroughly cleaned of dirt, and the peel is cut off in a thin layer. During inspection and cleaning, the remaining skins and eyes are removed, the vegetables are washed and kept in clean water until they are lowered into the working solution.

Reference. Whole and chopped tubers are sulfated. Various cutting forms are allowed: strips, slices, cubes, circles.

What solutions are used

Use sodium bisulfite or hydrosulfite. Chemical formula: NaHSO3. Available in pure form. Sometimes sodium pyrosulfite (Na2S2O5) is used, a white crystalline powder similar to baking soda that turns into bisulfite when decomposed in water.

To prepare the working solution, take containers from any non-corrosive material. The best option is stainless steel or food-grade plastic. Galvanized steel is not suitable. For every 10 liters of water take 4 g of bisulfite or pyrosulfite. The finished concentrate is reused up to 10–12 times.

Step by step description

Sulfitation is carried out using professional equipment in the workshops of the enterprise. Processing consists of several stages:

1. Peeled potatoes are kept in baths or barrels of water to prevent browning.
2. Tubers are selected from the container into duralumin meshes.
3. After the water has completely drained, the vegetables are treated with sodium bisulfite solution for 5 minutes.
4. The mesh is removed and the liquid is allowed to drain.
5. The tubers are washed in cold water. The potato:water ratio is 1:2. Carry out 2-3 full dives.

Ready-made sulfated vegetables are placed in containers, baskets or plastic bags. Potatoes are vacuum packed, labeled, stored or shipped for sale.

Read also:

How to get rid of mice and rats that gnaw potatoes in the cellar.

How to choose potatoes depending on the cooking method.

How to grow a bucket of potatoes from one bush.

Advantages and disadvantages

Processing has strengths and weaknesses. Advantages for manufacturers:

• the fastest possible processing of raw materials with low labor costs;
• possibility of transportation over long distances;
• preservation of presentation;
• increased shelf life.

The benefit for consumers is convenience and significant time savings. However, the quality of such potatoes is low; in terms of properties and benefits, they are inferior to fresh ones. Sulfated tubers are used to make chips and other similar dishes. Dried vegetables are completely free of sulfur dioxide.

Important! The disadvantage of the procedure is the toxicity of the working solution. Although the potatoes are soaked and washed and then cooked, a low concentration of bisulfite remains in the tubers.

Are these potatoes harmful?

According to sanitary standards, sulfated potatoes cannot be used in the production of infant formula, diet food, and canned food. Tubers treated with anhydride are prohibited in childhood.

Infrequent consumption of such vegetables does not harm the body. If you use the semi-finished product regularly and in large quantities, problems may arise. allergic reactions, digestive problems, vitamin B1 is washed out. Bisulfite accumulates in the body as a carcinogen.

Conclusion

Sulfitation is a method of technological processing of vegetables for industrial purposes at large procurement enterprises. It preserves the presentation of peeled potatoes and prevents oxidation and darkening processes.

The treatment is carried out with a working solution of sodium bisulfite (a derivative of sulfurous acid). The substance has an antiseptic effect on tubers, inhibits the viability of microorganisms, increasing the shelf life of the product. Peeled tubers are stored outdoors for 6–8 hours to 2 days.