JPS59125838A - Method for preventing freeze denaturation of rootcrop and fruit vegetable - Google Patents

Abstract

PURPOSE:To prevent the degradation of the taste of rootcrops and fruit vegetables after thawing, by immersing the rootcrops or fruit vegetables in an aqueous solution of an organic acid salt before freezing. CONSTITUTION:The rootcrops such as carrot, Japanese radish, etc. or fruit vegetables such as eggplant, pumpkin, etc. are immersed in an aqueous solution of an organic acid salt such as sodium glutamate, potassium citrate, etc. having a concentration of 0.05-5%, preferably 0.1-2%, at 5-70 deg.C for about 5-60min, and the vegetables are washed with water and frozen.

Description

[Detailed description of the invention] The present invention relates to a method for preventing denaturation of vegetables during freezing.

Among fresh foods, vegetables tend to lose their freshness during storage, and when they are frozen, for example, in order to preserve their shelf life, they do not easily reconstitute after thawing.

That is, for example, when root vegetables such as carrots and radishes are frozen and then thawed, they become excessively vermilion and have a spongy texture, which is less than the original texture of the root vegetables. (Thus, the present inventors conducted research and found that if these vegetables were immersed in an aqueous organic acid salt solution and then frozen, the texture of the vegetables after thawing did not change in quality.

The present invention is a method for preventing freeze denaturation by immersing root vegetables such as carrots, burdock, radish, taro, and potatoes, and fruit vegetables such as eggplants and pumpkins in an aqueous solution of an organic acid salt.

Examples of "organic acids" include sodium salts or potassium salts of acids such as citric acid, lactic acid, succinic acid, malic acid, aspartic acid, glutamic acid, tartaric acid, gluconic acid, acetic acid, fumaric acid, and phosphoric acid. Among these, especially glutamic acid,
Salts of υcarphonic acids such as citric acid are preferred. The concentration of the immersion liquid is preferably 0.05 to 5%, particularly 0.1 to 2%. If the concentration is lower than the above range, the present invention will not be effective and the salt will taste high and the salt used will appear.

The temperature of the soaking liquid is preferably 5 to 70°C; if the temperature is too low, it will take a long soaking time to obtain the effect, and if the temperature is too high, the vegetables will denature and the salt will not be effective.

The appropriate immersion time is 5 to 60 minutes under the above conditions.

Next, the root vegetables are washed with water and then frozen. Some types of root vegetables require cooking before eating.
In that case, after performing the above-mentioned treatment, it may be heated and then frozen. When the capped root vegetables of the present invention are to be applied to retort foods, they are retorted together with other raw materials as needed after freezing. At this time, by immersing the root vegetables that have been subjected to the above-mentioned freeze resistance treatment in an aqueous calcium salt solution, it is possible to prevent spotting during retort treatment.

As mentioned above, according to the method of the present invention, the texture of root vegetables does not change even when frozen, so it is possible to perform treatments that impart preservation properties such as freezing and retort processing, which has a wide range of applications. It is.

Another advantage is that the target vegetables can be supplied in a variety of conditions according to individual needs, from raw vegetables to boiled vegetables that can be eaten immediately after thawing.

Example 1 Sliced carrots are immersed in an equal amount of sodium dithiglutamate aqueous solution at 70° C. for 15 minutes, and then washed with water. The obtained carrots were frozen at -60°C.

Example 2 Potatoes measuring 10 square meters were immersed in an equal amount of 0.25% potassium citrate aqueous solution at 50° C. for 30 minutes, and then washed with water. Next, the obtained potatoes are immersed in an equal amount of 0,3-thi anhydrous calcium chloride aqueous solution at 90° C. for 60 minutes, and then washed with water.

The potatoes subjected to the above treatment were frozen at -60°C.

Example 6 A 10" square radish was immersed in an equal amount of 0.1% disodium conolate aqueous solution at 20° C. for 60 minutes.

Next, 0.3 parts of calcium chloride per 100 parts of the solution is added to this solution, heated to 90° C., and left for 30 minutes. The obtained radish was washed with water and then frozen at -20°C.

Example 4 101 cubes of pumpkin were soaked in an equal amount of 4.5% phosphoric acid) I
After soaking in a Jumium aqueous solution at 5° C. for 60 minutes, it is washed with water.

The obtained pumpkin was frozen at -20°C.

Application Example The frozen potatoes obtained in Example 2 are thawed and added to a cream soup. This soup was placed in a retort pouch, sealed, and sterilized by pressure and heat at 121° C. for 60 minutes. The texture of the potatoes in the resulting soup was the same as that of potatoes that had been conventionally boiled.

Patent applicant: Nisshin Seifun Co., Ltd.

Claims (1)

[Claims] A method for preventing freeze denaturation of root vegetables and fruit vegetables, which comprises soaking the root vegetables or fruit vegetables in an organic salt aqueous solution and then freezing them.