JPH0341149B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a food drying method that can efficiently obtain dried food that is uniformly dried without blisters in appearance and has a good flavor. At least the oil is attached to the surface of the food by spraying, dropping or flowing oil, or by immersing the food in oil,
The gist is to then dry the food using superheated steam. BACKGROUND ART Superheated steam drying has been known as a drying method that can provide dried foods with excellent drying efficiency, a high degree of swelling, and even drying. However, when the present inventors applied the same drying method to various foods, it was found that when the same drying method was used,
The degree of swelling is higher than that of other drying methods such as hot air drying.
Although dry foods with good structure can be obtained efficiently,
It has been found that depending on the type of food to be dried, uneven drying may occur, and many blisters may occur on the surface of the food, detracting from its appearance. In other words, α of steamed noodles or steamed snack ingredients, etc.
When this drying method is applied to processed starch-based foods, blisters are noticeable on the surface of the food, and when drying is applied to highly adhesive stick-like agglomerates such as raw noodle blocks, Since the same rod-shaped pieces adhered to each other in the initial stage of drying, and thereafter drying proceeded in this state, drying efficiency tended to decrease and uneven drying occurred. In view of the above-mentioned current situation, the present inventors have carried out intensive research to resolve the defects of superheated steam drying. As a result, the unfavorable phenomena described above are all due to the water vapor that occurs on the food surface during the initial stage of superheated steam drying. It was determined that the problem was caused by condensation. That is, in the case of pregelatinized starch-based foods, the starch gelatinized film formed on the surface of the food by the previous gelatinization treatment becomes even stronger due to the condensation, which causes blistering. In the case of noodle blocks, the condensation increases the adhesion of the stick-like pieces and softens the stick-like pieces, making them more likely to stick to each other. Based on these facts, the present inventors conducted further research and found that, prior to superheated steam drying,
Spraying, dropping or pouring oil onto the food to the extent that the oil adheres to at least the entire surface of the food, or immersing the food in oil, and then subjecting the food to superheated steam treatment. By doing,
It has been found that the above-mentioned problem can be completely solved by repelling water droplets generated by condensation of water vapor and drying the food without allowing it to adhere to the surface of the food. In addition, when using this method, the oil content is much lower than that of so-called fried foods obtained by the conventional deep-frying method, and as a result, an unprecedented type of food that is not greasy and has a hot flavor can be obtained. We also found that The method of the present invention was completed based on the above findings. The method of the present invention will be explained in detail below. First, as the food to be dried that can be applied to the present invention, all food materials that have been previously subjected to drying treatment with the intention of obtaining dried products can be applied, and among them, raw noodles, steamed noodles, etc. When a noodle material such as noodles or a starch-based food material such as corn or potato-based snack dough is subjected to the present invention, the effects of the present invention, such as prevention of blistering and uneven drying, can be particularly effectively exhibited. In the present invention, prior to superheated steam drying, oil is sprayed, dropped, or flowed onto the food to be dried, or the food is immersed in oil to the extent that the oil adheres to at least the entire surface of the food to be dried. As mentioned above, the oil spraying, oil dripping, oil flow treatment, or oil immersion treatment in the present invention must be performed until the oil is deposited over the entire surface of the food. The time required for either process is extremely short. Particularly when immersing the food in oil, it is sufficient to immerse the entire food in the oil, as the oil will adhere to the entire surface at that point. As a result, the amount of oil in the food can be significantly reduced compared to the conventional deep-frying method, resulting in dried products with a warm oily flavor without being greasy, and also reduces flavor loss due to oil deterioration during storage. is not a problem either. In addition, in the present invention, it is also possible to adjust the oil content in the food to a desired level by adjusting the oil spraying, oil dripping, oil flow time, or immersion time in oil, thereby improving the oil flavor. For snack ingredients, etc. that you want to bring out on the front, you can achieve the desired flavor by continuing oil spraying, oil dripping, oil flow treatment, or oil immersion treatment until a predetermined oil impregnation level is reached even after oil adhesion is complete. A dry product is obtained. It is also possible to flavor the oil used in the present invention in advance with a desired flavor, or to use a so-called seasoning oil. In addition to the above-mentioned flavoring effect, the oil adhesion treatment of the present invention is characterized by the presence of an oil film formed on the surface of the food product due to the oil adhesion. As a result, even if the food to be dried is a food material consisting mainly of pregelatinized starch, such as steamed noodles, blistering does not occur during superheated steam treatment, and even raw noodle lumps, etc. Even in the case of an agglomerate of highly adhesive rod-shaped pieces, the rod-shaped pieces do not adhere to each other, and uneven drying and reduction in drying efficiency do not occur. Furthermore, in the present invention, if heated oil is used at a temperature of about 50°C or higher, preferably about 50 to 90°C, and the temperature of the food to be dried increases as the oil adheres, the water vapor in the initial stage of the superheated steam treatment can be heated. It becomes possible to reduce the amount of dew condensation itself, and the effects of the present invention become even more remarkable. At this time, there is no problem even if the food to be dried is dried. In the present invention, the food after being coated with the oil is subjected to superheated steam treatment to dry the food. The superheated steam treatment conditions at this time are not particularly limited, and may be carried out under conditions depending on the type, size, shape, or desired food flavor or food structure of the food to be dried. For example, if you want a snack food with a high swelling degree, crispy and light texture, or dried noodles with good restorability, superheated steam at a relatively high temperature of 150 to 230 degrees Celsius is generally used. A rapid drying process is carried out in a short period of about 10 to 30 seconds using a Perform a slow drying process for about 50 to 180 seconds using low-temperature superheated steam. As described above, the effects of the present invention are fully exhibited under any of the conditions described above, and the drying efficiency is also extremely high compared to superheated steam treatment without oil adhesion treatment. The dried food thus obtained has no drying unevenness, is dried uniformly over the entire surface, and has virtually no blisters on its surface. The present invention will be explained in more detail with reference to Examples below, and the properties will be compared with a control product.
The effects of the present invention will be further clarified. Example 1 Wheat flour, salt, etc. are mixed with water and rolled in a conventional manner, and then simultaneously cut with a cutting blade roll and cut into one serving of raw noodle strings (moisture content 37.3%, product temperature
25°C), and after loosening it appropriately, it was packed in a rectangular form made of wire mesh so as not to be too dense. Next, oil at a temperature of 80° C. was evenly sprayed for 20 seconds (50 kg/hour) to adhere the oil to the entire surface of the raw noodles. The temperature of the raw noodles rose to 65°C by the same treatment. Subsequently, the same raw noodles were treated with superheated steam at a temperature of 170° C. and a flow rate of 8.5 m/sec for 96 seconds to obtain dried noodles (moisture content: 10.1%) according to the present invention. [Sample A] Control Example 1 Raw noodle strings were obtained by the same method as in Example 1, and after being packed into a frame, they were treated with superheated steam in the same manner as in Example 1 to obtain control dried noodles (moisture content 10.5%). )
I got it. [Sample B] Example 2 Raw noodle strings obtained by the same method as Example 1
Steaming was performed for 60 seconds using saturated steam at 100°C to obtain steamed noodle strings (moisture content: 39.8%), which were then loosened appropriately and packed into a rectangular mold so as not to be dense or dense. Next, the noodles were immersed in oil at a temperature of 60° C. for 2 seconds to coat the entire surface of the steamed noodles with oil. Subsequently, the same steamed noodles were treated with superheated steam at a temperature of 170° C. and a flow rate of 8.5 m/sec for 100 seconds to obtain dried noodles (moisture content: 10.1%) according to the present invention. [Sample C] Control Example 2 Steamed noodle strings were obtained by the same method as in Example 2, and after being stuffed into a frame, they were treated with superheated steam in the same manner as in Example 2 to obtain control dry noodles (moisture content 10.9%).
I got it. [Sample D] Control Example 3 Steamed noodle strings were obtained in the same manner as in Example 2, and after being stuffed into a frame, they were immersed in oil at a temperature of 160°C for 115 seconds to be deep-fried to obtain control dry noodles. (moisture content 10.6%) was obtained. [Sample E] The samples produced in each of the above examples were compared in terms of their dry state or flavor after restoration. The results are shown in Table-1.

【table】

[Table] As is clear from the above results, Sample A and Sample C according to the present invention were subjected to superheated steam drying under exactly the same heating conditions as compared to Control Samples B and D, respectively. Nevertheless, a large amount of water in the raw noodles evaporated, indicating that the method of the present invention is superior in drying efficiency. Furthermore, the product of the present invention has no large drying unevenness as in Comparative Products B and D, and is dried almost uniformly over the entire surface, and its appearance is also good, with no or almost no blisters. In addition, the product of the present invention had a significantly lower oil content and a pleasant, hot flavor compared to the control sample E obtained by the conventional deep-frying process. Example 3 After stirring and mixing wheat flour, pregelatinized starch, skimming, monoglyceride, and dried egg white, water is added and stirring and mixing are continued to obtain a dough. The dough is formed into a sheet using a rolling mill, and then punched into an appropriate shape to form a food material. Next, seasoning oil at 60°C was sprayed evenly for 10 seconds (30 kg/hour) to coat the entire surface of the material. The same material was then treated with superheated steam at a temperature of 240°C and a flow rate of 5 m/s for 170 seconds to reduce the moisture content to 4.3%.
An oil-flavored snack according to the present invention was obtained. Although the oil content of this snack is 7.2%, which is much lower than that of regular fried snacks, it has a refreshing and pleasant oil flavor, and its texture is also crispy, light, and delicious. It was hot.

[Claims]

1. After storing the food to be dried in a microwave-permeable and gas-permeable container, the food to be dried in the container is microwave-dried while rotating the container in a substantially vertical circle in a microwave dryer. A food drying method characterized by: