JP2006166757A - Method for producing dried small sardine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing sanitary dried small sardine having good shape/form and a small number of general viable bacteria. <P>SOLUTION: The method for producing dried small sardine comprises raising drying temperature during drying time in a production process of the dried small sardine to a high temperature of ≥50°C so as to inhibit proliferation of heat-resistant spore bacteria to obtain a dried small sardine product having ≤300 pieces/g of the general viable bacteria. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a method for producing dried sardines such as anchovy, sardine, and urine eagle.

  Niboshi is a commonly used soup stock along with bonito and kelp when drawing Japanese dashi stock. In recent years, there are many anchovy fish species that are used as a raw material for boiled dried fish, but boiled dried fish such as sardines, uruma eagle, horse mackerel, flying fish, and salmon are also produced.

  In the conventional manufacturing process of boiled dried fish, the fresh fish raw material is washed with water, then boiled in hot water at 90-99 ° C for 5-10 minutes, and then placed in the water and dried with sun-dried 10-18% moisture. Until dry. However, sun-dried is easily affected by the weather, and the dry days are longer than one week, which makes it impossible to produce efficiently and is not good from the viewpoint of production in a hygienic environment. Therefore, in recent years, a drying method using a hot air dryer, which does not require drying time and has little drying unevenness, has become widespread. Hot air drying can be dried in about 1 to 2 days by sending hot air of about 30 to 40 ° C. into a drying cabinet with a powerful blower fan. The heat source of the dryer includes gas, electricity, steam and the like, and there are a direct fire method using the heat source directly as hot air and an indirect method using a heat exchanger.

  Niboshi is produced throughout the year, but the season of catching by fish species is limited to some extent. Looking at the anchovy that produces the highest amount of dried fish, Nagasaki Prefecture, the main production area, was often caught from December to May until several years ago. The fishing season has shifted in July.

  The price of Niboshi is decided by auction, but at this time, the quality of the quality of Niboshi is judged only by its appearance. In other words, the basis of evaluation is whether the fish is not broken, bent, peeled, discolored or yellowed.

  In the mechanical drying at high temperature, the fish body is cracked, bent, or peeled, so that it is generally dried at a low temperature of about 10 ° C. plus the outside air temperature. (For example, refer nonpatent literature 1.)

The outside air temperature plus 10 ° C. is around 20 ° C. in winter, around 30 ° C. in spring and autumn, and around 40 ° C. in summer. 20 ° C. to 40 ° C. is a temperature range suitable for the growth of microorganisms. The fish caught is boiled and sterilized once, but the heat-resistant spores remain without being killed. Since the thermostable spore bacteria are the temperature range where the bacteria grow most at around 35 ° C., the number of dried bacteria mechanically dried at a temperature of 40 ° C. or less is 10 ⁶ / g to 10 ⁷ / g. It becomes a lot of things.

  As raw materials of processed foods, those with a large number of general viable bacteria tend to be avoided because they are not manufactured under a sanitary environment. Therefore, when using boiled dried food as a raw material for processed foods, it is generally sterilized by treating with steam at 100 ° C. for about 30 minutes to 1 hour before use so that the number of viable bacteria falls below a certain level. However, there are problems of deterioration in storage stability due to an increase in water content of the product and deterioration in flavor due to heating. On the other hand, it is disclosed that the above-mentioned problems can be solved by performing a drying treatment after steam sterilization (see, for example, Patent Document 1). The roasting process imparts an original scented odor and greatly changes the flavor. Moreover, although it is disclosed that microorganisms can be completely sterilized without impairing fragrance and flavor by retort treatment (see, for example, Patent Document 2), flavor change due to high-temperature heat treatment is unavoidable.

JP-A-3-27240 JP 2001-159 A “Wisdom of Traditional Food”, Shibata Shoten, 1993, p. 75

  As described above, when the number of boiled dried common bacteria used for processed food is large, it cannot be used unless sterilized by secondary processing such as steam sterilization or retort sterilization. Moreover, if the heat treatment is performed to such an extent that the heat-resistant spore bacteria can be sterilized, the flavor deterioration of the boiled is inevitable.

  In view of such circumstances, the present invention provides a method for producing low-boiled dried sardines that do not require secondary processing for sterilization, have a low number of general viable bacteria, and have a good shape and shape.

  ADVANTAGE OF THE INVENTION According to this invention, in the manufacture of boiled dried food, the growth of the number of general viable bacteria can be suppressed by drying at a drying temperature of 50 ° C. to 80 ° C., and a product having a good shape and shape can be provided.

The present invention for solving the above problems has the following configuration.
1. In the manufacturing process of dried fish such as anchovy, sardine, urchin eagle, etc., a drying method is performed at a drying temperature of 50 to 80 ° C.
2. 2. The method for producing boiled dried food according to 1 above, wherein the temperature during drying is 60 ° C to 75 ° C.
3. The method for producing dried fish according to 1 above, wherein the temperature is increased from 50 ° C. to 80 ° C. at a rate of 10 ° C. or less per hour.

The present invention will be further described in detail.
The raw material used in the present invention is not particularly limited as long as it is a sardine such as anchovy, sardine, or urchin eagle, or a small fish that can be boiled, such as a horse mackerel, flying fish, or larvae. First, the raw material is sterilized by boiling in a hot water of 90 to 99 ° C. for 5 to 10 minutes depending on the fish size. The sterilized raw material is placed on a tray made of wire mesh so as not to overlap, and is moved into a dryer set at 50 ° C. in advance so that the center temperature of the fish body becomes 50 ° C. or higher. Next, the temperature in the dryer is increased at a temperature increase rate of 10 ° C. or less per hour, and drying is performed until the temperature of the boiled water becomes 20% or less at a constant temperature when the temperature in the dryer reaches 60 ° C. to 80 ° C. After that, the heat source is turned off and finish drying is performed only by air blowing. When the drying temperature is less than 50 ° C., microorganisms grow, which is not preferable. When drying is continued at 80 ° C. or more, a roasted odor is generated, which is not preferable. Moreover, putting the raw material after ripening in a high-temperature dryer exceeding 60 ° C. from the beginning, or a sudden increase in the drying temperature is not preferable because the raw material is broken. If the raw material after ripening is left unattended, the growth of heat-resistant bacteria will start after 6 hours. For this reason, it is preferable to dry in a drier whose temperature in the drier is 50 ° C. or higher as soon as possible after ripening, preferably within 2 hours.

  Bacteria detected as the number of general viable bacteria in dried boiled are heat-resistant spore bacteria that do not completely die even when boiled at 90 ° C. or higher, and the optimal temperature for growth is around 35 ° C. For this reason, it is necessary to dry the boiled food under a high temperature condition of 50 ° C. or higher, preferably 60 ° C. to 75 ° C., which can suppress the growth of heat-resistant spore bacteria. Since the boiled product thus obtained does not grow heat-resistant spore bacteria during drying, the number of general viable bacteria in the final product can be suppressed to 300 cells / g or less.

  About 100 g (4-5 g / 1 fish) of frozen anchovy is poured into 4 L of slightly boiling seawater and simmered for 7 minutes 30 seconds while maintaining a temperature of 95 ° C. or higher. Arrange them uniformly so that they do not overlap with each other, and put them in a hot air dryer (shelf dryer Yamato DT600T) set in advance at 50 ° C. After 40 minutes, when the center temperature of the fish reached 50 ° C., the temperature was raised at a rate of 7 ° C. per hour, and after 3 hours, when the temperature in the dryer reached 71 ° C., drying was performed at a constant temperature. 24 hours after the start of drying, the heat source of the dryer was turned off, and drying with a blower fan was performed for one day. The moisture after drying was 14%.

[Comparative Example 1]
Drying was carried out in the same manner as in Example 1 except that the temperature raising rate in the hot air dryer was raised at 7 ° C./1 hour for 5 hours and was kept constant at 85 ° C. The water content after drying was 12%.

[Comparative Example 2]
Sterilization was performed in the same manner as in Example 1, and drying was performed at a temperature in a hot air dryer of 40 ° C. for 24 hours. Thereafter, the heat source was turned off and drying with only a blower fan was performed for one day. The water content after drying was 15%.

[Comparative Example 3]
It was dried in the same manner as in Example 1 except that the temperature was raised at 15 ° C./1 hour for 1 hour and 40 minutes, and dried at a constant temperature when the temperature reached 75 ° C. The water content after drying was 13%.

  Table 1 shows the general viable cell count, flavor, and appearance inspection results of the boiled dried fish prepared in Example 1 and Comparative Examples 1, 2, and 3.

Claims (3)

  In the manufacturing process of dried fish such as anchovy, sardine, urchin eagle, etc., a drying method is characterized in that the drying temperature is 50 ° C to 80 ° C.   The temperature at the time of drying is 60 to 75 degreeC, The manufacturing method of the boiled-boiled food of Claim 1 characterized by the above-mentioned. The method for producing boiled raisins according to claim 1, wherein drying is performed at a rate of temperature increase from 50 ° C to 80 ° C at 10 ° C or less per hour.