JPH11169109A - Treatment of cereals - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a method for treating cereals to provide a heat denaturing treatment product of the cereals, hardly rotted, and having high preservation stability by dipping the cereals into water in the presence of lactic acid bacteria having nisin-producing abilities, and subjecting the dipped cereals to the heat denaturing treatment. SOLUTION: Cereals (e.g. rice, wheat, cone, soybean, red bean, broad bean, garden pea) are dipped into water in the presence of lactic acid bacteria having nisin-producing abilities (e.g. Lactococcus lactis ATCC 11454), and the dipped cereals are subjected to heat denaturing treatment (preferably at 15-35 deg.C for 10-50 hr) in the method for treating the cereals. The amount of the lactic acid bacteria added to the water is >=10<2> /ml, preferably 10<3> -10<7> /ml.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a method for treating cereals from which heat-modified cereals can be obtained with high storage stability.

[0002]

2. Description of the Related Art In general, various cereal-derived foods are obtained by immersing cereals as they are or after refining, immersing in water, swelling, and heat-modifying the cereals. Because it is a nutrient source, it easily rots.

[0003]

SUMMARY OF THE INVENTION An object of the present invention is to obtain a heat-denatured cereal which is hardly spoiled.

[0004]

Means for Solving the Problems The present inventors have made intensive studies to solve the above problems, and as a result, immersed cereals in water in the presence of a lactic acid bacterium having a nisin-producing ability, and then denatured by heating in a conventional manner. Then, the present inventor found that a heat-denatured cereal product that was hard to spoil was obtained, and based on this finding, completed the present invention.

[0005] That is, the present invention is a method for treating cereals, wherein the cereals are immersed in water in the presence of a lactic acid bacterium capable of producing nisin, and then denatured by heating in a conventional manner.

[0006]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below in detail.

[0007] In order to carry out the present invention, cereals are first immersed in water in the presence of lactic acid bacteria capable of producing nisin.

The lactic acid bacteria having nisin-producing ability used herein include any lactic acid bacterium having nisin-producing ability, such as Lactococcus lactis (Lac).
tococcus lactis) ATCC11454
And the like.

The amount of the lactic acid bacteria added to water is 10 ² /
ml or more, preferably 10 ³ to 10 ⁷ / ml.
If the amount is small, it is difficult to obtain the effect of preventing putrefaction. In addition, the immersion time must be extended.

The immersion is preferably carried out at a temperature of 15 to 35 ° C. for a time sufficient for the concentration of lactic acid bacteria capable of producing nisin to be 10 ⁸ / ml or more, for example, 10 to 50 hours. If the temperature is too low, the growth of lactic acid bacteria becomes slow, and it becomes difficult to obtain the effect of preventing rot. On the other hand, if the content is too high, the components of the cereal are eluted in water, and the utilization rate of the raw materials decreases, which is not preferable.

The grains used in the present invention include rice, wheat, corn, soybeans, red beans, silkworm beans, peas beans and the like. These may be used as they are, but are preferably used after whitening.

Hereinafter, the present invention will be described more specifically with reference to examples.

[0013]

EXAMPLES Example 1 Three types of cooked rice were produced in accordance with the methods shown in the following sections A, B and C, respectively. Category A (control cooked rice): 600 g of polished rice was washed by a conventional method, immersed in tap water at 30 ° C. for 30 minutes, and cooked with an electric rice cooker to obtain a control cooked rice. Category B (cooked rice of Comparative Example): Except for using a "dilute lactic acid aqueous solution of pH 4.0" to which "tap water" was added in place of "tap water" in the method of producing the cooked rice of the control described above. The same treatment was performed to obtain cooked rice of the comparative example. Category C (Rice cooked rice of the present invention): In the above-mentioned method for producing cooked rice as a control, “Nisin-producing lactic acid bacteria suspension water (Lactococcus lactis ATCC 1145) was used instead of“ tap water ”.
4, 2 × 10 ⁴ / ml) ”and the immersion time is 30
Except that the temperature was 24 hours, the rice cooked rice of the present invention was obtained.

Next, an antibacterial test was performed on each cooked rice by the following method. Table 1 shows the results.

[0015] From the results shown in Table 1, the rice cooked using tap water as the immersion water (control) and the cooked rice using the dilute lactic acid aqueous solution (comparative example) were treated at 30 ° C once they were contaminated by microorganisms. On the third day at 37 ° C. and rot, natto smell adheres and microorganisms grow to the order of 10 ⁷ to 10 ⁸ / ml, but cooked rice using nisin-producing lactic acid bacteria suspension water is once used. Even when contaminated with microorganisms and kept at 30 ° C. and 37 ° C. for 3 days, no off-flavor is generated, that is, no natto odor is attached, and the number of microorganisms is below the detection limit of 2000 cells / ml. It can be seen that corruption is prevented.

(Antibacterial test) As a test bacterium, a microorganism of the genus Bacillus isolated from a commercially available natto was used. 3 g / l of meat extract, polypeptone 5
g / l, medium containing 8 g / l of sodium chloride (nutrient
Agar (Agar Nutrient agar without agar)), aerobically cultivated, 15 μl inoculated into 15 g of test cooked rice in a sterile petri dish, 30 ° C. and 37 ° C.
For 3 days, and the odor and the number of bacteria were examined.

Table 1. Antibacterial test results of cooked rice immersed in nisin-producing lactic acid bacteria suspension water Classification Type of immersion water Culture conditions Number of bacteria after 3 days Odor (/ ml) Control section Tap water 30 ° C, 3 days Natto odor 2.9 × 10 ⁷ (pH 6.6) 37 ° C, 3 days Natto odor 1.5 × 10 ⁸ Comparative Example Dilute lactic acid aqueous solution 30 ° C, 3 days Natto odor 1.5 × 10 ⁷ (pH 4.0) 37 ° C, 3 days Natto odor 9.0 × 10 ⁷ Invention section Nisin producing ability 30 ° C., 3 days No off-flavor <2000 Lactic acid bacteria suspension water (pH 4.0) 37 ° C., 3 days No off-flavor <2000

[0018]

According to the present invention, it is possible to easily obtain a heat-denatured cereal product which is hardly spoiled.

Claims (2)

[Claims] 1. A method for treating cereal, comprising immersing the cereal in water in the presence of a lactic acid bacterium having a nisin-producing ability, followed by heat denaturation by a conventional method. 2. The method for treating cereals according to claim 1, wherein the water immersion is performed at 15 to 35 ° C. for 10 to 50 hours.