JPS63105637A - Production of milk made drink packed in sealed container - Google Patents

Abstract

PURPOSE:To obtain a high-quality, tasty product of long-period preservation type, by homogenizing raw material milk, heat-treating, packing into an air- impermeable container, sealing and further heat-treating. CONSTITUTION:Raw material milk such as whole milk, reduced milk, etc., is homogenized in such a way that >=90% fat spherules having <=1mu diameters. Before or after the treatment, the raw material milk is primarily heat-treated at 120-150 deg.C for <=5min and in F value of 2-50. The heat-treated milk is packed into an air-impermeable container, sealed and secondarily heat-treated at 110-130 deg.C for <=30min in a F value of 2.5-50. Two-stage heat-treatment is carried out in the range of sum of F values of the primary and the secondary heat-treatments of 2.5-60.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to a method for producing a dairy beverage packed in a sealed container that does not cause milk separation or deterioration even after long-term storage.

(Prior Art) In view of the fact that conventional bottled milk, tetra pack milk, etc. undergo milk separation and denaturation in a short period of time and cannot be stored at room temperature for more than 6 months, the present inventors As disclosed in the previous application, the raw milk is homogenized so that fat globules with a diameter of 1 μ or less account for 95% or more, and after filling the container and sealing it, the temperature is 115°C to 118°C. 15
We have developed a method for producing a milk beverage in a sealed container that can be stored for a long time without causing milk separation or deterioration even if left at room temperature for more than 6 months, with the combined requirement of heat treatment for ~20 minutes.

(Problems to be Solved by the Invention) The above proposed invention requires relatively strict homogenization treatment conditions as described above, but it is possible to ease the homogenization treatment conditions and produce a long-term storage product. desired. Further, according to subsequent observations, when the product obtained by the production method of the proposed invention is left at a high temperature such as in the summer, for example, 37 to 40°C, milk separation occurs relatively early within 6 months. There is a tendency for fat globules to float (separation) and deterioration, and when sold at a hot vendor, milk separation and deterioration occur within 1 to 2 weeks, and transportation, warehousing, sales, etc. teeth,
There was an inconvenience that the process had to be carried out at room temperature or below room temperature. Therefore, dairy beverages in sealed containers can be stored for more than 6 months even after being stored in a high-temperature environment in the summer, and will not cause milk separation or denaturation even if placed in a hot vendor for more than 1 to 2 weeks. It is desirable that it can be manufactured.

(Means for Solving the Problems) The present invention improves the above proposed invention and provides a method for producing a dairy beverage in a sealed container that satisfies the above requirements.
Homogenizing raw milk such as whole milk or reconstituted milk until fat globules with a diameter of 1 μ or less account for 90% or more, and heating the raw milk at 120 to 150°C before or after homogenization.
, within 5 minutes, perform the first heat treatment within the lower value range of 2 to 50, and then fill the impermeable container with the treatment name of the homogenization treatment and the first heat treatment, and then seal it 110~ 13
The second heat treatment is carried out at 0°C within 30 minutes at an F value of 2.5 to 50, and the total F value of the first heat treatment and the second heat treatment is 2.5 to 60. It is characterized in that these two stages of heat treatment are performed so that the temperature is within the range of .

(Function) According to Mizuyoshi, complete heat sterilization is carried out in two stages through primary heating and secondary heating under the above-mentioned specific conditions, and thermal denaturation of the protein components of milk beverages is carried out. Through the homogenization process, the viscosity is improved and the fat globules float lower than that of the previously proposed invention, even under high temperature environments.
At the same time, it is possible to produce a delicious, high-quality dairy beverage with a good flavor and without phenomena such as stalactite precipitation, floating fat globules, burnt odor, or browning due to heating, and it can be kept at room temperature for 6 months after summer 5 (37-40℃). Even after the above period, and even after being placed in a hot bender at 55 to 60° C. for about 1 to 2 weeks, the product remained a good quality product with good flavor and taste without rancidity or deterioration.

(Example) Next, an example of the present invention will be described in detail. The present inventors first processed raw milk (whole milk) using a homogenizer to
Homogenized to contain 90% of fat globules of micro size or less, heat sterilization is carried out by various heat sterilization methods such as the conventional LJHT heat sterilization method, or by varying the heating temperature and heating time. After sterilization, the cans were filled and sealed and their storage conditions were observed. After 1 to 3 months at room temperature, separation of fat, denaturation, burnt odor, browning, protein precipitation, etc. were observed. Heat sterilization method only before sealing the container
A product with a long shelf life of more than 6 months was not obtained. on the other hand,
Various attempts were made to increase the heating temperature and/or time in the previously proposed manufacturing method. That is, a so-called retort heat treatment was performed at 120° C. for 4 minutes or more, but the product had stalactite precipitation, fat floating, a burnt odor, browning, etc., and the desired product could not be obtained. The inventors believe that milk in sealed containers may be left in a hot bender for at least 1 to 2 weeks, or exposed to high temperatures during transportation or storage in a warehouse, such as during summer.
In order to obtain a product that can be stored stably without fat separation (floating), rancidity, or browning even after being exposed for months, it is necessary to simply kill the microorganisms before filling and sealing milk into containers. It has been found that the intended purpose cannot be achieved simply by heat sterilization or heat sterilization after sealing as with conventional retort food. In order to be able to store high-quality dairy products for more than six months at high temperatures, it was necessary to find new homogenization treatment conditions and heat treatment conditions. In particular, the floating and separation of fat after 6 months or more at high temperatures is determined by the degree of fineness of fat after homogenization, the viscosity of milk, the temperature regime of protein components such as albumin, globulin, and casein, and the degree of protein precipitation. Depending on the presence or absence of the product, browning of the product,
It is believed that the deterioration is caused by the microorganisms remaining in the sealed container and the enzymes that produce the microorganisms that remain after the microorganisms have died and gradually work. However, it is necessary to obtain a delicious product with good flavor and without browning or burnt odor.

We tried various heating conditions and methods to store the milk in a sealed container at high temperatures for more than 6 months, but as a result, we found that the homogenized milk
It is necessary to heat the product in two stages, before and after filling the container, and the desired product cannot be obtained with one heat treatment.
It has been found that if the milk develops a scorched odor, browns, or is not heated enough, the product milk will deteriorate and the purpose will not be achieved. Therefore, the heat history applied to the entire milk to be heated is also important, and only by setting the F value in the first and second heat treatments within a specific range can the desired milk in a sealed container be produced. I found out that I can get it.

To be more specific, raw milk, generally milk (whole milk), is processed using a homogenizer to reduce fat globules with a diameter of 1μ or less to 90%.
Homogenization treatment is performed to contain the above. This homogenization condition is more relaxed than the previously proposed homogenization condition of 95% or more fat globules with a diameter of 1μ or less, but by performing the two-step heating conditions described later, the fat floats to the surface. ,
Results were obtained that did not cause separation. This is because the whey protein contained in milk undergoes moderate thermal denaturation together with casein micelle phosphate, etc. through the two-step heating conditions, which increases the viscosity of milk and prevents the rise of fat globules. This is thought to be because it contributes to preventing the floating and separation of fat globules by preventing them from floating and separating them. The first heat treatment in the two-step heating process is to perform the whole milk, which has not been homogenized as described above, at 120 to 150°C within a temperature range of 5 to 50.

Specifically, 120°C, 2.6 minutes, F value 2 or 150
A first heat treatment is performed at a temperature of 50° C. for 4 seconds.

Below the lower limit of the three conditions of heating temperature, time, and F value,
Heat sterilization of components including heat-resistant components becomes insufficient, and if the heat sterilization is exceeded, burnt milk odor, browning, formation of stalactites, precipitation, etc. will occur. It has been found that if this primary heat-treated milk were to be filled and sealed in containers such as cans and left as is, the proteins would not be sufficiently denatured by heat and fat would float over time.

According to the present invention, it is important to perform the second heat treatment under the following conditions after performing the first heat treatment and filling and sealing the homogenized milk into a container such as a can.

That is, the filled and sealed milk is heated at 110 to 130°C and 30°C.
However, it is important to perform the second heat treatment within a range of 2.5 to 60, including the F value in the first heat treatment. As a result, a sealed product can be obtained in which protein-based components are moderately coagulated and fat does not float or separate even at high temperatures.

Furthermore, by overlapping the heating temperatures and times of the first and second heat treatments, it is possible to sufficiently heat sterilize the milk product and deactivate the enzymes without browning or burning the milk. Even if left in a hot bender for more than two weeks or stored at high temperatures in summer for a long period of time, no fat oxidation, protein precipitation, or browning will be observed, resulting in delicious milk with a good flavor. It could be stored stably.

Next, the following are comparative examples of cases in which the above-mentioned homogenization treatment conditions and primary and secondary heat treatment conditions of the present invention are satisfied, and cases in which the conditions are stored at high temperatures when any one of these conditions is lacking. show.

Example 1 After heating raw milk to 80° C. using a plate heater, the primary pressure of the homogenizer was set to 120 Kg/clIl, and the milk was homogenized so that 90% of the milk contained fat globules with a diameter of 1 μm or less. After heating the homogeneous hole to 140°C using a plate-type LJHTST device and taking a holding time of 15 seconds (F value 19.
4) Cooled to 90°C, filled into 200g cans, sealed, and sterilized in a retort at 115°C for 15 minutes (value -3,7).
Total F value = 23.1).

After storing this product for 1 week at 55°C and 6 months at room temperature, 10
When the cans were opened one by one, no separation or deterioration of the fat was observed, and the flavor was good.

Example 2 After heating raw milk to 138°C in a plate type UHTST device and taking a holding time of 12 seconds (F value 10)
After cooling to 80°C, the primary pressure of the homogenizer was increased to 120°C.
/cri The secondary pressure is 30 to 9/crl and the diameter is 1
Homogenization was performed so that 90% of the fat globules were smaller than μ. After filling and sealing the 20057 can with these homogeneous holes, it was placed in a retort for 12 hours.
Sterilized at 0°C for 13 minutes (F value 10) (total F value 20). After storing this canned milk at 55° C. for one week and at room temperature for six months, 10 cans each were opened. There was no separation or alteration of fat, and the flavor was good.

Example 3 Same as Example 1 except that the primary pressure of the homogenizer was set to 150'j/crI, the secondary pressure was set to 30 Kg/crj, and the fat globules with a diameter of 1 μ or less were homogenized to 95%. processed.

This product was stored at room temperature for 6 months, and after 6 months at room temperature, it was further stored at 55°C for 1 week, and then 10 cans each were opened, but no separation or alteration of fat was observed, and the flavor was good. .

Comparative Example 1 After heating raw milk to 60°C, the primary pressure of the Vomogenizer was set to 100'j/cIi and the secondary pressure was 50 to 9/ci, so that the fat globules with a diameter of 1 μ or less accounted for 85%. and then treated in the same manner as in Example 1. When the can was opened after 6 months at room temperature, fat was noticeable on the surface, and it was determined that there was a problem with its practical use.

Comparative Example 2 The holding time in Example 1 was 30 seconds (F value = 38.7), and the retort sterilization was performed at 123°C for 25 minutes (F value -
386) (total F value -77,3) was opened immediately after production and after 6 months at room temperature, but there was floating of fat and precipitation of protein, deterioration of color (browning) and deterioration of flavor. was recognized.

Comparative Example 3 The UHTST heating temperature in Example was set to 137°C, the holding time was set to 4 seconds (F value -2,6), and the retort sterilization was changed to 124.56C for 25 minutes (F value = 55). When the can was opened immediately after (total F value -57.6) and after 6 months at room temperature, significant milk separation was observed, browning was significant, and the flavor was significantly deteriorated.

Comparative Example 4 In Example 1, the UHTST heating temperature was changed to 138°C, the holding time was changed to 3 seconds ([value -2, 4)], and the retort sterilization was changed to 110°C for 5 minutes (F value = 0.4). (Total F value -2,8), 6 months at room temperature, 55
When we opened 10 cans each when stored at ℃, 1 can was opened when stored at room temperature.
Changes were observed in 1 out of 0 cans and 2 out of 10 cans when stored at 55. In addition, in the case where no denaturation occurred after 6 months at room temperature, fat floated to the surface.

Comparative Example 5 Processing was carried out by changing the UHTST heating temperature in Example 1 to 138°C, Boulding time to 70 seconds (F value -57), and retort sterilization to 110°C for 15 minutes (F value = 1.2). (F value = 58.2), room temperature for 6 months,
55℃ for 1 week.

Comparative Example 6 Processed by changing the UHTST heating temperature in Example 1 to 138°C, holding time to 2 seconds (F value -1, 6), and retort sterilization to 110°C for 15 minutes (F value -1, 2). (total F value -2,8), when 10 cans were opened after 1 week at 55℃ and 1 week at room temperature, 2 out of 10 cans when stored at 55℃ and 1 out of 10 when stored at room temperature showed deterioration. It was done.

Comparative Example 7 After heating raw milk to 80°C with a plate heater, the primary pressure of the homogenizer was set to 150 9/C#i and the secondary pressure was 30 Kg/cIIi to obtain 95 fat globules with a diameter of 1 μ or less.
%. This homogeneous hole is a 7-rate type t
The mixture was heated to 140°C using a JHTsT apparatus, and after a holding time of 8 seconds (F value -10), it was filled and sealed aseptically into cans. After storing this product at room temperature for 6 months, 10 cans each were opened and examined, and separation of fat was observed. Also, 1 at 55℃
When stored for a week, the flavor deteriorated.

Comparative Example 8 The homogeneous holes prepared in Comparative Example 7 were immediately filled into a can and sealed, and then heat sterilized at 115° C. for 15 minutes (F value -3,7).

This product was stored at room temperature for 6 months, but the flavor was good without any fat floating, deterioration, or browning. However, when stored at 55°C for one week, one out of ten cans deteriorated.

The test results of each sealed canned milk of the above Examples and Comparative Examples are shown in the table below.

161 The above embodiment of the present invention shows an example of producing canned pure milk containing only whole milk, but canned milk containing lecithin or milk containing vitamins may also be used. Processed milk in a paper container (31i! ) can also be applied.

(Effects of the Invention) According to the present invention, raw milk such as whole milk or reconstituted milk is homogenized until the proportion of fat globules with a diameter of 1 μ or less becomes 90% or more, and the process is carried out at 120 to 150°C for 50 minutes. Within "110~ after performing the primary heat treatment under the conditions of value 2 ~ 50
130℃, within 30 minutes, under the conditions of “value 2.5 to 50”
A dairy beverage in a sealed container is produced by performing a second heat treatment, but making sure that the sum of the F value of this second heat treatment and the F value of the first heat treatment is within the range of 2.5 to 50. Therefore, even if you leave it in a hot bender for more than a week or store it at a high temperature of 37 to 40 degrees Celsius in the summer for one to two months, it will not cause any inconveniences such as fat separation or deterioration, and will have a good quality flavor. It has the effect of obtaining a stable long-term storage product.

Claims (1)

[Claims] 1. Homogenize raw milk such as whole milk or reconstituted milk until fat globules with a diameter of 1μ or less account for 90% or more, and before or after homogenizing the raw milk,
The first heat treatment was performed at 0°C for 5 minutes within the F value range of 2 to 50, and the processed milk subjected to the homogenization treatment and the first heat treatment was filled and sealed in an impermeable container. After 110~
The second heat treatment is performed at 130°C for 30 minutes within the range of F value 2.5 to 50, and the total F value of the first heat treatment and second heat treatment is 2.5 to 60. A method for producing a dairy beverage in a sealed container, characterized by performing these two steps of heat treatment so that the temperature is within the range of .