JP2002347732A - Glass bottle for use in hot packing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a glass bottle for the use in hot packing, which increases the cooling speed of liquid contents to keep it fresh so as to prevent the taste and quality of the contents from deteriorating. SOLUTION: A constriction is provided on the body of the bottle for the use in hot packing. The constriction enhances the convection of the liquid contents around the constricted part of the bottle, improving heat exchange between the lower and upper parts of the bottle. As a result, the temperature of the upper part of the bottle can be particularly quickly lowered so that the cooling speed of the contents is increased in total.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass bottle filled with a high-temperature liquid content, and more particularly to a glass bottle having a constricted shape for increasing a cooling rate of the content.

[0002]

2. Description of the Related Art In a product in which a glass bottle is filled with a liquid content such as a juice drink or milk, and the mouth of the bottle is sealed,
For sterilization, a method is used in which the liquid content is filled in a glass bottle while keeping the temperature high, and then the liquid content inside the bottle is cooled from outside the bottle. Such a method of filling the liquid content while keeping the temperature high is called "hot pack". With regard to glass bottles used in this hot pack, conventionally, straight bottles having a bottle body having a small body have been mainly used.

[0003]

However, in the conventional straight bottle, the cooling rate of the contents is slow, and particularly, the temperature in the upper part of the bottle is slow to decrease. If the cooling rate is low, there is a problem that the freshness, taste and quality of the contents are impaired. As described above, the freshness, taste, and quality of the contents are closely related to the cooling rate. Therefore, a technique for increasing the cooling rate even slightly has been desired.

The present invention promotes the convection of liquid contents filled in a bottle and promotes heat exchange between the upper part and the lower part of the bottle, thereby increasing the cooling rate of the entire bottle and refreshing the contents. The purpose is to maintain and prevent the taste and quality from dropping.

[0005]

SUMMARY OF THE INVENTION The present invention relates to a glass bottle used for a hot pack in which a liquid content is filled at a high temperature, wherein the glass bottle has a constricted portion in a bottle body. is there. By providing the neck portion in the body portion, the flow rate of the liquid content at the location of the neck portion is increased, and heat exchange between the lower portion and the upper portion of the bottle is promoted.

That is, in the glass bottle used for the above-mentioned hot pack, the high-temperature liquid content filled in the bottle is gradually cooled by cooling from the outside of the bottle. At this time, inside the bottle, the content having a low temperature flows downward along the inside of the wall surface of the bottle, and a convection occurs in which the content having a high temperature flows upward through the vertical center portion of the bottle. This results in heat exchange between the lower and upper parts of the bottle. If a constricted part is provided in the bottle body, the cross-sectional area will be smaller at the constricted part, even though the flow rate that rises from the lower part to the upper part in the vertical center part of the bottle and is almost the same, will be smaller, Thus, the flow velocity at the constricted portion becomes large. This promotes heat exchange between the lower and upper portions of the bottle because the convection of the liquid contents inside the bottle is generally faster. Therefore, the cooling rate increases.

Such effects differ depending on the height position and the diameter of the constricted portion. First, the ratio of 1: 0.85 to 0.95: 0.97 to 1.03 is suitable for the maximum trunk diameter of the bottle hem, the minimum trunk diameter of the constricted part, and the maximum trunk diameter of the bottle shoulder. . If the minimum waist diameter of the constricted part is significantly smaller than the maximum waist diameter of the shoulder or hem, the constricted part becomes convective resistance and convection is impeded, and conversely, the minimum waist diameter of the constricted part and the shoulder Alternatively, if the difference from the maximum body diameter of the skirt portion is too small, the convection promoting effect of the constricted portion decreases. It is desirable that the maximum body diameter of the bottle hem and the maximum body diameter of the bottle shoulder are substantially equal to each other, but even if there is a difference of about 3%, the influence on the convection promoting effect is small.

Next, it is desirable that the ratio of the height of the bottle main body to the height of the constricted portion up to the minimum body diameter is 1: 0.30 to 0.45. If the height of the constricted portion is too high, the reversal from the central ascending flow to the outward descending flow is hindered by the constricted portion that is too high. This is because the inversion from the flow to the upward flow in the center is inhibited by the constricted portion that is too low, and the convection promoting effect of the constricted portion is reduced.

In the present invention, the skirt portion means a portion below the constricted portion, and the shoulder portion means a portion above the constricted portion.

[0010]

Embodiments of the present invention will be described below in more detail with reference to the drawings. 1 to 3 show side views of Examples 1 to 3 of the constricted bottle according to the present invention. The dimensions of these bottles are as shown in Table 1 below. The bottles of Examples 1 to 3 are all round, and the horizontal sections of the shoulder, the constricted portion, and the hem are all circular. Various types of constricted bottles having different bottle heights and different heights and diameters of constricted portions were analyzed, and Examples 1 to 3 are some of these. Here, the analysis result will be described only for the first embodiment, but the results of the same tendency as the first embodiment are obtained for the second and third embodiments.

[Table 1]

The analysis was conducted for the purpose of comparing the cooling rates of the contents of the constricted bottle of Example 1 and the conventional straight bottle having a cylindrical shape. This straight bottle is formed by removing the constricted portion of the bottle of the first embodiment into a small body, and the height, the maximum diameter of the body portion, the maximum diameter of the hem portion and the like are the same as those of the first embodiment. First, both bottles were filled with a liquid content at a temperature of 90 ° C., the upper and lower surfaces of the content were insulated, and the bottle shoulder was cooled by showering with cold water. At this time, the ambient temperature was kept at a constant temperature of 25 ° C. Use 20% sugar water for liquid contents, bottle thickness 2m
m. In this way, the upper part, middle part,
The temperature of the liquid contents and the flow of the liquid contents of each bottle were analyzed at every lower part every 50 seconds from the start of cooling.

FIG. 4 and FIG. 5 both show the flow of the liquid contents 5 minutes after the start of cooling. FIG. 4 shows a constricted bottle of Example 1, and FIG. 5 shows a conventional straight bottle. In the figure, the flow of the contents is indicated by an arrow, and the size of the arrow indicates the size of the flow. Comparing the flow of the contents of the two bottles, the bottle of Example 1 has a large flow velocity that rises from the lower part to the upper part in the vertical central part of the bottle at the constricted part position. In addition, it can be seen that the downward flow on the bottle wall side also increases with this. On the other hand, in a straight bottle, there is almost no portion where the flow velocity is large in the ascending flow, and the flow is a similar small flow at any point. In the bottle of Example 1, the flow rate rising from the lower part of the bottle to the upper part is almost the same as that of the straight bottle, but the provision of the constricted part makes the cross-sectional area at the constricted part smaller than the straight bottle. As a result, the flow velocity at this position is increased. This promotes and complicates the convection of the liquid in the bottle, mixing the high and low temperature liquids well and promoting heat exchange.
4 and 5, it can be seen that the convection is promoted by the constricted portion in Example 1 in FIG. 4 and the contents are well mixed. Thereby, the heat exchange of the contents is promoted.

FIG. 6 is a graph showing the temperature change in each part of both bottles until 10 minutes elapse from the start of cooling based on the analysis values obtained by the above analysis. In this graph, the solid line represents the constricted shape bottle of Example 1, and the dotted line represents the conventional straight bottle. Also, "up" in the graph
"Shoulder" means the shoulder of the bottle, "middle" means the central body or neck of the bottle, and "bottom" means the hem of the bottle. As shown here, the bottle of Example 1 has a higher cooling rate than the straight bottle at any of the upper, middle, and lower positions, and the content is quickly cooled. This is related to the rate of convection of the contents, as described above. That is, in the constricted-shaped bottle of the first embodiment, the provision of the constricted portion increases the flow velocity of the contents, thereby promoting heat exchange.
In particular, the cooling rate immediately after the start of cooling is remarkably fast, but such rapid cooling can maintain the freshness of the contents and prevent the taste and quality from being impaired.

The difference between the cooling rates is most apparent at a point in time after 5 minutes have elapsed from the start of cooling. The temperature distribution at the top, middle, and bottom of each bottle at this point is shown in FIGS. 4 and 5. The temperature of each part of the bottle of Example 1 was 56.0 ° C., 52.0 ° C., 45.0 ° C. from the top.
° C, the straight bottle is 63.0 ° C from the top,
57.0 ° C and 47.0 ° C. Thus, 5
At the elapse of the minute, the bottle of Example 1 has a considerably lower temperature of the contents at each part than the straight bottle. In addition, the average temperature of the liquid content after 5 minutes has elapsed is
Example 1 49.8 ° C. for bottles and 5 for straight bottles
5.2 ° C. The temperature of the contents of the bottle of Example 1 is much lower than that of the bottle as a whole. Comparing the temperature difference between the two parts, the lower part (bottom part) of the bottle
The temperature difference between the two at the upper part (shoulder) of the bottle is as large as 7 ° C. as compared with the temperature difference between the two at 2 ° C.
This is also reflected in the temperature distribution. Comparing the temperature distributions of FIG. 4 and FIG. 5, as shown in FIG. In other words, it can be seen that the rising flow velocity is large at the constricted portion position, which promotes cooling of the upper portion of the bottle.
From these results, it can be seen that the constricted bottle has an effect of increasing the cooling rate particularly in the upper part of the bottle. The temperature in the upper part of the bottle has a great influence on the taste and quality of the contents. Therefore, the constricted-shaped bottle of the first embodiment can rapidly cool the temperature of the upper portion, thereby further improving the effect of preventing the taste and quality of the contents from being impaired.

[0015]

According to the glass bottle used in the hot pack of the present invention, the provision of the constricted portion increases the flow velocity of the contents at the constricted portion and promotes the convection. Heat exchange is promoted, and the temperature of the contents can be rapidly lowered. In particular, the cooling of the upper part of the bottle is accelerated compared to a straight bottle. This allows
It can maintain the freshness of the contents and prevent the taste and quality from being impaired.

[Brief description of the drawings]

FIG. 1 is a side view of a glass bottle according to a first embodiment of the present invention.

FIG. 2 is a side view of a glass bottle according to a second embodiment of the present invention.

FIG. 3 is a side view of a glass bottle according to a third embodiment of the present invention.

FIG. 4 is an explanatory diagram of the flow of the contents and the temperature distribution of the glass bottle of Example 1 after a lapse of 5 minutes from the start of cooling.

FIG. 5 is an explanatory diagram of the flow of the contents of the straight bottle and the temperature distribution after a lapse of 5 minutes from the start of cooling.

FIG. 6 is an explanatory diagram of a temperature change with time of the glass bottle and the straight bottle according to the first embodiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Glass bottle 2 Shoulder part 3 Constriction part 4 Hem part 11 Glass bottle 12 Constriction part 21 Glass bottle 22 Constriction part

Claims (3)

[Claims] 1. A glass bottle used for a hot pack for filling a liquid content at a high temperature, wherein the glass bottle has a constricted portion in a bottle body. 2. The glass bottle according to claim 1, wherein the maximum body diameter of the skirt portion, the minimum body diameter of the constricted portion, and the maximum body diameter of the bottle shoulder are 1: 0.85 to 0.95: 0. .97-1.
A glass bottle used for a hot pack, characterized in that the ratio is 03 3. The glass bottle according to claim 1, wherein the height of the bottle body and the height up to the minimum waist diameter of the constricted portion are in a ratio of 1: 0.30 to 0.45. Glass bottle used for hot pack