JPS597419B2 - How to preserve tofu - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tofu preservation method that suppresses deterioration of tofu during its preservation.

Currently, the method of preserving tofu made using molded boxes is to preserve the tofu taken out of the molded box as it is or by enclosing it in a pack with water and immersing it in water in an aquarium for a predetermined period of time.

When storing tofu in cold water, 150 to 200 ml of cold water is required for 20,000 tofu (30 og/ton)/day, for example, for normal-sized tofu.

In particular, in the summer, the water temperature is high (for example, around 25°C), so it is necessary to use a method to lower the water temperature to a level that does not cause deterioration of the tofu (for example, around 5°C).

Cooling water using refrigeration equipment is an effective means of lowering this water temperature, but on the other hand, using refrigeration equipment requires a considerable amount of overhead, making it unprofitable as a product, so preserving tofu in the summer The reality is that this is a major bottleneck in this field.

In view of the above circumstances, the present invention has been developed to make it possible to preserve tofu easily and inexpensively, to extend the preservation time by suppressing the deterioration of tofu during preservation, and tofu that can be preserved without impairing the taste. The purpose is to provide a method for preserving

In order to achieve the above object, the present invention is a method of enclosing tofu obtained by the molded box method in a pack together with carbonated water.

The functions and effects of this invention will become clearer through the following experimental examples.

Experimental Example CI) Experimental Method: Add 60r of each of the following water to 1 block of tofu (300g).
/'Ll was used to encapsulate it in a pack, and each tofu-encapsulated Nosaku was stored at room temperature at 23° C. for a predetermined number of days.

The following tap water and carbonated water were used as the filling liquid.

A...Tap water (water temperature at the time of enclosing: 13°C) B...Carbonated water made by dissolving 1 liter of carbon dioxide gas in 1 liter of tap water (water temperature at the time of enclosing: 13°C) C...Supersaturation of carbon dioxide gas (water: Carbon dioxide gas = 125) Carbonated water (water temperature 13℃ when sealed) D... Carbonated water made from dry ice pellets approx. 5g/111 water (water temperature 5℃ when sealed) [Le Deterioration measurement of tofu (1) ) Judgment based on changes in appearance: Deformation, odor, and taste changes are sensory tested.

(2) Testing the number of groups of E. coli etc. using a membrane filter.

10 TLl of sample water was collected. (3) Sulfur compounds・
...Chromatography.

(4) The pH value indicates the pH value of the sealed water.

Last year's experimental results (stored at room temperature of 23℃) (IV) Discussion As for the taste, when comparing samples filled with tap water and samples filled with carbonated water, there was no perceived difference, but the sourness was proportional to the odor. It feels like it's increasing.

As a result of a sensory test, up to 10 out of 10 people did not perceive any sour taste in samples that did not detect any off-odor.

The reason for this is not clear. Considering the pH values, all samples except sample A tended to be alkaline from around the second day.

After that, as the number of days increases, it leans toward the acid side.

This is thought to be due to the aminocarbonyl reaction between unsaturated aldehydes produced by oxidation of lipids in tofu and proteins.

Discoloration and deterioration are largely influenced by common viable bacteria (yeast, aeruginosa), and if the bacterial colony i7) exceeds 1500, the color will turn brown and the taste will deteriorate.

The main cause of the odor is thought to be the synthesis of ammonia nitrogen by these common viable bacteria.

The odor due to sulfur was analyzed by gas chromatography, but since it was not detected, it is reasonable to assume that it is due to ammonia nitrogen.

The odor increases in proportion to the number of bacterial colonies.

The pH value is the concentration of carbon dioxide gas, and the lower the temperature of carbonated water, the more acidic the pH value becomes, and the more effective the bacteriostatic effect is.

From this, the pH value of carbonated water during storage is 4.5 to 5.5.
is preferred.

In addition, there was a concern that the pack would expand during storage, but no expansion was observed at all, and the pack instead showed a phenomenon of contraction.

This is thought to be caused by the protein in tofu.

According to this invention, by enclosing tofu in a pack together with carbonated water, deterioration of the tofu can be suppressed and the number of days it can be stored can be extended.

Therefore, advantages such as a significant reduction in overhead costs are brought about.

Claims (1)

[Claims] 1. A tofu preservation method characterized by enclosing tofu in a pack together with carbonated water.