JPS58149665A - Preparation of ume (japanese apricot tree) juice - Google Patents

Abstract

PURPOSE:To prepare the juice of UME (Japanese plum) having excellent aroma, in a short time, in high efficiency, without lowering the taste and flavor of the UME fruit, by keeping the UME fruit at a specific high temperature for a definite time interval, and immersing the fruit in a concentrated sugar solution having a specific concentration under a specific temperature condition. CONSTITUTION:The harvested UME fruits are maintained at 35-45 deg.C for 3-7 days to make the pulp component easily extractable. The fruits are immersed in a concentrated sugar solution of 40-75% concentration and extracted at <=30 deg.C, preferably about 15 deg.C. The sugar is e.g. glucose, fructose, sucrose, lactose, dextrin, etc., and the extraction is carried out for <=15 days. The UME juice can be prepared by this process in a short time, in high efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for efficiently producing aromatic plum juice in a short period of time without impairing the flavor of fresh plum fruit.

Plums have a strong acidity and a high pulp content, so the pressed fruit juice must have an acid content of 3.5% or more and a pulp content (insoluble solids) of 94% or more according to the JAS (Japan Agricultural and Forestry Standards) fruit juice composition standards. It is considered a standard product and has a porridge-like appearance. This pressed fruit juice liquid is easy to use for solid processed foods such as processed plums and plum meat products, but it lacks transparency and is difficult to use for fruit drinks.
Furthermore, it is difficult to use because it has drawbacks such as precipitation after producing fruit drinks.

On the other hand, plum juice has long been produced as plum wine either domestically or industrially by an extraction method using a mixture of alcohol and sugar, and has been used as a refreshing fruit wine with a good flavor. The principle of Umedomari production is to utilize the semipermeable membrane properties of the pericarp of the plum fruit, and to utilize the irreversible extraction phenomenon of the osmotic pressure of the liquid mixture. Therefore, even if you use the osmotic pressure of the sugar solution after removing alcohol from this mixture,
It is possible to produce plum juice that does not contain alcohol.

Conventionally, plum juice using this extraction method is obtained by soaking plum fruit in a sugar solution and keeping it at about 15°C for about 40 days (Yoshihiro Komiyama fΦ: Yamanashi Prefectural Food Industry Guidance Center Research Report No. 6, 84)
~98 pages (1974)), it is an extracted fruit juice with a very good flavor, a refreshing sensation, and a fruity taste. However, with this method, as the extraction progresses, the concentration of the sugar solution decreases, the number of oxygen devices is small compared to the above-mentioned pressed fruit juice, and the extraction process is relatively long, so treatments such as alcohol spray sterilization are not used. However, it is not possible to prevent the growth of microorganisms, and it also has disadvantages such as electric lead pipes, labor costs, and historically low extraction tank turnover due to long-term extraction.

The inventors investigated a method of increasing the extraction temperature as a way to shorten the extraction period.
It was found that extraction was sufficient in 10 days at 40°C, but the extract turned brown significantly, impairing the flavor and appearance, and in some cases, the high extraction temperature actually exacerbated the spoilage caused by microorganisms. (Yoshihiro Komiyama et al.: Yamanashi Prefectural Food Industry Guidance Center Research Report No. 7, pp. 53-61,
1975).

Therefore, as a result of intensive research into ways to overcome the above-mentioned drawbacks, we found that if ume fruits are stored at high temperatures for a short period of time after harvesting, the pericarp tissue of the ume fruit changes, making it easier to extract the ume pulp components, which leads to a shorter extraction period. The present invention was completed by discovering that the salt can be significantly reduced.

That is, the present invention includes a first step in which plum fruits are held at a temperature of 35 to 45 degrees Celsius for 3 to 7 days, and a second step in which plum fruits are immersed in a high concentration sugar solution of 40 to 75% and kept at a temperature below 30 degrees Celsius. By repeating the two steps in sequence, the skin structure is changed so that the components of the plum fruit can be easily extracted with a high-concentration sugar solution, producing plum juice for drinks that is rich in aroma without impairing the flavor of fresh plum fruit. It was developed with the aim of efficiently manufacturing in a short period of time.

Next, the first and second steps of the method for producing plum juice according to the present invention will be explained in detail as follows.

<Step I> This is a step of storing plum fruits at a relatively high temperature of 35° C. to 4.5° C. for 3 to 7 days after harvesting. Conventionally, when storing fruit, the amount of respiration of the fruit is high in an environment where the storage temperature is high.
It is said that quality is significantly impaired due to large changes in components, but by storing plum fruits at a high temperature of around 40 degrees Celsius for a short period of about 5 days, the skin structure of plums changes so that pulp components can be easily extracted. This makes it possible to do so.

2nd process> Plum fruits stored at high temperature for a short period of time in the 1st process are heated to 40-75%
This is the process of extracting the components of the plum fruit by immersing it in a high-concentration sugar solution. It is necessary to perform the extraction at a temperature of 30°C or lower. Low-temperature extraction is desirable in order to improve the quality of extracted fruit juice and completely prevent microbial contamination, but extraction at too low a temperature requires a long period of time. If the extraction temperature exceeds 30°C, both flavor and color tone will deteriorate. The best extraction temperature is after 15°C.

As the sugars used for producing the high concentration sugar solution, monosaccharides or bisaccharides such as glucose, fructose, isomerized sugar, sugar, maltose, and lactose, as well as powdered candy, dextrin, and the like can also be used.

Note that the extraction is normally completed within at least 15 days.

Example: Immediately after harvesting Shirakaga plums from Kofu City, Yamanashi Prefecture, they were washed with water, drained, and wiped with a cloth to remove water droplets, then placed 700 g of plums in each of three 21-capacity simple pickle pots, and heated them at 15°C at 30°C. After 5 days of storage in a thermostat at 40°C and 40°C, these containers were taken out and 60% of the plums and the same ones were removed.
A sugar solution was added, the plums were pushed up so that they did not rise above the liquid level, and extraction was started at 15°C. Removed over time during extraction,
Extract liquid, acid, amino nitrogen and 400 mi! j The absorbance at a wavelength of microns was measured. In order to confirm the effectiveness of the method of the present invention, immediately after harvesting,
The same measurement was performed for the extract obtained by extraction with 0 U.

The above results are shown in Table 1. When extracted at 15°C after being stored at 40°C for 5 days after harvesting, the rate of increase in liquid volume and the extraction rate of components are extremely high, the progress of coloring of the extract is slow, and the flavor is was also good.

The plum juice obtained by the method of this invention has an extremely good flavor and contains no insoluble matter or alcohol, so it can be used as a flavor enhancer for any beverage or as a flavor improver. In addition, the extracted plum fruit can be eaten as is, and the pulp can also be crushed and used as a raw material for pasty or solid foods such as jam, plum paste, and plum sweets.

Claims (1)

[Claims] The first step of holding the plum fruit at a temperature of 35°C to 45°C for 3 to 7 days, and the second step of immersing the plum fruit in a high concentration sugar solution of 40% to 75% and keeping it below 30°C are repeated sequentially. A method for producing plum juice characterized by the following.