JPS6160075B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an extraction method for efficiently extracting a high-quality extract from guava leaves. Guava leaves have been decocted and an aqueous solution has been drunk in China since ancient times. In recent years, it has been attracting attention in Japan as it has been discovered to be effective against diabetes, high blood pressure, constipation, obesity, diarrhea, etc. Because of these effects, it is thought that it contains ingredients useful for maintaining health, and the number of people who drink it not only for the treatment of diseases but also for so-called health purposes is increasing. However, the method of brewing and drinking over a long period of time is troublesome and difficult for most drinkers.
Therefore, it is desirable to extract extract components and provide them in a form that is easily drinkable by anyone and suitable for distribution. However, in the conventional extract obtained from an extract extracted only with water, there is a risk that the components may change during the process of heating at high temperature for a long time and concentrating under reduced pressure. Moreover, industrial production requires large amounts of water and large-scale equipment.
Furthermore, since this method does not extract water-insoluble components such as essential oils, only a bitter extract lacking aroma and flavor can be obtained, and it cannot be said to be an appropriate method. The present inventors investigated various methods for efficiently extracting extracts with good flavor and no bitterness, and found that the extraction process was carried out under certain conditions using a water-primary alcohol or lower ketone mixture as the extraction solvent. I found it to be appropriate. That is, the method of the present invention consists of pulverizing dried guava leaves, extracting them in a mixture of water and primary alcohol or lower ketone at 50°C to 80°C, and concentrating the filtrate under reduced pressure. The mixing ratio of the liquid mixture used in this method is preferably in the range of 1:1 to 3:7 so as to sufficiently elute water-soluble components and alcohol-soluble components. When adding 2 to 4 times the weight of this mixture to dried guava leaves and heating and extracting at a temperature of 50℃ to 80℃, the hot alcohol acts on the tissue cells and accelerates the elution of the extract, so the reflux temperature is not always necessary. Not only does it not need to be maintained, it can be extracted in a short time using a small amount of solvent. Filter the extract under reduced pressure,
If the mixture is added to the residue and processed again, the extract can be extracted more completely. Extract liquid at 40-50℃
Concentrate under reduced pressure at 100-200 mmHg. The solvent is easily distilled out as an azeotropic mixture of water and primary alcohol or lower ketone, leaving a highly pure extract without any change in components during concentration. The liquid extract has an aroma and can be used as is, but it can be vacuum dried or freeze-dried to obtain a powder extract. This powdered extract is easily soluble in water, has an aroma, and can be drunk without the bitter taste of a decoction. The first feature of the method of the present invention is that by also extracting alcohol-soluble components, it is possible to obtain an extract containing aromas and useful components that are completely absent from conventional decoctions. The second feature is that the presence of alcohol accelerates the elution of the extract components, so it can be processed at low temperatures and in a short time, resulting in a high yield of high-quality extract with no change in components and no bitterness. The third feature is that extraction can be carried out efficiently with a small amount of solvent, making the apparatus compact and suitable for industrialization. As described above, when the method of the present invention is used, a high-quality, fragrant extract can be extracted at low temperatures in a short time with a high yield, and the amount of solvent can be reduced. Since the extract extracted by the method of the present invention contains the useful components of guava leaves as they are, it has a wide range of uses as a health drink, health food, and pharmaceutical raw material. Next, the method of the present invention will be explained in more detail using Examples and Reference Examples. Example 50 g of dried guava leaves are crushed, 200 ml of a 1:1 mixture of water and ethyl alcohol is added, and the mixture is heated at about 80° C. for 1 hour. Filter under reduced pressure with filter paper, add 100 ml of the mixed solution to the residue, re-extract, and combine the filtrates and concentrate under reduced pressure at 40-50°C and 100-200 mmHg to obtain a liquid extract.
Obtained 30ml. This was vacuum dried until the water content was 5% or less to obtain 10 g of powder extract. Yield on dry leaves is 20%. The analysis results of the above powder extract are shown in Table 1-Column A. Reference example: Crush 50g of dried guava leaves, add 400ml of water,
Heat at 95-100°C for 1 hour. Treated as in Example, re-extracted with 200 ml of water, and combined the filtrate to 70
Concentration under reduced pressure at ~80°C and 230-355 mmHg yielded 23 ml of liquid extract. This was vacuum dried until the moisture content became 5% or less to obtain 7 g of powder extract.
The yield on dry leaves is 14%. The liquid obtained by diluting this powder extract with water had a strong bitter taste and no aroma, unlike that of the example. The analysis results of the above powder extract are shown in Table 1-column B. 【table】

Claims (1)

[Claims] 1. To extract the extract from guava leaves, dry guava leaves are crushed, water-primary alcohol or lower ketone mixture is added, heated to 50°C to 80°C, and the filtrate is depressurized. A method for extracting guava leaf extract, which is characterized by lower concentration. 2. The method for extracting guava leaf extract according to claim 1, wherein the mixing ratio of water and primary alcohol or lower ketone mixture is 1:1 to 3:7.