A kind of countercurrent extraction method of stevia leaf

Abstract

The invention discloses a counter-current extraction method for stevia rebaudian, which comprises the following steps: (1) using a cyclone separator for separating and removing light impurities from stevia rebaudian, using a wind power stone remover for removing heavy impurities, crushing stems and then performing multi-level counter-current extraction; (2) in a multi-level counter-current extraction process, extracting the materials at each level and then squeezing water; performing next level of extracting and squeezing on the squeezed material, returning the water squeezed at each level and extracting at the level; (3) in the multi-level counter-current extraction process, using new solvents as all the extraction agents for the latest level extraction; taking extract liquor generated from each level of extraction as the extract liquor for the superior extraction; obtaining the extraction liquor generated from level-1 extraction as final extraction liquor of stevia rebaudian. According to the invention, the pretreatment operation is performed for ensuring the basic constant characters of the materials for extraction and ensuring the stability of the subsequent production. Meanwhile, a multi-level squeezing system is added in the multi-level counter-current extraction system, so that the water consumption is reduced, energy consumption is reduced and the yield of the products is increased.

Description

technical field

[0001] The invention belongs to the technical field of natural extract extraction, in particular to a countercurrent extraction method of stevia leaves. Background technique

[0002] Stevia (also known as stevia) is a dicotyledonous plant, a perennial herb of the Compositae family, native to South America, and introduced and planted in my country in the early 1980s. The leaves of stevia rebaudiana (that is, stevia leaves) contain 6 to 12% steviol glycosides and have been used to extract stevia sugar. Stevioside is a food additive (sweetener) extracted from the leaves of the Compositae plant Stevia rebaudiana. It is currently the only high-sweet, pure natural sweetener. The "third sugar source" has the advantages of safety, low calorific value and health care.

[0003] my country's stevia planting areas are relatively extensive, including Gansu, Inner Mongolia, Heilongjiang, Jiangxi, Shandong, Xinjiang and other places. Due to different climate and other con...

Examples

Embodiment 1

[0020] Embodiment 1: The countercurrent extraction method of the stevia leaves adopts the following specific techniques.

[0021] The stevia leaves are subjected to secondary countercurrent extraction after pretreatment, wherein the primary extraction temperature is 90°C, the secondary extraction temperature is 100°C, and the overall extraction material-to-liquid ratio is 1:6. The yield of the stevioside content of the obtained extract was 99.17%.

Embodiment 2

[0022] Embodiment 2: The countercurrent extraction method of this stevia leaf adopts the following specific process.

[0023] The stevia leaves are pretreated and subjected to three-stage countercurrent extraction, wherein the primary extraction temperature is 70°C, the secondary extraction temperature is 75°C, and the third extraction temperature is 80°C, and the overall extraction material-to-liquid ratio is 1:10. The yield of the stevioside content of the obtained extract was 99.93%.

Embodiment 3

[0024] Embodiment 3: The countercurrent extraction method of this stevia leaf adopts the following specific process.

[0025] The stevia leaf is subjected to four-stage countercurrent extraction after pretreatment, wherein, the first-stage extraction temperature is 30°C, the second-stage extraction temperature is 33°C, the third-stage extraction temperature is 36°C, and the fourth-stage extraction temperature is 39°C. for 1:15. The yield of the stevioside content of the obtained extract was 99.72%.

technical field

[0001] The invention belongs to the technical field of natural extract extraction, in particular to a countercurrent extraction method of stevia leaves. Background technique

[0002] Stevia (also known as stevia) is a dicotyledonous plant, a perennial herb of the Compositae family, native to South America, and introduced and planted in my country in the early 1980s. The leaves of stevia rebaudiana (that is, stevia leaves) contain 6 to 12% steviol glycosides and have been used to extract stevia sugar. Stevioside is a food additive (sweetener) extracted from the leaves of the Compositae plant Stevia rebaudiana. It is currently the only high-sweet, pure natural sweetener. The "third sugar source" has the advantages of safety, low calorific value and health care.

[0003] my country's stevia planting areas are relatively extensive, including Gansu, Inner Mongolia, Heilongjiang, Jiangxi, Shandong, Xinjiang and other places. Due to different climate and other con...

Examples

Embodiment 1

[0020] Embodiment 1: The countercurrent extraction method of the stevia leaves adopts the following specific techniques.

[0021] The stevia leaves are subjected to secondary countercurrent extraction after pretreatment, wherein the primary extraction temperature is 90°C, the secondary extraction temperature is 100°C, and the overall extraction material-to-liquid ratio is 1:6. The yield of the stevioside content of the obtained extract was 99.17%.

Embodiment 2

[0022] Embodiment 2: The countercurrent extraction method of this stevia leaf adopts the following specific process.

[0023] The stevia leaves are pretreated and subjected to three-stage countercurrent extraction, wherein the primary extraction temperature is 70°C, the secondary extraction temperature is 75°C, and the third extraction temperature is 80°C, and the overall extraction material-to-liquid ratio is 1:10. The yield of the stevioside content of the obtained extract was 99.93%.

Embodiment 3

[0024] Embodiment 3: The countercurrent extraction method of this stevia leaf adopts the following specific process.

[0025] The stevia leaf is subjected to four-stage countercurrent extraction after pretreatment, wherein, the first-stage extraction temperature is 30°C, the second-stage extraction temperature is 33°C, the third-stage extraction temperature is 36°C, and the fourth-stage extraction temperature is 39°C. for 1:15. The yield of the stevioside content of the obtained extract was 99.72%.

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