RU2247735C2 - Method for preparing pectin from citrus husks - Google Patents

Abstract

FIELD: vegetable raw technology.

SUBSTANCE: invention relates to a method for isolating pectin from vegetable raw. Method for preparing pectin from citrus husks involves hydrolysis-extraction of a solid phase and separation of a liquid phase. Before hydrolysis-extraction a solid phase is extracted with acetone and liquid carbon dioxide successively under the above atmosphere pressure. The second extract is separated without pressure change followed by abrupt dropping pressure over a solid phase up to atmosphere value and feeding a solid phase to hydrolysis-extraction. Invention provides reducing loss of pectin being without deterioration of its organoleptic properties.

EFFECT: improved preparing method.

Description

The invention relates to a technology for the isolation of pectin from plant materials.

A known method of producing pectin from citrus squeezes, providing for their extraction with water, hydrolysis-extraction of the solid phase, separation of the liquid phase and its concentration or drying (L. Donchenko, Technology of pectin and pectin products. - M .: DeLi, 2000, p. 96- 105).

The disadvantage of this method is the high loss of pectin with an aqueous extract.

The technical result of the invention is to reduce the loss of pectin without compromising its organoleptic properties.

This result is achieved by the fact that in the method for producing pectin from citrus extracts, providing for their hydrolysis-extraction and separation of the liquid phase, according to the invention, before hydrolysis-extraction they are sequentially extracted with acetone and liquid carbon dioxide at a pressure above atmospheric, the second extract is separated without changing the pressure, then the pressure over the solid phase is sharply reduced to atmospheric with the direction of the solid phase for hydrolysis-extraction.

The method is implemented as follows.

Citrus squeezes, if necessary, are crushed (Donchenko L.V. Technology of pectin and pectin products. A textbook for university students. - M .: DeLi, 2000, p.96-105), and then extracted with acetone and the extract is separated by known methods (Bykova S . F. Theoretical and experimental foundations for creating a fundamentally new resource-saving technology for the production of vegetable oils. Abstract of thesis, Doctor of Technical Sciences, St. Petersburg: VNIIZh, p.21-26; Demchenko PP Improving the technology of extraction of oil from sunflower seeds. Abstract of a Candidate of Technical Sciences - L .: VNIIZH, 1982, 6-14), containing essential oils and glycosides with a bitter taste. Next, the solid phase is extracted with liquid carbon dioxide at a pressure above atmospheric pressure corresponding to the saturated vapor pressure of the extractant at the extraction temperature and the extract is separated without changing the pressure (Kasyanov G.I. et al. Processing of plant materials with liquefied and compressed gases - M .: AgroNIITEIPP, 1993, 40 s.). Residues of acetone pass into the extract, which excludes the further transition of acetone through the stages of the technological process and its entry into the target product. The pressure over the solid phase is sharply dumped to atmospheric. This leads to a sharp boiling of liquefied gas and explosive grinding of plant materials, accompanied by the destruction of cell membranes. Next, the solid phase is directed to hydrolysis-extraction.

Hydrolysis-extraction is carried out at parameters selected according to well-known recommendations (L. Donchenko. Technology of pectin and pectin products. - M .: DeLi, 2000, p.143-142) or calculated according to known dependencies (I. Ilyina. Scientific principles of technology modified pectins. - Krasnodar: SKZNIISiV, 2001, p. 88-156). Due to the preliminary destruction of cell membranes, the contact surface of the phases and the availability of protopectin substances for hydrolysis-extraction are increased. This reduces the duration of the process and reduces the possibility of deep hydrolysis and loss of pectin. After completion of the hydrolysis-extraction, the liquid phase is separated as the target product, which, if necessary, is concentrated or dried.

It should be noted that pectin substances are not soluble in either acetone or carbon dioxide, which excludes their loss with extracts and, accordingly, increases the yield of pectin substances in comparison with the closest analogue. Despite the fact that the initial pectin content in citrus squeezes is from 8.9 to 14.9% by dry matter, and the content of the water-soluble fraction removed according to the prototype and remaining according to the invention is about 33% (Donchenko L.V. Technology of pectin and pectin products - M .: DeLi, 2000, p.53, 97), the losses of pectin as a result of its deep hydrolysis can be estimated for the proposed method and the closest analogue according to known dependencies (Altunyan M.K. Kinetics of polysaccharide destruction in the process of producing pectin. Abstract of a Ph.D. snodar: CPI 1988).

The determination of the organoleptic properties of the products obtained by the proposed method and the closest analogue, carried out according to GOST 8756.1, did not allow to identify differences between them in any of the regulated indicators.

Thus, the proposed method can reduce the loss of pectin without compromising its organoleptic properties.

Claims (1)

A method of producing pectin from citrus squeezes, providing for hydrolysis-extraction of the solid phase and separation of the liquid phase, characterized in that before the hydrolysis-extraction of the solid phase is sequentially extracted with acetone and liquid carbon dioxide at a pressure above atmospheric, the second extract is separated without changing the pressure, then the pressure is the solid phase is sharply discharged to atmospheric with the direction of the solid phase for hydrolysis-extraction.