FR2525235A1 - PROCESS FOR EXTRACTING BEET JUICE - Google Patents

Abstract

1. A beet juice extracting process, in particular employing diffusion, of the type comprising previously treating beets cut into cossettes with calcium ions, characterized in that said prior treatment is effected by treatment of the cossettes with an aqueous solution of calcium saccharate, and a temperature less than 158 C.

Description

1. The present invention relates to a method

  beet juice extraction, in particular by diff-

  fusion. The processes of extraction of beet juice, formerly by pressure and now by diffusion, bring, with the juice containing sucrose, impurities and, in particular, pectic matters which, on the one hand, lower the purity, somewhere else,

  make subsequent filtration more difficult.

  This is the reason why different

  teurs have imagined to insolubilize pectic matter.

  To this end, they proposed carrying out a preliminary treatment of the beets cut into cossettes by

  lime usually in the form of milk of lime.

  Pectic materials are li-

  of galacturonic acid Part of the groups

  pementis carboxyl is methylated, part of the groups

  When hydroxyl is acetylated When treating pectic matter with lime, there are two reactions, first hydrolysis of esters with formation of methanol and acetate, then degradation of the

  glycosidic bonds with decomposition of the polymer.

  When the temperature rises, two

  Xth type of reaction On the other hand, if the temperature drops, it is the first reaction which predominates.

  and an insoluble calcium pectact is obtained.

  The prior art therefore consisted either in treating the beet chips with lime, generally in the form of milk, or in adding

  lime in water used for diffusion extraction.

  These processes have had no success because, at the temperature chosen for the action of lime on 2. the cellular juice of beets, the OH ions cut

  glycosidic bonds of carboxyl groups

  lics and destroy the pectic chain

  tion of pectins promoting the dissolution of hemicellulose tissue, this greatly reduces the stiffness of the pods, prevents percolation of the extraction liquid and makes subsequent pressing difficult

exhausted cassettes.

  The present invention aims to allow the fixing

  tion of calcium ions on the galacturonic chains of the beet cut into cossettes, prior to the extraction operation, in particular by diffusion,

  without destroying the glycosidic bonds.

  To this end, the present invention aims to

  throw a process for extracting beet juice,

  in particular by diffusion, of the type comprising a treatment

  beets cut into cossettes beforehand

  by calcium ions, characterized in that ef-

  performs said preliminary treatment by treating the cossettes with an aqueous solution of saccharate

  calcium, at a temperature below 15 'C.

  The calcium saccharate can be mono or calcium di-saccharate, provided that it is

  soluble under the reaction conditions In pra-

  tick, we prefer to use cal- monosaccharate

  cium. The reaction can, in practice, be carried out at a temperature of 0 to 150 C. Beyond this, there is a risk of

  decompose calcium saccharate.

  Aqueous solution of calcium saccharate

  can be obtained by dissolving salt in water.

  This solution advantageously contains from 1 to 15%

by weight of calcium saccharate.

  However, in an embodiment before-

  geux of the process, the calcium saccharate solution is made directly by 3. adding quicklime

to a diffusion juice.

  The invention is set out below in more detail using a drawing representing only one embodiment. In this drawing, the single figure is a diagram of an installation for implementing the method

according to the present invention.

  The installation shown diagrammatically in the single FIGURE comprises a processing device A The beets cut into pods enter in 1 into this device, for example percolating, which

  receives in 11 a saccharated juice at a low temperature

below 150 C.

  After reaction and calcium fixation, the cos-

  settes come out in 2 and are reheated in a heat exchanger

  their B, for example percolation using diffusion juice to

  700 C entering in 6 Cossettes which come out in 3 of 1 é-

  changer B are sent to a scalder C which re-

  receives in 4 a scalding juice (diffusion juice taken in the process and previously reheated> The juice-pod mixture heated to 70 ° C comes out in 5 from the scalder

  C and is sent to an extraction device by diff-

  shown fusion, where the diffusion takes place during

from 50 to 80 min.

  The pulps leaving the diffusion extraction apparatus undergo conventional pressing, for example by means of screw presses, bringing the content

  in dry matter of pulp more than 40%.

  Part of the juice withdrawn at 7 from exchanger B is brought at 8 to a heat exchanger D, where this juice is cooled to 40 C by means of incoming chilled water

in 15 and leaving in 16.

  The cooled juice leaving at 9 from the exchanger D is introduced into a reactor E in which there are 4.

  also introduces 10 quicklime powder.

  The reaction time is approximately 10 minutes.

  charaté which leaves in 11 is sent to device A as

indicated above.

  The juice leaving at 12 from the treatment apparatus

  A and the rest of the juice, discharged at 13, which is not pre-

  lifted from heat exchanger B for the preparation of sack juice-

  charaté are gathered in 14 and recovered.

  By way of example, 1000 kg of cassettes at 100 ° C. are introduced into the treatment apparatus A, in 1, and

  in 11, 227 kg of saccharated juice at 10 ° C (p H = 12.6).

  In 2, 1100 kg of calcium chips at 100 ° C. are obtained, which are introduced into the exchanger B. In addition, they are sent into the exchanger B, in 6, 1413 kg.

diffusion juice at 70 ° C.

  In 3, 1220 kg of calcium cassettes are obtained at 540 ° C. which are introduced into the scalder C with 2425 kg of scalding juice at 750 ° C. 3645 kg of mixture

  juices / caps at 70 ° C are sent, in 5, to the appliance

reil of diffusion extraction.

  From exchanger B, 1313 kg of diffuse juice come out

  fusion cooled to 330 C, of which 220 kg are sent in 8 to the exchanger D After cooling to 40 C, the 220 kg of diffusion juice are added with 7 kg of quicklime powder at 10 'C, in reactor E After reaction and treatment in the apparatus

  treatment A, 12, 127 kg of potash juice are discharged

  sic (after exchange of potassium ions with ions

  calcium) At 14, a total of 1220 kg of juice is drawn off.

  The method according to the invention makes it possible to improve the purity of the extraction juices, to reduce the extraction time (of the order of 20%) and to improve the

filterability of juices.

  The method according to the invention also makes it possible to improve the pressing conditions for spent pulps, thanks to the more rigid texture imparted by the fixation of calcium ions. Thus, 5 can be obtained.

  thanks to the process according to the present invention, pulp

  pressed weights with a dry matter content of more than 40%, while traditional methods allow pulp with a maximum dry matter content of 27 to 28% to be obtained.

  according to the invention therefore makes it possible to achieve economical

very important energy.

6.

Claims (3)

  1 Beet juice extraction process,   in particular by diffusion, of the type comprising a treatment   beets cut into cossettes beforehand   by calcium ions, characterized in that ef-   performs said preliminary treatment by treating the cossettes with an aqueous solution of saccharate   calcium, at a temperature below 15 'C.   2 Method according to claim 1, character-   laughed at in that calcium saccharate is mono- calcium saccharate.   3 The method of claim 1 or the   vendication 2, characterized in that the solution   aqueous calcium saccharate is obtained by ad-   addition of quicklime to a diffusion juice.