INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes ELECTRODIALYSIS MEMBRANES (Oeno 29/2000)
1. OBJECTIVE, ORIGIN AND SCOPE OF APPLICATION
An electrodialysis membrane is a thin, dense, insoluble wall
composed of a polymer material that is permeable to ions. When placed between two solutions, it allows the selective transfer of ions from one solution to the other when acted upon by an electric field.
The membrane pair consists of a cationic membrane and an anionic
The cationic membrane is a polymer which allows the preferred flow
of cations, in particular the K+ and Ca++ cations.
The anionic membrane is a polymer which allows the preferred flow
of anions, in particular tartrate anions.
Electrodialysis membranes are used to stabilize wine in the event of
2. COMPOSITION
The cation-exchange membrane that can be used is a styrene-
divinylbenzene copolymer which carries sulfonic functional groups.
The anion-exchange membrane that can be used is either: A styrene-divinylbenzene copolymer which carries quaternary
A quaternary ammonium-divinylbenzene copolymer. Electrodialysis membranes used for tartaric stabilization in wine
2.1. They should be manufactured in accordance with the good
manufacturing practices for the substances enumerated in :
2.1.1 Annex 1 pertaining to materials placed in contact with
2.1.2. Annex 2 and Annex 3 pertaining to ion-exchange resins
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes 2.2. They should be prepared to serve their intended function, in
accordance with the instructions of the manufacturer or supplier.
2.3. They should not release any substance in a quantity which
poses a human health threat or which alters the taste or odor of foodstuffs.
2.4. In use, there should be no interaction between the constituents
of the membrane and those of the wine that could form new compounds in the product that could produce toxicological consequences.
The stability of new electrodialysis membranes shall be established
using a simulator which reproduces the physicochemical properties of wine, in order to study the migration of certain substances given off by the electrodialysis membrane.
The proposed experimental method is as follows: Composition of the simulator: This is an hydro-alcoholic solution with the pH and conductivity of wine. It is composed of
Distilled water: quantity sufficient for 100 liters
This solution is used to test migration in a closed circuit on a live
electrodialysis stack (1 volt/cell) in a proportion of 50 liters/m2 of anionic and cationic membranes until the solution is 50% demineralized. The effluent circuit is activated by a 5 g/l potassium chloride solution.
The migrating substances tested for in the simulator and in the
The organic molecules forming a constituent of membrane and which can migrate into the treated solution will be quantitatively analyzed.
A specific determination for each of these constituents will be carried
out an approved laboratory. The content in the simulator must be less than the total, for all compunds analyzed at 50 µg/l.
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
Generally, the rules governing materials used in contac with
foodstuffs shall also apply to these membranes.
3. LIMITS ON USE
The membrane pair used for tartaric wine-stabilizationprocessing
using electrodialysis is specified in such a way that:
- the pH reduction in the wine is no greater than 0.3 pH units ; - volatile acid reduction is less than 0.12 g/l (2 meq. expressed in
- electrodialysis-based processing does not affect the non-ionic
constituents of the wine, in particular the polyphenols and polysaccharides ;
- the diffusion of small molecules such as ethanol is reduced and
does not lead to a reduction of alcohometric content greater than 0.1%. 4. CONDITIONS OF USE
These membranes should be stored and cleaned using accepted
techniques and substances whose use is authorized for the preparation of foodstuffs.
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
List of monomers and other starting substances that can be used in the manufacture of plastic materials and devices designed to be placed in contact with foodstuffs, products, and beverages.
LIST OF APPROVED MONOMERS AND OTHER STARTING SUBSTANCES Restrictions E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
PM/REF N° Restrictions
epoxypropylic)ether of 2,2-bis(4-hydroxyphenyl) propane
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
PM/REF N° Restrictions
MQ = 1 mg/kg of PF or SML = non-detectable (DL = 0.02
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
PM/REF N° Restrictions
(expressed as NCO) SML(T) = 30 mg/kl alone or
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF N° Restrictions E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF N° Restrictions
0.020 mg/kg, including analytic tolerance)
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF N° Restrictions E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF N° Restrictions E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF N° Restrictions
(expressed as nCO) MQ(T) = 1 mg/kg in FP
(expressed as nCO) MQ(T) = 1 mg/kg in FP
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
A number of abbreviations or notations are given in Column 4. Their meaning is listed
DL = Detection limit of the analytical method.
For the purposes of the present directive, the expression « not detectable »
means that the substance will not be detected by the approved analytical method,
which is sensitive enough to detect it at the specified detection limit. If, however,
a method of this kind does not currently exist, an analytical technique possessing
performance characteristics suited to the specified limit may be used, while
awaiting the development of an approved method.
MQ = maximum permitted quantity of the « residual » substance in the material or article.
MQ(T) = maximum permitted quantity of residual substance in the material or article,
expressed as the total group or of the indicated substances(s).
For the purposes of this directive, « MQ(T) » means that the maximum permitted
quantity of the « residual » substance in the material or article should be
determined using an analytical method approved for the specified limit. If,
however, a method of this kind does not currently exist , an analytical technique
possessing performance characteristics suitable for determining the specified limit
may be used, while awaiting the development of an approved method.
SML = specific migration limit in the food product or the simulated food , unless otherwise
For the purposes of this directive, « SML » means that the specific migration of
the substance should be determined using an analytical method approved for the
specified limit. If, however, a method of this kind does not currently exist, an
analytical technique possessing performance characteristics suitable for
determining the specified limit may be used, while awaiting the development of
SML(T) = specific migration limit in the food product or simulated food, expressed as the
of the group or of the indicated substance(s).
For the purposes of this directive, « SML(T) » means that the specific migration of
the substance should be determined using an analytical method approved for the
specified limit. If, however, a method of this kind does not currently exist, an
analytical technique possessing performance characteristics suitable for
determining the specified limit may be used, while awaiting the development of
E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
List of substances used in the manufacture of adsorbant ion-exchange resins
used to condition foodstuffs. (Resolution AP (97)1 EC)
Substances assessed by an international organization PM/REF CASE RESTRICTIONS
============================================================ Monomers and other Starting substances n-butyl acrylate
Chemical Modifiers Carbonic acid, salts
Polymerization Additives Akylsulfonic acids (C8-C22) E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes
Substances that may be used provisionally to manufacture ion-exchange resins.
1. Substances not fully evaluated by an international organization PM/REF CASE RESTRICTIONS ======================================================= Monomers and other starting substances Ethylene glycol dimethacrylate
methylolpropane 2,3-epoxypropyl methacrylate
1,1,1-trimethylolpropane trimethacrylate
Chemical Modifiers N,N-dimethyl-1,3-diamino-
Polymerization Additives Polyvinyl alcohols
Partially hydrolyzed vinyl polyacetate 81260
2. Substances not evaluated by an international organization PM/REF CASE RESTRICTIONS =================================================== Monomers and other starting substances Dimethoxymethane
Chemical Modifiers Chlorosulfonic acid E-COEI-1-MEMELE INTERNATIONAL ŒNOLOGICAL CODEX Electrodialysis Memranes PM/REF CASE RESTRICTIONS =================================================== Monomers and other starting substances Methylic chloromethyl ether
Single-pass CO2-laser skin resurfacing in combination with cold air cooling. Efficacy and patient satisfaction of a prospective side-by- side study Christian Raulin, Hortensia Grema, Laserklinik Karlsruhe, Karlsruhe, Germany Word count: 1998 Correspondence address: Christian Raulin, M.D. Laserklinik Karlsruhe Kaiserstr. 104 Germany 76133 Karlsruhe www: Abstract: Ablative