Final Recommendations 32nd Session ICUMSA 2021

Referee: Tim Thys (The Netherlands)

1. A collaborative study should be conducted to evaluate the use of a modified filtration (20 μm pore filter) in Method GS1‐24, Insoluble Solids in Raw Sugar by Depth‐Type Filtration.

2. The modified Method GS2/9‐37, as proposed by the Brazilian National Committee (and to be found in Appendix 5a of GS1 Referee Report), should be included as a separate GS1 method with proposed title: GS 1‐XX “Particle Size Distribution of Raw Sugar by Sieving (Rens Method). It should be assessed if the results of the collaborative study, already done by the Brazilian NC, are sufficient to give the method Tentative status.

3. Method GS1‐20 should be renamed as “Particle size distribution and fine grain content of raw sugar by sieving"

4. It should be investigated if alternatives for lead acetate clarification (e. g. clarification using Carrez I & II, Octapol and Claripol) can be included in Method GS 1/2/3/9‐1, Polarisation of Raw Sugar by Polarimetry.

It should be assessed if the results of the LGC SUPS proficiency test can be used to determine the precision of the alternative method(s).


Referee: Karen E. Pardoe (United Kingdom)

1. ICUMSA 32nd Session to accept the update for method GS2-33 as drafted by the GS2 Referee as a replacement for GS2/1/7/9-33 (2011) with respect to GS2.

2. GS2 Referee to remove GS1, GS7 and GS9 from the scope of GS2/1/7/9-33.

3. GS2 Referee to finalise the format for the revised GS2-33 method so that it aligns to the ICUMSA method format and can be published.

4. GS2 Referee to define and agree a list of alternative methods to GS2/1/7/9-33 to investigate, based on input from the ICUMSA 32nd session.

5. GS2 Referee to update GS2/3/9-17 to include SUPS performance data and address the concerns raised by S2 and S7 referees.

6. GS2 Referee to work cooperatively with the other Subject Referees to revise, improve and re-write the methods for determination of polarimetric sucrose content

7. GS2 Referee to include SUPS performance data in all relevant GS2 methods when they are re-written into the new method format..


GENERAL SUBJECT 3 Speciality Sugars
Referee: Andreas Georg Degenhardt (Germany)

1. According to the updated format of the ICUMSA, a method without Carrez clarification should be written down and integrated in the ICUMSA Methods Book under the status "Tentative". The suggested title is:

ICUMSA Method GS3-__ (2021): 5-Hydroxymethylfurfural (HMF) in Sugar Syrups and Invert Sugar Syrups by an HPLC Method – Tentative

An international collaborative study with low, medium and high HMF contents should be carried out and evaluated until the next ICUMSA Session.

2. Analytical methods should be assessed for applicability towards the determination of colour intensities in burnt sugar syrups and caramel syrups. The referee should give an overview with an appraisement.


Referee: José Godoy (Brazil)
Presented by Sebastiaan van Berchum (The Netherlands)

1. In order to find an alternative for lead acetate clarification in Method GS4/7-1, The Determination of Apparent Sucrose in Molasses by a Double Polarisation Method, a preparatory study should be conducted to compare the effect of using alternative clarifying agents (e. g. Carrez I & II, Octapol, Claripol) and/or NIR-polarimetry instead of lead acetate.

2. Based on the outcome of the preparatory study mentioned in Recommendation 1, the most promising alternative method should be evaluated further by conducting a collaborative study.


Referee: Camille Roussel (France)

1.The revised Method GS5-1 as outlined in Appendix 1 to this Report shall be accepted continuing its Official Status for Cane and Bagasse.

2. The new press method as drafted in Appendix 2 to this Report shall be accepted as a Tentative Method for Cane.

3. Remove the Method GS5-28 from the Methods Book.


Referee: Dierk Martin (Germany)

1. Method GS6-1 (1994) “The Determination of the Polarisation of Sugar Beet by the Macerator or Cold Aqueous Digestion Method using Lead Acetate as Clarifying Agent” shall be withdrawn.

2. Method GS6-5 (2007) – The Determination of α-Amino Nitrogen in sugar beet by the Copper Method (“Blue Number”) and method GS6-7 (2007) – The Determination of Potassium and sodium in Sugar Beet by Flame Photometry still contain the option to clarify using either lead acetate or aluminium sulphate. Both methods shall be rewritten with the restriction to aluminium sulphate only as clarification agent.

3. Developments of methods for the determination of further parameters which might be relevant for the description of sugar beet quality should be observed.


GENERAL SUBJECT 7 Cane Processing
Referee: Gillian Eggleston (USA)

1. Accept as an ICUMSA Method “Dextran in Cane Juices and Syrups by Antibody Method - Tentative” following the acceptable single laboratory validation results.

2. Accept as an ICUMSA Method “Dextran in Cane Molasses and Raw Sugars by Antibody Method - Tentative” and conduct an Inter-Laboratory analysis test.

3. Undertake validation studies with this method for sugar beet products.


GENERAL SUBJECT 8 Beet Processing
Referee: Florian Emerstorfer (Austria)

1. Further improve, collaboratively test and validate GS8-19 (2009) “The determination of dextran in beet raw juice and thick juice by a modified alcohol haze method – Tentative”.

2. Check experiences using the DASA and HPAEC methods for dextran analysis and determine whether it would make sense to develop and standardise either one or both of these methods.

3. Select, collaboratively test and validate a method for the determination of the dextran-hydrolysing activity of (commercial) dextranase products.


GENERAL SUBJECT 9 Plantation and Mill White Sugar
Referee: Vasudha Shirish Keskar (India)

1. Recommendation was postponed. To be reconsidered after finalisation of Recommendation 2.

2. A review of comparison of methods of colour analysis should be done by a group of concerned Referees and authorities of ICUMSA for establishing uniformity, including the study on use of sonication for de-aeration in four colour methods.


SUBJECT 1 Articles of Association and By-Laws
Referee: Martijn Leijdekkers (The Netherlands)

1. It is recommended to further define the objects of ICUMSA as described in Clause 3 of the Articles of Association by drafting further guidelines regarding the scope of the ICUMSA Methods Book. After adoption by the Executive Committee, this scope should be published on the ICUMSA website.

2. Clauses 4.2 and 30.1 in the Articles of Association should be adjusted in order to mention that membership fees shall be due and payable on a biennial instead of an annual basis.


SUBJECT 2 Method Format, Collaborative Testing and Statistical Treatment of Data
Referee: Hanjo Puke

1. It is recommended to amend the definitions of ICUMSA Method Status (2008) as proposed in Appendix 1 to the present Report. The flowchart for Method Status Assignment shall remain unchanged.

2. It is recommended that the Referee of Subject 6, Microbiological Methods, shall observe the further development of ISO Standard 16140 " Microbiology of the food chain – Method validation" with the aim to derive corresponding rules for ICUMSA Microbiological Methods (Appendix 2)

3. It is recommended to reactivate contact to OIML, ISO, AOAC, Codex Alimentarius, IUPAC, EDQM etc.. In 1986, there was a resolution to actively develop connections with other international organisations such as OIML, ISO, AOAC, Codex Alimentarius and IUPAC. Contact and exchange with OIML were not sufficient in recent years. OIML is today still using °S in Recommendation R14 [6], instead of °Z, introduced with the new International Sugar Scale in 1988 [7]. The extension of the wavelength range in polarimetry to near infrared (NIR) is not yet included. New contact representatives should be appointed.

4. It is recommended that ICUMSA shall contact the New York Board of Trade (NYBOT) concerning the wrong use of an outdated method for colour determination and referring it to ICUMSA. Contract 14, White Sugar Contract No. 11, ICE Futures U.S.®, Inc. SUGAR NO. 16 (Appendix 3).

5. It is recommended to publish the updated Rules and Responsibilities for ICUMSA Referees as outlined in Appendix 4 to the present Report on the ICUMSA Website.

6. It is recommended that Recommendations for "Further Studies" should indicate a plan of action.

7. It is recommended to assign Official status to Method GS1-2. Method GS1-2 was collaboratively tested in 2002, but its status is still Tentative. It must be decided, which one of Methods GS1-1 and GS1-2 shall be assigned Official (Reference) status.

The Commission agreed to give Reference Status to Method GS1-1 on a temporary basis as part of the transition phase to Methods without the use of lead acetate clarification. The final aim is to withdraw Methods using lead acetate clarification from the Methods Book.

8. It is recommended to include a disclaimer concerning the mentioning of commercial products or kits in ICUMSA Methods into the respective Methods and into the introductory part of the ICUMSA Methods Book (Appendix 5). It is recommended to replace the ICUMSA Method Templates (long and shortened) on the ICUMSA Website by two new (ninth) versions.

9. It is recommended to publish the updated list of Tentative Methods on the ICUMSA Website (Excel-Chart, Appendix 6).

10. It is recommended to publish the collection of ICUMSA Specifications as outlined in Appendix 7 on the ICUMSA Website. The draft in Appendix 7 needs further development. It is recommended to replace the ICUMSA Specifications for volumetric glassware by the corresponding ISO specifications.


SUBJECT 3 Colour, Turbidity and Reflectance Measurement
Referee: Christiane Lakenbrink (Germany)

No Recommendations


SUBJECT 4 Physical Methods
Referee: Mathis Kuchejda (Germany)

No Report; No Recommendations


SUBJECT 5 Chemical Methods
Referee: Maciej Wojtczak (Poland)

1. The method GS4/7/8/5-2 The Determination of Sucrose by Gas Chromatography in Molasses and Factory Products - Official; and Cane Juice - Tentative should be rewritten as GS4-2 Sucrose by Gas Chromatography in Molasses - Official. A separate method should be written for other factory products.

2. Further investigations of dextran analysis methods should be conducted in cooperation with GS8 and GS7 and results should be presented during the next session.

3. The Method GS2/4/8-54, Non-ionic surfactants in white sugar, molasses, and dried beet pulp, should be modified to replace the chloroform and after modification collaborative tested in cooperation with GS2, GS4, and GS8.


SUBJECT 6 Microbiological Methods
Referee: Michael Klingeberg (Germany)

1. Method GS2/3-52 (2017) “The Determination of b-glucuronidase-positive Escherichia coli and b-galactosidase-positive coliform bacteria in Sugar and Sugar Products by the Membrane Filtration Method - Accepted” The modified method, transferred into the new ICUMSA-template and adapted concerning media, should be retained with the status "Accepted".

2. Method GS2/3-53 (2017) “The Determination of Osmotolerant Yeasts and Xerophilic Moulds in Sugar Products by the Membrane Filtration Method or the Pour Plate Method - Accepted” The modified method, transferred into the new ICUMSA-template, extended by a second incubation temperature, 25 °C and 30 °C and extended by the media DG18M and De Whalley should be retained with the status "Accepted".

3. Method GS2/3-47 (2015): "The Determination of Yeasts and Moulds in Refined Sugar Products by the Pour Plate Method or the Membrane Filter Method – Official" The method was transferred into the new ICUMSA-template. Further it was extended by the media YGC, wort nutrient pads and DG18M and extended by a second incubation temperature and incubation time, 25 °C and 30 °C for at least 5 to 7 days. The method status should be changed to “Accepted”.

4. The terms (sugar, sugar products, dark syrup, refined sugar products) in the texts of all microbiological methods shall be defined as soon as possible in accordance with the definitions of ICUMSA in general.


SUBJECT 7 Sampling, Sample Handling and Sample Preparation
Referee: Alan N. Mead (United Kingdom)

1. The recommended procedures for sampling of the various categories of material should be under General Subject heading(s) in a similar manner to those for the sampling for microbiological analyses.

2. On acceptance of Recommendation 1, the following new method should be included into the ICUMSA Methods Book: Method GS1/2/3/9 - XX (2021) Sampling, Sample Handling and Sample Preparation of all Free-Flowing Sugars for Analyses other than Microbiological.

3. Also on acceptance of Recommendation 1, the following new method should be included into the ICUMSA Methods Book: Method GS3/4 - XX (2021) Sampling, Sample Handling and Sample Preparation of Liquid Sugar Products, Syrups and Molasses for Analyses other than Microbiological.