Final Recommendations
GS1 Raw Sugar
(Andrew Harrison, Australia)
1. The current wording in Method GS1/2/9-15 (2007) Section 6.1 be changed from “… with matched 5 cm cells.” to “… with matched cells. The cell length selected may be 2 cm or 5 cm as available.”
2. The current wording in Method GS1/2/9-15 Section 7.1, dot point 6, be changed from “…pair of matched 5 cm cells…” to “…pair of matched cells…”
3. The current wording in Method GS1/2/9-15 Section 7.3, dot point 8, be changed from “Determine the cell correction at 720 nm using a pair of matched 2 cm cells for raw sugar against distilled water or a pair of matched 5 cm cells for white and plantation white sugars against distilled water.” to “Determine the cell correction at 720 nm against distilled water using a pair of matched cells the same size as used to establish the standard graph.”
4. Insoluble Solids Method. An investigation be undertaken to:
(a) determine to what particle size the measurement of insoluble solids in raw sugar is practical and appropriate, and
(b) determine a suitable method for the measurement of Insoluble Solids in Raw Sugar for subsequent collaborative testing.
GS2 White Sugar
(Karen Pardoe, UK)
1. GS2 Referee to update method GS2/1/7/9-33, ‘The Determination of Sulphite by the Rosaniline Colorimetric Method’, with respect to the requirement for the reagents sulphite-free sugar and sodium sulphite heptahydrate, based on information obtained from Associate Referees and ICUMSA members present at the 29th session.
2. GS2 Referee to compare results obtained for the determination of polarisation of white sugar for the method(s) as currently written and for the gravimetric preparation method (as proposed by the Subject 4 Referee). The results may be obtained through collaborative testing organised by the GS2 Referee or through the use of the available sugar proficiency testing scheme (SUPS).
3. Adoption of the method proposed as ‘Method for the Determination of Specified Heavy Metals in White Sugar’. (Appendix 2 of this report)
4. Once the document from Recommendation 3 is approved for use, the GS2 Referee will recommend a change in SUPS to reflect the new method. This will then mean the current SUPS metal contaminants sample is suitable for assurance/validation of laboratories testing white sugar according to the guidelines prescribed in the new method. (Recommendation 2 from 2012)
5. GS2 Referee to obtain information from Associate Referees and ICUMSA members present at the 29th session about other possible metals of interest with respect to expanding the scope of the method proposed in Recommendation 3. If sufficient information and interest is provided, a collaborative study will be set up in order to validate any new metals.
6. Gain confirmation of supply of ABF positive beet and cane sugar in order to collaboratively test the methods proposed by J Jensen (Nordic Sugar) and M McKee (SPRI) alongside the current ICUMSA methods for Acid Beverage Floc (GS2/3-40 Parts A and B). (Recommendation 4 from 2012)
7. GS2 Referee to define an appropriate validation study to provide precision data for GS2/1/3/9-15, ‘The Determination of Sugar Moisture by Loss on Drying’, based on information obtained from Associate Referees and ICUMSA members present at the 29th session.
GS3 Specialty Sugars
(Andreas Georg Degenhardt, Germany)
1. The Optimized Monier-Williams Method combined with Titration as well as Ion Chromatography should be checked for application for the determination of total Sulphite/SO2 content in Brown Sugar. If the method is applicable, a collaborative study for validation should be organized in 2014/15 in cooperation with General Subject 1.
2. The HPLC method should be assessed for applicability towards the determination of HMF content in Invert Sugar Syrups. A collaborative study inside of German National Committee of ICUMSA should be done in 2014/15.
GS4 Molasses
(Nigel Jones, UK)
1. Establish if the Carrez reagents can be used as a replacement for Lead Acetate for beet and/or cane molasses in method GS4/7-1 using a standard polarimeter (587 nm or 589.5 nm). As discussed in the previous sections, the biggest issue at the moment is the colour of the molasses solutions as results obtained from the two methods are comparable. Investigations into the use of other decolourising agents such as activated carbon could be used to overcome this issue although these also may remove some optically active components which would change to composition of the solution being tested even further.
2. Investigate the potential of using NIR polarimetry without a clarification step for beet and/or cane molasses as a replacement for lead sub-acetate in GS4/7-1. As NIR is less sensitive to the colour of the solutions this may a good alternative to the use of lead sub-acetate as a clarification step. However, quite a lot of work has already been undertaken in this area and some of the issues that need to be further investigated are as follows;
Undertake trials on molasses samples using both the NIR and lead methods so a comparison of the methods can be undertaken. It will also be good to test a number of different origins to see if the actual composition of the molasses effects the variation between the two methods.
Check filtration times for both beet and cane molasses – determine if leaving a sample of a period of time will change the pol value of the sample significantly.
Establish whether the method is suitable for both beet and cane molasses.
3. Investigate the potential of using NIR polarimetry with a clarification step for beet and/or cane molasses in method GS4/7-1. Work has already been undertaken in this area and the Carrez reagents have been shown to correlate well with lead sub-acetate. Further work includes developing the method for both beet and cane molasses.
GS5 Cane
(Camille Roussel, Reunion, France)
1. A new method should be created: “The Determination of Apparent Sugar Content by Polarisation, Soluble Solids Content by Refractometry and Fibre Content (calculated) in Cane and Bagasse using Wet Disintegration to obtain an Extract, Pressure Filtration and Near Infra-Red Polarimetry” – Tentative
2. A new method should be created: “The Determination of Apparent Sugar Content by Polarisation, Soluble Solids Content by Refractometry and Fibre Content (calculated) in Cane using a Press to obtain Cane Juice according to Berding and Pollock, Pressure Filtration and Near Infra-Red Polarimetry” – Tentative
3. As the methods proposed in recommendations 1 and 2 are similar to methods GS5/7-1 and to GS5/7-29, a collaborative study should be undertaken to assess if the two tentative methods meet the criteria for “Official” methods and how will they compare and perform overall. The precision data obtained can then be evaluated in order to suggest which of these methods is technically superior. In order to simplify the collaborative study, it is suggest to remove the “Holden” method suggested in the previous report, as it time consuming and not in general use.
4. Regarding GS5/7-1 and GS5/7-29, polarimeter wavelength is not specified. With the development of NIR polarimetry confusion may occur. It is suggested to specify the polarimeter wavelength for GS1/7-1 and GS5/7-29 : 587 or 589.5 nm
5. GS7-3 and GS7-5 are also used for cane analysis and should therefore be re-numbered respectively GS 7/5-3 and GS 7/5-5.
GS6 Beet
(Dierk Martin, Germany)
The enzymatic determination of invert sugar in sugar beets shall be described in the ICUMSA method format. It should include the automated procedure as well as the manual analysis.
In order to gain Official status for the method a ring test should be conducted.
Developments of methods for the determination of further parameters which might be relevant for the description of sugar beet quality should be observed.
GS7 Cane Sugar Processing
(Gillian Eggleston, USA)
1. The new ICUMSA Method GS7-33 (2013) “Determination of the Relative Activity of Commercial Amylase as used in Sugar Cane Processing and Refining – Tentative,” should be given the status Official.
2. Collaborative trials should be undertaken on the GS7-31 (2011) Method: “The Determination of Pol by NIR Polarimetry and Brix for Sugarcane and Factory Product – Tentative.”
3. A new method should be created: “The Determination of Apparent Sugar Content by Polarisation, Soluble Solids Content by Refractometry and Fibre Content (calculated) in Cane using a Press to obtain Cane Juice according to Berding and Pollock, Pressure Filtration and Near Infra-Red Polarimetry” – Tentative.
4. Collaborative trials should be undertaken on Official ICUMSA GS5/7-1 (2011) Method and the new method “The Determination of Apparent Sugar Content by Polarisation, Soluble Solids Content by Refractometry and Fibre Content (calculated) in Cane using a Press to obtain Cane Juice according to Berding and Pollock, Pressure Filtration and Near Infra-Red Polarimetry” – Tentative.
GS8 Beet Sugar Processing
(Jan Maarten de Bruijn, Germany)
1. Develop and evaluate a simple and rapid method to indicate the presence (i.e. approximate content) of dextran in sugar beet and/or raw juice
2. Develop and evaluate the determination of dextranase activity by a simple (titration) method
GS9 Plantation and Mill White Sugar
(Vasudha Shirish Keskar, India)
1. Based on the results of collaborative study the method The Determination of Zinc and Cadmium in Plantation White Sugar by Flame Atomic Absorption Spectroscopy should be given official status. During editing of the Proceedings this was changed to Tentative Status.
2. Necessary changes should be made in method GS9/1/2/3-8 (2005) The Determination of Sugar Solution Colour at pH 7.0 by the MOPS Buffer Method as per requirement of low colour PWS and White Sugar.
S1 Constitution and By-Laws
(Geoff Parkin, UK)
1. In accordance with the wishes of the members, the Officers of ICUMSA will progress the change of status of ICUMSA to that of a Company Limited by Guarantee (ICUMSA Ltd) and registered in the UK. The Articles of Association shall reflect the normal procedures adopted by ICUMSA whilst complying with Company Law in the UK. Expert external advice shall be sought where necessary. Once drawn up the Articles will be subject to agreement by National Committees.
2. A new category of membership shall be introduced when creating the new Articles allowing for individuals who work in the field of sugar analysis/processing, in a country not having a registered National Committee, to become members. The concerns expressed by some National Committees will be borne in mind and the wording will be subject to agreement by existing National Committees.
S2 Method Format, Collaborative Testing and Statistical Treatment of Data
(Roger Wood, UK)
1. To ask and encourage members of ICUMSA Subject 2 to develop and refine the Report “Information to and Procedures for ICUMSA Working Groups to Consider when Specific Methods are Being Developed and Adopted by ICUMSA”.
S3 Colour, Turbidity and Reflectance Measurement
(Christiane Lakenbrink, Germany)
No recommendations
S4 Density, Optical Rotation and Refractive Index
(Mathis Kuchejda, Germany)
It is recommended to add a gravimetric method as described below to SPS-1 for the preparation of “normal sugar solutions”. For the preparation of test solutions for Method GS2/3-1 comparative tests between the volumetric and the gravimetric method as proposed by the Referee of GS2 should be performed. The volumetric method should be maintained as an alternative preparation method in the above mentioned methods.
2. It is recommended to add to SPS 1, 7.5: “The quartz plate in its final mount has to be checked by the manufacturer regarding its azimuthal rotation. The result has to be documented in the correspondent factory certificate. With each recalibration the azimuthal rotation has to be rechecked and documented again.”
S5 Chemical Method
(Maciej Woitczak, Poland)
1. The Tentative status of chemical methods should be kept and they should be validate as soon as possible in the areas in which their validation has not been performed.
2. The present enzymatic and chromatographic methods; particular with Accepted status should be verified/unified. New methods should be developed in cooperation with General Subjects.
3. ICUMSA should cooperate with CEN for development for suitable method for nitrite determination in sugar by-products. ICUMSA members should participate in the coming studies to be organized under the CEN mandate.
S6 Microbiology
(Maritta Jacobs, Germany)
No Final Recommendations
S7 Indirect Methods of Analysis and New Technologies
(Amélia Andrade Ferraz, Denmark)
1. Indirect methods of analysis validated in accordance with the general guidelines proposed, that comply with the requirements for the method performance characteristics, should be given “Accepted Status”.
2. The proposed general guidelines should be reviewed in collaboration with the referee and associate referees of S2 Method Format, Collaborative Testing and Statistical Treatment of Data, to be in accordance with the requirements of the ICUMSA Methods Format.
3. General guidelines for the validation of indirect methods of analyses that do not fulfil the requirements of the general guidelines proposed in this report, but serve a useful function in the industry and trade and have a long practice of successful use, should be defined.
S8 Sampling and Sample Preparation
(Roger Wood, UK)
1. To ask and encourage members of ICUMSA Subject 8 to develop and refine the IAM paper on “SAMPLING IN CODEX STANDARDS – HOW IT SHOULD BE TREATED” for ICUMSA purposes, and to extend the paper by considering the different techniques of sampling which may be used within the sugar sector.