25th ICUMSA Session 2006

Final Recommendations

GS1: Raw Sugar (Referee: Dr. Les A. Edye, Australia)

No Recommendations

GS2: White Sugar (Referee: Geoff Parkin, UK)

1. Method GS2/3-19, The Determination of Insoluble Matter in White Sugar by Membrane Filtration should be rewritten to incorporate the modifications tested in the collaborative study and should be Officially adopted for all levels of insoluble matter.

2. ICUMSA Draft Method No.7 (2006), The Determination of Arsenic, Cadmium, Copper and Iron in White Sugar by Atomic Absorption Spectroscopy should be collaboratively tested without delay. If the results of this study prove satisfactory then it should also be Officially adopted.

3. Every assistance should be given to the Referee for Subject 3 and the ISBT in validating their proposed method for the Determination of Turbidity in White Sugar.

This work has been done and will be reported during the S7 presentation.

4. The status of Method GS2/3-40 Part B, The ICUMSA 24 Hour Acid Beverage Floc Test for Beet White Sugar should be changed to Accepted. A rapid test for Acid Beverage Floc in Cane White Sugar is still required.

5. Method GS2/3-35, the second part: The Determination of Sulphite in Brown Sugars by an Enzymatic Method, should be collaboratively tested in conjunction with the Referee for GS3.

GS3: Specialty Sugars (Referee: Gloria Negbenebor, UK)

1. To develop an alternate method for determination of Starch (anti-caking agent) in Icing Sugar based on a Starch-Iodine reaction. To obtain shorter time for analysis compared with the time required for filtration and drying in Method GS3-21.

2. Progress a collaborative trial to demonstrate the precision of Method GS4-13 Determination of Refractometric Dry Substance of Molasses, for liquid sucrose solutions. With the view of proving and writing up the method for the GS3 Subject group.

3. Following from a preliminary work done on Sulphite in Raw Sugars by Mr Maurice Daruty, Associate Referee for GS1 & GS3. I would like to recommend a collaborative trial for determination of sulphite in Direct Consumption Raw Sugars in conjunction with GS1 Referee.

GS4: Molasses (Referee: Dr. Gillian Eggleston, USA)

1. Confirm (ratify) the Official Status of GS4/3-3 “The Determination of Total Reducing Sugars in Cane Molasses and Refined Syrups by the Lane & Eynon Constant Volume Procedure”. Adopt the precision indicators obtained in the 2002 Collaborative Test, namely repeatability (r) 0.77 and reproducibility (R), 1.60. (Mean Horwitz Ratio, 1.50).

2. Confirm (ratify) the Official Status of GS4/3-7 “The Determination of Total Reducing Sugars in Molasses and Refined Syrups after Hydrolysis by the Lane & Eynon Constant Volume Procedure” for both cane and beet molasses. Adopt the precision indicators obtained in the 2002 Collaborative Test, namely repeatability (r) 1.51 and reproducibility (R), 2.47. (Mean Horwitz Ratio, 0.77).

3. Continue research studies on Draft Status Method “Determination of Apparent Total Sucrose from Sucrose, Glucose and Fructose in Molasses by an Enzymatic Method” (No Status). Review the text of the method in light of the results of the research study presented at ICUMSA 2006 Brazil session by Gillian Eggleston and M. Füsün Kavas, and comments of the participants. Improve the stability and shelf-life of the enzymes.

4. Continue to establish a method for the determination of mineral hydrocarbons in molasses.

GS5: Cane (Referee: Ashok Sitaram Patil, India)

1. To investigate and standardise the technology to find out polyphenols and amino acids in cane juice using GC-MS technology.

GS6: Beet (Referee: Dr. Dierk Martin, Germany)

1. Draft Method No. 5 (2005) “Determination of Potassium and Sodium in Sugar Beet by Flame Photometry” should be given Official status and be numbered GS6-7 (2006).

2. Draft Method No. 6 (2005) “Determination of alpha-Amino Nitrogen in Sugar Beet by the Copper Method (‘Blue Number’)” led to acceptable precision data in the collaborative study for the aluminium salt defecation and should therefore be given Official status. It should be numbered GS6-5 (2006).

3. Further collaborative studies for the determination of potassium, sodium and alpha-amino-nitrogen should be conducted in order to collect more precision data under improved conditions.

GS7: Cane Sugar Processing (Referee: M.B. Londhe, India)

1. The method “Use of non-lead clarificants for high-grade products clarification with NIR polarimeter proposed by Réunion” (Appendix 1) is to be accepted as Draft Method and collaboratively tested for syrups, intermediate molasses and high-grade massecuites.

2. The method proposed by Brazil for replacement of lead clarificants by aluminum chloride and calcium hydroxide is to be accepted as a Draft method for analysis of high grade products of cane sugar process streams.

3. For determination of MA & CV in massecuite samples, further method validation study of the VSI & CERF methods is recommended.

4. Use of gamma ray irradiation technique for preservation of cane sugar processing products during international inter laboratory/ collaborative tests shall be explored, and if appropriate, be written as standard specification with Official status.

5. It is recommended to extend the scope of Method GS7-21 for syrup and clarified syrup for determination of turbidity – Accepted status as proposed in Appendix 6 (amended).

GS8: Beet Sugar Processing (Referee: Jean-Pierre Lescure, France)

1. The ICUMSA Draft Method No. 1 (2005) “The Determination of Mannitol in Beet Brei by HPAEC” should be further studied and evaluated.<//font>

2. The ICUMSA Method GS1-15 (2005) “The Determination of Dextran in Raw Sugar by a Modified Alcohol Haze Method – Official” should be modified and renamed: GS1/2/8-15 “The Determination of Dextran in Sugars and Juices by a Modified Alcohol Haze Method – Official for Raw Sugars – Accepted for Beet Sugar Processing”.

3. Draft Method No. 3 (2005) should be revised to include beet juice analysis.

4. The Eggleston and FERMENTEC Enzymatic method should be further studied in order to adapt it for the needs of beet sugar processing.

GS9: Plantation White Sugar (Referee: Dr. Vasudha Shirish Keskar, India)

1. The Method numbers, Scope and Field of Application of the following methods should be changed to accommodate Plantation White Sugar:

Method GS1/2/3-1 (1994), Method GS1/2/3/4/7/8-23 (1994), Method GS 2-6 (2001), Method GS2/1/3-15 (2002), Method GS2/3-19 (2002), Method GS2/3-25 (1994), Method GS 2/3-5 (2001), GS 2-37 (1994).

2. Studies should be conducted to modify the following methods with respect to sample preparation taking into consideration the requirements of Plantation White Sugar:

Method GS2/1/3-27, Method GS2/3-29, Method GS2/3/7/8-31.

3. After modification Method GS 2/3/7/8-31 should be collaboratively tested on Plantation White Sugar.

4. Method GS 2/1/7-33 should be collaboratively tested on Plantation White Sugar at levels approaching 70 mg/kg.

5. The Referees for GS2, GS3 and GS9 should be contacted in order to review the need for Method GS2/3-9 in the Methods Book. Efforts will be made to replace Method GS2/3-9 by Official Method GS9/1/2/3-8. The decision will be finalised in the next Session.

S1: Constitution and By-Laws (Referee: Prof. Giuseppe Vaccari, Italy)

1. The revised text of the point 1 of the Article 1 of By-Laws, as specified in the Report, should be submitted to a postal ballot.

S2: Oligosaccharides and Polysaccharides (Referee: Dr. Klaus Thielecke, Germany)

1. The modified haze method for the determination of dextran in cane white sugar and plantation white sugar (Appendix 1) should be adopted Officially. The provisional precision data under paragraph 8.2 of the method should be updated with the data of the ANOVA Table in Appendix 2 (Table 6).

2. The VSI Haze Method for the determination of dextran in sugar cane juice and sugar house products (Appendix 3) should be studied further.

3. The draft methods for the determination of mannitol (No. 1), beta-fructosides (No. 2) and starch (No. 3 and 4) in the ICUMSA Methods Book should be studied further with the aim of giving them a final status.

4. The Midland monoclonal antibody method and the enzymatic mannitol method of Eggleston et al. should be tested in Subject 2.

S3: Method Format, Collaborative Testing and Statistical Treatment of Data (Referee: Mary An Godshall, USA)

1. Original Recommendations 1, 2, 3, 4, 5 and 6 are referred to the Strategic Planning Committee.

2. Extend Method GS4-13 (The Determination of Refractometric Dry Substance (RDS%) of Molasses – Accepted) to include Liquid Sugar.

3. Include Liquid Sugar in Subject GS3, Specialty Sugars.

S4: Density, Optical Rotation and Refractive Index (Referee: Mathis Kuchejda, Germany)

1. The Recommendation is to replace the presently published value of alpha = 14.9276° for a 100 °Z solution at 880 nm by the value of alpha = 14.927°.

S5: Dry Substance (Referee: Prof. S.K. Gupta, India)

The Report was not presented, no Recommendations were made.

S6: Indirect Methods of Analysis (Referee: Dr. Les A. Edye, Australia)

1. It is recommended that a working group be formed to develop a protocol for validating indirect methods of analysis (and other methods not suited to the collaborative testing protocol) and that this protocol be based on the principles of quality auditing.

S7: Colour, Turbidity and Reflectance Measurement (Referee: Dr. Christiane Lakenbrink, Germany)

1. It is recommended to carry out a collaborative study with the aim of establishing an alternative for the Braunschweig colour-type standards for ICUMSA Method GS2-13 (1998). For the alternative material (glass frits and/or ceramic tiles) a reproducible production has to be ensured and the calibration by a certified institution has to be defined.

2. Recommend Official status for Turbidity in White Sugar.

3. Create a separate method for Turbidity in White Sugar that references Method GS2/3-10 for procedure.

S8/9: Chromatographic Techniques

No Referee, no Report, no Recommendations.

S10: Enzymatic and Immunological Methods

No Referee, no Report, no Recommendations.

S12: Microbiolgy (Referee: Dr. Maritta Jacobs, Germany)

1. It is recommended to test the DG-18S and MEA40 media in comparison with the Wort 50 agar for the recovery of “wild osmotolerant yeasts” in contaminated sugar samples. 

S13: Reducing Sugars (Referee: Merih Füsün Kavas, Turkey)

1. Adoption of the precision indicators obtained in the collaborative test reported for Reducing Sugars in cane molasses by Method GS4/3-3, namely repeatability (r), 0.77 and reproducibility (R), 1.60.

2. Note the collaborative test reported for Total Reducing Sugars after Hydrolysis by Method GS4/3-7, namely repeatability (r), 1.51 and reproducibility (R), 2.47.

3. Continue collaborative evaluation of the remaining copper reduction methods in cane and beet molasses, namely GS4/3-7 for beet molasses, GS4/3-9 and GS4-5.

4. Carry out a collaborative study on the new enzymatic Method GS4-6 (2004). In accordance with Recommendation 1 of Subject 2 at the 2004 Session, this Method can no longer be so designated as a No-status method. Therefore it should now be designated as Draft method No. 8 (2006).

S14: Ash (Referee: Dr. Jean-Pierre Ducatillon, France)

1. Ash method GS 2/3-17 should be collaboratively tested for plantation white sugar in order to determine reproducibility.

2. The conductivity value of 0.0005 mol/L potassium chloride solution should be determined.