A New JECFA Method for GC-MS Determination of Propylene Chlorohydrine Residues in Hydroxypropylated Starches.

BACKGROUND: Propylene chlorohydrins (PCHs) are formed as byproducts in the reaction between starch and propylene oxide (PO). For hydroxypropylated (HP) starch applications in food, Joint FAO/WHO Expert Committee on Food additives (JECFA) set the maximum allowed total propylene chlorohydrin (PHC-t) residues level at 1 mg/kg. OBJECTIVE: To develop an improved analytical method for the determination of the PCH-t content in starches in the low mg/kg range to replace the outdated JECFA method. METHODS: A new GC-MS method that utilizes aqueous methanol as extraction medium for PCH. The GC-MS system is equipped with a programmable temperature vaporization injector and Stabilwax-DA column and uses helium as carrier gas. Quantitative detection is achieved in selected ion monitoring mode. RESULTS: This single-laboratory validation (SLV) study showed good linear calibrations for both 1-chloro-2-propanol (PCH-1) and 2-chloro-1-propanol (PCH-2) in the concentration range of 0.5-4 mg/kg in dry starch. The lower LOQ of PCH-1 and PCH-2 was 0.2-0.3 mg/kg in dry starch, the reproducibility RSD (RSDR) at the concentration level of 1-2 mg/kg in dry starch was 3-5%, and the recovery values for both PCH-1 and PCH-2 were in the range of 78-112% at a concentration level of about 0.6 mg/kg in dry starch. Compared with the current, outdated JECFA method, the new GC-MS method is more sustainable, less laborious, and therefore more economical. The analytical capacity of the new method is 4-5 times higher than the analytical capacity of the old JECFA method. CONCLUSION: The GC-MS method is fit for a multi-laboratory trial (MLT). HIGHLIGHTS: Based on the results of this SLV and the MLT (will be published in a second paper), the Joint FAO/WHO Expert Committee on Food Additives has recently decided to replace the outdated GC-FID JECFA method with the new GC-MS method for the determination of PCH-t content in starches.

The Challenge of Measuring Sweet Taste in Food Ingredients and Products for Regulatory Compliance: A Scientific Opinion.

The Codex Alimentarius Commission, a central part of the joint Food and Agricultural Organization/World Health Organizations Food Standards Program, adopts internationally recognized standards, guidelines, and code of practices that help ensure safety, quality, and fairness of food trade globally. Although Codex standards are not regulations per se, regulatory authorities around the world may benchmark against these standards or introduce them into regulations within their countries. Recently, the Codex Committee on Nutrition and Foods for Special Dietary Uses (CCNFSDU) initiated a draft revision to the Codex standard for follow-up formula (FUF), a drink/product (with added nutrients) for young children, to include requirements for limiting or measuring the amount of sweet taste contributed by carbohydrates in a product. Stakeholders from multiple food and beverage manufacturers expressed concern about the subjectivity of sweetness and challenges with objective measurement for verifying regulatory compliance. It is a requirement that Codex standards include a reference to a suitable method of analysis for verifying compliance with the standard. In response, AOAC INTERNATIONAL formed the Ad Hoc Expert Panel on Sweetness in November 2020 to review human perception of sweet taste, assess the landscape of internationally recognized analytical and sensory methods for measuring sweet taste in food ingredients and products, deliver recommendations to Codex regarding verification of sweet taste requirements for FUF, and develop a scientific opinion on measuring sweet taste in food and beverage products beyond FUF. Findings showed an abundance of official analytical methods for determining quantities of carbohydrates and other sweet-tasting molecules in food products and beverages, but no analytical methods capable of determining sweet taste. Furthermore, sweet taste can be determined by standard sensory analysis methods. However, it is impossible to define a sensory intensity reference value for sweetness, making them unfit to verify regulatory compliance for the purpose of international food trade. Based on these findings and recommendations, the Codex Committee on Methods of Analysis and Sampling agreed during its 41st session in May 2021 to inform CCNFSDU that there are no known validated methods to measure sweetness of carbohydrate sources; therefore, no way to determine compliance for such a requirement for FUF.

Results Multi-Laboratory Trial ISO/CD 22184-IDF/WD 244: Milk and Milk Products-Determination of the Sugar Contents-High-Performance Anion Exchange Chromatography Method with Pulsed Amperometric Detection.

BACKGROUND: In this international Multi-Laboratory Trial (MLT) the precision data and the accuracy of the ISO/CD 22184 IDF/WD 244 analytical method for the quantification of 6 different mono- and disaccharides (galactose, glucose, fructose, sucrose, lactose, and maltose) in milk and milk products with high-performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) are established. OBJECTIVE: Thirteen different laboratories participated (located in New Zealand, the United States, and Europe). The study was divided into two parts. First, the learning/familiarization part in which the participants got experienced with the method. After successfully completing this part, the participants were allowed to continue with the second part of this trial: the analyses of the seven blind MLT duplicate samples. METHOD: The selected seven MLT samples comprise five MUVA reference dairy samples, one NIST-certified infant formula and one industrial sample. In the Tables S-1 to S-6 the results of this MLT study have been summarized per sugar. There is a very good agreement between the MUVA and NIST-certified sugar contents in the MLT samples and in the MLT established sugar contents in those MUVA and NIST samples. RESULTS: This demonstrates that the accuracy of the newly developed HPAEC-PAD method is very good. CONCLUSIONS: Certificates of analysis were available for both the MUVA samples and the NIST sample. There is a very good agreement between the by MUVA- and NIS-certified sugar contents in the MLT samples and the corresponding in the MLT established sugar contents. This demonstrates that the accuracy of the HPAEC-PAD method is very good. In the IDF/ISO Analytical Week in June 2019 in Prague the report on the MLT study were discussed and adopted.

Determination of Fructans in Infant Formula and Adult/Pediatric Nutritional Formula by Anion-Exchange Chromatography with Pulsed Amperometric Detection after Enzymatic Treatment: Collaborative Study, Final Action 2016.14.

BACKGROUND: Fructans are added to infant formula and adult nutritionals for their prebiotic effect. A method (AOAC 2016.14) was developed for their analysis which has already demonstrated excellent performance during single laboratory validation. OBJECTIVE: To determine repeatability and reproducibility of the method through a collaborative study. METHODS: Fourteen laboratories from 11 different countries enrolled for the study. Participants analyzed a practice sample, then 8 formula or adult nutritionals in blind duplicate. Results and any method modifications were reported to the study director. RESULTS: Twelve laboratories provided results on time for reporting. Precision results for five samples met the requirements of the Standard Method Performance Requirements (SMPR 2014.002), with RSDr ranging from 3.60 to 4.25% and RSDR ranging from 5.90 to 11.7%. The practice sample also met the requirements of SMPR 2014.002, with RSDr and RSDR of 2.53% and 6.70% respectively. Precision results for three test samples did not fully meet the SMPR, with RSDr ranging from 2.27 to 7.65% and RSDR ranging from 12.8 to 15.1%. After review, the AOAC Stakeholder Panel for Infant Formula and Adult Nutritional Expert Review Panel (SPIFAN ERP) concluded that the data presented mostly met the SMPR and hence recommended that the method to be advanced for adoption as an AOAC Final Action method. CONCLUSIONS: The method described in AOAC 2016.14 is suitable for the determination of fructans in infant formula and adult nutritionals.

Results Multi-Laboratory Trial ISO/CD 22184 - IDF/WD 244: Milk and milk products - Determination of the sugar contents - High performance anion exchange chromatography method with pulsed amperometric detection (HPAEC-PAD).

BACKGROUND: In this international Multi Laboratory Trial (MLT) the precision data and the accuracy of the ISO/CD 22184 IDF/WD 244 analytical method for the quantification of 6 different mono- and disaccharides (galactose, glucose, fructose, sucrose, lactose and maltose) in milk and milk products with high performance anion exchange chromatography with pulsed amperometric detection (HPAEC-PAD) are established. OBJECTIVE: Thirteen different laboratories participated (located in New Zealand, United States, Europe). The study was divided into two parts. Firstly, the learning/familiarization part in which the participants got experienced with the method. After successfully completing this part, the participants were allowed to continue with the second part of this trial: the analyses of the seven blind MLT duplicate samples. METHOD: The selected seven MLT samples comprise five MUVA reference dairy samples, one NIST certified infant formula and one industrial sample. In the Tables S-1 to S-6 the results of this MLT study have been summarized per sugar. There is a very good agreement between the MUVA and NIST certified sugar contents in the MLT samples and the in the MLT established sugar contents in those MUVA and NIST samples. RESULTS: This demonstrates that the accuracy of the newly developed HPAEC-PAD method is very good. CONCLUSIONS: Certificates of analysis were available for both the MUVA samples and the NIST sample. There is a very good agreement between the by MUVA and NIS certified sugar contents in the MLT samples and the corresponding in the MLT established sugar contents. This demonstrates that the accuracy of the HPAEC-PAD method is very good.In the IDF/ISO Analytical Week in June 2019 in Prague the report on the MLT study were discussed and adopted.

The Determination of Sugars in Dairy Products: Development of a New Standard Method for the International Dairy Federation and the Internal Organization for Standardization.

A method using high-performance anion-exchange chromatography (HPAEC) with a pulsed amperometric detector (PAD) for the determination of mono- and disaccharides is described. The method was accepted by the International Dairy Federation and the Internal Organization for Standardization as a new work item for the determination of sugars in dairy matrixes, and the Milk and Milk Products technical committee of ISO/TC 34/SC 5 accepted the topic "Milk and milk products - Determination of the sugar contents - High-performance anion-exchange chromatographic method (HPAEC-PAD)" as a new work item. The proposed method consists of an aqueous ethanol extraction of the sugars in the dairy sample, followed by clarification with Carrez I and II reagents. The clarified filtrate is diluted and then directly introduced in the HPAEC-PAD system for quantification of the sugars. A single-laboratory validation of the proposed method has been scheduled for spring 2017.

Dual-Laboratory Validation of a Method for the Determination of Fructans in Infant Formula and Adult Nutritionals: First Action 2016.14.

Until recently, only two AOAC Official MethodsSM have been available for the analysis of fructans: Method 997.08 and Method 999.03. Both are based on the analysis of the fructan component monosaccharides (glucose and fructose) after hydrolysis. The two methods have some limitations due to the strategies used for removing background interferences (such as from sucrose, α-glucooligosaccharides, and free sugars). The method described in this paper has been developed to overcome those limitations. The method is largely based on Method 999.03 and uses combined enzymatic and SPE steps to remove the interfering components without impacting the final analytical result. The method has been validated in two laboratories on infant formula and adult nutritionals. Recoveries were in the range of 86-119%, with most being in the range of 91-104%. RSDr values were in the range of 0.7-2.6%, with one exception when the fructan concentration was close to the LOQ, resulting in an RSDr of 8.9%. The performance is generally within the requirements outlined in the AOAC Standard Method Performance Requirements (SMPR® 2014.002), which specifies recoveries in the range of 90-110% and RSDr values below 6%.

Strategy to identify and quantify polysaccharide gums in gelled food concentrates.

A strategy for the unambiguous identification and selective quantification of xanthan gum and locust bean gum (LBG) in gelled food concentrates is presented. DNA detection by polymerase chain reaction (PCR) showed to be a fast, sensitive, and selective method that can be used as a first screening tool in intact gelled food concentrates. An efficient isolation procedure is described removing components that may interfere with subsequent analyses. NMR spectroscopy enabled the direct identification of xanthan gum and the discrimination between different galactomannans in the isolated polysaccharide fraction. An enzymatic fingerprinting method using endo-ß-mannanase, in addition to being used to differentiate between galactomannans, was developed into a selective, quantitative method for LBG, whereas monosaccharide analysis was used to quantify xanthan gum. Recoveries for xanthan gum and LBG were 87% and 70%, respectively, with in-between day relative standard deviations below 20% for xanthan gum and below 10% for LBG.

Dietary fibre: challenges in production and use of food composition data.

Dietary fibre is a heterogeneous group of components for which several definitions and analytical methods were developed over the past decades, causing confusion among users and producers of dietary fibre data in food composition databases. An overview is given of current definitions and analytical methods. Some of the issues related to maintaining dietary fibre values in food composition databases are discussed. Newly developed AOAC methods (2009.01 or modifications) yield higher dietary fibre values, due to the inclusion of low molecular weight dietary fibre and resistant starch. For food composition databases procedures need to be developed to combine 'classic' and 'new' dietary fibre values since re-analysing all foods on short notice is impossible due to financial restrictions. Standardised value documentation procedures are important to evaluate dietary fibre values from several sources before exchanging and using the data, e.g. for dietary intake research.