Measurement of Gluten in Food Products: Proficiency‐Testing Rounds as a Measure of Precision and Applicability

In 2008, Codex Alimentarius endorsed the R5 Enzyme‐Linked Immunosorbent Assay (ELISA) method as Method Type 1 for gluten measurement in gluten‐free foods. The most recognized R5 ELISA test kit is the RIDASCREEEN® Gliadin (R7001; manufacturer R‐Biopharm). Beside collaborative tests that led to several international approved methods of this test kit, proficiency‐testing (PT) rounds are regularly performed in Europe by different PT providers. Results from these rounds were analyzed regarding the number of participating labs with acceptable results for the RIDASCREEN® Gliadin. All PT rounds document the excellent consistency and comparability of results. The data show that the RIDASCREEN® Gliadin R5 ELISA is also applicable to cake mix, oat‐based foodstuff, infant soya formula, cookies, canned boiled sausage, gravy thickener, pasta, and potato dumpling. These rounds also included the analysis of blank matrices. It was found that more than 95% of all participating laboratories correctly detected these samples as negative. Other gluten test kit manufacturers were analyzed as well, but due to the low number of participants using these test kits results were often only analyzed in a qualitative manner questioning the comparability of these kits to the RIDASCREEN® Gliadin R5 ELISA

Determination of Gliadin as a Measure of Gluten in Food by R5 Sandwich ELISA RIDASCREEN® Gliadin Matrix Extension: Collaborative Study 2012.01

Background According to Codex Alimentarius, food products containing less than 20 mg/kg gluten can be labeled as “gluten-free.” Since 2002, the R5 antibody method allowed determination of gluten levels and led to a huge improvement of products available to celiac disease (CD) patients. Method The R5-containing test kit RIDASCREEN® Gliadin in combination with the cocktail solution was endorsed as Codex Type 1 Method in 2006 based on a collaborative study with corn-based bread, rice-based dough, wheat starches, rice, and corn flour. In 2012, the method was approved as First Action Official Method$^{SM}$2012.01 with an “in foods” claim. For Final Action in 2016, the matrix claim was reduced to rice- and corn-based matrixes. Objective Therefore, R-Biopharm decided to start a collaborative study to demonstrate the wide applicability of Official Method 2012.01 for the quantitative analysis of gliadin in soy, starches, pseudo cereals, legumes, spices, juice, nut nougat crème, cream cheese, pesto, meat, vegetarian meat alternative, cookies, dessert, cake, fish, bread, candies, and potatoes. Materials for incurring were the MoniQA wheat flour and the PWG gliadin preparation. Results Gliadin levels ranged from 3.4 up to 27.4 mg gliadin per kg. The results of the collaborative study with 14 participating laboratories showed recoveries ranging from 80 to 130%. Relative reproducibility standard deviations for contaminated samples were between 9.8 and 27.7%. Conclusions The collaborative study results confirmed that the method is accurate and suitable to measure gliadin in important gluten-free food matrixes. Highlights The title and applicability statement of Official Method 2012.01 were changed as proposed

Decoloration of wine and subsequent enzymatic quantification of histamine

We would like to present a simple decoloration procedure for (red) wine and the subsequent enzymatic method for the specific quantification of histamine. The test kit for sample preparation contains three solutions that are used to decolorate wine by two simple precipitation steps within 15 min. The enzymatic test kit consists of a microtiter plate coated with two substrates and ready to use reagents (buffer, calibrators and enzyme histamine dehydrogenase). The determination is performed within 15 min and the measurement wavelength is 450 nm which is the common wavelength for ELISA procedures. The linear range is from 1 to 20 mg/L in the extracted sample (corresponding to 2.4–48 mg/L in wine) and the recovery is >85% in red wines and more than 90% in white and rose wines. The limit of quantification is calculated to 1 mg/L. Wines at this low histamine levels showed CVs of less than 7%. The assay shows a high precision with a relative within-lab reproducibility standard deviation of less than 7%. A method comparison between HPLC and the new enzymatic system revealed a very high degree of agreement. The enzymatic procedure contains no dilution steps, no washing steps like for an ELISA, and a clear defined end-point of the enzymatic reaction

Decoloration of wine and subsequent enzymatic quantification of histamine

We would like to present a simple decoloration procedure for (red) wine and the subsequent enzymatic method for the specific quantification of histamine. The test kit for sample preparation contains three solutions that are used to decolorate wine by two simple precipitation steps within 15 min. The enzymatic test kit consists of a microtiter plate coated with two substrates and ready to use reagents (buffer, calibrators and enzyme histamine dehydrogenase). The determination is performed within 15 min and the measurement wavelength is 450 nm which is the common wavelength for ELISA procedures. The linear range is from 1 to 20 mg/L in the extracted sample (corresponding to 2.4–48 mg/L in wine) and the recovery is >85% in red wines and more than 90% in white and rose wines. The limit of quantification is calculated to 1 mg/L. Wines at this low histamine levels showed CVs of less than 7%. The assay shows a high precision with a relative within-lab reproducibility standard deviation of less than 7%. A method comparison between HPLC and the new enzymatic system revealed a very high degree of agreement. The enzymatic procedure contains no dilution steps, no washing steps like for an ELISA, and a clear defined end-point of the enzymatic reaction

Quality System Implementation in the Consumer Rights Protection Centre

Oļegs Požiļenko. Bakalaura darbs „Kvalitātes vadības sistēmas ieviešana Latvijas Patērētāju tiesību aizsardzības centrā”. Bakalaura darba mērķis ir, pamatojoties uz teorijā sniegtajām atziņām par kvalitātes vadības aspektiem, novērtēt kvalitātes vadības sistēmas ieviešanas nepieciešamību un iespējas Patērētāju tiesību aizsardzības centrā. Pirmajā nodaļā ir sniegts izvēlētās tēmas teorētiskais pamatojums. Otrajā nodaļā ir sniegts PTAC darbības raksturojums un analīze, kā arī identificētas galvenās problēmas tā darbībā. Trešajā nodaļā ir izskatītas KVS ieviešanas iespējas PTAC. Nobeigumā izklāstīti autora secinājumi un sniegti priekšlikumi PTAC KVS veiksmīgai ieviešanai un uzturēšanai. Bakalaura darba izstrādē izmantoti 20 resursi. Bakalaura darba apjoms ir 66 lappuses, tajā iekļautas 4 tabulas, 21 attēls un 2 pielikumi. Atslēgvārdi: kvalitāte, patērētāji, kvalitātes vadības sistēma.Oleg Pozhilenko. Bachelor’s work thesis „Quality Management System implementation in The Consumer Rights Protection Centre of Latvia”. Bachelor's work is based on the theory of an opinion on the quality management aspects, to evaluate the quality management system implementation and the possible need in The Consumer Rights Protection Centre of Latvia The first chapter consists the themes of the theoretical basis. The second chapter consists operating characteristics and problems of definition of The Consumer Rights Protection Centre of Latvia. The third chapter consists Quality Management System implementation in The Consumer Rights Protection Centre of Latvia. Finally presents conclusions and proposals of tackling. Bachelor’s work used 20 sources, 4 tables, 21 pictures and 2 attachments. Bachelor’s work amounts of 66 pages. Key words: quality, consumers, Quality Management System