TY  - JOUR
A1  - Huschek, Gerd
A1  - Boenick, Josephine
A1  - Loewenstein, Yvonne
A1  - Sievers, Steven
A1  - Rawel, Harshadrai Manilal
T1  - Quantification of allergenic plant traces in baked products by targeted
proteomics using isotope marked peptides
JF  - LWT - food science and technology : an official journal of the Swiss Society of Food Science and Technology (SGLWT/SOSSTA) and the International Union of Food Science and Technology (IUFoST)
N2  - The right choice of analytical methods for plant allergen quantification is a deciding factor for the correct assessment and labeling of allergens in processed food in view of consumer protection. The aim of the present study was to develop a validated target peptide multi-method by LC/MS/MS providing high specificity and sensitivity for plant allergen protein detection, plant identification in vegan or vegetarian products using peptide markers for quantification. The methodical concept considers the selection of target peptides of thermostable allergenic plant proteins (Gly m6 soy, Ses i6 sesame and (beta-conglutin from white lupine) by data base research, BLAST and in silico digestion using Skyline software. Different allergenic concentration levels of these proteins were integrated into our own reference bakery products and quantified with. synthesized isotopically labeled peptides after in-solution digestion using LC/MS/MS. Recovery rates within the range of 70-113% and LOQ of 10 ppm-50 ppm (mg allergenic food/kg) could be determined. The results are independent of thermal processing applied during baking and of epitope binding site for the tested allergens. (C) 2016 Elsevier Ltd. All rights reserved.
KW  - Allergenic food
KW  - Plant allergen (soy, sesame, lupine)
KW  - LC/MS/MS;
 Quantification of allergenic plant traces
KW  - Food labeling
Y1  - 2016
U6  - https://doi.org/10.1016/j.lwt.2016.07.057
SN  - 0023-6438
SN  - 1096-1127
VL  - 74
SP  - 286
EP  - 293
PB  - Elsevier
CY  - Amsterdam
ER  - 
TY  - JOUR
A1  - Bönick, Josephine
A1  - Huschek, Gerd
A1  - Rawel, Harshadrai Manilal
T1  - Determination of wheat, rye and spelt authenticity in bread by targeted peptide biomarkers
JF  - Journal of Food Composition and Analysis
N2  - Adulteration of food and mislabeled products in global market is a major financial and reputational risk for food manufacturers and trade companies. Consequently, there is a necessity to develop analytical methods to meet these issues. An analytical strategy to check the authenticity of wheat, spelt and rye addition in bread products was developed based on database research, in silico digestion confirming peptide specificity and finally quantification by liquid chromatography-tandem mass spectrometry analysis. Peptide markers for wheat (SQQQISQQPQQLPQQQQIPQQPQQF; QQHQIPQQPQQFPQQQQF and QPHQPQQPYPQQ), spelt (ASIVVGIGGQ; SQQPGQIIPQQPQQPSPL) and rye (LPQSHKQHVGQGAL; AQVQGIIQPQQL and QQFPQQPQQSFPQQPQQPVPQQPL) were identified, verified by protein Basic Local Alignment Search Tool and database research and used for quantification in bread. The specific use of multi-reaction monitoring transitions of selected peptides permitted the identification of closely related species wheat and spelt. Other cereal species (emmer, einkorn, barley, maize, rye and oat) were also checked. The target peptides were quantified at different levels using own reference baked products (bread) after in-solution chymotryptic digestion. Sensitivity of the identification was 0.5-1% using flour-based (0-25%) matrix calibration and the analytical recovery in bread was 80-125%. The analytical strategy described here supplies an emerging, independent and flexible tool in controlling the labeling of bread.
KW  - Food analysis
KW  - Food composition
KW  - Food safety
KW  - Plant authentication
KW  - Wheat
KW  - Spelt
KW  - Rye
KW  - LC-MS-MS
KW  - Quantification of peptides
KW  - Food labeling
Y1  - 2017
U6  - https://doi.org/10.1016/j.jfca.2017.01.019
SN  - 0889-1575
SN  - 1096-0481
VL  - 58
SP  - 82
EP  - 91
PB  - Elsevier
CY  - San Diego
ER  -