title: Determination of Protein Content by NIR Spectroscopy in Protein Powder Mix Products.
abstract: Protein is a principal component in commonly used dietary supplements and health food products. The analysis of these products, within the consumer package form, is of critical importance for the purpose of ensuring quality and supporting label claims. A rapid test method was developed using near-infrared (NIR) spectroscopy as a compliment to current protein determination by the Dumas combustion method. The NIR method was found to be a rapid, low-cost, and green (no use of chemicals and reagents) complimentary technique. The protein powder samples analyzed in this study were in the range of 22-90% protein. The samples were prepared as mixtures of soy protein, whey protein, and silicon dioxide ingredients, which are common in commercially sold protein powder drink-mix products in the market. A NIR regression model was developed with 17 samples within the constituent range and was validated with 20 independent samples of known protein levels (85-88%). The results show that the NIR method is capable of predicting the protein content with a bias of ±2% and a maximum bias of 3% between NIR and the external Dumas method.
authors.affiliation: Herbalife International of America Inc., Quality Control, 990 West 190th St, Torrance, CA 90501, USA.
authors.forename: Prashant D
authors.initials: PD
authors.lastname: Ingle
authors.forename: Roney
authors.initials: R
authors.lastname: Christian
authors.forename: Piyush
authors.initials: P
authors.lastname: Purohit
authors.forename: Veronica
authors.initials: V
authors.lastname: Zarraga
authors.forename: Erica
authors.initials: E
authors.lastname: Handley
authors.forename: Keith
authors.initials: K
authors.lastname: Freel
authors.forename: Saleem
authors.initials: S
authors.lastname: Abdo
mesh_terms: D019587:Dietary Supplements / Q000032:analysis*; D005504:Food Analysis; D019906:Nuclear Magnetic Resonance, Biomolecular; D011208:Powders; D012822:Silicon Dioxide / Q000032:analysis*; D030262:Soybean Proteins / Q000032:analysis*; D019265:Spectroscopy, Near-Infrared; D000067816:Whey Proteins / Q000032:analysis*
chemical_list: D011208:Powders; D030262:Soybean Proteins; D000067816:Whey Proteins; D012822:Silicon Dioxide