Location: Food Science Research2013 Annual Report
1a. Objectives (from AD-416):
1. Rapid development and introduction of new potato varieties that have exceptional agronomic, processing and consumer acceptance traits. 2. Explore new methods for rapid and simultaneous measurement of acrylamide content in chips and French fries to meet the high throughput needs of breeding programs and processing industry.
1b. Approach (from AD-416):
Near-infrared (NIR) spectroscopy will be used to develop a more efficient and cost effective method for rapidly analyzing acrylamide in chips and French fries from potatoes as well as sweetpotatoes. Samples of various potato and sweetpotato genotypes containing a wide range of reducing sugar and asparagine contents will be analyzed using chromatographic methods and near infrared (NIR) spectroscopy. The samples will be processed into fried chips and French fries for acrylamide analysis using GC-MS, LC-MS/MS and NIR techniques. Samples will be scanned in the diffuse reflectance mode (400-2500 nm) of NIR spectrometer. The mean NIR spectra of the analyzed samples will be modeled against the data generated by chromatographic methods using partial least square regression (PLSR), and the regression models will be validated by full cross-validation. The NIR methods will be optimized for processed products with the goal of achieving an accuracy of +/-20% in the range of 0-500 ppm acrylamide. Acrylamide is formed primarily from reducing sugars and amino acids especially asparagine. The LC-MS and GC-MS methods currently used to analyze acrylamide is time consuming and expensive.
3. Progress Report:
This project is related to in-house objective number 5: Evaluate advanced sweetpotato genotypes intended for processing applications,postharvest handling systems, and processing technologies for their potential to increase levels of beneficial phytochemicals in concert with production of high quality food products. The project was implemented on November 8, 2012 with a recruited post-doctorate fellow on board to handle the collaborative work at the Department of Horticultural Science, North Carolina State University. Protocols were established for potato sample preparation and acrylamide quantification by gas chromatography-mass spectrometry and near-infrared spectrometry, a rapid method for low cost and high throughput analysis. Initial results showed that the near-infrared method can be used to quantify the acrylamide content in liquid samples, e.g. acrylamide in solutions, potato-water matrix. The limit of quantification for acrylamide content by the near-infrared method was determined. Principal component analysis of near-infrared spectra indicated that the method has the capability to detect different concentrations of acrylamide in water and potato-water matrix with a quantification limit as low as 50 ppb. Progress has been made in the development of predictive models for calibrating the arylamide values obtained by near-infrared and gas chromatography-mass spectrometry methods in French fries prepared from various potato clones. Study on the applications of the near-infrared method in determining the substrate concentrations of the acrylamide reaction (reducing sugars and asparagine) in potato clones was also initiated.