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Amanda C Stewart

Associate Professor

Amanda Stewart

Amanda Stewart
401-C HABB1 (0924)
1230 Washington Street SW
Blacksburg, VA 24061


  • Ph.D., Food Science, Purdue University, 2013
  • M.S., Agricultural and Biological Engineering, Purdue University, 2004
  • B.S., Agricultural and Biological Engineering, Purdue University, 2003
  • B.S., Biochemistry, Purdue University, 2003

Teaching Responsibilities:

FST 3114/HORT 3114 Wines and Vines

FST 2544/HNFE 2544 Functional Foods for Health

FST 4654 Food and Beverage Fermentation

Research Interests:

In the Enology and Fermentation lab, we work with wine and hard cider quality, and the impact of food and beverage fermentation processes on bioactive compounds relevant to human health.  Current projects include collaborations with horticulture researchers to develop vineyard and orchard management practices for improved wine and cider quality, and the impact of hard cider processing methods on cider chemistry and quality.  Currently, we are investigating the impact of yeast assimilable nitrogen composition and concentration on yeast and bacterial metabolism during and after fermentation, and the impact of juice clarification methods on fermentation and cider polyphenol concentration and composition.  We are also working to develop new, collaborative projects in the area of fermented vegetables and human health.

Peer-Reviewed Journal Articles

Jin, Q., S.F. O’Keefe, A.C. Stewart, A.P. Neilson, Y.T. Kim, H. Huang. 2021. Techno-economic analysis of a grape pomace biorefinery: Production of seed oil, polyphenols, and biochar. Food and Bioproducts Processing. In press (published online 13 February 2021)

Kessinger, J., G. Earnhart, L. Hamilton, K. Phetxumphou, C. Neill, A.C. Stewart, J. Lahne. 2020. Exploring Perceptions and Categorization of Virginia Hard Ciders through the Application of Sorting Tasks. Journal of the American Society of Brewing Chemists. In press (published online 17 Dec. 2020) 

Karl, A.D., M.G. Brown, S. Ma, A. Sandbrook, A.C. Stewart, L. Cheng, A.K. Mansfield, G.M. Peck. 2020. Soil Nitrogen Fertilization Increases Yeast Assimilable Nitrogen Concentrations in ‘Golden Russet’ and ‘Medaille d’Or’ Apples Used for Cider Production. HortScience. 55(8): 1345-1355. 

Karl, A.D., M.G. Brown, S. Ma, A. Sandbrook, A.C. Stewart, L. Cheng, A.K. Mansfield, G.M. Peck. 2020. Foliar urea applications increase yeast assimilable nitrogen concentration and alcoholic fermentation rate in ‘Red Spy’ apples used for cider production. HortScience. 55(8): 1356-1364. 

Poe, N. E., D. Yu, Q. Jin, M.A. Ponder, A.C. Stewart, J.A. Ogejo, H. Wang, H. Huang. 2020. Compositional variability of food wastes and its effects on acetone-butanol-ethanol fermentation. Waste Management. 107: 150-158. 

Jin, Q., Z. Wang, Y. Feng, Y-T. Kim, A.C. Stewart, S.F. O’Keefe, A.P. Neilson, Z. He, H. Huang. 2020. Grape pomace and its secondary waste management: Biochar production for a broad range of lead (Pb) removal from water. Environmental Research. 186: 109442. 

Ma, S., D.G. Steger, P.E. Doolittle, A.H. Lee, L.E. Griffin, A.C. Stewart. 2020. Persistence of Multitasking Distraction Following the Use of Smartphone-based Clickers. International Journal of Teaching and Learning in Higher Education. 32(1): 64-72. 

Griffin, L. C. Diako, L.E. Miller, A.P. Neilson, C.F. Ross, A.C. Stewart. 2020. Preference for and Sensitivity to Flavanol Mean Degree of Polymerization in Model Wines is Correlated with Body Composition. Appetite. 144: 104442. 

Teixeira, G.H., S. Ma, A.C. Stewart, H. Wang, S.F. O’Keefe. 2019. Natamycin photostability in acidified green tea beverage is dependent on mycosporine-like amino acids and epigallocatechin gallate interaction. LWT-Food Science and Technology. 116: 108572. 

Ma, S., C. Kim, A.P. Neilson, L.E. Griffin, G.M. Peck, S.F. O’Keefe, A.C. Stewart. 2019. Comparison of Common Analytical Methods for the Quantification of Total Polyphenols and Flavanols in Fruit Juices and Ciders. Journal of Food Science. 84(8): 2147-2158. 

Griffin, L., D.W. Fausnacht, J.L. Tuzo, A.K. Addington, K.C. Racine, H. Zhang, M.D. Hughes, K.M. England, R.S. Bruno, S.F. O’Keefe, A.P. Neilson, A.C. Stewart. 2019. Flavanol Supplementation Protects Against Obesity-associated Increases in Systemic Interleukin-6 Levels without Inhibiting Body Mass Gain in Mice Fed a High-fat Diet. Nutrition Research 66: 32-47.

Racine, K., A.H. Lee, B.D. Wiersema, H. Huang, J.D. Lambert, A.C. Stewart and A.P. Neilson. 2019. Development and Characterization of a Pilot-Scale Model Cocoa Fermentation System Suitable for Studying the Impact of Fermentation on Putative Bioactive Compounds and Bioactivity of Cocoa. Foods. 8(3), 102 

Racine, K., A.H. Lee, A.C. Stewart, K.W. Blakeslee, A.P. Neilson. 2019. Development of a Rapid Ultra Performance Hydrophilic Interaction Liquid Chromatography Tandem Mass Spectrometry Method for Procyanidins with Enhanced Ionization Efficiency. Journal of Chromatography A. 1594(7): 54-64. 

Ewing, B.L. , G.M. Peck, S. Ma, A.P. Neilson, A.C. Stewart. 2019. Management of Apple Maturity and Postharvest Storage Conditions to Increase Polyphenols in Cider. HortScience. 54(1): 143-148.

Lee, A.H., A.P. Neilson, S.F. O’Keefe, J.A. Ogejo, H. Huang, M. Ponder, H.S. Chu, Q. Jin, G. Pilot, A.C. Stewart. 2019. A Laboratory-scale Model Cocoa Fermentation Using Dried, Unfermented Beans and Artificial Pulp Can Simulate the Microbial and Chemical Changes of an On-farm Cocoa Fermentation. European Food Research and Technology. 245 (2): 511-519.

Teixeira, G.H., L. Morelli, S. Ma, A.C. Stewart, S.F. O’Keefe. 2019. Photoprotective Effect of Mycosporine-like Amino Acid Extracts on Natamycin, Saffron Carotenoids and Epigallocatechin Gallate in Acidified Beverages Exposed to Different Light Sources. International Journal of Food Science & Technology. 54(2): 440-450. 

Ma, S., A.P. Neilson, J. Lahne, G.M. Peck, S.F. O’Keefe, E.K. Hurley, A. Sandbrook, A.C. Stewart. 2018. Juice Clarification with Pectinase Reduces Yeast Assimilable Nitrogen in Apple Juice without Affecting the Polyphenol Composition in Cider. Journal of Food Science. 83(11): 2772-2781. 

Jin, Q., A.P. Neilson, A.C. Stewart, S.F. O’Keefe, Y-T. Kim, M. McGuire, G. Wilder, H. Huang. 2018. Integrated Approach for the Valorization of Red Grape Pomace: Production of Oil, Polyphenols, and Acetone-Butanol-Ethanol. ACS Sustainable Chemistry & Engineering. 6(12): 16279-16286. 

Ma, S., A.P. Neilson, J. Lahne, G.M. Peck, S.F. O’Keefe, A.C. Stewart. 2018. Free Amino Acid Composition of Apple Juices with Potential for Cider Making as Determined by UPLC-PDA. Journal of the Institute of Brewing. 124(4): 467-476. 

Ma, S.,; D.G. Steger, P.E. Doolittle, A.C. Stewart. 2018. Improved Academic Performance and Student Perceptions of Learning Through Use of a Cell Phone-Based Personal Response System. Journal of Food Science Education. 17(1): 27-32. 

Boudreau, T.F.; G.M. Peck, S.F. O’Keefe, A.C. Stewart. 2018. Free Amino Nitrogen Concentration Correlates to Total Yeast Assimilable Nitrogen Concentration in Apple Juice. Food Science & Nutrition. 6(1): 119-123. 

Boudreau, T.F.; G.M. Peck, S. Ma, N. Patrick, S. Duncan, S.F. O’Keefe, A.C. Stewart. 2017. Hydrogen Sulphide Production During Cider Fermentation is Moderated by Pre-Fermentation Methionine Addition. Journal of the Institute of Brewing. 123(4): 553-561. 

Ryan, C.M.; W.Y. Khoo, A.C. Stewart, S.F. O’Keefe, J.D. Lambert, A.P. Neilson. 2017. Flavanol Concentrations Do Not Predict Dipeptidyl Peptidase-IV Inhibitory Activities of Four Cocoas with Different Processing Histories. Food & Function. 8: 746-756. 

Boudreau, T.F.; G. Peck; S. O’Keefe; A.C. Stewart. 2017. The Interactive Effect of Fungicide Residues and Yeast Assimilable Nitrogen on Fermentation Kinetics and Hydrogen Sulfide Production During Cider Fermentation. Journal of the Science of Food and Agriculture. 97(2): 693-704. 

Peck, G.M., McGuire, T. Boudreau, A.C. Stewart. 2016. Crop Load Density Affects ‘York’ Apple Juice and Hard Cider Quality. HortScience. 51(9): 1098-1102. 

Maisonnave, H., A. Matunda, E.K. Hurley, A. Sandbrook, S.F. O’Keefe, A.C. Stewart. 2016. Pre-fermentation Supplementation of Mango Must with Ammonium and Primary Amino Nitrogen Influences Mango Wine Chemistry. African Journal of Food Science and Technology. 7(7): 166-171. 

Thompson-Witrick, K.; K. Goodrich, A.P. Neilson, E.K. Hurley, G.M. Peck, A.C. Stewart. 2014.  Characterization of the Polyphenol Composition of 20 Cultivars of Cider, Processing, and Dessert Apples (Malus xdomestica Borkh.) Grown in Virginia. Journal of Agricultural and Food Chemistry. 62(41): 10181-10191. 

KA Thompson-Witrick, KM Goodrich, AP Neilson, EK Hurley, GM Peck, AC Stewart, 2014. Characterization of the Phenolic Composition of Cider, Processing, and Dessert Apples Grown in Virginia, J Agric Food Chem 62:10181-10191, 2014. DOI: 10.1021/jf503379t

Conference Proceedings

Stewart, A.C., Song, B.J., Burtch, C.E., Butzke, C.E., Ferruzzi, M.G.  2014.  Polyphenol Profiles of Wines Made from American, Eurasian, and Interspecific Wine Grape Varieties.  Proceedings of the Third Edition of the International Conference Series on Wine Active Compounds. Beaune, France, 2014, 26 – 28 March (pp. 451-454). Dijon, France, Universite de Bourgogne.