Helene Hopfer, Ph.D.

Research Interests

Our research focuses on the human-food interface, and how food composition and structure affects human perception and food choice. We combine human sensory and consumer science with analytical chemistry, instrumental analysis, and multivariate statistics, to elucidate the impact of production, processing, storage, and presentation on perception. We are also interested in improving flavor of fruits and vegetables by linking sensory science to the breeding process more effectively.

Students

I am part of the Food Science and International Agriculture & Development graduate programs.

Current Students

• Ashley Gruman, 1st year M.S. student FDSC (co-advised with J. Hayes)
• Kristin Joy Leong-Fern, 1st year M.S. student FDSC (co-advised with J. Hayes)
• Madison Tarrance, 1st year M.S. student FDSC (co-advised with J. Lambert)
• Astrid D'Andrea, 2nd year M.S. student FDSC (co-advised with J. Hayes)
• Sydney Tankard, 2nd year M.S. student FDSC (co-advised with J. Hayes)
• Morgan Failla, Ph.D. candidate FDSC & INTAD (co-advised with J. Wee)

Graduate Students

• Cynthia Loi, M.S. FDSC, 2024 (co-advised with J. Hayes)
• Nixon Meneses Marentes, M.S. FDSC & INTAD, 2022
• Jennifer Goza, Ph.D. FDSC & INTAD, 2022
• Allison Brown, Ph.D. FDSC & INTAD, 2021
• Alden Riak, M.S. FDSC, 2021
• Isabel Gutierrez, M.S. FDSC & INTAD, 2021 (co-advised with J. Lambert)
• Benjamin Chrisfield, Ph.D. FDSC, 2020 (co-advised with R. Elias)
• Stephanie Keller, M.S. FDSC, 2020 (co-advised with R. Elias)
• Marielle Donohue, M.S. FDSC, 2020
• Andrew Poveromo, M.S. FDSC, 2019
• Gloria Wang, M.S. FDSC, 2018

Honors Students

• Rose Spahn, Schreyer Scholar, BS FDSC, 2023
• Aaron Wiedemer, Schreyer Scholar, BS FDSC, 2022
• Matthiew Haines, Millenium Scholar, BS FDSC, 2021
• Jacob Ginn, Schreyer Scholar, BS FDSC, 2019
• Shannon Brady, Schreyer Scholar, BS FDSC 2018

Awards

• NACTA Teaching Award of Merit, 2020
• Anna and Guy Bixler Memorial Award in Food Science, 2019
• Finalist AGRO New Investigator Award, 2014
• Weurman Symposium Student Award, 2008

Peer Reviewed Publications

see also ORCID and Google Scholar

2024

Meneses-Marentes N, Bharath SM, Hopfer H (2024) Effect of the addition of cocoa sweatings and time of fermentation on flavor compounds and sensory perception of 100% roasted cocoa liquor. J Food Sci (accepted) DOI:10.1111/1750-3841.17404

Spinelli S, Hopfer H, Moulinier V, Prescott J, Monteleone E, Hayes JE (2024) Distinst sensory functions for sourness in adults. Food Qual Prefer 116:105152 DOI:10.1016/j.foodqual.2024.105152

Weikart DK, Coleman KM, Sweet MG, McAmis AM, Hopfer H, Neilson AP, Lambert JD (2024) Cocoa and Polyphenol-Rich Cocoa Fractions Fail to Improve Acute Colonic Inflammation in Dextran Sulfate Sodium-Treated Mice. Mol Nutr Food Res 68(15):2400431 DOI:10.1002/mnfr.202400431

Brodock JL, Hopfer H, Masterson TD, Hayes JE (2024) Orthorexia Nervosa and Healthy Orthorexia in a Physically Active North American Population. Nutrients 16(8):1107 DOI:10.3390/nu16081107

Ma KK, Ziegler GR, Hopfer H, Hayes JE (2024) What Is Chalky? Investigating Consumer Language and Perception of Fine Particles in Beverages Containing Pea and Potato Starch. Foods 13(12):1852 DOI:10.3390/foods13121852

Lawler O, Masterson T, Petersen K, Hopfer H, Gettings MA, Denmon A, Zlotorzynski S, Kris-Etheron P (2024) Online Nutrition Education Videos Teaching How to Use Herbs and Spices to Improve Diet Quality. J Nutr Edu Behav 56(9):P672 DOI:10.1016/j.jneb.2024.05.231

Zhang L, Bedford B, Warren J, Sharma G, Brown AL, Hopfer H, Ziegler GR, Jackson LS (2024) Effectiveness of Dry Cleaning Treatments for Removing Milk Chocolate from Valve/Pipe Assemblies and Pilot-scale Chocolate Processing Equipment. J Food Protec 87(10):100346 DOI:10.1016/j.jfp.2024.100346

Kelley K, Centinari M, Hopfer H (2024) Evaluating white wine consumer interest in Grüner Veltliner: a potential signature varietal for Pennsylvania. International Journal of Wine Business Research 36(3):301 DOI:10.1108/IJWBR-04-2023-0020

2023

Zhou J, Hopfer H, Kong L (2023) Odor-scavenging capabilities of pre-formed “empty” V-type starches for beany off-flavor compounds. Food Hydrocolloids 147:109315 DOI:10.1016/j.foodhyd.2023.109315

Failla M, Hopfer H, Wee J (2023) Evaluation of public submissions to the USDA for labeling of cell-cultured meat in the United States. Front Nutr 10:1197111 DOI:10.3389/fnut.2023.1197111

Petersen KS, Fulgoni III VL, Hopfer H, Hayes JE, Gooding R, Kris-Etherton P (2023) Herbs/spices to Enhance the Flavor of Commonly Consumed Foods Reformulated to Be Healthier Is an Effective and Acceptable Strategy to Lower Intake of Saturated Fat and Sodium. J Acad Nutr Diet DOI:10.1016/j.jand.2023.07.025

Ma KK, Madhavan A, Etter NM, Hopfer H, Hayes JE (2023) Texture term usage and hedonic ratings in two age-diverse cohorts of Americans. J Text Stud DOI:10.1111/jtxs.12791

Brown AL, Warren ER, Ingraham BW, Ziegler GR, Hopfer H (2023) The effect of fat content on sensory perception and consumer acceptability of 70% cacao dark chocolate made from reconstituted cocoa liquor. J Sens Stud e12864 DOI:10.1111/joss.12864

Persico MJ, Smith DE, Smith MS,  Hopfer H, Centinari M (2023) Delaying grapevine budbreak to prevent spring freeze damage impacts Lemberger wine flavour compounds under variable weather conditions. OENO One 57(2) DOI: 10.20870/oeno-one.2023.57.2.7437

Wiedemer AM, McClure AP, Leitner E, Hopfer H (2023) Roasting and Cacao Origin Affect the Formation of Volatile Organic Sulfur Compounds in 100% Chocolate. Molecules 28(7):3038 DOI:10.3390/molecules28073038
 
Wendelin M, Bauer A, Buchinger E, Danner L, Derndorfer E, Hang VTM , Hopfer H, Wallner M, Jantathai S, Julius N, Matullat I, Majchrzak D, Siegmund B, Seo H-S, Spangl B, Duerrschmid K (2023) A cross-cultural study on odor-elicited life stage-associations. Food Qual. Prefer. 106:104810 DOI:10.1016/j.foodqual.2023.104810

Farcuh M, Hopfer H (2023) Aroma volatiles as predictors of chilling injury development during peach (Prunus persica (L) Batsch) cold storage and subsequent shelf-life. Postharv. Biol. Technol. 195:112137 DOI: 10.1016/j.postharvbio.2022.112137

2022

Weikart DK, Indukuri VV, Racine KC, Coleman KM, Kovac J, Cockburn DW, Hopfer H, Neilson AP, Lambert JD (2022) Effect of processing on the anti-inflammatory efficacy of cocoa in a high fat diet-induced mouse model of obesity. J. Nutr. Biochem. 109:109117 DOI: 10.1016/j.jnutbio.2022.109117

Goza JL, Ziegler GR, Wee J, Hayes JE, Hopfer H (2022) Salivary α-amylase activity and flow rate explain differences in temporal flavor perception in a chewing gum matrix comprising starch-limonene inclusion complexes. Food Res. Intern. 158:111573 DOI: 10.1016/j.foodres.2022.111573

Hopfer H, Riak AC, Roberts RF, Hayes JE, Ziegler GR (2022) Synergistic and antagonistic ingredient interactions as a sugar reduction strategy in chocolate milk. J. Sens. Stud. 37(5):e12770 DOI: 10.1111/joss.12770

Elder AS, Coupland JN, Hopfer H, Elias RJ (2022) Effect of alkyl chain length on the antioxidant activity of alkylresorcinol homologs in low-moisture crackers. LWT 164:113637 DOI: 10.1016/j.lwt.2022.113637

McClure AP, Hopfer H, Grün IU (2022) Optimizing consumer acceptability of 100% chocolate through roasting treatments and effects on bitterness and other important sensory characteristics. Curr. Res. Food Sci. 5:167-174 DOI:10.1016/j.crfs.2022.01.005

2021

Hopfer H, McDowell EH, Nielsen LE, Hayes JE (2021) Preferred beer styles influence both perceptual maps and semantic descriptions of dry hops. Food Qual. Prefer. 94:104337 DOI:10.1016/j.foodqual.2021.104337

Ledley AJ, Elias RJ, Hopfer H, Cockburn DW (2021) A Modified Brewing Procedure Informed by the Enzymatic Profiles of Gluten-Free Malts Significantly Improves Fermentable Sugar Generation in Gluten-Free Brewing. Beverages 7:53 DOI:10.3390/beverages7030053

Kelley KM, Todd MJ, Hopfer H, Centinari M (2021) Identifying wine consumers interested in environmentally sustainable production practises. International Journal of Wine Business Research DOI:10.1108/IJWBR-01-2021-0003

Todd MJ, Kelley KM, Hopfer H (2021) USA Mid-Atlantic Consumer Preferences for Front Label Attributes for Local Wine. Beverages 7:22 DOI:10.3390/beverages7020022

Brodock L, Masterson TD, Hayes JE, Hopfer H (2021) Differences in preferred fat level, sweetener type, and amount of added sugar in chocolate milk in a choice task relate to physical activity and orthorexia. Appetite 163:105214 DOI:10.1016/j.appet.2021.105214

Chrisfield BJ, Hopfer H, Elias RJ (2021) Impact of Copper-Based Fungicides on the Antioxidant Quality of Ethanolic Hop Extracts. Food Chem 355:129551 DOI:10.1016/j.foodchem.2021.129551

Wang HL, Hopfer H, Cockburn DW, & Wee J (2021) Characterization of Microbial Dynamics and Volatile Metabolome Changes During Fermentation of Chambourcin Hybrid Grapes from Two Pennsylvania Regions. Front Microbiol 11:3454 DOI:10.3389/fmicb.2020.614278

Brown AL, Bakke AJ, Hopfer H (2021) Understanding American premium chocolate consumer perception of craft chocolate and desirable product attributes using focus groups and projective mapping. PloS ONE 15(11): e0240177 DOI:10.1371/journal.pone.0240177

2020

Chrisfield BJ, Hopfer H, Elias RJ (2020) Impact of Copper Fungicide Use in Hop Production on the Total Metal Content and Stability of Wort and Dry-Hopped Beer. Beverages 6:48 DOI:10.3390/beverages6030048

Gaby JM, Bakke AJ, Baker AN, Hopfer H, Hayes JE (2020) Individual Differences in Thresholds and Consumer Preferences for Rotundone Added to Red Wine. Nutrients 12:2522 DOI:10.3390/nu12092522

Tanabe CK, Nelson J, Boulton RB, Ebeler SE, Hopfer H (2020) The Use of Macro, Micro, and Trace Elemental Profiles to Differentiate Commercial Single Vineyard Pinot noir Wines at a Sub-Regional Level. Molecules 25:2552 DOI:10.3390/molecules25112552

2019

Poveromo AR, & Hopfer H (2019) Temporal Check-All-That-Apply (TCATA) Reveals Matrix Interaction Effects on Flavor Perception in a Model Wine Matrix. Foods 8(12): 641 DOI: 10.3390/foods8120641

Racine KC, Wiersema BD, Griffin LE, Essenmacher LA, Lee AH, Hopfer H, Lambert JD, Stewart AC, & Neilson AP (2019) Flavanol Polymerization Is a Superior Predictor of α-Glucosidase Inhibitory Activity Compared to Flavanol or Total Polyphenol Concentrations in Cocoas Prepared by Variations in Controlled Fermentation and Roasting of the Same Raw Cocoa Beans. Antioxidants. 8(12): 635. DOI: 10.3390/antiox8120635

Elgaard L, Mielby LA, Hopfer H, & Byrne DV (2019) A comparison of two sensory panels trained with different feedback calibration range specifications via sensory description of five beers. Foods 8(11): 534. DOI: 10.3390/foods8110534

Hamada TY, Brown A, Hopfer H, & Ziegler GR (2019) Flavor and mouthfeel of pseudo‐cocoa liquor: Effects of polyphenols, fat content, and training method. J. Sens. Stud. e12541. DOI: 10.1111/joss.12541

Shi, L, Hopfer H, Ziegler GR, & Kong L (2019) Starch-menthol inclusion complex: structure and release kinetics. Food Hydrocolloids. 105183. DOI: 10.1016/j.foodhyd.2019.105183

Wang G, Bakke AJ, Hayes JE, & Hopfer H (2019) Demonstrating cross-modal enhancement in a real food with a modified ABX test. Food Qual. Prefer. 77:206. DOI: 10.1016/j.foodqual.2019.05.007

2018

Wang G, Hayes JE, Ziegler G, Roberts R, & Hopfer H (2018) Dose-Response Relationships for Vanilla Flavor and Sucrose in Skim Milk: Evidence of Synergy. Beverages. 4(4):73. DOI: 10.3390/beverages4040073

Cotter AR, & Hopfer H (2018) The Effects of Storage Temperature on the Aroma of Whole Bean Arabica Coffee Evaluated by Coffee Consumers and HS-SPME-GC-MS. Beverages. 4(3):68. DOI: 10.3390/beverages4030068

2017

Godshaw J, Hopfer H, Nelson J, & Ebeler SE (2017) Comparison of dilution, filtration, and microwave digestion sample pretreatments in elemental profiling of wine by ICP-MS. Molecules. 22(10):16094. DOI: 10.3390/molecules22101609

Johnson AJ, Hopfer H, Heymann H, & Ebeler SE (2017) Aroma Perception and Chemistry of Bitters in Whiskey Matrices: Modeling the Old-Fashioned. Chem. Percept. 10(4):135 DOI: 10.1007/s12078-017-9229-3

Elias RJ, Hopfer H, Hofstaedter AN, & Hayes JE (2017) Man vs. Machine: A Junior‐Level Laboratory Exercise Comparing Human and Instrumental Detection Limits. J. Food Sci. Edu. 16(3):72 DOI: 10.1111/1541-4329.12114

Tanabe CK, Hopfer H, Ebeler SE, Nelson J, Conklin SD, Kubachka KM, & Wilson RA (2017) Matrix extension and multilaboratory validation of arsenic speciation method EAM § 4.10 to include wine. J. Agric. Food Chem. 65(20):4193 DOI: 10.1021/acs.jafc.7b00855

Hopfer H, Gilleland G, Ebeler SE, & Nelson J (2017) Elemental Profiles of Whisk(e)y Allow Differentiation by Type and Region. Beverages 3(1):8 DOI:10.3390/beverages3010008

Blanco-Ulate B, Hopfer H, Figueroa-Balderas R, Ye Z, Rivero RM, Albacete A, Pérez-Alfocea F, Koyama R, Anderson MM, Smith RJ, Ebeler SE, & Cantu D (2017) Red blotch disease alters grape berry development and metabolism by interfering with the transcriptional and hormonal regulation of ripening. J. Exp. Bot. erw506. DOI: 10.1093/jxb/erw506

2016

Hendrickson D, Lerno L, Hjelmeland A, Ebeler S, Heymann H, Hopfer H, Block K, Brenneman C, & Oberholster A (2016) Machine harvesting: The impact of machine harvesting with and without optical berry sorting on Pinot Noir wine composition and quality. Wine & Viticulture Journal 31(5):51. Link

Hopfer H, Jodari F, Negre-Zakharov F, Wylie PL, & Ebeler SE (2016) A HS-SPME-GC-MS/MS Method for the Rapid and Sensitive Quantitation of 2-Acetyl-1-Pyrroline in Single Rice Kernels. J. Agric. Food Chem. 64:4114 DOI: 10.1021/acs.jafc.6b00703

Hendrickson A, Lerno LA, Hjelmeland AK, Ebeler SE, Heymann H, Hopfer H, Block KL, Brenneman CA, & Oberholster A (2016) Impact of Mechanical Harvesting and Optical Berry Sorting on Grape and Wine Composition. Am. J. Enol. Vitic. 67(4):385 DOI: 10.5344/ajev.2016.14132

Tanabe CK, Hopfer H, Gilleland G, Liba A, Ebeler SE, & Nelson J (2016) Total Arsenic Analysis in Californian Wines with Hydride Generation - Microwave Plasma - Atomic Emission Spectroscopy (HG-MP-AES). J. Anal. At. Spectrom. 31:1223 DOI: 10.1039/C6JA00051G

2015

Hopfer H, Nelson J, Ebeler SE, & Heymann H. (2015) Correlating Wine Quality Indicators to Chemical and Sensory Measurements. Molecules 20:8453 DOI: 10.3390/molecules20058453

Ghanem E, Hopfer H, Navarro A, Ritzer M, Mahmood L, Fredell M, Cubley A, Bolen J, Fattah R, Reasdale K, Lieu L, Chua T, Kim D, Marini F, Heymann H, & Anslyn EV (2015) Predicting the Composition of Red Wine Blends using an Array of Multicomponent Peptide-Based Sensors. Molecules 20:9170 DOI: 10.3390/molecules20059170

Nelson J, Hopfer H, Gilleland G, Cuthbertson D, Boulton RB, and Ebeler SE (2015) Elemental Profiling of Malbec Wines Made Under Controlled Conditions by Microwave Plasma Atomic Emission Spectroscopy. Am. J. Enol. Vitic. 66:373 DOI:10.5344/ajev.2015.14120.

Nelson J, Hopfer H, Silva F, Wilbur S, Chen JM, Ozawa S, & Wylie P (2015) Evaluation of GC-ICP-MS/MS as a New Strategy for Specific Hetero-Atom Detection of Phosphorus, Sulfur, and Chlorine Determination in Foods. J. Agric. Food Chem. 63:4478 DOI: 10.1021/jf506372e

Hopfer H, Collins TS, Nelson J, Heymann H, & Ebeler SE (2015) The combined impact of vineyard origin and processing winery on the elemental profile of red wines. Food Chem. 172:486 DOI: 10.1016/j.foodchem.2014.09.113

Umali AP, Ghanem E, Hopfer H, Hussain A, Kao Y, Zabanal LG, Wilkins BJ, Hobza C, Quach DK, Fredell M, Heymann H, & Anslyn EV (2015) Grape and wine sensory attributes correlate with pattern-based discrimination of Cabernet Sauvignon wines by a peptidic sensor array. Tetrahedron 71:3095 DOI: 10.1016/j.tet.2014.09.062

2014

Hopfer H, & Heymann H (2014) Corrigendum to “Judging wine quality: Do we need experts, consumers or trained panelists?"[Food Qual. Prefer. 32 (2014) 221–233]. Food Qual. Prefer. 36:1 DOI:10.1016/j.foodqual.2014.02.010

Hopfer H, Nelson J, & Ebeler SE (2014) How trace element analysis provides important insight into wine chemistry. Spectroscopy 29(9):34 Link

Blackman JW, Hopfer H, Saliba AJ, Schmidtke LM, & Scollary GR (2014) Sensory characterization of Hunter Valley Semillon aged in bottle. Flavour Fragr. J. 29:340 DOI: 10.1002/ffj.3211

Mielby LH, Hopfer H, Jensen S, Thybo AK, & Heymann H (2014) Comparison of Descriptive Analysis, Projective Mapping and Sorting Performed on Pictures of Fruit and Vegetable Mixes. Food Qual. Prefer. 35:86 DOI: 10.1016/j.foodqual.2014.02.006

Hopfer H, & Heymann H (2014) Judging wine quality: Do we need experts, consumers or trained panelists? Food Qual. Prefer. 32:221 DOI:10.1016/j.foodqual.2013.10.004

2013

Heymann H, Hopfer H, & Bershaw D (2013) An exploration of the perception of minerality in white wines by projective mapping and descriptive analysis. J. Sens. Stud. 29:1 DOI: 10.1111/joss.12076

Casassa LF, Beaver CW, Mireles M, Larsen RC, Hopfer H, Harbertson JF, & Heymann H (2013) Influence of Fruit Maturity, Maceration Length, and Ethanol Amount on Chemical and Sensory Properties of Merlot Wines. Am. J. Enol. Vitic. 64:437 DOI: 10.5344/ajev.2013.13059

Hopfer H, Nelson J, Mitchell AE, Ebeler SE, & Heymann H (2013) Profiling the trace metal composition of wine as a function of storage temperature and packaging type. J. Anal. At. Spectrom. 28:1288 DOI: 10.1039/C3JA50098E

Hopfer H, Buffon PA, Ebeler SE, & Heymann H (2013) The combined effects of storage temperature and packaging type on the sensory and chemical properties of Cabernet Sauvignon. J. Agric. Food Chem. 61:3320 DOI: 10.1021/jf3051736

Hopfer H, & Heymann H (2013) A summary of Projective Mapping observations - The effect of replicates and shape, and individual performance measurements. Food Qual. Prefer. 28:164 DOI: 10.1016/j.foodqual.2012.08.017

2012

King ES, Hopfer H, Haug M, Dorsi J, Heymann H, Crisosto G, & Crisosto C (2012) Describing the Appearance and Flavor Profiles of Fresh Fig (Ficus carica L.) Cultivars. J. Food Sci. 77: S419 DOI: 10.1111/j.1750-3841.2012.02994.x

Hopfer H, Ebeler SE, & Heymann H (2012) The combined effects of storage temperature and packaging type on the sensory and chemical properties of Chardonnay. J. Agric. Food Chem. 60:10743 DOI: 10.1021/jf302910f

Hopfer H, Ebeler SE, & Heymann H (2012) How blending affects the sensory and chemical properties of red wine. Am. J. Enol. Vitic. 63:313 DOI: 10.5344/ajev.2012.11112

2011

Hopfer H, Haar N, Stockreiter W, Sauer C, & Leitner E (2011) Combining different analytical approaches to identify odor formation mechanisms in polyethylene and polypropylene. Anal. Bioanal. Chem. 402:903 DOI: 10.1007/s00216-011-5463-8

2010

Hopfer H, Sauer C, Haar N, & Leitner E (2010) Comparison of different analytical methods for volatile and odour-active substances in polyolefins. Macromol. Symp. 296:176 DOI: 10.1002/masy.201051026