Corn Varietal Analysis

Funded: $1500 for the next round of seed
Scott Blackwell, Ann Marsh, and Zachary Brenton
SB/AM: have over 7 years of distilling experience and are owners/operators of High Wire Distilling Co. Mr. Blackwell and Ms. Marsh have received numerous awards for their whiskeys, gins, and rums.
Zachary Brenton holds a PhD in genetics/biochemsitry. Dr. Brenton has received over $10million in grant funding and authored over 15 peer review articles ranging from plant composition and biochemistry to specific plant varietal development for bioindsutrial usages. He is currently CTO of Carolina Seed Systems a local agricultural R&D company that helps identify or create custom varietal selection for specific industries.
Dr. Brenton’s experience testing plant varieties and compositional analysis will aid the work of Mr. Blackwell and Ms. Marsh to analyze grain inputs into specialized distillation processes.
In revolt of the monocropping and industrial agriculture that has dominated the past half century, consumers, farmers, and food producers including distillers have sought new ingredients to differentiate products and explore the inherent beneficial properties of heirlooms, landraces, and naturally diverse varieties. Vintners and brewers have long understood the importance of grape and hop varietal selection and the impact on the flavor. However, this same selection intensity is not applied to grain for distillation, specifically corn [Zea mays]. In this project, we plan to demonstrate and detail the differences in composition and biochemistry with known impacts on flavor in order to demonstrate the diversity of possible options and provide a framework on how to select and improve varieties for whiskey production. Specifically, we will analyze typical no. 2 yellow dent corn and Jimmy Red corn. We will highlight the significant differences in macro compositional profile, secondary metabolites, organic acid concentrations. Our objective is to demonstrate to other craft distillers that grain selection is important for flavor and that proper selection can lead to increased value for distiller and a unique experience for consumer. The successful identification of these compounds will allow the industry to make more informed and conscientious decisions in selecting grains used for distillation and provide cost-effective screening methods for quantification of natural biologic compounds inherent to these heirloom grains. In addition, HWD and CSS will lay out specific framework for selecting, curating, and then protecting intellectual property associated with grain selection available to all ADI members.
“Whiskey is unique in that it blends the classic traditions that define it with contemporary technologies and processes that distinguish every barrel. Distillers have long examined the role of water quality, distillation techniques, the ageing process, etc. as they seek to define and redefine the flavor of whiskey. Traditionally, the specific grains that define the mash are of less importance. For example, the bourbon style of whiskey is defined by the utilization of at least 51% corn; however, the variety and characteristics of the corn are undefined. The US Dept of Agriculture has curated over 25,000 unique corn accessions, 40,000 sorghum accessions, and 35,000 small grains accessions (wheat, rye, barely), yet very little research has been dedicated to exploring the role of individual varieties in determining the flavor of distilled products. Each species and variety within these species have unique concentrations of secondary metabolites such as 3-deoxyanthocyanidins and 3-hydroxyflavonoids.
To date, plant scientists are just beginning to elucidate the biochemical mechanisms of flavor, especially in cereals which were primarily grown for caloric values or fermentation efficiency rather than flavor. However, plant scientists have demonstrated the utility and effectiveness of the various analytical chemical methodologies in food products and human nutrition, but few have applied these same approaches to distillation to dictate unique flavors (Arnold et al, Plos One 2019). Obvious vitners have long explored the relationship between grape variety and environment, but now more emphasis is being given to the role of cereals in flavor creation. Several experiments have demonstrated the impacts of wheat and barley varietal selection and its impact on flavor (Herb et al 2017, Faltermair et al 2014)). Multiple Chinese groups have demonstrated that sorghum selection impacts the flavor and quality of baijiu (Disharoon et al 2019, Chen et al 2020). Although outside the scope of this proposal, identifying the biochemical
mechanisms of flavor creation is much easier in grains due to the structured genetic populations, ability to regenerate through seed, and stability of grain biochemistry over time as opposed fruits such as grapes, apples, or pears.

In this proposal, we will utilize advance analytical methodologies to determine the natural biological compounds controlling flavor in corn for bourbon production by examining two different corn varieties all with known differences in secondary metabolites. This research will be important for demonstrating the utility and necessity of grain selection and curation for whiskey production. Our goal is to demonstrate and characterize a sliver of this immense genetic diversity to provide A) quantitative evidence to other distillers that grain varietial selection is important, B) provide a basic framework for selecting and evaluating grain from different varieties, C) a methodology for grain selection, and finally d) provide the framework for protecting distiller’s intellectual property once ideal varieties are discovered.
Carolina Seed Systems is a plant science research and development firm that specializes in the identification and development of crop varieties for specific bioindustrial applications ranging from commodity feed grains to bioenergy to craft whiskey. CSS in collaboration with researchers from Clemson University’s Advanced Plant Technology Program will source and produce the necessary grain needed for the experiment and perform the advanced analytical methods (i.e. HPLC and NIR). Scott Blackwell will utilize the facilities at High Wire Distillery to create new-make distillate for HPLC and NIR analysis. The CSS and CU have a combined 40 years of experience in plant biochemistry analysis. Given the budget, this will achieve our proposed objective and build a base for follow up research sed on internal SC R&D grants as well as federal SBIR grants.
$4,600 for analytical chemistry (40 samples at $115 per sample for both HPLC and NIR). We will utilize samples from previous years experiment.
As more consumers seek and expect differential experiences from spirit makers, new techniques and processes will need to be examined. One area of significant underinvestment is grain quality and varietal selection. Historically, grains were selected for specific end-uses such as forage, feed, or even distillation. Prohibition and then the continual decline of family farms led to the loss of this natural diversity. This is a natural diversity in plant genetics is a raw resource that can be used to distinguish craft distillers from foreign or large distillation operations. In this proposal, we will demonstrate that significant differences do exist in different varieties of corn and then present a cost-effective methodology for screening and identifying these varieties and later securing and protecting the newly identified ingredients. This proposal will give ample resources to further explore the relationships among genetics, environment, and processing.
“Arnold et al. Assessing the impact of corn variety and Texas terroir on flavor and alcohol yield in the new-make bourbon whiskey. Plos One. 8 August 2019
Chen et al. Genome-wide association study of starch content and constitution in sorghum. Journal of Integrative agriculture. 01 November 2019
Disharoon et al. Exploring Diverse sorghum (Sorghum bicolor L. Moench) accessions for malt amylase activity. Journal of the Institute of Brewing. 17 December 2020.
Faltermair et al. Common Wheat (Triticum aestivum L.) and its use as a brewing cereal. Journal of the Institute of Brewing. 09 January 2014.
Herb et al. Effects of Barley (Hordeum vulgare L.) variety and growing environment on beer flavor. Journal of American Society of Brewing Chemists. 05 February 2018.
Zhang et al. Origin Identification of the sauce-flavor Chinese Baijiu by organic acids, trace elements, and stable carbon isotope ratio. Journal of Food Quality. 14 July 2019.