Science - Deep thoughts @bouchetfugacity / by Saarloosandsons

 


Currently we are involved in a secret plot to take over the world. Well, the wine world, and not take over, more like Decode. We are and have been looking at our wine a little differently. We have been looking at our wine on a Molecular basis. Think about that. We have been looking at our wines at the most sub microscopic level possible. And we have been learning a lot. Like 5 Terabytes of A LOT. We can now numerically describe what our wines taste like, We can Show you graphically, what are wines composed of. Rather than taking a sip of our wine, tilting our head back and trying to describe "the color blue"

Trying to describe wine, in my opinion, is like trying to describe the color blue to someone that is colorblind, sure they can see blue, but they see the color blue differently than I do. And I do not presume to know what something smells/tastes like to you. Wine aromatics and flavor is a complex subject. Ultimately, molecules and neurons are the sole determents of these properties. The aromas and flavors of certain spices, flowers, and other fruits, in wine is the sum of molecular transformations that occur during berry development and the winemaking process, along with a little biological voodoo. These processes produce a diverse array of molecules that are perceived by the ~10,000 clonal olfactory neurons in your nose. These olfactory neurons can be divided into subtypes specific for a single molecule or class of molecules. While most of the ~10,000 olfactory neurons in our nose are common amongst all of us, there exists some degree of genetic variation. This accounts for why two people can associate the same molecule with a different aroma or flavor. Flavor for the most part, is actually how the brain interprets the sum of these olfactory inputs. The combinatorial nature of grape metabolism, fermentation biochemistry and human physiology is what gives wine its complex and sometimes dizzying and confusing array of aromas and flavors. Despite this complexity, there is a molecular code that can be cracked and we’ve done it!

Flavonoids are a diverse group of molecules generally referred to aspolyphenols. These molecules determine the color and mouth feel of a wine. Genetic variations in the flavonoid biosynthetic pathway specific to each grape varietal results in quantitative differences in the flavonoid species present in each wine. To illustrate how these variations impact color and mouthfeel, we’ve compared each of our wine’s molecular flavonoid profiles. The heat map on the right shows each wines unique total flavonoid spectrum. Within this space the parameters for each wines color and mouthfeel is defined.

The color of wine is the sum of interaction between unpigmented and pigmented (anthocyanins) flavonoids. In white varietals, such as Grenache Blanc,the pigmented anthocyanins are absent and the unpigmented flavonoids produce a green to gold color. In red varietals the overall diversity of flavonoids is greater due to the presence of anthocyanins. Wine anthocyanins produce colors that range from reddish-brown to purple-blue. Below we’ve extracted the flavonoid profiles of those molecules involved in pigmentation to illustrate how this diversity produces a wine’s color.

 

In addition to color, simple and complex chemical structures of flavonoids contribute to the mouthfeel, or astringent or drying property,of wine. During winemaking and throughout the aging process,complex structures called tannins, which are polymers of flavonoids2 to 50 units in length, form. These higher molecular weight flavonoids have a softer impact your tongue’s taste receptors, whereas monomeric flavonoids are more astringent or bitter. This can be clearly illustrated by comparing how Mother, Family and ExtendedFamily impacts make your tongue tingle or not tingle. We recognize the concept for Wolfhounden might sound a little unfamiliar to most who know Petit Verdot as a blending varietal. There are even those detractors who’ll tell you that Petit Verdot should never be bottled as a single varietal wine. But we ask that these naysayers not sway you because Wolfhounden has some unique organoleptic properties (i.e., color, aromas, flavors, and mouthfeel) that were just too good to hide in a blend. To help you understand these special properties, we’ve gone far beyond standard lab tests found in most tasting sheets and provide you with a full molecular analysis of Wolfhounden to show you at the molecular level what’s responsible for the unique color, mouthfeel, aromas, and flavors of this bold single varietal Petite Verdot.

 

 

COLOR AND MOUTHFEEL—A STUDY IN FLAVONOIDS These two characteristics are attributable to a diverse group of molecules called flavonoids, also known as polyphenols. Genetic variations in the flavonoid biosynthetic pathway specific to Petit Verdot result in increased diversity and quantities of flavonoid species during berry development. This gives Wolfhounden its unique deep purple color and drying mouthfeel. To illustrate how these molecular variations impact color and mouthfeel, we’ve compared the flavonoid profiles of Wolfhounden and MrS, our Pinot Noir. These two wines exist at the opposite ends of the flavonoid spectrum both in color and mouthfeel. You’ll notice the flavonoid profile for Petit Verdot is more complex (grey boxes indicate absence) and the relative levels (indicated by the color intensity of the box) are greater in Petit Verdot. The anthocyanidins and anthocyanins (glucoside conjugates of anthocyanidins) are the pigmented class of flavonoids that give red grape varietals their range of color. Differences in overall diversity and quantities of the purple/blue class of anthocyanidins/anthocyanins, namely the peonidins, petunidins and delphinidins (especially tulipanin) account for Wolfhounden’s deep purple color compared to the light reddish/brown color of Pinot Noir. The drying mouthfeel of Wolfhounden is also due to Petit Verdot’s diverse flavonoid structure. Tannins are polymers of flavonoids, 2 to 50 units in length, which give red wine its characteristic astringent or drying mouth feel property. During winemaking and throughout the aging process flavonoids continually polymerize and increase in length forming higher molecular weight tannins. Due to the way these higher molecular weight tannins interact with the taste receptors on your tongue they are referred to as “softer” because they are not perceived as bitter. The increased diversity and quantities of flavonoids present in Petit Verdot have produced a more complex tannic structure that was softened during the extended barrel-aging period Wolfhounden went through. The final result is Wolfhounden’s big rich tannic structure that is not bitter or overly astringent. If you ever wanted to understand what flavonoids and tannins contribute to a wine, Wolfhounden is your education.

mrS.- The Threads of Haute Couture: About a year ago I meet with Keith to discuss Saarloos and Sons 2010

releases. As he told me the concepts, stories, and those little ‘secrets’ that went into each wine, I could tell there was a 4th dimension he wanted to add to those stories. He then proceeded to tell me how he wanted to go beyond tradition, attempt what no other winery had done before with the 2010 releases and tell the science behind each wine. So we came up with a concept that day to tell the molecular story of the 2010 releases. It is tempting to present the results of this concept here in their entirety but that would be pointless given its depth. So I thought I would start with mrS., the wine Keith likes to describe as Haute Couture. I found this metaphor intriguing because it implies that special techniques and high quality materials were used to make this Pinot Noir. Often from a distance, with the naked eye, it can be difficult to distinguish which of two identical garments was made according to the laws of Haute Couture. The difference only becomes obvious upon finer inspection of the thread quality and stitching techniques. Likewise with wine, our senses can interrogate and distinguish the quality of varietal aromas and flavors but they alone are unable to tell us the nature of those molecular ‘threads’. Traditional wine science attempts to fill that void by giving us information about acidity (measured by pH and titratable acidity, TA), alcohol, and if you’re really luckily some rudimentary chemical analysis bases on the absorbance of light by the molecules in wine (called spectral analysis). We’ve done all this (see the table 1) and we still were not satisfied this information told us the molecular story we wanted to know about the quality of those ‘threads’. So we’ve gone as far as modern science can take us and analyzed each of the 2010 releases at the atomic level. Every organic molecule in nature is primarily composed of carbon, nitrogen, hydrogen, oxygen, and phosphorus. Each of these elements has a defined atomic mass (remember your periodic table of elements) that can be determined using special highly sensitive equipment. These elements are absorbed by the roots of the vine as nutrients and incorporated into higher order organic molecules during berry development by its cellular molecular machinery. This produces the primary metabolites or ‘threads’ of a wine. These metabolites are passed on to the molecular machinery of specific strains of yeast and lactobacillus bacteria where they undergo fermentation reactions that carry out additional molecular modifications. Finally, those metabolites undergo a final slow oxidative touching and gain complexity in an oak barrel. The summation of these molecular processes is wine. Over Table 1: Acid and spectral properties of mrS. pH: 3.78 TA: 0.533g/100ml as H2T Red pigments: 2.74 AU Brown pigments: 3.7 AU Total monomeric anthocyanins: 19.6 mg/mL Total phenols: 46 AU the past year, using ~3.5 million dollars worth of mass spectroscopy equipment (three different methods), 100+ hours of experimental time to generate 1TB of data (and we’re still adding), 200+ hours of computational time (and still analyzing as this is being written), that concept has become a reality. The picture shown here is one result from our initial analysis. It is a heat map that displays the molecular formulas of the 100 most abundant molecules in mrS. listed from top to bottom (red to green) in order of abundance. Although its not obvious by the molecular formulas, the molecules in red at the top of the heat map are primarily flavon-3-ol glycosides and chalcones. These aromatic molecules and their conjugates contribute to the color, aroma, and flavor of the wine. As exciting as the characterization of these 100 molecules are, they represent only 0.3% of the total number of molecules characterized (~2700) and 0.07% of the unique masses identified (~14000) in the raw data. Needless to say, these data have a lot more to say about the metabolite ‘threads’ of mrS. and its status as Haute Couture in the court of Pinot Noir. And as you have guessed, we fully intend to revolutionize viticulture and enology using these novel wine science techniques. How so? Here’s one example. The grapes for the mrS. were sourced from the Santa Rita Hills AVA while those for Extended Family were sourced from the Santa Maria AVA. We’ve recently begun to compare the results from our mrS. and Extended family experiments to identify the molecular differences of Pinot Noir grapes grown in these regions. The application of such knowledge would be limited only by the winemaker’s imagination. So to our

Saarloos and Sons family, consider yourselves the avant-garde of enophiles.

Here’s to the revolution!

Dr. Paul Tarr + Sr Fellow CalTech

Keith Saarloos + son