The effects of water on tannin levels in grape development - Part four: How does this help us understand dry farmed sites?

In February I had the pleasure of speaking at the Oregon Wine Industry Symposium on a panel talking about grape and wine tannins. Anna Matzinger, Steve Price and I wanted to clarify what tannins are, how their levels in wine affect texture and structure of the wine, where tannins come from, the role of soil moisture on grape tannin levels and how harvest date affects quality of tannins.

I was tasked with talking about the relationship between soil water status and grape tannin levels. It was a great opportunity to improve my understanding of the relationship, and helped me come to terms with the difference between dry farming here in the Willamette Valley and the irrigated vineyards in Southern Oregon. On dry farmed sites factors like soil type, depth and texture, along with the seasonal rainfall have a profound effect on tannin level. In vineyards where there isn’t enough soil moisture to sustain the vines for the entire season, supplementary irrigation is needed. In those vineyards you have more control over the tannin levels of the grapes. To understand this topic and prep for my panel discussion, I studied three key disciplines: 1) soil science; 2) plant physiology; and 3) irrigation management.

Before I get into this I will say that I think the Internet is great for researching topics but I really like books.

PART FOUR: HOW DOES THIS HELP US UNDERSTAND DRY FARMED SITES?

Now that you understand how soil science, plant physiology & irrigation affect grape growing, how will this help us understand dry farmed sites?

1. Sites with deep soils and high PAW, like those on the valley floor, never have enough stress to restrict shoot growth or berry size. They end up producing huge canopies with high amounts of shading and large berries that lack concentration of phenolic compounds.
2. In years where we have low summer rainfall and the shoot tips stop growing before veraison we can confidently predict that the tannin and anthocyanin levels will be higher than average. Subsequent wine quality will also be higher than average.
3. When winemakers talk about the differences in tannin structure between marine sedimentary soils and volcanic soils this could be explained more by the soil tension during the season than the mineral content of the soils.
4. Site selection trumps winemaking every time. You can’t make great wine from deep fertile soils. 

May 6, 2016 at 3:15 PM Permalink

Playing with your food - Kettle Chips part 2

I, on the other hand, have been known to be a chip fiend.  There is never a shortage of chips (Kettle) or crackers in my pantry!  So, you can imagine my delight when I was asked to be part of a Kettle Chip & Wine Pairing tasting.  However, I tend to be a purist when it comes to chips – only straight-up original Kettle Chips for this chip lover.  I was certainly skeptical at the variety of crazy flavors beautifully arranged on the platter before me.  Three crunches in, I was pleasantly surprised at how some of the most unique flavors of chips seemed to bring out the best in the wines and vice versa.  I was particularly shocked at how well the Salt & Vinegar chip paired with the A to Z Pinot Gris.  Who knew?!  That’s what I love about food and wine…  Some of the most unusual combinations sometimes make the most beautiful, unexpected pairings.  So, keep playing with your food!

May 4, 2016 at 2:00 PM Permalink

Playing with your food - Kettle Chips part 1

College days aside, I’ve not really considered a bag of potato chips to be a meal. With the diversity of flavors seen on the grocery shelf these days, however, most of the flavor components of your favorite dish are represented. Sweetness can be found in Honey Barbeque or Maple Bacon flavors, acid in Salt & Vinegar, spicy heat in Jalapeño. Of course, they all have the salt element.

It made sense, then, when I attended a wine tasting here at the winery that took this concept and applied it to wine pairing. We were provided a variety of chips and wine with which to create pairings and see how the flavors came together.

I often mention to folks in the tasting room how well our Chardonnay goes with salt in food. It was a pleasant reminder to see that the humble, plain potato chip could have quite an effect on the flavor of the Chardonnay. It also provided me inspiration for my next movie night snack.

Even more interesting was how the Barbeque flavor and the Maple Bacon both paired so well with Pinot Noir. Both flavors provided a sweetness that complimented the earthy tartness of the wine such that I plan to open a Pinot the next time I heat up the grill.

Perhaps the best part was that this exercise is easily and inexpensively replicated. If you enjoy hosting wine tasting nights with friends, pick up a few bags of chips and see what flavor combinations surprise you.

May 3, 2016 at 5:13 PM Permalink

The effects of water on tannin levels in grape development - Part three: Irrigation

In February I had the pleasure of speaking at the Oregon Wine Industry Symposium on a panel talking about grape and wine tannins. Anna Matzinger, Steve Price and I wanted to clarify what tannins are, how their levels in wine affect texture and structure of the wine, where tannins come from, the role of soil moisture on grape tannin levels and how harvest date affects quality of tannins.

I was tasked with talking about the relationship between soil water status and grape tannin levels. It was a great opportunity to improve my understanding of the relationship, and helped me come to terms with the difference between dry farming here in the Willamette Valley and the irrigated vineyards in Southern Oregon. On dry farmed sites factors like soil type, depth and texture, along with the seasonal rainfall have a profound effect on tannin level. In vineyards where there isn’t enough soil moisture to sustain the vines for the entire season, supplementary irrigation is needed. In those vineyards you have more control over the tannin levels of the grapes. To understand this topic and prep for my panel discussion, I studied three key disciplines: 1) soil science; 2) plant physiology; and 3) irrigation management.

Before I get into this I will say that I think the Internet is great for researching topics but I really like books.

PART THREE: IRRIGATION

By controlling the water applied to plants through irrigation you can study its effects on the growth of the vines, yield and also the fruit chemistry. In dry farmed situations it’s very hard to control the water therefore it is harder to study the effects of water on the vines and fruit.

There have been a lot of studies on irrigation management all over the world and the effects of varying irrigation levels at different points throughout the season. What researchers have found is that by applying less water than the vines are losing to ET between fruit set and veraison, you can control the vine growth and vigor, increase the exposure of the fruit and reduce the berry size. All of these factors help to increase the concentration of tannins and other phenolic compounds in the grapes, desirable in red grapes but less desirable in white grapes.

This understanding has led to wide spread adoption of the irrigation practice called Regulated Deficit Irrigation (RDI) and it is used to improve the quality of red wine grapes. To learn more about RDI visit this site: http://cru.cahe.wsu.edu/CEPublications/EM061E/EM061E.pdf.

Apr 22, 2016 at 3:26 PM Permalink

The effects of water on tannin levels in grape development - Part two: Plant physiology

In February I had the pleasure of speaking at the Oregon Wine Industry Symposium on a panel talking about grape and wine tannins. Anna Matzinger, Steve Price and I wanted to clarify what tannins are, how their levels in wine affect texture and structure of the wine, where tannins come from, the role of soil moisture on grape tannin levels and how harvest date affects quality of tannins.

I was tasked with talking about the relationship between soil water status and grape tannin levels. It was a great opportunity to improve my understanding of the relationship, and helped me come to terms with the difference between dry farming here in the Willamette Valley and the irrigated vineyards in Southern Oregon. On dry farmed sites factors like soil type, depth and texture, along with the seasonal rainfall have a profound effect on tannin level. In vineyards where there isn’t enough soil moisture to sustain the vines for the entire season, supplementary irrigation is needed. In those vineyards you have more control over the tannin levels of the grapes. To understand this topic and prep for my panel discussion, I studied three key disciplines: 1) soil science; 2) plant physiology; and 3) irrigation management.

Before I get into this I will say that I think the Internet is great for researching topics but I really like books.

PART TWO: PLANT PHYSIOLOGY

No one has written a better book on grapevine anatomy and physiology than Markus Keller: The Science of Grapevines, 2010. This was my go to resource for trying to understand how the plant responds to water.

Plants uptake water though their roots via osmosis. It is transported up the xylem to the leaves and out through the stomata. The negative pressure (tension) in the stomata pulls the water from the roots to the leaves. The tension in the leaves has to be greater that the tension in the xylem and the soil to effectively move the water. Therefore the tension in the soil affects the tension in the plant.

An increase in soil tension due to evaporation and transpiration (evapotranspiration or ET) causes a higher increase in xylem tension which, in turn, slows shoot growth and can stop shoot growth all together.

The drying of the soil also causes abscisic acid to be produced (ABA) in the roots. ABA is then transported around the plant where it has many effects.

1. ABA helps regulate stomatal conductance. An increase in ABA closes the stomata so the plant loses less water.
2. ABA works against Auxins which stimulate cell elongation and apical dominance. ABA production, like xylem tension helps to slow and stop shoot growth.

Apr 15, 2016 at 2:25 AM Permalink

Oregon Wine Symposium Part Two: Climatology

Held every year, the Oregon Wine Symposium is marked as "the premier educational event and trade show for the Northwest wine community." This was the first year that I had the pleasure to attend and following this past harvest, I was looking forward to lectures on some pretty hot topics in the Willamette Valley during the 2015 season. For locals you might have picked up on my pun there, but for the uninitiated, let's just say that year after year the Willamette Valley never ceases to surprise with the forecast. We'll get to that in just a moment, but first, an overview.

The two day event is organized by the Oregon Winegrowers Association and is held at the Oregon Convention Center in Portland. It features more than 200 exhibitors on the trade show floor and pulls in guest speakers at the top of their fields, from local icons to world renowned professionals. And perhaps one of the coolest components is that at any point during the symposium you might just bump into one of said icons, personal wine heroes, or the like. 

This year, the lineup of speakers ranged from Patrick Criteser, CEO of Tillamook Country Creamery, to Rich DeScenzo, Group Leader of Microbiology at ETS Laboratories - essentially big picture business to DNA fingerprinting yeast cells in a winery...you get the idea. To say that there is something for every sector of this industry represented at the Symposium is an understatement. That said, there seemed to be one topic that transcended every niche of the wine business because it affects us all - climatology reports.

Dr. Greg Jones, Professor and Research Climatologist at Southern Oregon University, returned this year to provide a wrap-up of the 2015 growing season and some projections for what's ahead in 2016. Slide after slide of his presentation showed us that last year was one for the record books - not just Portland experiencing the most 90 degree days in a calendar year, but 2015 taking the cake as the hottest year in history. With much of the Northwest being victim to an El Niño pattern, we've seen the temperature of the ocean increase, which is even more drastic than land heating. The Arctic Sea ice extent is at its lowest level ever and the temperature gradient between the poles and the equator has dropped, resulting in the jet stream becoming more pronounced. Add to that a statistic like a record breaking accumulation of rainfall in Oregon between December 2015 and February 2016, it's no surprise to see meteorologists, viticulturists, winemakers, and even hospitality managers scratching their heads and wondering what lies ahead.

Queue the projections for 2016: To put it simply, Dr. Jones says to expect more of the current trend. Anywhere from 2012 to 2015 heat or beyond. With California already seeing bud break, I can't imagine we'll be far behind. Karen Peterson, Viticulturists at REX HILL & A to Z Wineworks, reported this morning that we are already seeing wooly bud stage in some vineyards! Will it be another early harvest in 2016? Will the rain let up and tourist season kick off early in the Valley? I guess we'll just have to wait and see. One thing is for certain, we can look forward to another year of surprises and I suspect another seminar full of coverage of what went down at next year's Oregon Wine Symposium.

Mar 31, 2016 at 3:00 PM Permalink

The effects of water on tannin levels in grape development - Part one: Soil science

Last month I had the pleasure of speaking at the Oregon Wine Industry Symposium on a panel talking about grape and wine tannins. Anna Matzinger, Steve Price and I wanted to clarify what tannins are, how their levels in wine affect texture and structure of the wine, where tannins come from, the role of soil moisture on grape tannin levels and how harvest date affects quality of tannins.

Anna Matzinger, Matzinger Davies Wine Company, opened the discussion with a tasting of four Pinot Noir wines from 2015 with tannin levels varying from 250-700mg/L. The wines really highlighted what increasing tannin levels in wine does to the structure and texture of a wine. Anna has a great perspective on wine tannins for she’s been making wine the Willamette Valley for over 15 years now.

Steve Price, S Price Consulting and ETS labs, is a wealth of knowledge on tannins and has spent the last 25 years of his life dedicated to improving the industries understanding of grape and wine tannin. Steve talked about the importance of time to develop tannins and the relationship between catechins and tannins.

I was tasked with talking about the relationship between soil water status and grape tannin levels. It was a great opportunity to improve my understanding of the relationship, and helped me come to terms with the difference between dry farming here in the Willamette Valley and the irrigated vineyards in Southern Oregon. On dry farmed sites factors like soil type, depth and texture, along with the seasonal rainfall have a profound effect on tannin level. In vineyards where there isn’t enough soil moisture to sustain the vines for the entire season, supplementary irrigation is needed. In those vineyards you have more control over the tannin levels of the grapes. To understand this topic and prep for my panel discussion, I studied three key disciplines: 1) soil science; 2) plant physiology; and 3) irrigation management.

Before I get into this I will say that I think the Internet is great for researching topics but I really like books.

PART ONE: SOIL SCIENCE
 

When looking at soil science and viticulture I always reach for my trusty book by Phil Nicholas, Soil, Irrigation and Nutrition (2004). What I learnt was: soils hold water but not all the water is available to the plants because some of it is held to tightly to the soil particles. What’s available to the plants is called Plant Available Water (PAW) and it is influenced by the depth of the soil (or to limiting layer) and by the texture.

• Depth to limiting layer is really easy to understand - as the soil gets deeper the quantity of PAW increases; the shallower the soil the less PAW.
• Texture is defined by the percentage of Sand, Silt and Clay. The texture affects the PAW but it also affects how the water is released from the soil. Below is a soil water release curve for a clay soil, a sand soil and a loam soil. Note how the tension changes as the soil water content decreases for the different soils.  This tension directly affects the plant in a number of ways, particularly how it affects the plant at a certain time point that can change the level of tannins and other phenolic compounds. Soil tension can be measured using tensiometers at various levels in the soil.

Mar 25, 2016 at 12:15 PM Permalink

REX HILL awarded Silver Medal at the Drinks Business Global Pinot Noir Masters

The 2013 REX HILL Willamette Valley Pinot Noir received a Silver medal at the Drinks Business Global Pinot Noir Masters for the second year in a row! Nine Masters of Wine and a Master Sommelier met to judge more than 300 global Pinot Noirs. The Global Pinot Noir Masters recognizes and rewards the finest Pinot Noirs on the world stage and is in its third year of competition. The results will be featured in the April issue of The Drinks Business, as well as online.

Mar 8, 2016 at 2:32 PM Permalink

Oregon Wine Symposium Part One - A to Z & REX HILL Wine Trial Presentation

While attending the Oregon Wine Symposium in Portland last week, A to Z, REX HILL and a few other wineries were able to present some of their research and development projects. I had the opportunity to present a project I supervised last harvest at REX HILL.

There are two distinct phases to make wine from Pinot Noir once the grapes have been harvested and put in a vessel:

1. The Cold Soak Phase which is when the berries or clusters are left soaking in their juice at cold temperature. This is when we will typically extract the anthocyanins, which are pigments responsible for the color of the wine.
2. The Alcoholic Fermentation Phase happens at a warmer temperature, and is when you extract most of the tannins responsible for the structure of the wine.

We designed our trial to be able to quantify how much of the anthocyanins and tannins would be extracted during the cold soak period. After leaving the must for two weeks at 40F we ran our first batch of analyses. We then pulled a barrel worth of juice and fermented it in order to see if the alcoholic fermentation would, in any way, affect these numbers. We were hoping to create a wine that has a dark color but a lighter body. The must left in the tank was fermented traditionally with native yeast and got a couple of daily pump overs or punch downs and would serve as a reference point.

We got some good results from this trial and we thought it would be great to publically share what we have learned. So here I am, presenting the trial, answering questions and explaining why we did what we did to a public who was very appreciative of the conversation. They had the opportunity to taste both wines: the wine made from juice fermented in the barrel and the wine made traditionally. The wine fermented in barrel has a good color, is supple on the palate and exhibits pleasant and rich aromatics; it has been often compared to a wine from Beaujolais. On the other hand, the wine fermented in tank shows concentration, a dark color, complexity and great structure. People had, of course, different opinions on which wine was their favorite but the common factor was that they were all excited by the fact that we were trying to push the envelope of understanding how to make better wines.

From a personal point of view, it was great to interact with some of my fellow colleagues on a subject we are all passionate about. It felt good to be an active member of the Oregon winemaking community and to represent A to Z and REX HILL at a public event.

Mar 7, 2016 at 4:46 PM Permalink

REX HILL named one of

"REX HILL's esteemed roster of estate-grown wines are farmed biodynamically, and the line-up also includes offerings from top Oregon growers. Visitors have the opportunity to sample these wines in a variety of ways, up to a $65 "V.I.P." tour of the vineyard and winery and a tasting of matured wines paired with cheese. Call ahead for information about wine classes and tasting dinners."

Thank you for the kind words Food & Wine Magazine!

Learn more about our tours and tastings

See the list by Food & Wine Magazine

Feb 24, 2016 at 12:25 PM Permalink