Sunday 29 September 2013

Syringaldazine and sparkling wine

Last week I was preparing for my trip to Champagne that is occurring this week. I will be working with my Colleagues from University of Reims, collecting samples during grape processing. We have had to wait until the CIVC had declared the Vendage dates for Champagne. So I will be going to France on Tuesday night and spending the rest of the week collecting juice samples from a large winery during the key stages of whole-bunch pressing.  Once we have collecting the samples, it will be back to the lab to carry-out key analysis, and then return the next day to collect more samples.

Generally most of France has being experiencing trying grape growing conditions such as late budburst, flooding rains, hail, scorching hot summers months and mostly recently weather conditions conducive to mildew and grey rot. Champagne has not been immune to this problems, and some vineyards are showing a proportion of Botrytis cinerea infection. I will be quantifying how much Laccase or by its technical name benzenediol:oxygen oxidoreductase  (IUBMB Enzyme Nomenclature E.C. 1.10.3.2) has been produced by the infection. One of these easiest ways to quantify the quantity of enzymes is to measure the substrates consumed or the by-products produced.

In my experiments I will be measuring how much Syringaldazine (4-Hydroxy-3,5-dimethoxybenzaldehyde azine) has been consumed per minute of activity.  



Syringaldazine (courtesy of Sigma Aldrich)

They are many methods for measuring this consumption, at different pH, temperature, concentration and buffers.

  • Consumption of 0.5 mM syringaldazine at pH 6.5 and 25 °C (Lante et al. 2000)
  • Consumption of 1.0 mM syringaldazine in citrate-phosphate buffer at pH 5.0 (Minussi et al. 2007)
  • Consumption of 0.216 mM syringaldazine in potassium phosphate buffer at pH 6.5 and 37 °C (McNaughton 2003)
  •  Consumption of 0.01% w/v syringaldazine in sodium acetate buffer (Iland et al. 2004)

The reason syringaldazine is used because it oxidises quickly and produces a distinctive red/magenta colour change at 525-530 nm, which can be measured by visible light spectrophotometer. The increase absorbency at 525/530 can then be related to the amount of syringaldzine consumed and thence the activity of laccase in the sample.



Cuvettes of syringaldzine reaction product




Iland, P., Bruer, N., Edwards, G., et al., 2004. Chemical analysis of grapes and wine: techniques and concepts, Campbelltown: Patrick Iland wine promotions.
Lante, A. et al., 2000. Biodegradation of phenols by laccase immobilised in a membrane reactor. Process Biochemistry, 36(1-2), pp.51–58. Available at: http://linkinghub.elsevier.com/retrieve/pii/S0032959200001801.
McNaughton, G., 2003. Enzymatic assay of laccasse EC 1.10.3.2. Sigma aldrich technical documents. Available at: http://www.sigmaaldrich.com/technical-documents/protocols/biology/enzymatic-assay-of-laccase.html [Accessed September 8, 2013].
Minussi, R.C. et al., 2007. Phenols removal in musts: Strategy for wine stabilization by laccase. Journal of Molecular Catalysis B: Enzymatic, 45(3-4), pp.102–107. Available at: http://linkinghub.elsevier.com/retrieve/pii/S1381117706003444 [Accessed September 4, 2013].





Monday 23 September 2013

"The pure culture is the foundation for all research"

According to Robert Koch, Nobel prize winner and often considered the founder of modern Bacteriology. Koch made important breakthroughs with infectious disease such as Anthrax, Cholera and Tuberculosis. His ideas are still considered important and are used in teaching to this day.


Robert Koch (Courtesy of Wikimedia Commons)

So it it with theme of purity that I mention our new addition to the Jack Ward Laboratory, a Bassaire KV4 vertical laminar flow, which arrived today. Laminar flow cabinets are used in microbiology work to ensure a clean environment is maintained and that no external microbial contamination occurs. 

Laminar Cabinet in place in the Jack Ward laboratory 
They are quite simple in function with a fan sucking air through a high specification filter to remove all aerial contaminants. The clean air is then pushed down into the cabinet, where it is spills out over the work bench. This over-pressure of clean air reduces the contamination of agar plates, ensuring that only the organisms that you are interested in, actually grow on the plates.

We will be using the Laminar flow cabinet initially in the study of lactic acid bacteria. This year my colleague Andrew Atkinson will be investigation the growth of lactic acid bacteria that have a tolerance for low pH and high acidity. We will assessing how well they perform in the harsh acidic conditions of English Sparkling base wines. Hopefully we will be able to establish which strains perform best according to both pH and sulphite tolerance. Interestingly some of the strains we will be testing have originated in the UK, having previously been isolated by Plumpton College students Gwen McCann, David Joyce and Emma Waldron.

  


 

Sunday 22 September 2013

Estate Italiana - Veneto and Friuli-Venezia Giulia


While not strictly 100% oenology, I have been meaning to document my travels from earlier this year, and this blog seems to be a convenient place to put it. 

This summer I visited NE Italy, Austria, Slovakia and the Czech Republic. I sought advice and suggestions about all these countries including where to go, what to do and who to visit. So to return the favour for the wisdom I received I am sharing my experiences.

Perfect Venetian evening

We started the holiday on the Venice beaches.  Most of the time was spent BBQing and drinking Aperol. However on a bar crawl into Venice, we spent a significant amount of time in Osteria alla ciurma in Rialto.  It has a diverse list of local Venetian wines, supplemented by wines from FVG. Traditionally Venice has been a major consumer of wines from its neighbours and they take pride of place in these local drinking spots. The bar all served plenty of top notch Cicchetti to go with the wines. Highlights were a sparkling Refosco and Salmon wrapped in pancetta and the deep fried in tempura. 

On the cultural front we took a trip out to Padua to see the stunning Giotto frescoes of the Scrovegni Chapel. it was a breath taking sight and worth the trip to visit.

Maurizio (Left) and me
Besides the experiencing the joys of the Adriatic, I decided to also find out more about Prosecco by taking a trip to Conegliano Valdoobbiadene. I visited the small producer Malibran Vini and learnt as much as possible from the winemaker Maurizio Favrel, about these wines, how they are grown and what it takes to make them. This was probably one of the best tastings I had during the holiday, starting with Col Fondo Prosecco (sparkling bottled with lees) then moving to more normal Charmat/Autoclavi styles. Interestingly both their driest and sweetest wine styles need to use the very best base wines to achieve the best balance. Last wine on offer was a Sparkling rose made from Rabaso and Incrocio Manzoni Moscato 13.0.25 which is a grape I knew very little about  but took a particular shine to during my trip in Italy.


Cloudy Col Fondo Prosecco 
Vanio Spumante Rose





















From Venice we moved onto the Colli Orientali del Friuli, where we stayed in the vineyards of Aquila Del Torre. I spent some time with the winemaker Michele Ciani touring the wonderfully terraced vineyards tucked up into the Foothills of the Julian mountains.  This is a beautiful spot where the hills have been extensively sculpted into sun-catching terraced bowls, which are both functional as well as striking and highlight the role of people in revealing the terroir of a site.  
South facing Vineyard amphitheatres of Aquila del Torre
Vinous highlights from the winery were the Picolits, a capricious grape that was made in both the traditional sweet style and the rule-breaking dry style that Aquila del Torre call Oasi. A mature Merlot from the family cellars was no slouch either and highlighted NE Italy's long relationship with this international grape.
Picolit grapes shown its distinctive poor set character
Alto Gradimento, food as good as the views
The region of FVG has some wonderful sights, but the one enjoyed most was the amazing mosaic floor of the Basilica of Aquileia. This basilica is now a UNESCO world heritage site due to importance in linking Roman and Christian era's together. While touring the region many people recommend the nearby town of Grado for its beaches, however we found it the most disturbing beach in the world; muddy, tepid and weedy. It it could be best described as like swimming in Miso soup. To redeem our trip to Grado, we ate a modern Italian dinner in the 6th floor Alto Gradimento restaurant in the centre of town had superb views and fresh and lively food. 

Cormons custom built press trays with 3 press cuts
A day spent driving the hills of FVG and Slovenia with my good friend Professor Mario Gregori of the University of Udine lead me to two very different wineries. Firstly was the Cormon’s, a co-operative for more than 200 grower, which was a very slick operation making an extensive portfolio of wine styles, many single varietals as well as distillates. 

The company and winemaker Luigi Soini are innovative in wine making and wine marketing including a long tradition of engaging with famous artists and there is an amazing collection of large oak Botte featuring a diverse range of modern and traditional art pieces. For me the most interesting wine on offer was il Vino della pace (Peace wine). A single vineyard wine comprising over 300 different varieties from all over the world.  From this difficult to manage vineyard, due to natural difference in grapes maturities, flavours, colours, disease pressure etc, they can produce an interesting full-bodied white wine with a intriguing mouth-feel and distinct Muscat aroma twang. 
 
Saša’s new wines
Following on from this large winery was a trip to the decidedly smaller family affair of Radikon. Here I spent time learning the ins and outs of making mature, long lived skin-contact wines. Saša and Stanko generously shared many of their wines, including current release 1999 Merlot, a lovely mature 1998 Ribolla Gialla and the 2000 Fuori dal tempo Duemila.  However my favourites were Saša’s new style wines which are shorter in skin contact to the normal Radikon wines. To me they were fresher, lighter and showing a more invigorating approach.

After this visit we said arrivederci Italy and moved onto to central Europe where I was to visit more places and wineries.



Friday 20 September 2013

Vintage hands and safe winemaking

End of another busy week and I was at loss about what to blog. 

I have just complete a two-day 'Safe winery practices' course for the year 2 wine production students. Safety in the wine industry is important, too many people get injured at work because they fail to understand the risks of the making wine. However while it is important, it can be boring to teach and even more boring to learn.

I do try my best to ensure my students learn how to be safe when the enter the real world of winemaking and hopefully they will never experience an industrial accident or worse, be responsible for one.

One thing I ask them during the lessons is what are the biggest risks they face as winery workers, and the answers usually come back quickly as carbon dioxide and sulphur dioxide. Interestingly these hazards are reasonable well understood, but surprisingly rare. Instead the some of the most common cause of injuries are manual handling, falling from heights, slips and trips and vehicles.



It is an almost mundane list of hazards found in all industries, however I think it is because of this familiarity that they become forgotten especially in the heat of vintage.  
 
Alongside these 'common' hazards there are some unique winery hazards that all new winery workers have to understand and be aware of including:
  • Diatomaceous earth - respiratory problems
  • Caustic soda and other tank cleaning agents - chemical burns
  • Winery hose - trip hazards and manual handling 
  • Forklifts, tractors - vehicle accident
  • Steam - scalds and burns
  • Barrels - manual handling and impact/crush injuries
  and many others
 
One problem that is incredibly common, but often overlooked is the 'vintage hands'. While not life threatening they can be painful, annoying and socially embarrassing (No my car hasn't just broken down!). 

 
Image courtesy of Katnook Estate www.katnookestate.com.au.
During my years as a winemaker I tried many different cleaning ideas including the popular dry citric acid, neat hypochlorite, Solvol etc. Most of these clean your hands but leave them in poor  condition. However in my last vintages at Katnook Estate I came across a product Stoko Reduran which is specialist hand cleaner for the print industry.  It works extremely well on red wine stain and soon everyone in the cellar was using it. When I moved to Italy to work, I made sure I took a tube with me and I discovered my fellow cantineri were often sneaking it from my locker. I now advise all my third year BSc students to take it on vintage with them for use during there Vintage winery placement modules.

Interestingly while on twitter tonight that I saw a tweet from Erica Landin and Nayan Gowda discussing this very topic. It was then I realised that not enough people in the wine industry know about this product and that its worth tweeting and blogging about.

So for those currently or about to vintage, good luck, safe safe and keep your hands clean.

  

Thursday 19 September 2013

The Aroxa challenge comes to Plumpton College

The academic year at Plumpton College has started in earnest today. Our second year wine students have come back from their summer activities to enrol for the new year. Besides enrolling they are doing a short course on 'Safe winery practices' to ensure they can successfully work in the winery. The first year wine students are already enrolled and learning the rules and regulation of higher education, so they can start classes next week.

This year I decided to organise a little competition for the wine students to provide a break from their lessons, to benchmark where they are and inspire them to improve over the coming year. To make this happen we got  technical assistance from Aroxa based in Leatherhead, Surrey.  Aroxa was founded by Dr Bill Simpson of Cara technology (world leader in Brewing science), as a company to supply flavour standards to the Beer industry.  

Flavour standards for those not familiar with them, are high purity odour/flavour compounds, bound to a complexing agent and delivered at the correct dose rate into sample beverage. They allow industry personal to train themselves on the sensory impact of specific compounds with minimal fuss and at dosage rate found in the target beverage.  The can range from ng to mg levels depending on specific odourants.
Capsules containg 22.5 micrograms of Guaiacol for adding to wine  (Aroxa)
These standards are widely used in the beer industry for tasting panel training and validation. They are also used in the cider & water industries and more recently the wine industry.

So today Lee Hinds who is Aroxa's development chemist, came to Plumpton College with a collection of 10 key wine flavours:
  • Vanillin - “Vanilla, like ice cream or custard”
  • Guiaicol - “Smoky, like smoked fish or cheese
  • β Ionone -“Violets, like Turkish delight”
  • β Damescenone - “Damascenone, floral with undertone of red fruits”
  • Isoamyl acetate -“Isoamyl acetate, like bananas or pear drops”
  • 2,3 Butanedione - “Diacetyl, like butter, or butter popcorn”
  • 2 Isobutyl 3 Methoxypyrazine - “Earthy, like green pepper”
  • cis 3 Hexenol - “Freshly cut grass, like hedge cuttings”
  • Lactone - "Like coconut"               
  • Gereniol - “Geraniol, like rose petals”
These flavours were the basis of the 'Aroxa Challange' that we conducted with our wine business and wine production students.

Lee Hinds discussing flavour compounds
First up Lee, gave a standard dose to the students in water and explained the importance of that compound to wine.  Once the students had familarised themselves with the compounds they were presented with 10 blind samples at half strength in a randomised order.  For the student correctly identifying all 10 flavour compounds, they were then challenged to identify flavour mixtures or quarter strength standards until the heat winners we found.

Many interesting things came out from these tastings, firstly many students found out about any personal specific anomsia (inability to detect single smells)  they may have.  Personally I discovered I am odour blind to β Ionone, though I am not alone in this as it is a very common anosmia (approx 50% of people) as shown in this 2006 study by Plotto, Barnes and Goodner. Some student also discovered that while the compounds are detectable, they present a different aroma note to those which others find, a example of this includes lactone presenting as dill/hamburger pickle notes not just the classic coconut aroma.  Finally we collected some simple data on intensity as a way of potentially refining the dose rates in the future.

The students and staff enjoyed the challenge immensely, and some got quite competitive

Sarah Redpath heat 1 winner
Ian Holloway, heat 2 winner

In the end the three heat winners Sarah Redpath, Ian Holloway and Rory Loftus (not pictured) walked away with the glory and respect of their peers as well as a bottle of wine courtesy of Aroxa team.  


Next year we shall try again, to see how the 2013 student have improved and allow our 2014 students to benchmark their initial tasting skills.



Wednesday 18 September 2013

Vintage butlers. A helping hand during Harvest

Last month I was invited by CHR Hansen and the DLR Rheinpfalz to attend the annual enology symposium held in the wine town Neustadt an der Weinstrasse, where I presented to German winemakers on UK wines and MLF.  

I was luckily enough to meet with Professor Robert Steidl from LFZ Klosternburg in Austria and listen to his presentation on yeast. One of the key points Professor Steidl raised was the importance of yeast re-hydration  in ensuring good quality inoculation and subsequent fermentation. He then introduced the Hefebutler, made by Austrian company SITT Developments. The Hefe or Yeast butler is an automated yeast re-hydration machine. Designed to prepare yeast in a controlled manner and inoculate the tank automatically when it reaches the correct point.

    

   
Yeast Butler (SITT Developments)

I would guess that almost all winemakers have experienced re-hydration & inoculations issues. My personal list includes running out of hot water, finding all cellar thermometers broken leaving you to judge temperature by feel, overflowing yeast buckets and hefting heavy buckets up to the top of tanks. 
Added to the list of problems is my personal red mist issue, which is cellarhands abandoning the yeast re-hydration process to go to lunch, leaving the poor yeast starving hungry and shivering with cold.  

SITT seem to offer a solution to these problems. From the website information the machine seems to work in the following way:
  1. Roll the machine to water supply where it automatically fills to correct level and warms to the correct temperature.
  2. Roll the machine to your juice tank and connect it.
  3. Once correct water temperature is reached, the beep tells you to add a bag of yeast. From then on it's all gravy.
  4. The butler carefully stirs the yeast, aerating and adding nutrition as required. The butler will also take juice from the tank and cool the yeast down until it is the same temperature and sugar level minimising thermal & osmotic shock.
  5. At this point the butler injects the yeast culture into the juice tank and the ferment can begin.
  6. The butler is then detached from the the juice, reconnected to the water, where it self-cleans, minimises risk of cross contamination.

It would be good to try out in a real winery situation, to see if improvements to ferment and winemaker sanity are worth the money.

Tuesday 17 September 2013

Jack Ward laboratory at Plumpton College


A tweet by  Dr Belinda Kemp an ex-Plumpton student and more recently ex-lecturer who is now senior scientist at CCOVI Brock University, led me to a recent paper about English & Welsh Winemaking.  In Hugh Clout's article, he outlines some of the important history of the local wine industry.  It makes mention of Jack Ward and the Merrydown drinks company and the important role they played in bring viticulture/oenology back to Britain after it had died out in the early 20th Century.

Fast forward to September 2013 and the Plumpton College wine department is about to expand into its new wing.  The new building has been under construction for just over a year, and will incorporate two significant spaces.  The first is the Rathfinny research winery, a new micro-vinification facility for conducting trials by students and researchers.  This new area was funded by generous donations from Sarah & Mark Driver of Rathfinny Estate, who also gets a mention in Hugh's article.



Rathfinny research winery 

The second area is a newly expanded laboratory for teaching and research, which was made possible by a donation from the Merrydown trust.  This laboratory will be named the Jack Ward laboratory to honour his contribution.



Jack Ward laboratory
Along with these new additions, the changes inspired by the construction have also allowed some additional expansion to the HE student area of the College.  So our students will soon be benefiting from a larger common room, group study rooms and enlarged computer suite.


New HE Computing suite


So the HE students will be here shortly and they will get to study in this area that links to the past with the future, which has all be made possible through the generosity of their predecessors.    

For more information on the project, as well as information how you can assist please go to the Plumpton College Wine Research Centre homepage

Monday 16 September 2013

Plumpton College gets a touch of Formula 1


Courtesy of our new Randox Monaco analyzer.



Randox Monaco Analyzer

We have had a Randox Daytona previously, but this year we are exchanging our clinical unit for the newly released food-dedicated Monaco machine.  These units are great as they allow high-quality enzyme based analysis to be done on wine samples with a minimum of fuss.

Enzyme-based analysis have been a boon for the wine industry, allowing the measurement of specific wine components without interference from other compounds present in wine.  For example many wineries measure titratable acidity, but can't tell exactly what types and quantities of acid make up this reading.  However with enzyme analysis it is possible to measure exactly how much lactic, acetic, citric, malic a wine actually has.  

They work because enzymes generally catalyze only one specific reaction, so adding that enzyme will consume all the key compound without reacting with anything else.  However that in itself would be no good unless we can also measure what the product of reaction is.  Luckily the enzyme-based reactions cause the formation of the redox  biochemical NADH (Nicotinamide adenine dinucleotide), which cause UV light to be absorbed at 340nm.  We can measure how much absorbance occurs and from this calculate how much malic acid we had to start.  

NAD+/NADH absorbance (wikimedia commons)

Traditionally this was done in laboratory by lab staff using small reagent kits and micro-pipettes, which can be expensive and fiddly to get right.

The Monaco automates this process, using tiny amounts of both sample and enzyme reagents and getting results with more precision.  Once the unit is commissioned we hope to measure the following compounds, quickly and easily.
  • Lactic acid 
  • Malic acid 
  • Acetic acid 
  • Glucose & Fructose 
  • Ammonium ions
  • Amino acids 

Sunday 15 September 2013

Busy times

What a week!

Most of my time was spent lecturing to 17 students on the Principles of Winemaking course at Plumpton College. They were a great bunch, really enthusiastic and keen to find out as much about wine in a short amount of time.  As usual there was a real mix; permutations of women, men, all ages, British, Australians, Turkish, American, Taiwanese, Danish, career changers, newly retired,  business people, consultants, a microbiologist, a chemist, MW students and grape growers.  
Principles of winemaking students


In the week that I have with them I have 20 hours of lecturers to talk through the key concepts of winemaking, which is a tough ask.  Further more I don't want to give a simple recipe to follow, but instead want to give them some tools with which they can use to approach winemaking and allow them to make their own decisions.  Its a tough process and the students need to be engaged to be able to assimilate the knowledge.  Luckily they are very keen and up for the challenge.  After I have them for lectures they are then sent to winery to do more practical activities with our practical wine making instructor Peter Morgan.  This helps cement all the theory  they have covered.
Cleaning the crusher after the afternoon processing


When not teaching, I was getting ready for the return of our undergraduate students.  Re-enrolments start this week so its always a busy time.  There are new students to meet and  prepare for teaching as wall as our returning second years to welcome back.  Though in this case the welcome back is an intensive 2 day course on Winery safety, so that they can work in the College winery and labs without endangering themselves and others.  

But lets not stop there, I also have a second group of Principles of Winemaking students in for two days, a new piece of lab equipment (new Randox Monaco analyser) to install and plenty of the usual paperwork to complete.  Can't see myself working much on PhD this week, but lets see what happens.  Time to log off and plan some teaching and assessments.  

   

   

A winemaker from Australia, Lecturer from England and PhD student from France walk into a bar...

and he orders a single glass of cold frosty Cooper pale ale.

I have three professional identities and my posts here are to help reconcile all of them together.

First I was a winemaker working in some very fun wineries.  I have been to Berri, Renmark, Sicily, Coonawarra and Abruzzo. I have made millions of litres and single barrels in permutations of white, red, rose, dessert, sparkling and fortified.


Rodea winery, Abruzzo
Katnook Estate, Coonawarra


Then I became a lecturer in winemaking at Plumpton College and again found myself keeping busy doing with lots of subjects like maths, chemistry, microbiology, lab analysis, sensory science and oenology.



Most recently I have become a PhD student at the University of Reims, where I am about to delve deep into the fields of oxidation, white wine polyphenols, grape & yeast proteins and Laccase.  I know a little about of all of these areas, but would like to dig deeper.  I hope to become fluent in this knowledge, so I don't have to return to the text book to be able converse with my peers.  

So this first post is the start of this process.