Good hygiene depends on high quality water.

A final rinse after cleaning and sanitising with low-quality water that contains bacteria, or is too hard for chemical to be effective could be putting your wine at risk when it doesn’t have to be.  By using high quality water in your winery operations, you can minimise contamination risk, without significant financial expenditure.  There are two principal considerations to take into account to assess water quality - water hardness and potability.

As wine is a potable good, it is common sense to make sure that the water used in a winery is to a potable standard.  If you are using rain water  - it is important to make sure that there is no bacteria, yeast of microbes that are persisting in your tanks as this may impact your final rinse and your overall hygiene standards.  You can treat your rainwater with filters which can dramatically improve water quality.  High quality filtered water is essential for bottling lines and is useful to protect finished wines.  Bore water should be treated with similar filtration methods so that you can maintain the highest possible hygiene standards in the winery.

Water hardness is a measure of the mineral content in water (hard water having a high mineral content).  When water hardness is being quoted, the value being talked about is the ‘total permanent hardness’ of water, which is the amount of Calcium and Magnesium sulphates in water, but is expressed as an equivalent of Calcium Carbonate (CaCO3).  

Let’s look at a practical example, say the Barossa Water System in South Australia.  The total permanent water hardness in this system sits at 148 mg/L of CaCO3.  According to the United States Geological Survey, this puts the water in the Barossa in the ‘Hard’ classification (between 121 and 180 mg/L is classified as ‘Hard’).  While water hardness is not detrimental to health, it is definitely a negative in an industrial setting.  

Firstly, the hard water is more corrosive, especially in galvanic corrosion.  So using hard water decreases the useable life of your stainless components.  Don’t forget that hard water also deposits scale on metals, which can clog up your pipes too.  More importantly, hard water also reduces the effectiveness of your cleaning and sanitising chemicals.  

Hard water has many free 2+ ions that combine with metal salts in hygiene chemicals to form soap scum.  Essentially the minerals in the water reduce the surfactant properties of your cleaning and sanitising agents.  This in turn reduces the rinsing properties of your solution.  The surfactants role in cleaning agents is to keep surface tension in solution high, which keeps insoluble molecules suspended in solution so they can be washed away.  If the reduction in surfactant properties is high enough, you will be left with deposits on your tank walls which will require further work (costing you time and money).  

To combat hard water more chemical may be required.  The use of additional chemical should be carefully considered, as there will be a flow on impact to your effluent.  If water hardness is impacting the cleaning efficacy of your chemical to an extent where deposits are being left on your surfaces, it would be detrimental to simply leave the deposits on your stainless surfaces, as this would provide an excellent breeding ground for microbes such as Brettanomyces.  

Most good industrial cleaning products should contain ingredients to counteract the effects of hard water, however if you live in a particularly ‘hard’ water area, such as our friends in the Barossa, then water softening could be a worthwhile investment.  Water softening does come at a risk of higher Sodium or Potassium deposits in your soil, as they are the two main salts used to soften water (in ion transfer softening).  However you want to treat hard water, it is worthwhile knowing what your water hardness level is, and then carefully consider the impact of treatment or additional chemical on your effluent.

By using potable water, and being aware of the hardness level of your water, you offer your cleaning chemicals the best opportunity to effectively clean your surfaces.  As the saying goes, rubbish in equals rubbish out.  So don’t start with rubbish water quality, otherwise you’ll get rubbish wine out.

---

References

Aquasafe systems (2005) Quality of Mains Water Assessed Against Water Quality Criteria, http://www.aquasafecanada.com/quality-of-mains-water-assessed-against-water-quality-criteria/, Accessed 2013-12-06

Wikipedia (2013) Hard Water, http://en.wikipedia.org/wiki/Hard_water, Accessed 2013-12-06

Is peracetic acid putting your wine at risk?

• Sanitation enables winemakers to control what their wine comes into contact with
• Peracetic acid sanitisers break down to hydrogen peroxide and acetic acid
• Acetic acid is one of the primary causes of VA

Peracetic acid smells like ants, breaks down into acetic acid and could result in your wine smelling like nail polish remover.  

The need for sanitation has never been greater - however without the right tool for the job your wine may be suffering.  Protecting your wine with a sanitiser is best practice hygiene.   However the use of sanitisers that contain peracetic acid can result in an inadvertent acetic acid addition - increasing the risk of volatile acidity (VA).

Sanitation is important.   We strongly recommend that every winery implements high quality sanitation protocols.  Good hygiene through a fully built cleaning agent and a sanitiser (that won’t taint wine) will reduce the risk of unwanted bacteria yeast and microbes taking hold in your wine.  Ultimately it protects your investment.  Chemical products used in the cellar for cleaning and sanitation that taint wine increase the likelihood of wine spoilage through human error.

The wine industry needs skilled labour to produce wine.  This reliance on staff means there is an inherent risk of mishaps.  Mistakes are made - especially when workers become tired during busy periods like vintage.  If peracetic acid sanitisers come into contact with wine the net result is an addition of acetic acid to your wine.  This poses a significant problem.

Sanitation Guide

Adding acetic acid to any wine is concerning. Basic organic chemistry tells us that peracetic acid will break down into hydrogen peroxide and acetic acid (Bird, 2010 p216).  The hydrogen peroxide will form water and oxygen.  The acetic acid is something that winemakers are almost universally trying to prevent coming into contact with their wine.  This is because of the risk of taint through VA.  

One of the primary causes of VA is acetic acid (the acid of vinegar).   Although acetic acid is a natural component of wine, an oversupply of acetic acid can lead to wine spoilage (Bird, 2010 p255).  If a wine does have acetic acid issues this can lead to further work in filtration, reverse osmosis or having to isolate and blend the affected wine.  This takes time and further increases the cost input into finished wine. 

The AWRI states in their report “Wine Bacteria - Friend or Foes”  that there is a high risk of spoilage caused by acetic acid bacteria during prolonged barrel maturation and poor management (of acetic acid) during bottling and storage of red wine (AWRI Wine Industry Journal, 2009).  Acetic acid bacteria are also able to survive in ethanol and sugar rich environments (Bartowsky and Henschke, 2008). The use of a sanitiser during these periods reduces the risk of further unwanted bacteria, yeast and microbes coming into contact with wine.  However peracetic acid based sanitisers increase the risk of inadvertently making an acetic acid addition to your wine - especially if a single pass rinse is not completed properly.

Acetic acid bacteria have been shown to contribute to volatile acidity in wine must and the production of acetic acid can contribute to sluggish or stuck ferments also (Du Toit and Lambrechts, 2002). Peracetic acid presents a risk that can be avoided easily through the use of chemicals that will not taint.  This eliminates the risk of human error in the cellar and gives winemakers some assurance that spoilage through VA will not be caused through chemicals used on site.

We don’t believe products that can taint wine should be utilised in wine production.  As such we would recommend any of our sanitisers (which can be viewed here), Destainex or Destainex LF  will provide effective sanitising and will not taint your wine.  Give them a go - your wine will thank you for it!

---

References

Bartowsky, E.J. and Henschke, P.A. (2008) "ACETIC ACID BACTERIA SPOILAGE OF BOTTLED RED WINE - A REVIEW",International Journal of Food Microbiology 125, 60-70.

Bird D, (2010), “UNDERSTANDING WINE TECHNOLOGY” third edition, p72, p138, p139

Du Toit, W.J. et al (2002) "THE ENUMERATION AND IDENTIFICATION OF ACETIC ACID BACTERIA FROM SOUTH AFRICAN RED WINE FERMENTATION'", In International Journal of Food Microbiology, vol. 74, 2002, p. 57– 64.

Eveline J. Bartowsky,et al (2009), “WINE BACTERIA - FRIEND OF FOES” - AWRI Report, March/April 2009, Vol 24 NO 2, Wine Industry Journal

Kantor et al (2013)“LACTIC ACID AND ACETIC ACID BACTERIA ISOLATED FROM RED WINE”, Journal of Microbiology, Biotechnology and Food Sciences (special edition) pp1704-1715

Links

http://www.newworldwinemaker.com/pdf/AWRI_report_wine_bacteria_friend_or_foe.pdf

http://www.jmbfs.org/wp-content/uploads/2013/06/69_jmbs_kantor_fbp_m.pdf

Wine opinion: why some aromas are better left out of the bouquet

"Unscrupulous winemakers still don't clean their equipment properly, and use bad fruit. So, as the saying goes, 'rubbish in, rubbish out.' But this wine still has to be sold."

You can read the whole article here.  The point we like to take out of this is that while some bacteria and microbes are beneficial to your wine, others are not.  We know, it's not revolutionary stuff, but the point of cleaning and hygiene is to control for the bad stuff, whilst still maintaining the good stuff.

Advancing the frontline against Brett

In the fight against Brett, winemakers need to have access to the best technology possible.  For many years now, the Australian Wine Research Institute (AWRI) has been developing cutting edge technology, and engaging in 'on the ground' communications work to bring this technology to Australian producers.  

Recent advances in genome sequencing techniques has allowed the AWRI to take a closer look at Brett and to determine what causes it's sulphur resistance, and what can be done about it in a targeted manner.  Check out the article"Advancing the frontline against Brett" - it's well worth a read.  

For our two cents, at this current stage, your best bet to help control Brett growth is to have a thorough hygiene regime in place.  This will always be the case, not only for the fight against Brett, but also against all unwanted microbes in your wine.  

The scourge of Brettanomyces and the need for sanitising.

Over the past few years Brettanomyces or Dekkera (Brett for short) have been spreading rapidly throughout wineries in Australia causing much unwanted wine taint, specifically in the form of volatile phenols or ‘sweaty leather’. Brett yeasts are a natural component of the winemaking process, which makes it almost impossible to eliminate completely and unsurprisingly they find themselves in winery air, on cellar walls, drains, pumps, transfer lines and other pieces of equipment.  The two most important stages for Brett contamination in winemaking occur during malolatic fermentation and ageing in used barrels. Brett’s slow growing characteristics are best suited to the conditions created after alcoholic fermentation is completed and where the surfaces are not cleaned and sanitised correctly, leaving residual sugars and allowing Brett to proliferate.

The real issue here is how to combat Brett proliferation in your winery.  A report in the South African Journal of Enology and Viticulture outline the five key areas for the spread of Brett, which are;

1. Recent trends in some winemaking styles - such as wines with higher pH values and residual sugar;
2. Trends in winemaking practices - decreased use of filtration and SO2;
3. General poor cellar hygiene along with improper cleaning and sanitisation of barrels - a critical source of Brettcontamination of wine;
4. The spread of Brett between wineries and regions due to the use of contaminated barrels which are traded in the second hand barrel market; and
5. Importation of Brett contaminated wine from other affected wineries. 

The first two points are winemaking practices, and as we are hygiene specialists not winemakers, we’ll leave those decisions up to the experts and enjoy the end result! The last two points are about good winery management.  That is making sure you know what you are putting into your cellar and where you are getting your produce from, that’s just good practice.  Knowing when Brett infected products or wine is in your winery will enable to you to take steps to manage their spread, and limit any damage that may occur.  There are many different ways to manage Brett in your wines once they are there, some of which are outlined in this Wine Monthly article, but we believe that prevention is better than a cure and that brings us to point 3 - poor hygiene.  As dull as it may sound, it’s serious business and it can cost you dearly if you don’t take it seriously. 

Research into Brett has shown that it is able to form significant biofilms on what appear to be clean surfaces, and these biofilms are a major source of Brett propagation throughout a winery.  The formation and adherence of Brett has been shown to increase with increasing pH of wine, and sulphur dioxide is known to slow down the rate of Brett growth in solution (which is why it is so commonly used in modern winemaking).  A good summary of biofilms and effect of cleaning and sanitising can be found here.  However these are merely control solutions after infestation, rather than a method to eliminate harmful microbes from your wines.  Another source of Brett contamination is in oak barrels.  A 2013 study by Guzzon, Nardin, Micheletti, Nicolini and Larcher outlined the use of ozone as ‘a highly effective sanitising agent without interfering with the profile of the phenolic substances extracted from oak’.   

When we talk about hygiene, what we are really talking about is your hygiene procedure, which includes all aspects from cleaning, sanitation and scheduling.  It’s important to have a thorough hygiene procedure in your winery to limit the spread of all microorganisms, not just Brett.  Cleaning is a very important part of any winemaking process, however a clean surface is deceptive as it can still harbour microorganisms such as Brett that can taint your wine if left unattended.  This is where sanitisation is most important and is something that needs to be addressed in a serious and systematic way so that you can ensure the quality of your wine.  Think of sanitation like insurance for your wine.  If you do it properly, then you can be safe knowing that there won’t be any hidden surprises along the way to achieving your final product.  Just remember, sanitation alone will not cure a Brett infestation, as sanitation will not destroy the biofilms that Brettutilises to grow, but using the right cleaning agent, followed by correct sanitation will provide you with the best possible counter-attack to Brett infestations.  The last and probably most important step is to develop a hygiene procedure within your winery, and then stick to it.  If you take hygiene seriously, then you shouldn’t have to spend much time worrying about the scourge of Brett in your winery, which means you can spend more time making great wine!

References

Oelofse, A, Pretorius, IS & du Toit, M 2008, ‘Significance of Brettanomyces and Dekkera during Winemaking: A Synoptic Review’, South African Journal of Enology and Viticulture, vol. 29, no. 2, pp. 128-144

Barata, A, Laureano, P, D’Antuono, ID, Martorell, P, Stender, H, Malfeito-Ferreira, M, Querol, A & Loureiro, V 2013 ‘Enumeration and Identification of 4-Ethylphenol Producing Yeasts Recovered from the Wood of Wine Ageing Barriques after Different Sanitation Treatments’, Journal of Food Research, vol. 2, no. 1, pp. 140-149

Patterson, T 2012, There’s No Subsitute for SO2 (Yet), Wines and Vines, http://www.winesandvines.com/template.cfm?section=columns_article&content=103719&columns_id=24

Joseph, L, Kumar, G, Su, E & Bisson, L 2007 ‘Adhesion and Biofilm Production by Wine Isolates of Brettanomycesbruxellensis’, American Journal of Enology and Viticulture, September 2007, vol. 58, no. 3, pp. 373-378

Guzzon, R, Nardin, T, Micheletti, O, Nicolini, G, & Larcher, R 2013 ‘Antimicrobial activity of ozone.  Effectiveness against the main wine spoilage microorganisms and evaluation of impact on simple phenols in wine’, Australian Journal of Grape and Wine Research, June 2013, vol. 19, no. 2, pp. 180-188

It’s time we stopped using commodity caustic in Australia

Yes it’s cheap and it’s ubiquitous, but it may be doing damage to your wine and equipment, but let’s first look at the pros. Caustic is very good at quickly removing heavy deposits of wine solids with tartar whilst its pH is in the range 10-14 and used with potable water in ambient temperature range of 20-40°C.  These few benefits are the main reasons why it has become so widely used throughout the global wine industry.   

As caustic is a sodium product, it is potentially environmentally degrading (high sodium effluent can cause sodic soils), corrosive to most contact surfaces, creates high HR risk in use (burns to skin and eyes) and is not as an effective cleaning agent as you might think.  In addition to that, think of all of the extra paperwork and cartage cost required in transporting, on-site handling and storage; on site HR supervision; as well as the safety equipment required and maintenance for its use.

The pH differential between caustic and wine is 14 to 3.5 respectively, and the salt, whilst effective in decolourising and dissolving the organic soil, denatures and chars it at the same time (evidenced by red wine colour converting to a charcoal). At the same time, as a common salt derivative it increases surface tension which reduces likelihood of the removal of the protein.  When cleaning with caustic, often biofilm/protein char presents on surfaces after the process which requires large amounts of hot water and a mechanical action (high pressure pump spray) with task specific cleaning agents or often scrubbing in smaller tanks with only water (or a safe-to-use chemical) to simply to remove this film.  

With all of this there is still no guarantee that you have eliminated layered protein char-stain from your stainless equipment, most particularly in large stainless steel tanks. It has become common practice to rinse with a low dose aqueous citric acid after the caustic cleaning process to neutralize any residual sodium salt and reduce Ca/Mg scale.  This process will not remove the charred biofilm, (as you may well have already experience), and this biofilm is the perfect breeding ground for Brettanomyces to flourish within your tanks. 

In an attempt to fix this ‘filming’ problem where there are heavy stains, rather than re-cleaning equipment with more reliable cleaning products, it has become common practice in some wineries to increase the concentration of the caustic solution and increase ‘cleaning in place’ (CIP) circulation time.  What you need to understand and what we are trying to stress is, simply putting more caustic in and leaving it there for longer won’t remove the bio-film but may in-fact, exacerbate it.  If you increase the concentration of caustic in solution, you run the risk of premature ageing of your assets (e.g. pitting in the stainless surfaces of your tanks), and you increase the danger for your employees having to mix a dangerous good in higher proportions, which can cause severe burns if it comes in contact with skin or eyes.  Caustic is strongly reactive with aluminium and can cause degradation of glass surfaces, so not only do you have to be careful about where and how you store it, but also how you use it. 

So let’s look at some more chemistry.  When a quantity of caustic soda granules (pearl) comes into contact with a small volume of water it creates a strong exothermic reaction which can be dangerous to users as it can cause high pH vapour, which then comes into contact with the skin, or worse, the eyes.  If you are using hot water in your cleaning process (which we would strongly recommend), a much more volatile and dangerous ‘spitting’ reaction occurs upon contact of caustic with water.  The highly alkali pH of caustic solution can lead to blindness if it comes into contact with your eyes.  So the real question is, why risk this happening to your trained cellar staff, or even to yourself if you are the all-in-one person in a small/micro winery?

Yes, caustic is cheap.  However, when a staff member is injured due to using a dangerous good, workplace injury claims aren’t cheap; and wasting wine isn’t cheap when your wine tanks and lines aren’t really satisfactorily and they become infected with unwanted microbes.  It’s simply not worth it.  It’s time to use your grey matter, look across the spectrum and compare the greater negatives with the few positives for commodity caustic soda.  The alternatives now available are far more effective at cleaning your surfaces, safer for you and your wine and require less effort to get the job done correctly the first time - but that’s a conversation for another time.  

If you have any questions about caustic alternatives, then get in touch, because it is time to stop using caustic, it’s time to start cleaning smarter, safer and cleaner. 

Caustic ineffective against mature Biofilms

A recent article in Food Quality News demonstrated that mature salmonella biofilms were not able to be removed by sodium hypochlorite, sodium hydroxide and benzalkonium.

This has a direct implication on wine production.  Biofilms caused by sodium hydroxide (or chemical filming caused by sodium metasilicate) can leave an environment where yeast, bacteria and microbes can persist on stainless steel and potentially taint your wine.

Read more here:

http://www.foodqualitynews.com/Innovation/Salmonella-biofilms-show-disinfectant-resistance

http://www.airdchemistry.com/news-item/Biofilms---the-reason-you-should-care-about-protein-stains-October-18-2013/

http://www.airdchemistry.com/news-item/Itas-time-we-stopped-using-commodity-caustic-in-Australia-October-9-2013/

If you have any questions about caustic alternatives or better sanitation, then get in touch, because it's time to stop using caustic and start cleaning smarter, safer and cleaner.