Step #0: Cleaning & Sanitation

Most faults in wine quality are a consequence of juice or wine coming in contact with dirt and spoilage microbes in the air and on contact surfaces (vessels, piping, tools, etc.). Therefore we spend a significant amount of energy and time keeping the winery and cellar clean and sanitized. In this context, “cleaning” refers to the physical removal of organic and inorganic soils, “sanitation” means inactivating 99.9999% of spoilage microbes.

On this page, we describe:

  • The five steps of cleaning

  • The equipment we use for cleaning, and

 

The five steps of cleaning

  1. In general, the cleaning and sanitation process has five steps:

  2. Warm water rinse to loosen up and remove debris

  3. Cleaning cycle

  4. Water rinse to remove cleaner residue and loosened debris

  5. Sanitizing cycle

  6. Cold water rinse, if necessary, to remove sanitizer.

We clean equipment each end of the day after it has been utilized (steps 1-3), and we clean and sanitize all equipment when it is taken out of storage before we use it. This page describes how we clean all harvesting and winery equipment; a particular page in the Cellar section explains how we clean barrels.

 

Water power-washes and rinses

We distinguish between three levels of purity in water used for cleaning, rinsing, and sanitation:

  • Regular city water contains a fair amount of chlorine and should not be used on surfaces that come in contact with juice or wine. Chlorine can result in chemical reactions resulting in TCA, which is known as cork taint. We use regular city water only to power-wash floors

  • Softened water: we dechlorinate all our city water used in the winery with a Kinetico 4040 salt-based, regenerative ion-exchange system (see www.Kinetico.com)

  • Distilled or purified water

We use softened cold water in power washers to remove sugars and proteins, and we use softened hot water in power washers to remove tartrate buildups.

 

Cleaning cycle

We distinguish between three types of cleaners

  • Caustic: NaOH, KOH

  • Non-caustic / alkaline-based: sodium carbonate, potassium percarbonate, trisodium phosphate (TSP). We need to use citric acid to rinse after to neutralize alkaline residues.

  • Acid Cleaners: Phosphoric / Nitric acid based

We use the following chemical solutions:

  • Potassium Hydroxide / Caustic Potash (KOH)

  • Sodium Percarbonate Na2H3CO, Dissolved in water, sodium percarbonate yields a mixture of hydrogen peroxide (which eventually decomposes to water and oxygen, sodium cations Na+, and carbonate CO2

  • Trisodium Phosphate (TSP) Na3PO4

Note, biofilms are resistant to many chemical cleaners, so casual rinsing or washing is not sufficient.  It is best to remove the films by scrubbing, brushing, or high-pressure washers.

  • We use brushes to clean stainless steel surfaces

  • Use scrubbing foam balls to clean the inside of hoses

  • We circulate cleaning solutions through hoses with electrical pumps

We have used ultrasonic baths (generally used for jewelry) in the past but found maintaining the equipment cumbersome.

 

Sanitizing cycle

There is a wide choice of chemicals for use in the sanitizing cycle:

  • Potassium-Metabisulfite (KMBS) , citric acid

  • Chloride (CI) - based compounds

  • Iodine (I) - based compounds

  • Sodium dioxide (SO3) solutions; need to be acidified to pH~3 and are corrosive

  • Peracetic Acid (CH3CO3H) is also corrosive

  • Star San: proprietary formulation including phosphoric acid and surfactants. No rinse is necessary and should be used at a dilution of 0.15% or 1.5 mL per L.

  • Food-grade Ethanol 70% is suitable for sanitizing punchdown tools, pipettes just before use

Our go-to sanitizing chemicals are Citric Acid, KMBS, Star San, and Ethanol, which we keep handy in spray bottles. When we clean oak barrels, containers with hard-to-clean crevices, or large equipment, we use ozone dissolved in water or as a gas or superheated steam

Equipment

Power washer

We use a regular gas-powered pressure washer for general cleaning of floors, walls, and general equipment.

 

Electric power washer with superheated steam

We use an electric power washer with a diesel-heated steam boiler to wash and sanitize large equipment (destemmers, sorting table, presses, tanks, etc.), especially after harvest. The Delco DH2305 Electric power washer we use (https://manualzz.com/doc/24175308/delco-dh2305%E2%80%9Cdirect-drive%E2%80%9Dseries) is no longer available. It is beneficial for cleaning/washing off tartar films on crushing equipment and general clean-up. It is not 100% stainless steel, so residual rust particles can potentially be harmful to wine if not rinsed off subsequently.



Electric steam power washer:

We use a Swash Deluxe Steam Generator from Electrosteam we bought from ARS Enterprises in Calistoga, CA (https://www.electrosteam.com/applications/winery-steam/).  It is not a pressure washer like the Delco mentioned above; it provides superheated steam and is built using stainless steel throughout. So its primary use is for sanitizing oak barrels (see Cellar section) and floors, walls, large winery equipment, etc.




Handheld steamer

We use a PurSteam handheld electrical steamer purchased from Amazon for spot sanitizing valves and other small items with crevices. Any low-cost household steamer does an excellent job.

 

 

Ozone generator

We use an ozone generator from A2Z Ozone Inc ( it is currently sold at Walmart) for sanitizing rooms and oak barrels after being washed and steamed. We also use it for deodorizing and sanitizing entire rooms.

 

Auxiliary pump

We use a Sureflow diaphragm pump assembly purchased from VA Filtration in Napa, CA (www.vafiltration.com ) designed to clean the Sweetspotter (see Filtering – Reverse Osmosis in the Cellar section). For cleaning hoses, the pump circulates cleaning, rinsing, or sanitation solutions from a bucket through the hose back to the bucket.

 

Scrubbing ball

We use scrubbing sponge balls to clean and sanitize hoses. Scrubbing sponge balls come in various sizes and types (soft, semisoft, and hard). We insert them into hoses filled with cleaning solutions and drive them through with a pump.

Barrel washer

We built a special washer to wash, steam, and ozone oak barrels, because we could not find equipment that recirculates the washing fluid (and thus minimizes water usage) and fits into our small space. It is basically a wash-basin on wheels with an electric pump that feeds water to a spray-ball inside the barrel sitting on rollers above the basin. See Cellar Section for details on how it is used in the racking process.

 

 

 

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Last updated: November 30, 2021