Chapter 14

Winery Cleaning and Sanitation

Winery Cleaning and Sanitizing Process

Cleaning is the process of removing organic and inorganic contaminants to a level of insignificance. Cleaning agents are designed to facilitate this process by breaking down, solubilizing, and dispersing contaminants into water, so the contaminants can be washed away. Sanitation is the process of eradicating living microorganisms down to an acceptable level and which has no adverse effects on winemaking. Bear in mind that a given washing or sanitizing agent may not be compatible with every type of material in winemaking equipment. An agent that is suitable for use with stainless steel, for example, may not be suitable with food-grade plastics and rubbers, and other types of materials, or vice versa.

What Needs to be Cleaned and Sanitized

Floors, walls, ceilings, drains, destemmers, fermentors, tanks, barrels, hoses, hoppers, crushers, presses, fittings, and fixtures, buckets, plungers, sampling devices and anything that makes contact with wine should be cleaned before and/or after use. Floors and walls of cellar areas should be rigorously cleaned as needed to remove ingrained dirt, color material and biofilms (a slimy material containing microbes embedded in polysaccharides) that will prevent the effectiveness of daily cleaning operations.

Five-Step Cleaning and Sanitation Process

To be effective in removing organic and inorganic contaminants and reducing the number of pathogens a five-step cleaning and sanitizing framework is usually employed by wineries.

Pre-Rinse

After using a piece of equipment and while any organic material is still wet, rinse the equipment to dislodge the bulk of the material, which may otherwise interfere with (bind up) chemical detergents applied during cleaning. This can be accomplished either manually or by automated cleaning systems that apply low volumes of warm (38-43°C, 100-109°F) water at high pressure.

Cleaning Cycle

Once visible debris and film has been removed, detergents are used to solubilize any remaining deposits. Typical cleaning detergents include water (hot and cold), sodium or potassium hydroxide (caustics), carbonates or percarbonates, trisodium phosphate, and physical cleaning actions such as scrubbing, brushing or high-pressure spraying. There are also a range of proprietary blends which may include surfactants (detergents or wetting agents to lift dirt from surfaces) and sequestrants (metal chelating agents), which are important when using hard water.

Post-Rinse

Once the cleaning cycle using detergents is completed, equipment surfaces should be thoroughly rinsed to remove residual chemicals and debris. A detergent residue can decrease the efficacy of the following sanitation step or, in a worst-case scenario, contaminate the wine. Although hot or cold water is commonly used for this initial rinse, a mild acid (e.g., citric) rinse will neutralize alkaline detergent residues.

Sanitizing Cycle

Once deposits and debris are removed and surfaces are visibly clean, the equipment can then be sanitized. An appropriate sanitizer will greatly reduce the microorganism load within the vessel.

Final Rinse

Once the sanitation process has been completed, surfaces are rinsed to remove residual sanitizer and drained. For instance, tank and hose sanitation is typically followed with a citric acid rinse to neutralize any residual alkali. If the municipal water contains too much chlorine, an inexpensive carbon water filter can be used to remove the chlorine.

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