Heat and Cold Stability Analysis
Our stability analyses are designed to give you confidence that your wines won’t produce a haze or precipitate tartrates in the bottle
Heat Stability Check
Wines subjected to elevated temperatures may form an undesirable haze due to protein instability. Prior to bottling, our Heat Stability Check analysis allows you to quantitatively assess the potential for haze formation.
The Process
We first clarify the wine by filtering it through a sterile membrane filter, ensuring the initial turbidity is below 1 NTU. The sample is then exposed to elevated temperatures in a controlled heat bath. After allowing the sample to cool to room temperature, we read the final NTUs – any increase in turbidity can be associated with haze formation from protein instability.
Interpreting the Results
- A final turbidity result less than 1 NTU is considered heat stable
- Results between 1-2 NTUs are considered at risk for haze formation – steps to further stabilize the wine may be necessary
- Results greater than 2 NTUs indicate the wine is not protein stable. These wines may benefit from a full Bentonite Trial.
Cold Stability Check
Wines subjected to cold temperatures run the risk of precipitating
tartrate crystals, which are often perceived as undesirable or even
hazardous by consumers.
Our Cold Stability Check analysis quantitatively assesses the risk of tartrate precipitation.
The Process
The sample is first clarified by filtration, then chilled in a
controlled environment while the conductivity is measured. A
decrease in conductivity is associated with an increase in tartrate
formation/precipitation.
Interpreting the Results
- A change in conductivity less than 3% is considered stable
- Change in conductivity between 3-5% is considered at risk for tartrate formation. It may be necessary to take additional steps to ensure your wine is stable before bottling.
- A change greater than 5% indicates tartrate precipitation is likely. Further action to cold stabilize the wine is recommended.
Stability Product Trials
Bentonite Trials
Adding too little bentonite can leave your wine susceptible to protein instability, while adding too much could risk stripping the wine. Running a Bentonite Trial can help determine the right bentonite addition rate – one that will stabilize with minimum impact on wine quality.
- For these trials, we’ll use your bentonite product at the addition rates you request
- The bentonite is added to the wine at the end of the day, fully dispersed, and allowed to settle overnight. In the morning we follow the Heat Stability Check procedure to assess the effect each bentonite addition rate had on the wine.
Cold Stability Trials
In the past, winemakers would cold stabilize their wines prior to bottling by holding the wine at low temperatures for an extended period of time, effectively forcing tartrates to precipitate out of solution in the tank rather than the bottle. Now there are products that chemically disrupt the tartrate crystal formation process. Our Cold Stability Trials are designed to test the efficacy of these products while also assessing potential risk of protein and colloid instability.
Custom Bench Trials
Modern winemakers have access to a large array of enological additives that affect color, mouthfeel, and other sensory characteristics of wine. Before making production-scale additions, our Custom Bench Trials allow you to qualitatively and quantitatively assess sensory impact in a precise and controlled environment.