ETS Laboratories - Juice Panel

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Juice Panel - Enhanced

NAME	UNITS	TECHNIQUE	METHOD	ACCREDITATION

Acetic acid bacteria	cells/mL	Scorpions™
The three genera of acetic acid bacteria detected are Acetobacter, Gluconobacter and Gluconacetobacter. Acetic acid bacteria are commonly associated with grapes and the winery environment. They are often introduced to the winery by coming in on contaminated fruit from the vineyard. Acetobacter can oxidize ethanol to produce acetic acid in the presence of oxygen. These organisms are often associated with elevated volatile acidity in wines and can rapidly spoil wine exposed to air during barrel aging.

Alpha-Amino Compounds (NOPA)	mg/L	FTIR	ETS Laboratories
Alpha Amino Nitrogen, also referred to as Nitrogen by OPA, or NOPA, measures the amount of primary amino acids available for use by yeast during fermentation. NOPA is often measured in conjunction with ammonia to obtain the Yeast Assimilable Nitrogen (YAN).

Ammonia	mg/L	FTIR	ETS Laboratories
Ammonia is a readily available form of nitrogen for yeast nutrition. Ammonia is often measured in conjunction with NOPA to obtain the Yeast Assimilable Nitrogen (YAN).

Brix	degrees	FTIR	ETS Laboratories
°Brix is a measurement of the apparent concentration of sugar. It is commonly used for grape juice and must and is expressed as a percentage by weight (% w/w). One degree Brix is defined as 1 gram of sucrose in 100 grams of aqueous solution. When the solution contains dissolved solids other than pure sucrose, as the case for grape juice and must, the °Brix is only an approximation of dissolved sugar.

Glucose + Fructose	g/L	FTIR	ETS Laboratories
Glucose and Fructose are natural compounds produced by vines during photosynthesis. In grape juice, Glucose + Fructose measures the combined concentrations of the primary two sugars present that are consumed by yeast. This value can provide an estimate of potential alcohol concentration after fermentation.

Hanseniaspora uvarum	cells/mL	Scorpions™
Hanseniaspora is a wild apiculate yeast that is often present at high levels on incoming fruit. Hanseniaspora can initiate fermentation in the must and produce high levels of volatile acids, including acetic acid and ethyl acetate. These wild yeast can rapidly deplete YAN from the must. Population levels usually decline as alcohol concentration reaches 3-5%.

L-Malic Acid	g/L	FTIR	ETS Laboratories
One of the major organic acids found naturally in grapes, L-malic acid contributes sharp green flavors to wine, similar to a sour apple. Malic acid concentration is an important component of the calculations necessary to make acid adjustments to must. This test is also useful for monitoring malolactic fermentation during which malic acid is converted enzymatically by lactic acid bacteria to lactic acid.

pH		Manual
The measure of a solution’s acidity, or hydrogen ion concentration, pH is a critical constituent of wine. pH can affect microbial activity, tartrate solubility, the interaction of phenolic compounds, and the determination of molecular SO₂. Solutions with lower pH values (<7) are acidic, while those with higher pH values (>7) are basic. pH is measured on a logarithmic scale, hence a wine with a pH of 3.0 is 10 times more acidic than a wine with a pH of 4.0.

Potassium	mg/L	FTIR	ETS Laboratories
Potassium is found in grapes and wine and increases as the berries mature. Potassium is also found in certain chemical additions, such as potassium metabisulfite. Final concentrations in wine depend on addition rates of potassium containing compounds, as well as the amount of extraction from berries through pressing and maceration.

Tartaric Acid	g/L	FTIR	ETS Laboratories
Typically the most prevalent organic acid found naturally in grapes, tartaric acid is commonly used to adjust the acid balance of must and wine.

Titratable Acidity (TA)	g/L	FTIR	ETS Laboratories
Titratable acidity (TA) measures total available hydrogen ions in solution. This measurement includes both the free hydrogen ions and the undissociated hydrogen ions from acids that can be neutralized by sodium hydroxide. Although generally considered a simple parameter, titratable acidity is actually a reflection of complex interactions between the hydrogen ions, organic acids, organic acid-salts, and cations in solution. Results of this test are reported in terms of the predominant acid in grape, Tartaric Acid, which is the standard reporting convention for TA in the United States.

Yeast Assimilable Nitrogen (YAN)	mg/L (as N)	Calculation
Yeast Assimilable Nitrogen (YAN) is a measure of the total nitrogen including alpha amino nitrogen (NOPA) and ammonia (NH₃). Knowledge of available nitrogen is essential for effective fermentation management and may decrease the likelihood of problems such as stuck fermentations or excessive sulfide production. YAN is calculated from Ammonia and Alpha-Amino Compounds (NOPA).



	The Juice Panel is the primary tool for production monitoring, and includes information used to assess fruit maturity, acid balance, and nutritional content. By providing a thorough analytical picture of grape and must composition this panel allows winemakers to develop an appropriate strategy for their desired winemaking style. Also included is the new Scorpions™ Panel designed to provide early detection of the microorganisms that can produce elevated volatile acidity levels prior to and in the early stages of fermentation. With this additional information, winemakers will be alerted to potential problem juices containing yeast and bacteria from the vineyard and can adjust cold soak and other strategies to minimize early volatile acidity formation. This panel offers a savings of $114.00 over the components priced individually. For more information regarding the Enhanced Juice Panel click here.

MINIMUM VOLUME	CONTAINER TYPE	OTHER Many clients boil or freeze juice samples to stabilize them prior to shipment. Samples submitted for Scorpions™ Panels can not be boiled or frozen as this will kill cells, resulting in inaccurate results. When submitting samples for the Enhanced Juice Panel, please provide two 60 mL tubes per sample, one for the juice chemistry analysis and one for the Scorpions™ VA producer Panel. If you choose to boil or freeze one of the tubes, please indicate on the label that the tube has been treated to stabilize for transport. The tube provided for the Scorpions™ Panel analysis should be filled half way, and shipped on ice or cold packs.

60 mL	Plastic Container	Other Sample Requirements Click Here for Details

- Grape Juice

NUMBER OF SAMPLES SUBMITTED We achieve economies of scale here at ETS based on the volume of samples processed at a given time. As a consequence we are pleased to pass these savings on to our customers, offering discounts for multiple sample submissions. These discounts apply only to samples submitted at the same time.	1	2-10	11+

Fee Per Sample	$154.00	$144.00	$138.00