WSU winery tour

Destemer and crusher, barrels and tanks

Mechanical filter

Small mechanical filter

Fermentation tanks in the new WSU winery

Old WSU Prosser winery
DR. Halbertson explaining how the bladder press works.

Bladder press

Stainless Steel Fermentation tank

Stainless steel storage tanks for white wine and experiments.

Jared posing in front of the fermentation tanks.

Top down press

Continuous filter, does not need to stop because the filter medium does not clog.

The Basics in Grape and WIne Chemistry

My brother and I went to Prosser and enjoyed a day learning about the basics in wine and grape chemistry. We visited the Washington State University Extension campus to learn and get some hands on experience in the tests used to measure various components of grapes and wines used in the winemaking process. These components included: Sugars, acids, ethanol, and SO2. We completed the following tests:

Brix through use of the refractometer, densitometer, hydrometer, and rebeline methods.

Above is a PH meter, we used this to measure the PH in the grape juice, we coupled this with the titrating process to determine titratable accidity.
This device is the refractometer used to measure the Brix in the grape juice. It gets confused when you are testing wine because alcohol messes with the results.

This glass bobber is a hydrometer and tests brix using the buoyancy of the liquid.
This device is the Anton Bar densitometer, it is the easiest and most accurate way to test for Brix.
Here we have an ebelliometer which measures alcohol content of wine.
This device was used to airate and oxidate the free SO2 out of the sample wine.

The above image is an example of paper chromatography similar to the ones we observed on our trip. This image is from the www.travessiawineblog.com website. This image showl ML fermentation is complete on 4 of the wines on the left but not complete on the 4 wines on the right.

Acids through pH, titratable acidity, paper chromatography.

Ethanol using the ebulliometer

Free and total Sulfur dioxide through aeration/oxidation

The course was taught by James F. Harbertson jfharbertson@wsu.edu


Resources:
CAWGG California association of wine grape growers
WAWGG Washington association of wine grape growers
winebusiness.com
Vitis journal
Australian tech conference

Instrument resources:
Fisher scientific
VWR
Hanna Instruments

Best lab book available:
Techniques for Chemical Analysis and Quality Monitoring During Wine Making by Patrick Iland

Other good books include:












Handbook of Enology vol. 1 and 2 by P. Ribereau-Gayon















Magazines Wine business monthly
wines and vines

People to know in the industry:

Grandall Grahm Bonny Doon www.bonnydoonvineyard.com/
Professor Markus Keller, PhD. Viticulture at WSU.
Katie Perry at Tildio www.tildio.com

Sanitizer used at WSU Winery:
Poroxiclean

Maximizing Malolactic Fermentation Seminar

MLF SEMINAR

At the Novelty Hill Januik Winery in Woodinville Washington on July 1st 2009 I attended the Maximizing Malolactic Fermentation for wine quality and style seminar presented by Dr. Sibylle krieger-Weber and Dr. Thomas Henrick-Kling. The purpose of the seminar was to understand MLF management and how various fermentation factors effect the ML process including

PH
Alcohol
SO2
Temperature
Pesticide residue
Polyphenol content
enological tannins

An important factor is the timing of inoculation how to promote or eliminate various compounds within the wine including acetaldehyde and diacetyl.

Some of the highlights are outlined below:

Oenococcus oeni is the preferred bacterial culture to use as an ML starter culture because it is acid tolerant to below pH 3.5 and tolerant to ethanol up to 14%. It also has no flavor defects.

Important factors in Malolactic Fermentation:

ML is limited by

pH - less than pH3.2
SO2 - Free sulfur dioxide concentrations above 10 mg/L
Total sulfur dioxide concentrations above 30 mg/L
Temperature - Low
nutrients
bacteriorphange
micorbial antagonism
spray residue
polyphenols

Yeast produces SO2 and SO2 will stop MLF. For co-inoculation of yeast and ML use a yeast that doesn't produce too much SO2. Lalvin W27, W46 and W15 will allow spontaneous fermentation 10-20 days after completion of primary fermentation.

The basic message from this seminar that I got was to buy Oenococcus oeni bacteria for the best results for ML fermentation, control the environmental conditions listed above, and use nutrient additives recommended by Lallemand to ensure effective MLF. Avoid spontaneous ML due to the formation of brett and other off flavor causing compounds.

Also there was a section of Biogenic amines.

Biogenic Amines originate from the metabolism of living cells from animals, vegetables and microbes.
They are present in many different foods: Fermented sausages Fermented fish, cheese, fermented olives, chocolate, tomatoes, strawberries, nuts, and wines.
The main compounds are : Histamine, Tyramine, Putrescine and Cadaverine.

Various free amino acids will create biogenic amines.

Role of Biogenic amines in human health

Histamine in low doses: contraction of muscle fibers, stimulation of neurons, activation of the gastric secretion, reaction to allergies

Histamine in High doses: Migraines, fever, some sensitive individuals may react with the formation of cancerogenous nitrosoamines.

The degradation of Biogenic Amines removes these from the body. This happens either by Monoamine Oxidases or diamine oxidases this process is inhibited by alcohol. This will give you headaches and a hangover after drinking these biogenic amines and not being able to remove them because of the alcohol in the wine. To ensure your body can degrade these biogenic amines in an effective manner take Vitamin B6 prior to consumption of the wine. Biogenic amines are also found in beer but in much less concentration 20-50 mg/kg vs up to 3,800 mg/kg in red wine.

The seminar included much more info and was frankly over my head but I think this summation of the highlights is good for the general public. For more information contact the seminar presenters listed above.

Thanks,

Nathan Sikes
Resources:
www.lallemandwine.us
winegrapes.wsu.edu/
Scott laboratories nicholah@scottlab.com