4/8/2014 Tonight’s Lecture Review exam 2 and final project Fining Agents and Particles that form haze in wine Winery Sanitation How fining agents work Bentonite Wine 3 Other fining agents Introduction to Enology Cleaning and sanitation methods Cleaning compounds 4/8/2014 1 2 New file on links page Remember Next week is the second exam There is a new link It will cover wine additives & sulfur dioxide to a good article up through tonight’s lecture. from Washington You will need a Scantron form 882-E and a State University on calculator. the use of fining agents in wine. 3 4 Final Presentation Final Presentation A 5 to 10 minute oral presentation along with What to discuss: an written outline on any wine that is of Grape source, vineyard location, soil & interest to you. climate, vineyard cultural practices, It cannot be a wine that you have made or one varieties, harvest criteria. from where you work. Grape crush and fermentation, what the If possible bring in a bottle to taste with the vintage conditions were. class, food to accompany your wine is also Processing, aging, blending and bottling of welcome. the wine. Buy the wine before you start work! 5 6 Fining & Sanitation 1 4/8/2014 What to discuss: Two most important things to address: The wine itself, the chemical statistics, Tell me what the winery and winemaker flavors, textures and aromas of the finished did to make it taste the way it does. product. The most important aspect is to select a What you like/don’t like about the wine, wine that you think is significant. why you chose it, what you would do Email Chris and I which wine you have differently if you were the winemaker. selected before the final lab. 7 8 Guidelines for outline Fining Agents All you own words, no cutting and pasting text from internet. Fining agents are materials added to wine that Bring a copy to hand in and one for yourself to react with chemical constituents in the wine use during your presentation. It should be to affect its composition. about one single-spaced page. Fining agents are not soluble (will not Be sure to start the outline with your name and dissolve) so they settle or get filtered out so the name of the wine that your are presenting. no residual fining agent is left behind. If you want to use Power Point slide or food to share talk/email me or Chris first. 9 10 Effects of Fining Agents Commonly used fining agents Clarity, fining agents can facilitate the removal There are a great number of fining agents that of suspended solids from a wine. are available to winemakers to a adjust a Color, some fining agents will reduce color. wine’s flavor and chemistry. Stability, fining agents are added to wine to Tonight we will discuss the more common insure that a brilliant wine remains so. fining agents. Sensory adjustment, Fining agents can be Before discussing individual types we will go added to remove or alter flavor components over how they function. that are in the wine to affect flavor. 11 12 Fining & Sanitation 2 4/8/2014 Particulate Matter in Wine Size Distribution of Particulate Matter in Wine Particles in wine are insoluble or semi-soluble solids that are suspended; these make a wine dull or hazy. # of Particles Particles in wine include: yeast & bacteria, condensed tannins, proteins, bitartrate crystals, and polysaccharides. Particle Size μm (microns or 1/1000 of a mm) There are two properties that are important Notice: the large range of particle size and to settling, size distribution and that the distribution is clustered around the electrostatic charge. smaller sizes. 13 14 Particulate Matter in Wine Particulate Matter in Wine The rate of settling is influenced by: The rate of settling is influenced by: Size of the particle, smaller particles settle Height of the tank, taller tanks settle out out more slowly. more slowly. Protective colloids (polysaccharides, gums, When getting a lab sample the wine at the glucans and dextrins). These envelop particles top of the tank is usually much cleaner than and prevent them from binding together; the wine from the base. more pronounced with moldy grapes. 15 16 Electrostatic charge Most particles in wine have a negative charge, When getting except for proteins which are positively samples the charged. cleanest wine Proteins positive + is near the Most other particles are negative - top. Since like charges repel they must be neutralized before they can bind together, once particles are bound together they are heavier and settle out faster. 17 18 Fining & Sanitation 3 4/8/2014 Electrostatic charge Using fining agents Proteinaceous (protein based) fining agents Most fining agents do have a positive charge and they bind with not dissolve in wine but remain as negative particles in the wine and form particles in particles with a heaver weight and a neutral suspension. charge that settle or filter out more easily. Solid objects in wine are surrounded by a boundary layer of non-moving liquid. 19 20 Using fining agents Bentonite & Heat Stability The more turbulence during mixing the better Proteins are made out of chains of Amino the fining agents will react with the particles Acids. in the wine. A proteins shape is determined by its This is why it is so important to mix the wine sequence of amino acids. very well when adding fining agents. A proteins function is determined by its Several smaller additions of a fining agent shape. work better than one large one (unlike SO2). 21 22 Protein Synthesis Amino acid structure Each amino acid has the following structure, The sequence of amino acids in a protein is each with a different “R” group attached. determined by the order of the base pairs in There are 20 different amino acids. DNA. Although it is not directly relevant to winemaking we will briefly review how proteins are made. There are over 100,000 different proteins in the human body. This slide will not 23 be on test 24 Fining & Sanitation 4 4/8/2014 DNA Base Pairs The 20 Amino Acids Amino The 20 This slide will not be on test 25 This slide will not be on test 26 RNA polymerase unwinds the DNA and attaches the complementary nucleotides to form messenger RNA. This slide will not be on test This slide will not be on27 test 28 Protein Stability So, why should you care? Proteins in wine can become unstable over time and denature (lose their structure) becoming insoluble. This leads to a cloudy precipitate in the wine. The denaturing is a very slow reaction and can make a wine that is brilliant to become cloudy after it has been bottled for several months. This slide will not be on test 30 Fining & Sanitation 5 4/8/2014 Protein Stability Protein Stability This is the same reaction that takes place when an egg is cooked. Egg whites are made of albumen (egg protein) and when the are denatured by heat they become solid and turn white. 31 32 Bentonite Fining Bentonite Bentonite is used in white, blush, and rosé Bentonite is a type of clay that is negatively wines to remove excess proteins and make charged and binds with positively charged the wines heat stable. proteins. Red wines do not require because they have The charges are neutralized and the much more tannins than white wine. Since protein/bentonite particles become insoluble tannin molecules are negatively charged, and settle out. during ageing they react with protein in a It is the most commonly used fining agent similar manner as bentonite. 33 34 Bentonite Bentonite Structure There are two types: Bentonite particles form a Sodium Bentonite is more easily planer structure with dissolvable, less of a respiratory irritant and positive charges on the more effective in fining wine. More edge and negative charges common in US. on the flat surface. Calcium bentonite produces less lees, but is less effective so you use more. More common in Europe. 35 36 Fining & Sanitation 6 4/8/2014 Bentonite Fining Bentonite Fining The amount of bentonite required to make a Like all fining agents it is best to do fining wine protein stabile is dependent on the variety, trials first to see how much is needed. vineyard and vintage. Large additions of bentonite can strip a wines Many Chardonnays don’t need any bentonite, I flavor, partially due to dilution. have seen Sauvignon Blancs that needed more than 14# / 1000 Gal. 37 38 Heat Stability Testing Heat Stability Testing Heat accelerates the formation of protein This is not an absolute test, so many wineries hazes; to perform the lab test, add different have variations on the temperature and time. concentrations of bentonite to wine samples. This is not done to protect the wine against Let settle, filter, and put in an oven at 125°F heat, but to use the high temperature to (50°C) for 48 hours and then look for haze simulate the effects of long term aging. under a high intensity lamp. You add the The terms protein stability and heat stability smallest amount that is clean. are used interchangeably. 39 40 Heat Stability Testing Heat Stability Testing After heating the samples are checked for clarity Fined samples before filtering Stable @ 3#/1000 gal. Unstable @ 2#/1000 gal. Oven for filtered samples 41 42 Fining & Sanitation 7 4/8/2014 Adding Bentonite When to Add Bentonite? Mix Bentonite at the rate of 1 gram/25 ml Bentonite can be added as juice or as wine.