Enzymes

Question 1

Enzyme definition

Answer 1

A (mostly) protein that helps speed up a reaction.

They can: aid in extraction, enhance aromas, clarify, block MLF, increase juice yield. Plus there are spoilage enzymes.

Inhibited by: pH, temp, SO2

Fun Fact: Commercial enzymes originally used by fruit juice industry in the 1950s, adopted by wine industry in the 1970s

Question 2

Common enzymes

Answer 2

Laccase: An oxydizing enzyme produced by botrytis.
- During the cold wet 2011 growing season in Napa, many producers including Stephane Vivier at Hyde de Villaine, added powdered tannin and SO2 to combat this enzyme.

Lysozyme: derived from egg whites, anti-bacterial (does not harm yeast). Used to delay MLF and also by Champagne producers in the liqueur de tirage.
- In 2013, Houndstooth Sonoma Coast Pinot Noir started to undergo MLF during primary ferment resulting in creeping VA levels; they added lysozyme to stop this action and then later inoculated for MLF once primary was completed.

Glycosidase enzymes: formed by yeast, used to unbind aroma compounds from sugars, esp terpenes.
- Some yeast naturally produce more of this. Can select for a strain of such yeast or just add beta-glucosidase

Pectolytic enzymes: widely employed in winemaking. Break down pectins (cell walls) which liberates juice thereby increasing yields, increase quantity of aromatic precursors, used often in white wine settling, makes filtration faster, easier, and cheaper, can shorten maceration window in reds.

 - Lauren Barretti at Enartis reports that yields can increase by as much as 7% for whites, 15% for reds.
 - Dan Petroski at Massican adds Lafazym-CL to specifically remove pectins from Tocai Friulano because "if you don't carefully settle Tocai and ferment clean juice the pectins create sulfide phenols and you have a gross fart-bomb on your hands."
 - Dan Petroski also uses a macerating enzyme (pre-ferm) on his red wines at Larkmead to release anthocyanic, it also contains a pectinase that he hopes will settle out unwanted microbial activity such as Pediococcus. This enzyme is Lallzyme EX-V.
 - At Chateau Ste Michelle, David Rosenthal uses the "kitchen sink" enzyme (Scottzyme KS) to completely clarify and settle his Riesling musts prior to fermentation.

Proteases: breakdown proteins. Can improve clarification.