Novozymes’ pectinases for wine-making – exceptional purity to ensure quality

Enzymes have been used, although unknowingly, for thousands of years in the production of wine. Today, commercially produced enzymes benefit a number of aspects of the wine industry, including maturation, extraction, clarification, and filtration. Novozymes’ range of pure pectinases for wine making effectively preserve and protect the freshness and fruitiness of both red and white wines. Suitable for organic production, these solutions compliment the naturally occurring enzymes in wine.

 

What is truly unique about Novozymes’ pectinases is their exceptional purity. An extra purification step in production creates ‘FCE enzymes’ – enzymes that are almost free from cinnamyl esterase. The process, based on a pH treatment, removes enzymatic side activities such as cinnamyl esterase, which is detrimental to wine quality, and additional minor side activities. The pectinase batches are controlled throughout the production steps to monitor this activity. All pectinases that are produced by Aspergillus contain a certain amount of cinnamyl esterase activity in addition to their main pectolytic activities, but thanks to this specific purification step, cinnamyl esterase activity can be reduced to as low as 0.5 CINU/1000 PGNU - or even lower (CINU: Cinnamylesterase Unit – PGNU: Polygalacturonase Unit). This well-mastered process has been the standard purification process at Novozymes since 1993, and is a guarantee of quality. 

 

The cinnamyl esterase activity present in pectinase preparations stemming from Aspergillus niger was first recognized by Burkhardt in 1976 as being responsible for the loss of freshness and fruitiness in fine German white wines. At that time, the substances responsible for the sensory defaults were not identified. However, this discovery saw the use of FCE pectinases, known as “depsidase free” pectinases, becoming a preferred solution in the German market. Although the cinnamyl esterase activity was purified from Aspergillus niger in the eighties by Schöbel and Pollman, the route that forms phenolic off-flavors in white wines was only clarified by Chatonnet, Barbe and Dubourdieu in the nineties at the Bordeaux Wine University.  Cinnamyl esterase activity is the first step in the formation of precursors in the form of free acid phenols used by yeast to release volatile vinyl phenol. This unwanted activity is even more damaging to the fruitiness of wines produced in hot regions, as the level of tartaric esters of hydroxycinnamic acids is much higher in warmer climates, as demonstrated by Van Wyk in South-Africa. As all white wine varieties are sensitive to vinyl phenol off-flavors (medicinal in taste), Novozymes introduced FCE pectinase preparations for wine-making to prevent the formation of these compounds. 

 

The formation of volatile phenol also occurs in red wines, and the presence of Brettanomyces transforms it into ethyl phenols, which are responsible for off-flavors. The removal of cinnamyl esterase activity also reduces “anthocyanase” activity, which limits color loss. Research on the effects of esterase was demonstrated in red varieties in Oregon by Wightman and Wrolstad, through showing the cleavage of tartaric acid from caffeol tartrate to form caffeic acid. Recent studies by Ducasse, Fulcrand and Cheynier at INRA Montpellier, demonstrated the combination of vinyl phenol with anthocyanins to form vinyl phenol-anthocyanins adducts. Cinnamyl esterase present in pectinases is clearly involved in the formation of these adducts by releasing free hydroxycinnamic acids, as is found in white wine making. The research work shows that the use of FCE pectinases prevents the alteration of red wine composition. In conjunction with partners and distributors, Novozymes has offered FCE pectinases for red winemaking since 2000 with great success.

 

The benefits that enzymes offer the wine industry are diverse and substantial.  Enzymes optimize maceration (mash treatment) during wine production to release colors and aroma compounds as well as facilitating wine maturation, and filtration enzymes make red wine filtration a problem-free, smooth and reliable process. In the case of clarification or must treatment during wine making, enzymes speed up settling and ensure the efficient sediment compaction of red and white wine as well as rosé musts.  Enzymes accelerate maturation in wine, removing the risk of off-flavors and enhancing the aroma.   The prevention of off-flavors is essential in both white and red wines to serve a market seeking fresher and fruitier wines, and Novozymes secures this desired quality with exceptionally pure FCE enzymes.