Frequently asked questions about:

• Enzymes
• Fermentation management
• Yeast
• Malolactic fermentation

If you did not find the answer to your question please ' Ask our experts'. Simply fill in the form, our team of enologists will help you solve your problem!

Both liquid and granulated enzymes should be diluted in cool water prior to addition.

The optimal time of addition depends on the objective. In any case, for an homogeneous distribution, enzyme solution can either be sprayed or dripped over the grapes as they are being crushed. To improve maceration and post fermentation processes the enzyme solution can also be added to the tank before fermentation during a pump over.

The activity of enzymes is inhibited by free SO2, therefore both products should not be added at the same time. Wait for SO2 to homogenize and combine before adding any enzyme.

Bentonite adsorbs proteins , therefore inactivates enzymes.

The best solution is to use bentonite for fining after the completion of the enzyme treatment.

In any case if you need to add enzymes to a bentonite treated wine make sure it has been completely racked off the bentonite.

The level of activity of an enzyme preparation relies on several interdependent factors: time of contact, temperature and dose. For example a decrease in temperature can be compensated by an increase in the dose.

The ideal dose has to be determined taking into account the parameters listed above as well as the grape variety and the application.

DSM liquid and granulated enzymes purchased last year can be used if they were stored in the recommended conditions.

The activity loss of liquid enzymes, stored in a cool place, is minor and can be corrected by slightly increasing the dose.

Granulated enzymes are more stable, the activity loss in an unopened pack is neglectible.

Pectinases preparations are produced from a single fermentation of A.Niger during which many enzyme activities are being produced aside from the main pectinase activity. Those side activities play a valuable role in improving white grapes processing but unfortunately some of these side activities may affect color when the preparation is applied to red grapes.

Most of a red’s color extraction is takes place in the first couple of days of fermentation, therefore Rapidase® Ex Color should be added as early as possible, at the crusher or when filling the tank, along with yeast inoculation.

Rapidase® X-Press has proved very efficient in improving pressing of Muscat varieties as well as increasing juice yields, in particular free run.

In the grape berry, flavorless glycosides are in much greater quantities than the unglycosylated monoterpenes responsible for fruity and floral flavors. The glycosidase activities in AR 2000 hydrolyze these glycosides to yield free flavorsome aglycones.

As glycosidases are slightly inhibited by sugar we recommend to add a higher dose when AR 2000 is used on juice in stead of wine.

There is a great product in the DSM range that allows to breakdown betaglucans in botrytised grapes and when used in barrel aging accelerates yeast lysis for increased mouthfeel.

Unfortunately only enzymes produced by Aspergillus niger are ATF approved, the Betaglucanases produced by Tricoderma used in our product are not allowed in the United States.

Lysozyme is an enzyme extracted from egg white, it is known to inhibit Gram positive bacteria including lactic bacteria. This property is commonly utilized by DSM in the Dairy industry, in winemaking Lysozyme can be used to monitor the occurrence of malolactic fermentation or to inhibit unwanted bacteria. The addition of Lysozyme to wines will increase microbiological stability and allow a reduction of SO2 doses.

DSM has a lysozyme preparation called Delvozyme® unfortunately this product is not currently distributed in the United States.

The level of activity given by different suppliers do not compare as each enzyme manufacturer has their own way of measuring the activity of their preparations. The methods differ in the pectin solution used as a reference and in particular their degree of methylation. A comparison of products should always involve a production trial in which our technical service would be happy to assist you.

GRAS stands for Generally Recognized as Safe. This statement applies to micro organism used in the food industry, all DSM enzymes available in the united States are produced by GRAS strain of Aspergillus Niger.

DAP only provides the yeast with ammonium salt whereas Maxaferm® F is a complete formulation. Maxaferm® F not only provides nitrogen in the form of ammonium phosphate but as it contains inactivated yeast it also provides amino acids as well as other compounds that help prevent stuck and sluggish fermentation.

MAXAFERM® F is a fermentation bio regulator based on inactivated yeast, thiamine and Di-ammonium phosphate:

• Thiamine and ammonium salt support yeast growth and metabolism.

• Inactivated yeast contain amino acids as well as sterols and fatty acids respectively providing assimilable nitrogen and strengthening the yeast against alcohol. Inactivated yeast also play a protective role by fixing inhibitors.

DSM and INRA conducted trials on a must with a history of stuck fermentation to find out the most efficient time of addition of several nutrients: Competitors yeast foods, DAP, Oxygen and Maxaferm®. Those trials have shown that an addition of 4 lbs./1000 Gallons of Maxaferm® at mid-fermentation (14 to 16 Brix.) along with a pumping over with air allowed to complete fermentation and increase yeast viability at the end of fermentation.

The proper rehydration of yeast is crucial to ensure a healthy fermentation. As the inner content of yeast cells is very concentrated, it is necessary to use a 5% sugar solution (1,5 lb. sugar in 4 Gallons of water) to avoid an osmotic shock that would cause yeast cells to burst resulting in a starter with very little viable yeast cell.

The respect of other parameters such as temperature and timing also play an important role in obtaining a healthy starter, so when preparing your starter make sure to follow carefully the “How to use” directions at the back of every DSM yeast product sheet.

It is definitely better to use direct inoculation, as it will help prevent problem fermentation. Due to the extended number of yeast generations when using mother tanks, the sterol content in the cells decrease considerably resulting in dramatically enhanced yeast sensitivity to ethanol.

There is seldom a single cause of stuck fermentation:

If the arrest is due to overheating or overcooling, bringing the temperature back around 68°F should be enough for the fermentation to restart.

If the arrest is due to a decrease in yeast viability and their incapacity to complete fermentation,

• Rack the wine to remove struggling yeast, unwanted bacteria and any inhibitor. Moderately sulfite the wine (SO2 30 to 40 PPM) to prevent the risk of bacterial infection and favor the newly inoculated yeast development.

• Prepare a starter with Fermichamp® using 4lbs/1000 Gallons of stuck wine, carefully following the instructions given at the back of the product sheet.

The specific ability of Fermichamp® to metabolize fructose in high alcohol conditions makes it the ideal yeast for problem fermentation.

It is very difficult to stop spontaneous malolactic fermentation.

If you are willing to conduct partial malolactic fermentation on your wine it is easier to do so by blending wines that completed malolactic fermentation with wines that did not go through ML.

In order to prevent ML you can use several methods separately or in combination:

• Low temperature

• Sulphur dioxide

• Lysozime.

Besides a loss of acidity resulting in an increase of the pH, by-products of malolactic fermentantion have a major impact on wine: loss of fruity flavour, appearance of new aromatic compounds , increased mouthfeel.

Generally, a wine that went through malolactic fermentation is well balanced and has a complex aromatic profile.

• Alcohool below 14% vol

• Temperature superior to 15°C (59°F)

• pH superuor to 3,0

• Total SO2 under 60 mg/l

• Free S02 under 10 mg/l

• Minimum number of cells : 10E6 UFC/ml

Nutrients such as carbohydrates, vitamins or amino acids are essential for the lactic bacteria development.

As lactic bacteria cannot metabolize inorganic nitrogen and do not have proteolytic activity, the whole amino acids pool is necessary.

Several growth factors and vitamins such as thiamin and biotin are also required.

The use of an adapted ML nutrient, based on inactivated yeast, will supply these substances in sufficient quantities to conduct a healthy ML fermentation.

The problem when malo lactic fermentation occurs before the end of alcoholic fermentation comes mainly from the lactic bacteria hetero-fermentary metabolism of glucose and fructose. This metabolic path leads to the formation of lactic and acetic acids, resulting in an increase in the “buttery flavor”, as well as volatile acidity.

It is advised to conduct malolactic fermentation right after alcoholic fermentation when conditions are optimum.

• Temperature

• Nutrients provided by dead yeast

• It also has been proved that small quantities of CO2 help lactic bacteria develop.

In order to follow the development of malolactic fermentation you should control the following parameters:

• pH: increases during malolactic fermentation;

• Total acidity : decreases;

• Malic acid/Lactic acid decrease. During ML malic acid is consumed and lactic acid is synthesized, therefore their ratio decreases.

• Increase in volatile acidity by 0,1-0,15 g/l. A higher increase could be the symptom of spoilage.