Fermaid® AT is a blended complex yeast nutrient developed for low to moderate YAN conditions, which supplies a well balanced mix of inorganic nitrogen (diammonium phosphate , DAP), organic nitrogen (wine-yeast derived) and the vitamin thiamine. • The nitrogen content of Fermaid ® AT is composed of inorganic (NH4+) and organic nitrogen (amino acids and peptides). • The NH4+ component is involved in biomass production of yeast cells. Reaching critical biomass is essential for successful fermentation. • Organic nitrogen is assimilated more gradually than inorganic nitrogen. Different amino acids are taken up at different rates. Once inside the cell the alpha amino acids are integrated directly into proteins, degraded into ammonium (NH4+), or used to produce fruit driven esters. • The addition of thiamine to this complex nutrient allows for an improvement in the assimilation of both nitrogen sources and reduces the risk of off flavour production. This preparation is designed to assist wine yeast in the latter half of alcoholic fermentation (AF). The DAP component will help build biomass in low to moderate YAN conditions, promoting a strong culture. Near the end of fermentation when the alcohol concentration has resulted in an inhibition of nitrogen transport across the membrane, the organic nitrogen component of Fermaid® AT (assimilated early AF) can be used by the yeast cells. This results in a healthier yeast cell at the end of fermentation and a reduction in the ‘tailing off’ effect of fermentation rate. When Fermaid® AT is used in place of a DAP-only nutrient strategy, significant improvements in the sensory profiles of the wines are also evident. Fruit driven esters and a reduction in sulphidic characters can be achieved.
KEY NOTES ON NUTRIENT DOSING FOR EFFICIENT ALCOHOLIC FERMENTATION Initial YAN is an indicator of the nutritional composition of the must, but other factors need to be taken into consideration that also dictate the quantity of nutrient that is needed to ensure complete fermentation. Factors affecting nitrogen utilization and requirements • pH: Active transport systems are affected at low pH. High pH optimum for ammonium transport. • Ethanol toxicity: Active transport process such as amino acid accumulation is inhibited in the presence of alcohol. • Temperature: the rate of accumulation of amino acids is reduced at low temperatures. • Plasma membrane composition: low sterols will reduce the efficiency of nitrogen transport. • Yeast strain: different yeast strains have different nitrogen requirements and rates of assimilation; refer to the datasheet for the yeast to be used. • Wild yeast: will provide competition for nitrogen sources. • Yeast Dose rate: The use of DAP-only can lead to a yeast biomass higher than required, hence leading to a higher nitrogen demand than initially anticipated. • Maximum Dose for New Zealand produced wine destined for EU is 40g/hL
FERMAID® AT COMPLEX YEAST NUTRIENT
Ver 2.0 / 09.2017
LALLEMAND OENOLOGY
LALLEMAND AUSTRALIA Tel: +61 (0)8 8276 1200 | Email:
[email protected] |
www.lallemandwine.com
NUTRIENTS / PROTECTORS
The information herein is true and accurate to the best of our knowledge; however, this data sheet is not to be considered as a guarantee, expressed or implied, or as a condition of sale of this product.
GUIDELINES FOR USE Re-suspend Fermaid® AT in 10x its weight in water. Ensure it is well dispersed with no lumps, then add immediately to the tank. Dose Rate of Fermaid ®AT – Refer to table below. Fermaid AT is recommended for low YAN conditions. A 20g/hL dose of Fermaid AT provides 24mg/L of actual YAN. For moderate to high YANs Lallemand recommends to use the product Fermaid O. A 20g/hL dose of Fermaid O will give 8.6mg/L of actual YAN.
Circumstances such as fruit quality, variety, winemaking practice, must parameters, yeast nutrient demand and cellar conditions are infinitely variable and impact on yeast performance.
Juice/Must YAN Yeast Rehydration Start AF 1/3rd AF >200 mg/L Go-Ferm® Protect Evolution 30g/hL Fermaid®O 20g/hL 125-200 mg/L Go-Ferm® Protect Evolution 30g/hL Fermaid®O 20g/hL Fermaid®O 20g/hL 70 - 125 mg/L Go-Ferm® Protect Evolution 30g/hL Fermaid®O 40g/hL Fermaid®AT 20g/hL <70 mg/L Go-Ferm® Protect Evolution 30g/hL Fermaid®AT 30g/hL Fermaid®AT 30g/hL
PACKAGING AND STORAGE