Current Industry Practices in Nutrient Addition UC Davis March 2011

1. Current Industry Practices in Nutrient AdditionUC Davis March 2011 Lars Petersen Technical Director

2. Observations! • Additions are done to: rehydration water, juice and first half of fermentations • Different preferences in product types. • “A La Carte” • Mainly DAP • Wholesome complex products

3. Timing of nutrient addition • Adding nutrients during the first 30-50% of fermentation is established industry practice • Important to stage both DAP and complex nutrients

4. During the first 6-24 hours of fermentation most bio-available trace minerals, free amino acids and ammonia is consumed. Trace mineral absorption R. De Nicola, 2009

5. “Daughter” cells will have nutrient concentrations of 30% compared to the “Mother” cell Cellular Distribution of Nutrients G.M. Walker, 2006

6. Timing of nutrient addition • Adding nutrients during the first 30-50% of fermentation is established industry practice • Important to stage both DAP and complex nutrients • Do not use starvation as means to control fermentation speed!

7. Adding according to YAN levels in must • Targets may vary (250-350ppm) • Historical information are important • If adding more then ~35ppm do multiple addition • Add some organic nitrogen • Target 20-30ppm • Use pure DAP when organic N target is reached

8. “The Nutrient Dessert” • Significant amount of trace elements and vitamins are naturally present juice • Free amino acids, vitamins and most trace elements are fixated in biomass • Nitrogen is incorporated in protein • Natural autolysis takes weeks or months • Spoilage during aging is often done by small populations