Transcript Slide 1

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Current Industry Practices in
Nutrient Addition
UC Davis March 2011
Lars Petersen
Technical Director
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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
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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
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Trace mineral absorption
• During the first 6-24
hours of fermentation
most bio-available
trace minerals, free
amino acids and
ammonia is
consumed.
R. De Nicola, 2009
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Cellular Distribution of Nutrients
• “Daughter” cells
will have nutrient
concentrations of
30% compared to
the “Mother” cell
G.M. Walker, 2006
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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!
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• 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
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“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