current industry practices in nutrient addition uc davis march 2011

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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

R. De Nicola, 2009

• During the first 6-24 hours of fermentation most bio-available trace minerals, free amino acids and ammonia is consumed.

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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