Una necessità molto sentita in cantina

La misura dell’APA negli attivanti di fermentazione

Una metodologia di misura che si basa su una lettura fotometrica

Data la grande diversità chimica dei composti azotati dell’uva che possono essere assimilati dai lieviti – tra cui, oltre all’ammonio e aminoacidi, anche ammidi, purine, pirimidine, vitamine e peptidi – la misura dell’APA rappresenta una sfida.
Molti sono i metodi analitici a disposizione, spesso tuttavia dispendiosi in termini di costi e tempi, oltre che di difficile applicazione.
In cantina, però, c’è la necessità di monitorare il contenuto in APA del mosto per verificare le eventuali carenze e di ripristinare il contenuto in azoto assimilabile necessario per un corretto svolgimento della fermentazione alcolica, mantenendo bassi i costi ed i tempi di esecuzione.
Lo scopo di questo lavoro è stato quello di misurare l’apporto in APA che diversi attivanti del commercio possono fornire se aggiunti al mosto in fermentazione, utilizzando una metodologia che si basa su una lettura fotometrica, facile e sicura, che può essere tranquillamente svolta in cantina.

L’ARTICOLO COMPLETO A FIRMA ALESSANDRA RINALDI E LUIGI MOIO E’ PUBBLICATO A PAGINA 24 DEL FASCICOLO 5/2017 DI VVQ. PER ACCEDERE ALLA RIVISTA ONLINE E’ NECESSARIO ESSERE ABBONATI.

VAI ALLA PAGINA DEGLI ABBONAMENTI

PER APPROFONDIRE

(Approfondimenti a cura degli Autori)

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