Fabio Mencarelli,* Giuseppe Floridia, and Andrea Uliva
*University of Pisa, Via del Borghetto 80, 56126, Italy (fabio.mencarelli@unipi.it)

Resonance waves are very diffuse. A resonance wave promotes movement of liquid (or gas) with a continuous, constant wavelength until creating a paroxysmal liquid movement that provokes wave fracture or, in the presence of solid material, its disintegration. The AIRMIXING M.I technique for grape maceration is based on this physical principle, creating resonance waves in the must within the tank. A well-identified sequence of air-jet pulsing with studied pressure creates this soft, sustainable, maceration technique. Soft because there is no contact between metallic components and must (punch-down), thus no friction effect; no invasive movement (pumping-over); and sustainable because racking is simplified and neither push down nor pumping over are required. This saves energy and labor: very little energy is required to activate the air nozzles. In this paper we report collected data from different applications of AIRMIXING M.I. around the world. If pumping-over during fermentation/maceration requires ~1700 min of cooling plant running, AIRMIXING M.I. requires only ~420 min, saving 75% of the electricity, and facilitates a more uniform must temperature in the vessel. A comparison in racking time shows that AIRMIXING M.I. needs 2 hrs for a 3000 hL vessel versus 6 hrs with pumping over. Beyond the sustainability aspect, the quality of extraction is excellent because of the uniform temperature in the vessel and can be modulated by adjusting the jet air nozzle sequence and opening time.

Funding Support: Parsec srl