Wine fermentation monitoring in an ancient rock-cut winepress

The situation

A research team is studying ancient grape varieties, the ones that made the wines of the region thousands of years ago and then largely disappeared from cultivation. Part of that work is not analytical chemistry on the finished wine but observation of the process itself: how these varieties actually behave while they ferment.

The fermentation runs where it would have run originally, in an excavated rock-cut winepress. Grapes go onto a plastered stone treading floor that drains into a lower collection vat, the whole thing open to the air under shade netting, on a hillside with no winery building, no cellar and no process instrumentation of any kind. Following a fermentation there had meant going to the site and taking a sample.

What was installed

Each vat carries its own Omni Exodus controller. On a single RS485 Modbus bus, each controller reads a DEN-100 tuning fork density meter and DO-100 fluorescent dissolved oxygen probes. Temperature comes twice over, from the density meter’s integrated PT100 and from the dissolved oxygen probes, which is useful in a vessel this exposed. Both controllers stream to OmniCloud.

The density meter is the centre of the installation. It works by driving a metal tuning fork at its free oscillation frequency; the frequency shifts with the density of the liquid touching the tines. There is nothing to wear out, no optical window to clean and no membrane to rupture, which matters in a medium full of skins, stems and pulp. It sits in the must behind a perforated stainless guard.

Both controllers were configured differently from a normal Agrinovo field deployment. Soil and irrigation installations run a deep-sleep cycle and wake periodically to save battery, because soil moisture does not change in minutes. A fermentation does. Here the controllers stay permanently awake with the sensor power rail held on, and a full reading set arrives roughly every 1.2 minutes.

How it runs

Each meter was checked against water before it went into the vat, so the record starts from a known reference. From the moment the must was loaded, both vats have been logging density, dissolved oxygen and temperature continuously, with temperature arriving independently from the density meter’s PT100 and from the dissolved oxygen probes as a cross-check.

The vintage is still in the vat and the study is in progress. The measurements themselves belong to the research team and are not published here.

Why it matters

Nothing in this installation was built for winemaking. The density meter is the same process instrument used for brine and concentration control, the DO-100 is the same fluorescent probe that goes into fish ponds, and the controller is the same unit deployed on farms. They work together here because any sensor can connect to any controller over the same bus, so an application nobody had planned for becomes a matter of choosing instruments and configuring ports.

That is the practical case for modular hardware. A closed system covers the applications its vendor anticipated. A research team measuring a two-thousand-year-old process in a stone vat on a hillside is not one of them.