Gelato Display Case Temperature: Setpoints That Work
Table of contents
The number glowing on the front of your vetrina is not the temperature of your gelato. It is the temperature of some air, measured somewhere, by an instrument allowed to be two degrees wrong. Learning to read that gap is the difference between scoopable pistachio and a tray of crusted stone.
The controller reads air. Your customer eats product.
Air temperature is not product temperature, and the standard says so
This is not folklore. ISO 23953-2:2023, the international standard for refrigerated display cabinets, requires cabinets to carry a temperature display showing "the air temperature in the refrigerated display cabinets," and then attaches a note in plain language: "As a rule, measured air temperature is not identical with foodstuff temperature in refrigerated display cabinets."
The standard goes further and tells you how loose the reading is allowed to be. The measuring instrument must cover at least -25 °C to +15 °C, resolve to 1 °C or finer, and stay within a maximum error of 2 K across the whole range. Its sensor may have a t90 response time of up to 20 minutes, meaning it needs a third of an hour to show 90 % of a sudden 20 °C change.
Put those together. A display reading -14 °C could legitimately be air at -16 °C or -12 °C, reported with a twenty-minute delay, while the gelato in the middle of the pan sits somewhere else again. That is not a broken cabinet. That is the cabinet working to specification.
What the L-classes actually promise
Cabinet datasheets quote temperature classes, and this is where the standard becomes genuinely useful, because the classes are defined on product temperature, not air. Testing uses standardised M-packages placed through the cabinet, and the class describes what happened to the warmest and coldest of them.
| Class | Warmest package must be at or below | All packages must reach at or below |
|---|---|---|
| L1 | -15 °C | -18 °C |
| L2 | -12 °C | -18 °C |
| L3 | -12 °C | -15 °C |
Read that table twice. An L3 cabinet is allowed to leave its warmest pan at -12 °C. If you are holding gelato for service, that is roughly right. If you imagined the cabinet was doing storage work, it is not, and the difference shows up as ice recrystallization in whatever sits there overnight.
One important caveat: ISO 23953-2 states in its scope that it is not applicable to "ice cream freezers covered by ISO 22043," and adds that "this document is not intended to specify storage temperature for foodstuff." The classes are a comparable test result, not a food safety instruction. What you hold gelato at is your decision, recorded in your HACCP plan.
Setpoints that actually work
Italian practice serves gelato at roughly -12 to -14 °C, warmer than industrial ice cream, which is why serving temperature is a craft variable rather than a fixed rule. Working backwards from that target gives you the setpoint.
| Cabinet type | How it cools | Typical air setpoint | Why the offset |
|---|---|---|---|
| Ventilated vetrina | Forced cold air over the pans | -16 to -18 °C | Air must run colder than product to overcome glass, lights and open-front load |
| Pozzetti, dry well | Cold air or plates around each well | -15 to -17 °C | Conduction through the well wall is efficient but the lid dominates |
| Pozzetti, brine bath | Glycol or brine in contact with the canister | -14 to -16 °C | Liquid contact means product tracks the bath closely |
The pattern is consistent: the harder the heat has to travel, the wider the gap between the number you set and the number your customer tastes. In a ventilated cabinet the offset is typically 2 to 4 K. In a brine well it can be under 1 K, which is exactly why pozzetti hold product more gently than an open vetrina.
Quick reference. Set the air, then verify the product. Put a calibrated probe into the centre of the pan, not the surface, wait for it to settle, and adjust the setpoint until the product reads -12 to -14 °C at the warmest position in the cabinet. Repeat in summer.
Figure 1: three probe positions in the same cabinet, three different answers.
The ambient you never specified
Every cabinet is tested and declared for a climate class, and it only guarantees its performance inside that envelope. Climate class 3 corresponds to an ambient of 25 °C and 60 % relative humidity. A cabinet declared for class 3 and installed in a shop that hits 30 °C on an August afternoon, with the door propped open and sun on the glass, is being asked to do work it was never rated for.
This is the single most common reason a vetrina that behaved perfectly in April starts producing soft edges and weeping surfaces in July. Nothing failed. The room changed. Before you adjust the controller, check the three things that actually shifted: ambient temperature, humidity, and how often the front is open.
Why ventilated cabinets dry your gelato
Forced air is efficient at moving heat and equally efficient at moving water. Air blowing across an exposed pan surface carries moisture away continuously, and that moisture reappears as frost on the evaporator. What is left behind on the gelato is a dehydrated, matte, slightly grainy skin: the same mechanism as freezer burn, running faster because the air is moving.
Countermeasures are all cheap. Keep pans filled to a consistent level so the airflow pattern stays predictable. Use lids or covers on anything not being served. Fit and actually close the night blind, which also cuts a meaningful share of the cabinet's energy consumption. And rotate stock so nothing sits in the display through two nights.
Never load warm product into the display
A cabinet is sized to hold temperature, not to remove heat. Product that goes into the vetrina straight from the batch freezer at draw temperature, somewhere around -5 to -9 °C, does two bad things at once. It forces the compressor into a long recovery that warms every neighbouring pan, and it lets its own ice crystals grow through the slowest possible cooling curve.
Harden it properly first. A blast chiller takes the product down fast, then it rests in the walk-in until service. Only fully hardened gelato belongs in the display. Skipping that step is the most reliable way to manufacture heat shock in your own shop.
A five-minute monthly check
Pull the probe out of the drawer and do this properly once a month, in the same order every time. Read the controller and write it down. Probe the centre of the pan in the warmest position, usually the end furthest from the air discharge, and write that down too. Note the gap between the two numbers; if it has widened since last month, the coil is frosting, the airflow is blocked, or a fan has failed. Check the night blind closes fully and the drain runs. Log all of it, because the log is what turns a controller reading into a defensible record.
Related Concepts
- What Temperature Should Gelato Be Served At sets the target this whole article works backwards from.
- Pozzetti vs Display Case compares the two serving formats on cost and shelf life.
- Walk-In Freezer for a Gelateria covers the storage step that has to happen first.
- Ice Recrystallization in Gelato explains what a warm display costs you.
- Freezer Burn in Gelato is what forced air does to an uncovered pan.
- Heat Shock in Gelato is the cumulative damage of every avoidable warm-up.
