Milk pasteurizer: VDP vat or tubular — which to choose

In short. Milk is pasteurized in production in two ways: in batches in a VDP batch pasteurizer (long-time pasteurization vat) or continuously in a tubular pasteurizer. A VDP of 75 to 1,000 L heats milk to 95 °C, cools it with ice water and lets you ferment kefir, yoghurt and ryazhenka and make tvorog in the same vessel — the choice for farms and small plants. A tubular pasteurizer with a capacity of 500 to 20,000 L/h and more pasteurizes milk continuously at 80–90 °C — equipment for dairy plants and continuous lines.

Two ways to pasteurize milk

Pasteurization kills the microbes present in raw milk while preserving the properties of the raw material. In production this is done either in batches — the whole batch is heated and held in a jacketed vessel — or continuously — milk flows through a heat exchanger without interruption and comes out pasteurized.

The batch method is the VDP batch pasteurizer; the continuous method is the tubular pasteurizer. The Milberg plant manufactures both in-house in Yekaterinburg.

How a VDP batch pasteurizer works

A VDP is an insulated AISI 304/321 stainless steel vessel with a water jacket and an agitator. The jacket is heated by electric heating elements (standard version, 380 V), or by steam or gas on request. Milk is heated to 95 °C, with the agitator mixing it throughout the process. After pasteurization, ice water (+2…+4 °C) is fed into the jacket, and the product is quickly cooled to the inoculation or storage temperature.

A special feature of the Milberg VDP is that product and heating-medium temperatures are set separately on the control panel and maintained automatically. Low-viscosity milk is therefore pasteurized quickly, while viscous curd and cheese coagulums are heated evenly, without overheating.

In a single vat you can not only pasteurize milk but also ferment kefir, yoghurt and ryazhenka and make tvorog.

How a tubular pasteurizer works

A tubular pasteurizer consists of two cylinders — steam-heated stainless steel multi-tube heat exchangers. Milk flows through the tubes: in the lower cylinder it is preheated to 50–60 °C, and in the upper one it is pasteurized at 80–90 °C. The temperature difference between the product and the heating medium is small, so the milk heats evenly.

The pasteurizer runs continuously, with a capacity of 500 to 20,000 L/h and more; we make standard models and units to customer specifications. Besides milk, it is used to pasteurize juices, beer and kvass.

VDP vs tubular pasteurizer: comparison

When to choose a VDP

A VDP is the right choice if you process milk in batches of up to 1,000 L at a time and make cultured dairy products: pasteurization, cooling and fermentation take place in one vessel, so you do not need separate equipment for each operation.

The vat volume is calculated from the amount of milk per pasteurization run. Standard volumes are 75, 100, 200, 350, 500, 630 and 1,000 L. Popular sizes are often in stock; on request we make versions with a cleaning head, or for steam or gas heating.

When to choose a tubular pasteurizer

A tubular pasteurizer is needed when milk moves in a continuous flow — at a dairy plant, on a reception line or a filling line. We size the capacity to the line: from 500 L/h to 20,000 L/h and more.

Where this equipment is already in operation

Milberg VDP batch pasteurizers operate on farms, in dairy workshops, cheese dairies and private businesses — from the VDP-75 for small batches to the VDP-1000 for a dairy workshop — including on Sakhalin, in Chukotka and in Kazakhstan. Tubular pasteurizers have been supplied, for example, for milk reception (TT-4000, 4,000 L/h) and together with a milk pump (PT-2000, 2,000 L/h). All projects are in the ["Case studies"](/projects/ section.

Not sure which one suits your production? Tell us how much milk you process per shift and what you plan to make, and our dairy process engineer will select a pasteurizer and send you a quotation within one working day. All equipment for this stage is in the "Milk processing equipment" section.