HTST means high temperature, short time. It is a continuous pasteurization method that heats a liquid to a regulated temperature, holds it for a short set time, then cools it quickly.

What is the regeneration section of a pasteurizer?

It is the part of the plate heat exchanger where hot pasteurized product warms the incoming cold product. It recovers heat, so the heating and cooling sections have less work to do.

Why does pasteurizer energy use rise over time?

Fouling on plates, gasket wear and poor flow control reduce heat recovery. The heating and chilling sections then work harder to hit the same temperatures.

Does Aqueduct replace pasteurizer controls or food safety records?

No. Pasteurizer controls and food safety records stay in the plant's validated systems. Aqueduct reads utility data around the pasteurizer so energy and water use can be measured and improved.

Glossary

Dairy and food processing

What is Pasteurization (HTST)?

Definition

HTST pasteurization (high temperature, short time) is a continuous process that heats milk or other liquids to a regulated temperature, holds it for a set time, then cools it quickly. A plate heat exchanger with a regeneration section recovers heat, which makes the pasteurizer one of a dairy's main steam, hot water and chilling loads.

What it is

HTST pasteurization kills pathogens in milk, cream, juice and similar products by heating them to a regulated temperature and holding them there for a minimum time in a holding tube. The legal time and temperature combinations are set by food safety rules, so plants should check the current regulation that applies to them.

Most HTST systems use a plate heat exchanger with three sections: regeneration, where incoming cold product is warmed by outgoing hot product; heating, where hot water or steam brings it to temperature; and cooling, where chilled water or glycol brings it back down. A flow diversion valve returns product that did not reach temperature.

Because heat is recovered in regeneration, the pasteurizer's energy use depends on how well the plates are maintained. Fouling, gasket leaks and poor flow control raise both heating and chilling demand.

Who it applies to / where it is used

HTST is used in fluid milk, flavored milk, cream, ice cream mix, juices and liquid egg processing. Dairy plants usually run several pasteurizers, and each one draws on the boiler, the hot water set and the refrigeration plant at the same time.

How it is measured / what evidence it needs

Food safety records cover time, temperature and diversion. Utility performance needs a second layer: the heat and cooling each pasteurizer uses per liter processed.

Product flow through each pasteurizer
Heating medium and chilled water temperatures in and out
Steam or hot water energy and chilled water load per liter
Regeneration efficiency trend as an early sign of fouling
Run hours, CIP cycles and diversion events

How Aqueduct helps

Aqueduct places each pasteurizer on the plant's digital twin so heat, cooling and product flow are read together.

aQ EnergySmart calculates heating and chilling energy per liter for each pasteurizer
aQ PredictIQ flags falling regeneration performance that points to fouling or plate issues
aQ WaterGuard links pasteurizer CIP and cooling water to the plant water balance
Food safety records stay in the plant's validated systems; Aqueduct adds the utility view