Industry

Food & Beverage Instrumentation & Hygienic Measurement

Sanitary flow, level, temperature and analysis instruments for filling, CIP and quality control.

What this sector has to measure

Food and beverage production shares the hygienic requirement with pharmaceutical work but not the reason for it. Here an instrument has to be cleanable because the product spoils, because residue contaminates the next batch, and because the cleaning regime has to be shown to work - not primarily because a regulator expects a qualification file.

The practical consequence is that the cleaning regime drives the specification. A line cleaned in place, one stripped and washed by hand and one running a dry product each want different connections, different surface requirements and different temperature tolerance, so the same measurement on the same product is specified three different ways depending on how the line is cleaned.

The other recurring theme is that food products change state. They are viscous, they carry particulates, they foam, they crystallise on cooling and they are frequently shear-sensitive, so a technology that works perfectly on a clear liquid can be unusable on a fruit preparation. That is a difference in the medium at the point of measurement rather than a fault in the instrument, and it is why product behaviour belongs in the enquiry alongside the measurement.

Where the instruments sit

Intake and preparation

Receiving, weighing, washing, milling and mixing. Measurements are frequently about quantity and level rather than close control, and the equipment has to tolerate dust, variation in the raw material and regular washdown.

Processing and thermal treatment

Pasteurisers, sterilisers, cookers, coolers and heat exchangers. Temperature and flow dominate, and the temperature profile is usually a control point, so the measurement feeds a record as well as a controller.

Filling, packaging and cleaning

Filling lines, dosing and the clean-in-place circuit itself. Dosing accuracy, repeatability and hygienic design matter together, and the cleaning circuit carries its own flow, temperature and conductivity measurements.

Utilities and effluent

Steam, chilled water, compressed air and the effluent plant. Standard industrial instruments are often acceptable here, and this is normally where a food plant can reduce cost without touching product quality.

Instrumentation used in this sector

Measurement	What is measured in this sector	Instruments commonly specified
Flow	Product lines, dosing, cleaning solution, steam for thermal treatment and water	Electromagnetic meters with hygienic liners for conductive liquids, Coriolis meters where dosing or a mass figure is required, positive-displacement meters for viscous products, and vortex or differential-pressure installations for steam
Pressure	Pasteuriser and filler pressure, differential across filters and membranes, and pressure in the cleaning circuit	Hygienic transmitters with flush diaphragms, and differential transmitters where both sides of the diaphragm have to be cleanable
Temperature	Thermal treatment, cooling, cleaning temperature and cold store monitoring	RTDs in hygienic thermowells where stability and a record are wanted, and surface or non-contact measurement where a probe cannot enter the product
Level	Silos, process and buffer tanks, mixers and separator interfaces	Radar and guided-wave transmitters selected for the antenna and for the product, hydrostatic transmitters for simple vessels, and switches sized for a product that may bridge or coat
Analysis	pH, conductivity, turbidity and dissolved oxygen in product, water and cleaning returns	In-line analysers with hygienic connections, and conductivity measurement in the cleaning return line to confirm that the cycle has actually been completed
Inspection	Metal detection, checkweighing, foreign body inspection and package integrity	Inspection equipment mounted in the line where it can reject without stopping production, with the reject mechanism and the record designed together rather than separately

What is acceptable depends on the hygiene class of the area and on the cleaning regime the line follows. Both should be stated in the enquiry.

How to specify for a food and beverage plant

The cleaning regime first: cleaned in place, cleaned out of place, or a dry product. It decides the connection, the surface and the temperature the instrument has to survive.
The hygiene class of the area, which is a separate question from the cleaning regime and applies to the environment around the instrument as well as to the parts that touch product.
Contact materials and the declaration covering them, since any wetted part in a product-contact position is expected to arrive with documentation.
Product behaviour at the point of measurement: viscosity, particulates, aeration, shear sensitivity, and whether the product changes state as it cools or as it is pumped.
Control points, where a measurement forms part of the food safety record rather than only of a control loop, and therefore carries a calibration and documentation requirement of its own.
Drainability, orientation and the elimination of dead legs, because a residue that survives cleaning is a product quality problem rather than a maintenance one.
Temperature during cleaning, which is normally higher than the process temperature and is the value the instrument is actually chosen against.
Whether the instrument has to survive the cleaning chemical as well as the product, since a caustic or acidic cycle is frequently the more aggressive of the two duties.

Standards and approvals that may apply

Hygienic equipment design principles, which govern surface finish, crevice avoidance and drainability rather than any instrument specification.
Food safety management expectations, which place the documentation and calibration obligation on the plant and therefore reach back to the supplier of the instrument.
Material contact declarations for parts in a product-contact position, commonly required by customers auditing the plant.
Inspection and weighing obligations where equipment forms part of a control point in the food safety plan.
We describe what an installation may have to meet. We do not claim that any approval is held for a product unless the corresponding document has been supplied, and the product pages follow the same rule.

Applications in this sector

Frequently asked

Food & Beverage sourcing questions

The questions that come up in this sector before an order. If yours is not here, send it with the duty and we will answer it alongside the quotation.

What makes an instrument hygienic rather than merely stainless?

The design of the wetted surfaces, not the alloy. A hygienic instrument has connections that can be cleaned in place, a surface finish that can be verified, no crevices, no threads and no dead legs in the product path, and it drains by gravity. A stainless threaded instrument with a machined body can be perfectly corrosion resistant and still be unacceptable where it contacts product.

Should product dosing use an electromagnetic or a Coriolis meter?

It depends on what the dose is measured in. Electromagnetic meters suit conductive liquids and are the usual choice where volume is acceptable, provided the product conducts and the liner suits it. Coriolis meters measure mass directly and are chosen where the dose is defined by weight or where the value of the product justifies the cost. Viscous products and those with particulates often rule out one of the two before the range is discussed.

How is cleaning verified?

Conductivity in the returning cleaning solution is the usual continuous indication, because it shows whether the intended concentration is circulating and whether the cycle has completed. Temperature and flow in the circuit are measured alongside it, since a cleaning cycle that is too cool or too slow does not do the job whatever the concentration. The verification logic belongs in the cleaning control system rather than in the instrument.

What temperature should a hygienic instrument be rated for?

The cleaning temperature rather than the process temperature, because that is normally the higher of the two and it is where the instrument fails if it is under-specified. Where sterilisation in place is carried out, that condition is higher again. State both the process and the cleaning temperature, and the cleaning one will govern the selection.

Can standard industrial instruments be used in a food plant?

In the non-product areas, yes, and it is often the sensible choice. Utilities, effluent, compressed air and the general plant services do not contact product, so hygienic design buys nothing there. The line is drawn by contact with product rather than by the fact that the building produces food, and applying hygienic requirements across the whole site adds cost without adding safety.

What should a food and beverage enquiry include?

The measurement and where it sits, the hygiene class of the area, the cleaning regime, the product behaviour at the point of measurement, the connection standard the plant already uses, the process and cleaning temperatures, whether the measurement forms part of a control point, and which contact-material documents have to accompany the order. Those answers decide the instrument before the range does.

Published products

Instruments available for this sector

PID Controllers

Panel-Mount PID Temperature Controller

Panel-mount PID temperature controllers in four panel sizes, taking thermocouple, RTD, 4-20 mA or 0-10 V inputs and driving relay, SSR, linear and RS-485 outputs.

Panel sizes: 48×48, 48×96, 72×72, 96×96 mm
Input types: K, E, J, R, S, B, N, T, PT, CU; 4-20 mA; 0-10 V
Default input: Type K, changeable in the menu
Output forms: Relay, SSR drive, PID 4-20 mA or 0-10 V, linear 0-10 V or 4-20 mA