The most elementary and necessary part of our daily routine is the food we eat. Our health and wellbeing depends on every edible item that we consume. Be it vegetables, meat, fruits, beverages or any other stuff, quality and fitness of these consumables have far reaching consequences in our life. Thus, storage of food items is of highest priority. On the way from the raw material to the sales-ready goods, foods pass through different processing levels and processes. This results in a chain of producers, processors and dealers. No foods may ever be brought into circulation which are damaging to health or unsuitable for consumption.

Importance of Cold chains

When customers buy food, they expect that the products are of impeccable quality, and safe. In order that this really is the case, the cold chain is crucial for refrigeration-mandatory foods such as meat and sausage or dairy products. It ensures the quality and safety of foods: Legally prescribed temperature limit values may be exceeded on the way from the producer to the consumer. As the safety and quality of foods can be negatively influenced by the wrong temperature, the monitoring of the temperature of cold chain-mandatory products is a central building block in the assurance of the desired quality and marketability.

Precise Measurement Process for Superior Quality

In the monitoring of temperatures, two types of techniques are used:

  • Spot check measurement with portable temperature-measuring instruments: These can be with permanently fixed probes or with exchangeable probes, mostly when varying measurement tasks are required. This can also be conducted by using non-contact measurements using infrared thermometer.
  • Continuous data recording in which a measuring instrument with a memory remains with the goods (or in their proximity, e.g. in a refrigerated room), and records values at regular measurement intervals: Data loggers are used for continuous data monitoring.

A very precise measurement is a core temperature measurement, i.e. a penetration probe measures the temperature in the interior of the refrigerated goods. However, for many products, this means destroying the packaging and the product. To avoid this, a 3-level process has proven its worth in practice:

  1. First, an infrared measuring instrument is used to scan the surface, e.g. yoghurt pots. Infrared measuring instruments are suitable for obtaining a rapid overview of the temperature of the products. If the temperature is clearly within an acceptable range, the test is finished.
  2. If the temperature of some products is outside the prescribed range, then a contact probe is inserted between two products, and the temperature is measured there. If the temperature is now within the limit values, then the previous infrared measurement showed merely a warming of the outside.
  3. If the temperature is still outside the prescribed range, then for verification purposes, a penetration measurement is carried out on one or more pots. The probe is inserted into the foodstuff, and measures the core temperature.

Measurement Necessary at Every Step

Product Processing and Storage
Fresh and frozen goods whose preservation and quality are dependent on permanent refrigeration require an uninterrupted cold chain to protect them from spoiling for as long as possible.

For refrigeration-mandatory foods, legal stipulations regulate the temperature zones which must be adhered
to during the cold chain.

  • Deep-frozen meat and fish need to be continuously chilled through to -18 °C.
    • Max temperature required for fresh meat is +4 °C, for milk and dairy products is +8 °C.
    • For fruits and vegetables, a temperature range of +1 to +12 °C is applicable.

Food transport

Here the focus is on the transfer of liability. For the purposes of traceability, the freight forwarder must be able to prove that the cold chain was not interrupted during transport.

Measurements carried out during transportation call for special data logger requirements:

  • Limited package space necessitates a flat design
    • Easy to use
    • The logger should only record transport-relevant data
    • Alarms must be easy to recognize, to initiate control measures in time.

Recommended instrument: Transport data logger testo 184

Incoming Goods

 Incoming Goods is the location at which foods are delivered. In the context of food safety, fresh food and frozen goods deserve special attention here, because adherence to the cold chain is prescribed for them. Different temperature ranges apply for each of these product groups (according to DIN 10508):

  • Deep-frozen foods: -18 °C
    • Minced meat: +2 °C
    • Fresh fish (in ice): +2 °C
    • Fresh poultry: +4 °C
    • Processed fish (marinaded, soured and smoked): +7 °C
    • Other perishable foods, including e.g. baked goods with incompletely baked filling or covering, freshly cut salads and delicatessen salads: +7 °C
    • Pasteurized milk: +8 °C
    • Butter, cream cheese, soft cheese: +10 °C

The handover of goods generally takes place in the loading bay. Immediately after the supplier’s arrival, the temperature is measured here either on the loading platform or directly in the truck.

Recommended instrument: Non-contact infrared thermometer testo 831 & data loggers

Refrigerated Counters, Shelves etc.

In sales outlets, products in need of cooling are stored either in refrigerated units (shelving, displays, counters) or in deep-freezers.

Refrigerated products: The temperature of sealed products is usually measured without contact. For meat, sausage and cheese, a penetration measurement is normally carried out. The permitted temperature range here is typically between+2 and +10 °C.

Deep-frozen products: Non-contact measurement or measurement “betweenpackages”. The permitted temperature range here istypically between -20 and -18 °C.

Refrigerated shelving, counters: Data loggers are installed in refrigerated shelves or counters close to the air intake, as the air temperature is warmest here (should still be under +10 °C). In deep-freeze units, a measurement is taken ideally between the packaging (e.g.spinach, pizza, ice cream).

Refrigeration and deep-freeze rooms are usually monitored using the “semi-stationary” method, i.e. a data logger is fixed to a wall of the refrigerated room, where it measures and records the air temperature.

Recommended instrument: Non-contact infrared thermometer testo 831& data loggers

Safe Food Safer You

Refrigeration prolongs the lifetime of foods and hinders germ growth. The adherence to the cold chain serves the quality and safety of foods. There are various ordinances, norms and standards about the cold chain. They stipulate, among other things, that proof of temperature compliance is a mandatory requirement. HACCP describes the implementation of process-oriented hazard analyses. Where risks occur, control points must be set-up and correction measures must be taken. Testo India provides the best solutions and precise instruments that comply to several necessary norms and ensure the safety of the society.

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