When it comes to food safety, what happens behind the scenes is just as important as what ends up on our plates. From fresh produce and dairy products to frozen ready meals, keeping food safe, fresh, and full of flavour relies heavily on cold storage. However, it’s not just about keeping things cold - it’s about doing so consistently and correctly.

At Rayflex, we know that the right equipment can make all the difference in maintaining cold chain integrity. That’s why we supply Coldstore-grade PVC strip curtains that help cold storage facilities operate efficiently while meeting the strict demands of food safety standards. But how does cold storage actually work - and why should it matter to every business handling perishable goods?

What is cold storage?

Cold storage refers to temperature-controlled environments designed to keep perishable goods at specific low temperatures to extend shelf life and maintain safety standards, particularly for transit purposes. These environments range from small walk-in chillers to vast industrial freezers used in food production, logistics, and retail distribution.

Unlike standard storage rooms, cold storage units are insulated and climate-controlled to ensure stable temperatures - often between 0°C and 5°C for refrigerated goods and as low as -18°C for frozen products. Maintaining these conditions consistently is critical to preventing the growth of harmful bacteria and ensuring compliance with food safety regulations.

Why is cold storage important for food safety?

The significance of cold storage in food safety can’t be overstated. Proper temperature control is one of the most effective methods for preventing foodborne illness and maintaining food quality. Indeed, The Food Standards Agency reports that improper temperature control is one of the leading causes of food poisoning incidents in the UK, highlighting the critical role that cold storage plays in public health protection. When perishable foods are kept at suitable low temperatures, microbial growth slows dramatically, extending shelf life while preserving nutritional value, appearance, and taste.

How cold storage prevents contamination and spoilage

Bacteria that cause foodborne illnesses, such as Salmonella, Listeria, and E. coli, thrive at temperatures above 5°C. In fact, most harmful bacteria multiply most rapidly between 5°C and 63°C - this is known as the 'danger zone'. So, by storing food in chilled or frozen environments, cold storage facilities are able to slow or stop the growth of these microorganisms. Naturally, this not only helps to maintain product quality but, more importantly, also reduces the risk of contamination, spoilage, and waste. However, slowing microbial growth is not the only way cold storage prevents contamination and spoilage. It also:

  • Reduces enzymatic reactions: The natural enzymes present in foods that cause ripening and eventual spoilage work much slower at lower temperatures.

  • Moderates moisture retention: Proper humidity levels in cold storage prevent foods from drying out while also limiting the moisture that could encourage mould growth.

  • Prevents oxidation: Lower temperatures slow oxidative processes that cause rancidity in fats and oils, as well as nutrient degradation.

By addressing these factors simultaneously, cold storage creates an environment where food stays fresher and safer for significantly longer periods than would otherwise be possible.

How is temperature controlled in cold storage facilities?

Modern cold storage facilities use sophisticated systems to maintain precise temperature conditions. The primary components typically include:

  • Refrigeration units: Industrial-grade compressors, condensers, and evaporators work continuously to remove heat from the storage space.

  • Insulation: High-performance insulating materials in walls, ceilings, and floors prevent heat transfer from the external environment.

  • PVC strip curtains: High-quality PVC strip curtains, like those provided by Rayflex, play a crucial role in temperature maintenance by creating effective thermal barriers at doorways and between different temperature zones. These flexible, overlapping strips allow for efficient movement of goods and personnel while minimising cold air loss and warm air infiltration - a simple yet remarkably effective solution that dramatically reduces energy costs and temperature fluctuations.

  • Airflow management: Strategic air circulation ensures uniform temperature distribution throughout the storage area, eliminating warm spots where spoilage could occur more rapidly.

  • Monitoring systems: Advanced digital sensors and monitoring equipment provide real-time temperature data, triggering alerts if conditions deviate from the prescribed range.

For larger facilities, redundant systems are often installed to provide backup in case of equipment failure, ensuring temperature integrity is maintained even during mechanical issues or power outages.

How to maintain humidity in cold storage

While temperature gets most of the attention, humidity control is just as vital – especially for fresh produce, meat, and dairy products. Too much moisture can encourage mould and bacteria growth, while air that is too dry may cause dehydration and product shrinkage. Maintaining appropriate humidity levels typically involves:

  • Humidifiers or dehumidifiers, depending on the environment

  • Proper air circulation systems, which ensure even distribution of moisture

  • Sealed environments, which minimise moisture ingress and prevent condensation.

Well-maintained humidity helps to preserve texture, appearance, and weight - all key factors in both food quality and value.

How do PVC strip curtains work?

As touched on above, one of the most effective – and often overlooked – tools for supporting temperature and humidity control is the use of PVC strip curtains and specialist chiller blinds. At Rayflex, we manufacture high-quality coldstore-grade PVC strip curtains designed specifically for cold storage environments.

These flexible barriers hang in overlapping strips, forming an effective seal that retains chilled air within the cold room while still allowing easy movement of people, trolleys, and equipment. Unlike solid doors, PVC strip curtains:

  • Provide continuous protection, sealing the space even when in use

  • Minimise temperature loss and air exchange

  • Reduce the workload on refrigeration units, saving energy and operational costs

  • Act as barriers against airborne contaminants and pests.

By preventing warm air from entering and cold air from escaping, these curtains help to stabilise the internal climate and reduce fluctuations that could compromise food safety.

In particular, our Rayflex freezer-grade PVC curtains are designed to remain flexible at sub-zero temperatures, avoiding brittleness and breakage. We also offer ribbed and antimicrobial options for environments with more stringent hygiene or handling requirements.

Browse our products across the site or get in touch with our expert team for more information. With over 50 years experience in the industry, we’ll help you find the perfect PVC strip curtain solution to suit your needs.