Perforated polythene bags are plastic bags with small holes punched into them. These perforations allow air to circulate, which is essential for various applications.   

Food Packaging:
Fresh Produce:
Perforated bags help to extend the shelf life of fruits and vegetables by allowing them to breathe.
Baked Goods: They prevent condensation and maintain the freshness of bread, rolls, and pastries.

Retail Packaging:
Clothing: Can be used to package delicate items like lingerie or knitwear, preventing wrinkles and static.  

Industrial Applications:
Packaging Components: Used to package small parts and components, allowing for better airflow and preventing moisture build up.

 

Bags / Polythene (Popular) / Perforated Polythene Bags

Perforated Polythene Bags: breathable protection for products that need airflow

Perforated polythene bags are plastic bags made with small holes that allow air and water vapour to move in and out of the pack. This ventilation is useful when a fully sealed bag would trap moisture or heat and lead to condensation, “sweating”, or softening of the product surface. In practical terms, perforations help reduce moisture build-up while still providing a clean, lightweight barrier for handling, storage, and distribution.

These bags are commonly used for fresh produce and certain bakery items because packed goods can continue to release moisture (and, in the case of produce, gases from respiration). Technical packaging references describe microperforation as a way to increase gas transfer beyond the base film alone, helping vent water vapour and support gas exchange for produce; they also note that condensation can still occur if items are packed too warm, so cooling before bagging is an important control step.

Perforated Polythene Bags — Helpful Guide

This guide explains the main bag types and how to match size and film thickness to your application. The products in this collection are perforated poly bags in a range of sizes and weights, including clear and white options.

1) Clear perforated poly bags (general-purpose breathable protection)

Clear perforated bags are often chosen when you want visibility of the contents while allowing moisture and warm air to escape. They are widely used for produce, bakery items that may still be warm, and for items where trapped humidity could cause surface dampness.

• 8x12x22 - 100g Clear PERFORATED Poly Bags (200x300x550mm - 25mu)
  Longer-format clear perforated bags suited to taller or bulkier items where ventilation helps reduce condensation.
• 6x12x18 - 100g Clear PERFORATED Poly Bags (150x300x450mm - 25mu)
  A versatile clear perforated size for smaller packs where airflow is still required.
• 40x63 - 250g Clear PERFORATED Poly Bags (1016x1600mm - 64mu)
  Large-format, heavier clear perforated bags designed for bigger items or liners where strength and ventilation are both important.
• 30x40 - 250g Clear PERFORATED Poly Bags (762x1016mm - 64mu)
  Mid-to-large clear perforated bags with a thicker film for improved durability.
• 22x31 - 250g Clear PERFORATED Poly Bags (559x787mm - 64mu)
  Clear perforated bags that balance visibility, airflow, and a stronger film for handling.
• 18x24 - 250g Clear PERFORATED Poly Bags (457x610mm - 64mu)
  Clear perforated bags in a practical size for items that benefit from ventilation and a more robust film.

2) White perforated poly bags (privacy and presentation with ventilation)

White perforated bags provide a more opaque appearance while still allowing airflow. They can be useful where you want a cleaner presentation, reduced visibility of contents, or a consistent look across packed items, while still managing moisture build-up.

• 18x29x39 - 120g White PERFORATED Poly Bags
  White perforated bags for applications needing ventilation with a more discreet appearance.

Case study: reducing condensation in packed goods

A common packing issue is moisture collecting inside a bag after packing, especially when items are packed warm or when the product naturally releases moisture. In produce, respiration continues after harvest and can change the atmosphere inside a package; in bakery, residual heat and steam can soften crusts and create droplets on the inside of the film. Perforated bags help by providing a pathway for water vapour to escape rather than being trapped against the product surface.

In one typical workflow, a packer noticed that sealed bags were developing visible condensation during storage and transport. By switching to perforated bags and tightening the pack-out process (allowing items to cool and surface-dry before bagging), the amount of internal moisture reduced and the packed goods arrived with a drier surface. Packaging literature also notes that condensation can still occur if items are packed too warm, and that water can block perforations, so process control (cooling and drying) remains important alongside bag selection.

How to choose the correct perforated poly bag

Step 1: Decide whether you need ventilation (perforated) or moisture retention (non-perforated)

Choose perforated bags when trapped moisture is the main problem (for example, items that “sweat”, release steam, or need to breathe). If your priority is retaining softness or preventing moisture loss, too much ventilation can accelerate drying and staling. Packaging references for bakery note that perforation is most helpful when the goal is to let steam escape and reduce sogginess, whereas fully sealed bags can be better when moisture retention is the priority.

Step 2: Select the right size (allow space without excessive empty volume)

Measure the product’s width, height, and depth (or stack height) and choose a bag that fits without stretching the film. A bag that is too tight can stress seams and perforations; a bag that is far too large can allow the contents to shift and may not present neatly. For bulky items, consider longer or wider formats such as 8x12x22 or larger sizes like 30x40 and 40x63.

Step 3: Choose film thickness for handling strength

Film thickness is commonly specified in microns (µm). Thicker films generally provide improved puncture resistance and durability during handling, while thinner films can be more flexible. In this collection you’ll see examples such as 25µm on smaller clear perforated bags (e.g., 6x12x18 and 8x12x22) and 64µm on larger clear perforated bags (e.g., 18x24, 22x31, 30x40, 40x63). Thickness affects strength, but ventilation is primarily controlled by the perforation pattern.

Step 4: Consider the product’s moisture and gas behaviour

Fresh produce continues to respire after packing, and technical sources describe microperforation as a method to increase oxygen and carbon dioxide transfer beyond the base film alone. Because respiration rates vary widely by produce type, the “right” level of perforation is product-specific rather than universal. If you are packing produce, it can be helpful to trial a small run and check for condensation, odour, and product condition after typical storage times.

Step 5: Control pack-out temperature and surface moisture

Even with perforations, packing items while they are still warm can create condensation as the air inside the bag cools. Packaging references note that condensation can interfere with gas exchange if water blocks holes, so cooling and surface-drying before bagging is often the first improvement to make. Perforated bags then provide ongoing ventilation during storage and transport.

Common applications and practical tips

Fresh produce

• Use perforated bags to vent water vapour and support gas exchange for produce that continues to respire after packing.
• Check the product after storage: look for excess moisture, softening, or off-odours, and adjust bag size/thickness or handling steps accordingly.
• Avoid packing wet produce; remove surface water where possible to reduce condensation risk.

Bakery items

• Perforations can help steam escape from warm bakery items, reducing internal condensation and helping crusts stay less soggy.
• If the goal is to keep products soft and prevent drying, excessive ventilation may not be suitable; consider the balance between moisture retention and condensation control.

Industrial and general packing

• Perforated bags can be useful for parts and components where airflow helps reduce moisture build-up during storage.
• Choose thicker films for heavier or sharper items to reduce punctures and tearing during handling.

Q&A