What Is a Food-grade FIBC?

A food-grade FIBC is a bulk bag whose fabric, liner, sewing thread and handling route are all controlled so that the bag does not introduce contamination into the material it carries. In practice that means virgin polymer with no regrind in the fabric or liner, a liner converted in a segregated area, and a documented chain of custody from extrusion to final packing. Food-grade is a property of the production route, not a certificate attached to a bag.

Why the definition is process-based

Contamination in bulk bags comes from four sources: residual additives in the resin, dust and fibre released by cutting and sewing, shared handling equipment, and storage before dispatch. A bag can be built from compliant polymer and still fail a packer’s incoming check because it was cut on a bench that also handled coloured or recycled fabric. Buyers who know this ask about the process rather than the polymer alone: which resin grade, which extrusion line, whether the liner is blown film or flat film, whether the cutting and sewing area is separated, and how finished bags are packed before they leave the plant.

What actually changes in production

• Fabric: virgin homopolymer polypropylene, no regrind, with UV stabiliser added only where the bag will be stored outdoors.
• Liner: LDPE or LLDPE, typically 50 to 100 micron, with a seal-integrity check on a sample per batch.
• Cutting and sewing: dedicated area, covered machines, lint control, and needles and offcuts counted at the end of each shift.
• Packing: liner inside the FIBC, then a PE outer bag on a pallet, so the food-contact surface is never left exposed in the yard.

QINFENG’s first-hand experience

Most of the food-contact work we run is for ingredient packers moving powders, starches, sugar and dried fruit. On those lines the failure we actually see is rarely the fabric — it is the liner. A seal that looks sound at the machine can open after a long road leg, and the bag arrives with powder sitting in the gap between liner and fabric. We now run a peel and hold check on liners before the bag is packed and keep the tested sample with the batch record. We also record the liner film roll number against the bag serial, because when a packer does report a problem, the first questions are always which roll and which shift.

Where the answer changes

Food-grade in this sense does not describe the hygiene of your packing site, and it does not cover what happens after the bag leaves our plant. The answer also shifts with the product: fine powders, oily or fatty ingredients, and warm-fill applications each move the liner and seal specification. Where a market has its own direct-contact requirement, that requirement has to come from your written specification; third-party testing is arranged on request and quoted separately.