01 Aug 2021 Maize packaging: appreciating the paper bag’s benefits

When consumers see the ubiquitous 2.5kg maize meal bags on supermarket shelves and in their homes, many may not know the fascinating journey this packaging has made over the years.

According to an interesting article in PPM magazine, SA’s superb trade journal for the packaging and printing industries, that the printed cotton bag was the predominant pack for maize and flour in the 1960s.

At that time, South Africa’s measurement system was still imperial, and the most popular size was five pounds. Five of these bags were packed into a hessian baler after a very labour-intensive and slow filling process. The open mouth bags were handheld under a gravity-fed filling spout, then weighed and stitched closed.

Ten years later, following European trends and significant developments in high-speed fillers, the block-bottom self-opening paper bag started replacing the cotton bag.

The paper bag was not laminated, allowing the contents to breathe and cool down without condensation within the pack, eliminating product leakage (dust that invited weevils)! It could also stand upright for superior shelf presentation and its print quality was better – a trend that has continued to improve with flexographic technology.

The adoption of the block-bottom self-opening paper bag was an integral part of the high-speed filling system, developed by the likes of German manufacturer Fawema in the early 1970s, which became extremely popular in the South African milling industry. Fawema’s oldest machine, still running today, was installed in 1973.

The filling systems’ development covered three main areas – accurate dosing fillers, vibrating tables to settle the product in the bag and sealers to close the bag – and they were fully automatic by the early 1980s.

The next time you spot a maize bag in-store, I hope you can appreciate how the filling process has evolved from a clumsy, handheld, labour intensive cotton bag to today’s automated, high-speed paper version.

Authored by Clive Glover, monthly columnist in PPM. from the June 2021 issue. He attributes these insights into this fascinating evolution to doyen of the South African packaging industry, Andrew Marthinusen, and Colin Wootton and John Hancock, who were both senior executives in the Premier Milling Group before retiring.