Flour is often shipped from the miller to bakeries, institutions, and other bulk uses. Sizes range from 10 kg to 100 kg. One traditional construction was cheapcotton bags. These printed cotton bags were sometimes viewed ascollectables; other times theflour sack fabric was repurposed into a variety of household items.
Current practices are to use multi-wallpaper sacks. Some include a layer ofplastic film for barrier properties and insect control. Woven polypropylene bags are also used for high strength; at least one variety (Purdue Improved Crop Storage bags) also includes inner plastic bags.
Consumer packages are often bags or sacks constructed of paper.Plastic films are also used, sometimes withreclosable features.Stand-up pouches of flour have recently been introduced.[1]
A wide variety ofwheat flour are available. Flour can also be made from other grains, roots, nuts, etc.Packaging engineers andfood scientists need to understand the properties of the particular flour, intended handling and logistics systems, and desiredshelf life.[2] Package forms and materials can be matched to these needs.[3]
Testing the ability of packages to resist insect infestation[4]
Insects can be a problem. When available, a suitableinsecticide can be used; care must be used to ensure product safety. Hermetic plastic bags also help.[5][6] When insect infestation is noted, one method of stopping further growth is to freeze the sacks of flour for several days.[7]
Reuel Colt Gridley became famous in the United States in 1864 by repeatedly selling a sack of flour to raise money for wounded U.S. Civil War veterans.
Flour sack fabric has been used as a cheap source of fabrics for consumers to create their own textiles.
Printed cotton bags were sometimes viewed ascollectables.
Various place names were named after flour sacks, since they were so ubiquitous in so many cultures.Blatobulgium in Scotland, andPieniężno in Poland, for example, are possibly named after words forflour sack in different languages. The all-white tower in the old city ofRavensburg in Germany is calledMehlsack.
Reuel Colt Gridley famously carried a 50-pound bag of flour on his shoulder after losing a political bet inAustin, Nevada. The sack of flour was later auctioned off, then re-donated, then re-auctioned again and again to raise money for theUnited States Sanitary Commission during the American Civil War. Auctioning this single flour sack eventually raised more than $250,000.[8]
