rope spoilage in bread

Rope spores are a bacteria which causes spoiling in bread.

Rope Spoilage

What is Rope Spoilage?

Rope spoilage – also referred to as ropey bread or rope – is a bacterial spoilage of bread caused various species of Bacillus. 1 Rope spoilage initially demonstrates as an unpleasant fruity odor followed by a discolored, sticky or soft breadcrumb.

Rope spores are heat resistant and must be prevented through good manufacturing practices, process control, hygiene standards and chemical preservatives.


Rope spoilage initially exhibits 12 – 24 hours after a loaf has been baked and is marked by fruity odor, sometimes compared to the scent of rotting pineapple or melon. The odor is followed by a discolored, sticky or soft breadcrumb. The spoilage will ultimately appear as thin, web like strands when the baked item is pulled apart, often accompanied by a bitter flavor.Bread adulterated by rope spoilage is rendered inedible and ultimately disposed of.


Ropy bread is primarily caused by Bacillus subtilis, however, B. licheniformis, B. megaterium and B. cereus are also capable of causing rope. Bacillus subtilis is a gram-positive, aerobic, spore-forming soil bacterium found in soil, dust, water and even air.3  Spore forming bacteria are able to form endospores even when environmental conditions are not favorable to growth. Endospheres of the Bacillus species of bacteria known to cause rope spoilage contaminate raw materials such as flour and yeast, as well as dehydrated ingredients such as powders, spices and bread improvers, are heat resistant and develop rapidly.4 While no visible trace of spore contamination is noticed in dehydrated ingredients, even the presence of a single spore can lead to spoilage during the storage of products. The presence of certain Bacillus strains may contribute to a mild form of food-borne illness. Losses from reduced shelf life and spoilage of baked goods can have a significant and negative economic impact on bread producers.5

Rope spoilage prevention efforts center around manufacturing processes, hygiene and storage standards to reduce moisture and the use of chemical preservatives, such as propionic or sorbic acids, or their salts.6

FDA Regulations

For more information on FDA Regulations for preventing food spoilage in retail food production, please visit:


  1. Pepe, Olimpia, Giuseppe Blaiotta, Giancarlo Moschetti, Teresa Greco, and Francecso Villani. “Rope-Producing Strains of Bacillus Spp. from Wheat Bread and Strategy for Their Control by Lactic Acid Bacteria.”American Society for Microbiology. N.p., 29 Nov. 2002.
  2.  Rumeus, Iurie, and Maria Turtoi. “Influence of Sourdough Use on Rope Spoilage of Wheat Bread.”Journal of Agroalimentary Processes and Technologies 19.1 (2013): 94-98.
  3. Tam, Nguyen K. M., Nguyen Q. Uyen, Huynh A. Hong, Le H. Duc, Tran T. Hoa, Claudia R. Serra, Adriano O. Henriques, and Simon M. Cutting. “The Intestinal Life Cycle of Bacillus Subtilis and Close Relatives.”Journal of Bacteriology. American Society for Microbiology, Apr. 2006.
  4.  Martínez Viedma, Pilar, Hikmate Abriouel, Nabil Ben Omar, Rosario Lucas López, and Antonio Gálvez. “Inhibition of spoilage and toxigenic Bacillus species in dough from wheat flour by the cyclic peptide enterocin AS-48.” Food Control 22.5 (2011): 756-761.
  5. Sorokulova, I.B., O.N. Reva, V.V. Smirnov, I.V. Pinchuk, S.V. Lapa, and M.C. Urdaci. “Genetic diversity and involvement in bread spoilage of Bacillus strains isolated from flour and ropy bread.” Letters in Applied Microbiology 37.2 (2003).
  6. Saranraj, P., and M. Geetha. “Microbial Spoilage of Bakery Products and Its Control by Preservatives.”International Journal of Pharmaceutical & Biological Archives3.1 (2011): 38-48.