            !       ___________________________________________ Corresponding author: email: maria.turtoi@ugal.ro               !" Faculty of Food Science and Engineering, University Dunarea de Jos of Galati 111 Domneasca St., 800201 Galati, Romania  #$ % &’$#(  $)  &’$# ______________________________________________________________________________________  Rope spoilage is a bread disease which consists in bacterial decomposition of the bread crumb. Spoilage organisms are heatresistant spores of bacteria Bacillus subtilis, B. licheniformis and B. pumilus which survive the baking process. The aim of this paper is to study the influence of sourdough addition on characteristics of wheat bread and on occurrence of rope spoilage after baking and storage. Ropiness occurs in nonacidified breads and consists in breaking down bread components and leaving behind a fruity, melontype odour. Sourdough addition increases the acidity of dough from 2.0 acidity degree (control sample) to 4.3 acidity degree in this work. It improves bread quality in terms of microbiological safety but reduces bread volume and porosity as well as worsens organoleptic properties (sour taste, dense and thick crumb). The results showed the reduction of bread height from 140 mm (control sample) toward 102 mm and of bread porosity from 90.2 % (control sample) toward 70.7 % for the last sample. Ropiness was observed only in control sample after 72 hours from baking. The results confirmed the positive role of sourdough on rope spoilage prevention. : Wheat bread, rope, spoilage, sourdough, rope spores, Bacillus subtilis, wheat bread, prevention. ************************************************************************************** $  Rope spoilage is a bread disease consisting in bacterial decomposition of the bread crumb. Spoilage organisms are heatresistant spores of bacteria belonging to Bacillus genera which survive the baking process. Most important rope formers are Bacillus subtilis, B. licheniformis and B. mesentericus, also known as B. pumilus [14]. These bacteria are part of the grains microbiota and reach the flour through grinding. Sources of rope spores microorganisms in bread products are mostly present in the ingredients, especially flour and yeast. Unlike moulds that are destroyed when exposed to baking temperatures, rope spores microorganisms are able to form spores and survive the baking process, germinate, and continue to grow. Optimum growth conditions for rope formers are 35…45°C, humid environment (e.g. packed bread) and pH values higher than 5.3 [5]. Pepe et al. [6] isolated sixtyone Bacillus strains from ropy breads. These strains were characterized on the basis of their phenotypic and genotypic traits. All of the isolates were identified as B. subtilis by biochemical tests, but mollecular assays revealed that besides strains of B. subtilis, B. licheniformis, B. cereus and isolates of B. clausii and B. firmus were identified. In other research, Valerio et al. [7] examined the diversity of sporeforming bacteria isolated from raw materials and bread using molecular methods along with a rapid and innovative technology, the FTNIR (Fourier transform nearinfrared) spectroscopy. They found 13 bacterial species belonging to Bacillus (10) and Paenibacillus (3) genera. The most frequent species was B. amyloliquefaciens, found also in ropy bread. The screening test performed for rope production indicated that mainly B. amyloliquefaciens, together with B. subtilis and B. pumilus, could cause spoilage in bread, even if the last two species were represented by a low number of isolates. The Bacillus cereus group and Bacillus