Influence of modified atmosphere packaging and xanthan gum on shelf life of sangak bread

In this study, the effects of xanthan gum on shelf life of Sangak bread were investigated. The gum was added to the formulation at 0.5 and 1%)w/w) concentration. As a control, no gum added formulations were used. Wheat bread samples were packaged in polyamid/ polyethylene bags with different gas combinations. Two gas concentrations tested included: air (control), and 100% CO2. All packaged bread samples were stored at 25°C for 15 days. During storage, quality and microbial features of bread such as moisture, texture, density, mold and yeast count were assessed at intervals of three days. Statistical analysis of the results of Sangak bread quality characteristics during storage revealed that, the gas in headspace of package did not significantly affect the product density and moisture content, while shear stress, maximum force and the microbial load of the samples were thoroughly impressed by the atmosphere of the package. So that with carbon dioxide, the growth of mold and yeast was more limited. Also was observed all product quality characteristics changes significantly during storage time. So that the reduced moisture and density were observed up to 12th day. Conversely hardness, shear stress and microbial load increased during the storage period. The breads containing 1% xanthan showed the lowest maximum force, shear stress and the microbial load and the highest moisture all over the storage period. Bread samples containing xanthan gum at 0.5% level showed the highest density during their storage time. In bread packaged with 100% CO2, the lowest slope of the maximum force curve and shear stress versus storage time were recorded by treatment having 1% xanthan.