effect of adding corn malt on quality and shelf life of barbari bread

introduction: low quality and short shelf-life are the most important reasons for bread waste. statistics show that each iranian person consumes about 150 kg bread annually, but the low quality of bread and public discontent, would resultin 30 percent waste of traditional breads. previously barley malt was used as an additive to improve the quality and shelf life of bread (including barbari bread). the most common type of the malt used in the world is barley malt. this is because of the utilization of most of the malt product in the world, including to produce beverages based on malt, particularly alcoholic and non-alcoholic onesand considering that the malt made from barley grains has the best quality among the other cereals to produce these products.therefore, discussion on other malted cereals would be find less in the literature especially corn malt (which has not a good quality to produce malted beverages). on the other hand, corn is the main cereal widely consumed in the world after wheat and rice. the purpose of this study was to produce barbaribread usingcorn malt (powder or extract) as an additive to increase shelf-life, volume and softness, as well asimprove the sensory characteristics (staling, total appearance, softness, texture, brain color, crust color, crust appearance, flavor and odor). materials and methods: for this purpose, bakery flour with 85% extraction rate, dent corn (zea mays var. indentata), saccharomyces cerevisiae as an active dry yeast, malt extract or powder and other additives, used in the formulation of barbari bread. to evaluate the sensory characteristics, the bread samples were analyzed by 15 trained referee. the results were based on a factorial arrangement with two factors completely randomized design that the first factor is type of corn malt (powder or extract) and the second one is amount of corn malt (in four levels of 0, 0.5, 1.0 and 1.5 percent) was evaluated. results & discussion: the resultsshowed that the treatment with 1.5 percent extract corn malthas the highestspecific volume(with an average of 4.5) and thetreatment with 1.5 percent powderhas the lowestspecific volume(with an average of 3.67). and just the treatments with 1 and 1.5% malt extract in compared with the control sample showed significance differences (p<0.05). after 48 hours of baking time, firmness level of samples texture with 1 and 1.5 percent corn malt extract was less than the firmness level of treatments containing similar percentages of malt powder and control samples during 2 hours after baking. less firmness in the breads with malt extract, resulting from more effective in converting starch into dextrin which reduces the power of starch inflation and hardening of the bread. also according to the test results of texture analyzer, the samples with 1.5% malt extract have the highest elasticity ranged between 2 and 48 hours after they baked. also about the sensory characteristics in most cases including texture, crust appearance, odor and total appearance of treatment with 1.5% and after it treatment with 1% malt extract obtained the highest score from 15 evaluators (p<0.05). it should be mentioned that in cases in which treatment with 1.5% extract malt did not get the first rank of mean score, get the second or third of it with slight differences. the analysis evaluation results about staling within 48 hours after baking showed that there is no significance differences between the treatment with powder and the treatment with extract malt (p<0.05). so that the extract malt treatments score was about 4.37, which means that the treatments after 48 hours of baking time were between fresh and relatively fresh, but the powder type was relatively staling. about the amount of malt, although no significance differences between 1 and 1.5 percent treatments (p<0.05), however the score of treatments with 1.5% malt were a little higher than the 1%, and they achieved the highest score. conclusion: malt fiber composition of the samples with proportional absorption of water, prevents the moisture waste that is one of the factors which it does not done can cause firmness and staling of bread. on the other hand alpha-amylase enzyme reduces the bread firmness that this effect observes over time much more than in zero time. compared to other treatments, control treatment acquired the worst results in most of the tests. overall, considering that there was not significance differences between treatments with 1 and 1.5 percent extract corn malt often economically can be recommended treatments with 1 percent extract as an optimal treatment. based on the results of this investigation and according to the little application of corn malt in the world, corn malt can use in extract or powder form as an effective additive in formulation of barbari bread (as a traditional bread in our country that widely used).