Desenvolvimento e caracterização físico-química, microbiológica e sensorial do pão transmontano com azeitonas verdes descaroçadas do tipo “alcaparras”

Abstract

Bakery products are fundamental to the diet of worldwide, being the main ingredients flour, drinking water and ferment or yeast. Wheat is the cereal most used worldwide. However, rye is increasingly being consumed, due to being a rich source of fiber, which has several health benefits. In addition, the production of new types of bread with other ingredients have been found due to the increasing demand for new products by the current consumer more aware and concerned about his health. Considering this fact, the main objective of this study was to develop and characterize in terms of physicochemical, microbiological, antioxidant and sensory properties, one Transmontano bread made with pitted green olives called "alcaparras". It was intended to follow the traditional recipe of Transmontano bread, associating three products highly appreciated in this region, namely bread, "alcaparras" and olive oil. In order to achieve the above mentioned objectives two assays were conducted. Initially it was only used wheat flour and subsequently rye flour and olive oil were added, having been used different percentages of "alcaparras". In both trials, the prepared breads were analyzed in terms of color, size, pH, ash, fat, protein, fiber and salt, as well as in microbiological terms (mesophiles, yeasts and molds) and in relation to their antioxidant properties. Sensory analysis was also performed; however, this was only performed in the second assay. In the first experiment breads were prepared with wheat flour and 0, 3, 5 and 7% (m/m) of "alcaparras", which were stored at 25 °C for 4 days, that were analyzed every two days. The breads with higher percentages of "alcaparras" had the lowest pH values and the highest values of salt and ashes. As expected, the bread with the lowest percentages of "alcaparras" had the lowest fat values. Taking into account the microbiological analyses it was found that the highest values for mesophiles, molds and yeasts were obtained at the end of storage, resulting in unsatisfactory values on the fourth day. In relation to the antioxidant activity, it was found that the breads with the highest percentages of "alcaparras" showed higher total reducing capacity, blocking effect of DPPH free radicals and reducing power. Subsequently, in the second trial breads with wheat and rye flours, and with 0, 7 and 14% (m/m) of "alcaparras" without adding olive oil, and 0 to 7% (m/m) "alcaparras" with added olive oil, were prepared that were subsequently stored at 25 °C and analyzed at 0, 2 and 5 days. The breads with "alcaparras" presented again the lowest pH values and the highest levels of salt and ashes. In relation to fat, lower contents were determined in the breads without olive oil in relation to breads with olive oil, having the addition of olive oil increased a significantly (approximately 4 times) the fat content. It was found, as in the first trial, that the breads with higher percentages of "alcaparras" showed higher antioxidant activity. As the results for the breads with 0 and 7% "alcaparras" with and without addition of olive oil were similar, it could be stated that the addition of olive oil did not affect the overall total reducing capacity and the blocking effect of DPPH free radicals, however, the olive oil exerted a inhibitory effect on the growth of microorganisms. Nevertheless, after five days it was observed growth of molds and yeasts. In sensory terms, after cooking, all breads had high rating in terms of overall assessment, having the bread with olive oil and 7% (m/m) of "alcaparras" the highest score, being the preferred. In conclusion, wheat bread with "alcaparras" and rye bread with "alcaparras" and olive oil are a promising product to be marketed. However, more studies are needed to increase its shelf life.