Volume change of bread and bread crumb during cooling, chilling and freezing, and the impact of baking

Determination of pizzas quality and acceptability by physic-mechanical tests

The growing need for developing more efficient and sustainable technologies for the processing of bakery products leads to the need for replacing the current subjective methodology by an instrumental method to evaluate the quality of these products. In this work, relevant physic characteristics that define the quality and acceptability of pizzas were identified, and instrumental methods were established to evaluate them. Cooking quality of the pizza base was established through rapid visco analysis and scanning electron microscopy. The physic attributes considered of the pizza base with and without toppings were final cooking temperature, specific volume, water content, color, and texture. Aiming to validate the applicability of the instrumental methods, we prepared well-accepted pizzas, using three different oven technologies, and carried out a sensory test with 60 non-trained panelists. We observed that the proposed method is sensitive enough to identify differences in the quality of pizzas produced by the oven technologies. However, those variations were not enough to be recognized by participants of the sensory panel. The values of pizza attributes obtained in this work could be used as a baseline of comparison for pizzas produced by new and more efficient cooking technologies.

SUPPLEMENTARY INFORMATION

The online version contains supplementary material available at (10.1007/s13197-021-05148-8).

Impact of selected baking and vacuum cooling parameters on the quality of toast bread

Vacuum cooling of baked goods can deliver many advantages in terms of product quality and productivity, such as higher volumes and shorter cooling times. However, the associated high costs and the need to adjust baking protocols are of relevance and more information is needed. This paper examines the influence of two main baking protocol parameters on the quality of toast bread, i.e. oven temperature and baking time reduction. Resulting toast bread characteristics including specific bread volume, concavity, browning index, crust and crumb hardness and a_w-value were analysed as well as process-dependent core temperature and water loss. In order to compensate for water loss during vacuum cooling and still achieve optimal toast bread quality, a final bread core temperature of 98 °C at the end of baking gave best results, regardless of oven temperature. It was further shown that cooling time can be reduced by a factor of 10 if the baking protocol is optimally adjusted, hinting at a huge potential to increase productivity for industrial applications. In summary, it can be stated that vacuum cooling requires a tailored reduction in baking time in order to compensate for water loss from vacuum cooling while retaining sufficient structural cohesion to resist deformation of the bread.