Variation in nutritional properties of multi-seed bread according to pre-baking and freezing conditions.
The aim of a recent study, carried out by a team of Spanish researchers (Miranda-Ramos & Haros, 2023), was to analyse the effects of pre-baking, freezing and subsequent storage (at -20°C for 90 days) on the quality of multi-seed bread (quinoa, amaranth and chia flours).
The results were compared to the control product made only with wheat flour processed under the same conditions. The tests demonstrated that the technological characteristics and nutritional properties were not altered, except for a slight rise in crumb firmness values and slightly lower chewiness. In addition, the essential amino acids content did not decrease during bread storage, resulting in significantly higher content in multi-seed samples than in the control product.
In the multi-seed product, the levels of lysine, valine and leucine, respectively, exceeded the control product by 50, 10 and 5%. Minimal difference in colour was registered between the control and the multi-seed products, which could not be perceived at the sensory level. After frozen storage, the amylopectin retro-gradation enthalpy was up to 33% lower in multi-seed bread than in control bread, possibly due to the action of polyunsaturated fatty acids and the soluble fiber content present in the multi-seed product.
In conclusion, the authors point out that the results so far are very promising for the formulation of healthy breads suitable for modern consumption. However, further research is necessary to define the sensory aspects and consumer acceptance of the bread thus produced.
Dielectric spectroscopy for the development of microwave sensors to be used during the production of Carasau bread.
Microwave sensors are an attractive, cost-effective alternative for monitoring the quality of small-scale food products during their processing cycle. In this context, the aim of a recent study, carried out by a group of Italian researchers (Macciò et al., 2023), was to use dielectric spectroscopy to measure the permittivity of Carasau bread samples in a frequency range between 0 and 8.5 GHz.
The results show that the dielectric properties of Carasau bread doughs strongly depend on the water content. An increase in water quantity tends to increase the bounded water fraction at the expense of the free water fraction; moreover, an increase in electrical conductivity was observed for increasing water content in the samples.
The permittivity, on the other hand, was slightly affected by the composition of the product (with respect to water, salt and yeast content). In conclusion, the proposed approach can be used to design microwave sensors for investigating the composition of Carasau bread doughs during their production process.
References:
K.C. Miranda-Ramos and C.M. Haros, LWT – Food Science and Technology, 187, 2023, 115340; Macciò et al., Foods, 12, 2023, 1-19.
