Effects of sourdough on improving the textural characteristics of microwave‐steamed cake: A perspective from dielectric properties and water distribution

Abstract

A sourdough combined with microwave heating method was adopted to make steamed cake (SSC), the dough yield, fermentation time and additive amount of sourdough were optimized by Response Surface Methodology (RSM) to obtain microwave-steamed cake (MSSC) with high-quality attributes and then the potential mechanism of sourdough on the improvement of the MSSC texture was investigated. The addition of sourdough with the optimized parameters could greatly improve the specific volume, porosity, hardness, and chewiness of MSSC, which was mainly related to changes in dielectric properties and water distribution. The results of dielectric properties confirmed that sourdough increased the dielectric properties of the system during microwave heating, affecting the microwave heating characteristics. And the changes of water states and distribution by T 2 relaxation analysis showed that sourdough restricted water mobility during heating and facilitated the retention of water trapped in MSSC. Additionally, the scanning electron microscopy (SEM) images indicated that sourdough weakened the gluten network structure, and triggered a looser and smoother microstructure.

Improvement of microwave reheating uniformity for baked pancake from dielectric properties and heating mechanisms

“…Then the water freedom degree rose as MR, increasing the dielectric. The ε ′ and ε ″ fell after around 40 s, likely because the water evaporated from the BP, reducing the amount of water with a high freedom degree (Wu et al, 2020). Furthermore, the BP structure loosened and air entered the spaces between each layer, lowering the dielectric characteristics (Wu et al, 2020).…”

“…The inside layer of the BP had the same pattern as the outer layer (Figure 2d,f). Na + and Cl − from salt reacted strongly to microwaves, improving the dielectric characteristics of the material (Llave et al, 2016; Wu et al, 2020). Sugar, on the other hand, did not provide polar molecules; rather, it bound water molecules, reducing their freedom degree (Wang et al, 2011).…”

“…The heat from the microwave and infrared caused part of the immobilized water to move into the tightly bound water, indicating a change in the condition of the immobilized water. During reheating, processes like starch pasting and protein denaturation led part of the T 21 water molecules to bond with the starch‐gluten network to produce bound water, causing the T 21 peak to shift toward the origin (Fan et al, 2020; Wu et al, 2020). For MR‐BP The T 22 and T 23 peaks were also mixed and their area sum was increased after MR.…”

Statistical Approach to Potentially Enhance the Postbiotication of Gluten-Free Sourdough

“…A stable matrix able to ensure the L. curvatus viability during storage was optimized by RSM, being successfully used in the sourdough technology [76]. Moreover, the variation of the dough yield between 175-225 was statistically studied to conclude that this factor positively affects the textural characteristics of a sourdough cake [77]. Sourdough bread's physicochemical and textural properties (viz.…”

Uses of the Response Surface Methodology for the Optimization of Agro-Industrial Processes

“…On the other hand, in secondary transformation agro-industries, the products, by-products and residuals of the first transformation are usually used as starting Uses of the Response Surface Methodology for the Optimization of Agro-Industrial Processes DOI: http://dx.doi.org/10.5772/intechopen.98283 raw materials, and in their transformation performed by microorganisms, perfectly adapted to grow and develop using these raw materials, obtaining, as a result of their microbial activity, fermented products and beverages, with beneficial nutritional and food properties. Fermented food and beverage production industries [9,10], such as yoghurt [11,12], kefir [13,14] and the manufacturing of beer [15] and wine [16], fermented sauces and condiments, such as soy sauce, as well as the production of bio-ethanol [17,18], vinegar [19,20] and some organic acids [21,22], such as citric acid [23] and lactic acid [24], are practical examples of these agroindustries, where microorganisms and enzymes carry out the transformation of raw materials to product.…”