# Innovations in Wheat Bread: Using Food Industry By-Products for Better Quality and Nutrition
## 4 Head Quality
### Texture
During the 72-h storage period, an increase in hardness and crumbliness was observed, manifested by a decrease in cohesiveness and springiness, which are typical indicators of bread staling. However, it should be noted that the changes in individual characteristics were not uniform. While the increase in hardness for bread with a 15% addition of defatted olive pomace was 45%, the decrease in cohesiveness and springiness was approximately 15% and 7.5%, respectively. These changes result from processes occurring during bread storage, such as starch retrogradation, gluten dehydration, amylopectin recrystallization, and the transition from a rubbery to a glassy state of the protein network. A general note on comparing the results of individual research studies should be highlighted. Difficulties arise when comparing results from different studies due to the lack of specification of all key Texture Profile Analysis (TPA) measurement parameters and the use of various measurement conditions. These conditions include different compression rates (e.g., 1 mm/s, 3 mm/s, 5 mm/s, or 10 mm/s) and varying compression levels (e.g., 25%, 40%, 50%). In some research studies, there is also an absence of a strictly defined time after which the bread texture analysis was conducted, as well as specified bread storage parameters like temperature. Due to significant texture changes occurring during bread storage, especially in the initial period, this makes it challenging to make more accurate comparisons between results concerning the use of different additional raw materials. Significant differences in the application of individual additives are also influenced by variations in the dough preparation and bread baking process. This includes the degree of comminution of individual ingredients, fermentation time, and the use of other additives in addition to the primary ingredient and supplement (discussed by-products), which also affect the bread's characteristics. Variations in the baking process itself, such as time and temperature, are also essential factors. \begin{table}
\begin{tabular}{l l l} \hline \hline
**Material and Level of** & **Effects** & **Reference** \\
**Supplementation** & **-Decrease in loaf volume and specific volume** & \\ \cline{2-3}  & -Darkening of crumb color; the color shifts towards red and blue hues** & \\ \cline{2-3}  & -Increase in hardness with the level of supplementation and storage time & \\  & -No significant changes in springiness and cohesiveness & \\  & -Decrease in overall acceptability at 10\% supplementation & \\ \hline \hline \multirow{3}{*}{Wine grape pomace powder (without grape seeds) 5 and 10 g/100 g} & -Decrease in load volume and specific volume & \\  & -No significant changes in moisture content and baking loss & \\ \cline{2-3}  & -Increase in firmness & \\ \cline{2-3}  & -No significant impact on overall acceptability (despite significant changes & \\ \cline{2-3}  & -In individual characteristics) & \\ \hline \hline \multirow{3}{*}{Wine grape pomace powder 6; 10; and 15\%} & -Decrease in volume and specific volume & \\  & -Darkening of crumb color; the color shifts towards red and blue hues & \\ \cline{1-1}  & -Increased in firmness & \\ \cline{1-1}  & -Significant differences were observed for all sensory attributes, except for & \\ \cline{1-1}  & yeast flavor, salty taste of the crumb, and crust thickness. & \\ \hline \hline \end{tabular}
\end{table} 
Table 2: Effect of selected by-products on wheat bread quality and sensory characteristics.