Agnieszka Nawrocka

Black lime (Citrus × aurantiifolia) is a dried key lime product traditionally used in Middle Eastern cuisine, characterized by an intense sour taste, distinctive citrus aroma, and dark color. Owing to its content of dietary fiber and bioactive compounds, particularly phenolics, black lime powder (BLP) may represent a promising ingredient for food enrichment. This study characterized BLP and evaluated the effects of replacing 3–15% of wheat flour with BLP on the physicochemical, antioxidant, spectroscopic, and sensory properties of shortbread cookies. Compared with wheat flour, BLP contained higher levels of dietary fiber, ash, and phenolic compounds, with protocatechuic, p-coumaric, vanillic, and ferulic acids, as well as isovitexin and vitexin, among the predominant compounds. Increasing BLP addition increased ash, soluble and insoluble dietary fiber, total phenolic content (TPC), and radical-scavenging activity. At 15% BLP, total dietary fiber reached 10.53% of cookie dry mass, while TPC and ABTS and DPPH radical-scavenging activities were approximately 5.5-, 11.1-, and 28.9-fold higher than in the control, respectively. These compositional enhancements were accompanied by technological changes, including increased moisture content and water activity, reduced cutting force, darker and less yellow cookies, and changes in starch organization and gluten structure indicated by FTIR analysis. Overall acceptability remained comparable with the control at 3–12% BLP but decreased at 15%, with 6–9% providing the most favorable balance between sensory quality and compositional enrichment. These findings indicate that BLP can be used as a fiber- and phenolic-rich ingredient for shortbread cookie enrichment.

Considerable attention has recently been paid to the consumer demand for healthy, fortified, and vegan products. Moreover, there has been increasing interest in the reuse of food processing by-products in order to reduce the environmental impact and simultaneously valorize waste through its conversion into value-added products. In the present study, the appropriate degree of grinding the pomace from yellow watermelon cv. Janosik was based primarily selected based on the water-binding capacity (WBC) and cation exchange capacity, as these parameters are indicative of the pomace’s functionality in food applications. Next, the basic chemical composition of powdered pomace, i.e. the content of fiber, fat, protein, vitamin C, total phenolic compounds, flavonoids, and anthocyanins and antioxidant activity, were determined. The next stage of the study consisted in preparation of jelly candies supplemented with different concentrations of powdered pomace (20, 35, and 50%), citric acid (0.75 and 1%), and agar (0.5 and 1%) and assessment of their physicochemical and textural properties. The pomace was obtained from whole yellow watermelon fruits (cv. “Janosik”) that were pressed without prior peeling, meaning the material included both the edible flesh and parts of the rind. The results showed that the increase in the concentration of the powdered additive was accompanied by a decrease in the moisture content and water activity of the jellies and an increase in their pH value. Additionally, the jellies became lighter and more yellowish, as indicated by increasing values of the L* and b* parameters. In turn, textural analysis showed a significant (p < 0.05) increase in hardness, gumminess, and chewiness of the jellies with increasing concentrations of powdered pomace, citric acid, and agar. For example, hardness increased from 1598 N in the lowest supplementation (sample JC1) to 6984 N in the highest (sample JC12), gumminess from 904 to 2697 g, and chewiness from 41.7 to 122.6 N mm.

Wheat flour and durum semolina were enriched with powders from four medicinal mushrooms during dough mixing. Wheat flour and durum semolina were substituted with chaga, Cordyceps sinensis , reishi and lion’s mane powders at 3%, 6%, 9% and 12% ( w/w ). Changes in the gluten secondary structure...

Thermal analyses (TGA and DSC) were used to determine the thermal properties of gliadins and glutenins extracted from a model wheat dough fortified with flavonoids and their glycosides. As flavonoids, quercetin; naringenin; hesperetin; and their glycosides, rutin, naringin, and hesperidin, were used in amounts of 0.05%, 0.1% and 0.2%. An analysis of TGA parameters showed that samples fortified with flavonoids/glycosides led to an increase in the weight loss of gliadin. The thermal behavior of gliadins enriched in polyphenols depended on the structure and size of the added compound. The weight loss of glutenin did not change in the presence of the studied polyphenols. An analysis of the difference TGA thermograms showed that quercetin, rutin, and naringin interacted with gliadins through the OH group located at the B ring in the 4’ position. Additionally, quercetin formed chemical bonds with the polypeptide chains of glutenins. The DSC thermograms were consistent with the TGA results, which suggest interactions between gliadin and quercetin.

Due to the health benefits attributed to the consumption of phenolic acids, these compounds can be used as natural pro-health food or beverages ingredients. To improve polyphenols stability during food processing and storage, they could be encapsulated in colloidal systems e.g. via complexation...

Strawberries are abundant in essential nutrients such as vitamins, minerals, antioxidants, and dietary fiber. This study aimed to assess how partially substituting wheat flour with freeze-dried strawberry powder (in concentrations of 0, 3, 6, 9, and 12 g per 100 g-1) would affect the...

In this study, we analysed the potential use of dried strawberry leaves and calyces for the production of nanoparticles using inorganic iron compounds. We used the following iron precursors FeCl₃ × 6H₂O, FeCl₂ × 4H₂O, Fe(NO₃)₃ × 9H₂O, Fe₂(SO₄)₃ × H₂O, FeSO₄ × 7H₂O, FeCl₃ anhydrous. It was discovered that the content of polyphenols and flavonoids in dried strawberries and their antioxidant activity in DPPH and FRAP were 346.81 µM TE/1 g and 331.71 µM TE/1 g, respectively, and were similar to these of green tea extracts. Microimages made using TEM techniques allowed for the isolation of a few nanoparticles with dimensions ranging from tens of nanometres to several micrometres. The value of the electrokinetic potential in all samples was negative and ranged from −21,300 mV to −11,183 mV. XRF analyses confirmed the presence of iron ranging from 0.13% to 0.92% in the samples with a concentration of 0.01 mol/dm³. FT-IR spectra analyses showed bands characteristic of nanoparticles. In calorimetric measurements, no increase in temperature was observed in any of the tests during exposure to the electromagnetic field. In summary, using the extract from dried strawberry leaves and calyxes as a reagent, we can obtain iron nanoparticles with sizes dependent on the concentration of the precursor.

The aim of this research is to determine how phenolic acids affect the individual structure of gluten proteins: gliadins and glutenins, by understanding the underlying molecular interactions. Fourier transform infrared spectroscopy was used to determine changes in the secondary structure of the...