Mathematical modeling of weight loss and crust temperature of toast bread containing guar gum during baking process

Encapsulation of felty germander (Teucrium polium L.) extract using the freeze-drying method

Extracts with antimicrobial and antioxidant properties are limited in their application in food products due to their inability to withstand harsh environmental conditions, such as high temperatures and oxygen exposure. Therefore, the present study investigated the nanoencapsulation of Teucrium polium L. extract using the freeze-drying method to facilitate its application and protection against environmental factors. In this regard, an emulsion containing Teucrium polium L. extract at concentrations of 10%, 20%, and 30% and a mixture of maltodextrin/Persian gum in three ratios of 1:2, 1:1, and 2:1 as the coating wall were produced and then dried in a freeze dryer. In the following, the properties of emulsions and produced nanocapsules were studied. According to the results, emulsions with high amounts of Persian gum showed more stability, zeta potential, and viscosity. However, their particle size and polydisparity index were lower than those of other emulsions. As the extract concentration increased, there was a decrease in stability, zeta potential, and viscosity, accompanied by an increase in particle size and polydispersity index. Concurrently, elevated concentrations of maltodextrin, Persian gum, and extract resulted in higher humidity, density, encapsulation efficiency, and antioxidant activity of the capsules. The most optimal properties of emulsions and nanocapsules were achieved at the 10% concentration of Teucrium polium L. extract and the 1:1 ratio of maltodextrin/Persian gum mixture as the wall material. It is noteworthy that the release rate of phenolic compounds reached its maximum value (88%) after 60 days.

The effect of propolis extract as a valuable natural additive on the quality characteristics of toast bread

This study aimed to evaluate the effect of ethanolic propolis extract (EPE) as a natural antimicrobial and antioxidant agent on the physicochemical, microbial, and sensory characteristics of toast bread, as well as phenol content and antioxidant activity. In this regard, 0.1, 0.3, and 0.5% of EPE were used in the bread doughs and the quality characteristics of the breads were assessed. The bread with 0.5% EPE showed the highest phenolic content (24.02 mgGAE/g.d.m) and antioxidant activity (59.03%). These amounts were 12.96 mgGAE/g and 16.45% higher than those of the control (without EPE), respectively (p < .05). The hardness, fracturability, and chewiness of the bread samples were influenced by the levels of EPE on the third and fifth days of storage. EPE decreased the L* and a* of bread samples, but an increasing trend was observed in the b*, chroma, and browning index by elevating the levels of propolis. Propolis extract showed an inhibitory effect on mold growth in samples. The bread with 0.5% of EPE had the lowest mold count after 5 days of storage which was not significant compared to the first day. There was no significant difference in sensory evaluation between the overall acceptance of bread samples. Therefore, EPE has the potential to be used as a natural additive with antimicrobial and antioxidant characteristics in toast bread.

Application of guar (Cyamopsis tetragonoloba L.) gum in food technologies: A review of properties and mechanisms of action

With the world continuing to push toward modernization and the consumption of processed foods growing at an exponential rate, the demand for texturizing agents and natural additives has also risen as a result. It has become increasingly common to use thickening agents in food products to modify their rheological and textural properties and enhance their quality characteristics. They can be divided into (1) animal derived (chitosan and isinglass), (2) fermentation produced (xanthan and curdlan), (3) plant fragments (pectin and cellulose), (4) seaweed extracts (agar and alginate), and (5) seed flours (guar gum and locust bean gum). The primary functions of these materials are to improve moisture binding capacity, modify structural properties, and alter flow behavior. In addition, some have another responsibility in the food sector, such as the main ingredient in the delivery systems (encapsulation) and nanocomposites. A galactomannan polysaccharide extracted from guar beans (Cyamopsis tetragonolobus), known as guar gum (GG), is one of them, which has a wide range of utilities and possesses popularity among scientists and consumers. In the world of modernization, GG has found its way into numerous industries for use in food, cosmetics, pharmaceuticals, textiles, and explosives. Due to its ability to form hydrogen bonds with water molecules, it imparts significant thickening, gelling, and binding properties to the solution as well as increases its viscosity. Therefore, this study is aimed to investigate the characteristics, mechanisms, and applications of GG in different food technologies.