Use of Yeast Cells as Biocarrier in the Encapsulation Process

Yeast cells are carriers with great potential for encapsulation of both hydrophobic and hydrophilic compounds, due to protection from external environmental influences, controlled release, biocompatibility and biodegradability. The promising research results on the encapsulation of bioactive substances in the recent past promise a bright future in many fields such as agriculture, medicine and cosmetics, including functional food. The significant decrease in the stability of many bioactive compounds due to environmental conditions (heat, humidity, oxygen, etc.) has revealed the necessity of preserving the stability of these types of compounds by encapsulation process. After the recognition of yeast cells as suitable carriers for water-soluble flavor encapsulation, the possibilities of using various yeasts, especially Saccharomyces cerevisiae, in the encapsulation of various oils, vitamins, flavors and some phenolic compounds have been the subject of various scientific studies. The fact that the encapsulation process using yeast cells offers some advantages compared to other encapsulation methods has made the use of yeast cells in the encapsulation process very popular and there has been an increase in studies conducted in recent years. In this study, various scientific studies on the possibilities and effectiveness of the use of yeast cells in the encapsulation of various structures, especially various bioactive compounds, have been reviewed

Effects of Hybrid Drying on Kinetics, Energy Analysis and Bioactive Properties of Sour Black Mulberry (Morus nigra L.)

Abstract Due to the short harvest season and their sensitivity to storage, the preservation of fresh mulberry fruits is a very important process. Drying is a method used to preserve mulberry fruits in the long term. In this study, response surface methodology (RSM) was applied for the optimization of hybrid drying conditions of two different sour black mulberries. The linear and interaction effects of independent parameters such as temperature (50, 60 and 70°C) and microwave power (100, 200 and 300 W) variables were determined on mulberries. Bioactive properties and energy aspects were monitored as influenced by drying conditions. According to the results increase in microwave power provided a significant decrement in the specific energy consumption (SEC) and the total anthocyanin content (TAC), while increase in the energy efficiency (ηen) and total phenolic content (TPC) for both genotypes. In all cases, statistical values showed that all drying curves of black mulberry were best described by the Logistic model. Multiple response optimization was carried out for studied parameters and it was concluded that maximum antiradical activity (ARA), TPC, TAC, ηen and minimum drying time (DT) and SEC values would be at 300 W-50 ºC (desirability=0.842) and 300 W-66.5 ºC (desirability=0.744), for Morus nigra 1 (MN1) and Morus nigra 2 (MN2), respectively. According to the finding, the greatest TPC, ARA, TAC, DT, SEC and ηen were determined as 20.10 mg GAE/g, 86.00%, 456 mg/kg, 330 min, 18.59 kWh/kg and 9.04% for MN1, and 18.08 mg GAE/g, 83.92%, 835.81 mg/kg, 330 min, 16.16 kWh/kg and 10.40 % for MN2, respectively

Fabrication of gallic acid loaded yeast (Saccharomyces cerevisiae) microcapsules: Effect of plasmolysis treatment and solvent type on bioactivity and release kinetics

In this study, gallic acid (GA) which is one of the most popular phenolics was encapsulated using yeast cell (S. cerevisiae) and effects of plasmolysis treatment and solvent type of encapsulation media (H2O or EtOH:H2O) on encapsulation performance, bioactive properties, morphological-conformational characteristics and release behavior at simulated gastric and intestine medium (pH 1.2 and 6.8) were investigated. Encapsulation efficiency (EE) was determined to be significantly higher in nonplasmolysed yeast cells treated with H2O (NPYC-H2O). GA concentration of microcapsules ranged between 6.48 and 94.76 mg GAE/g sample and the microcapsules showed antioxidant and antiradical activity. It was revealed that the solvent type of encapsulation media showed significant effect on the EE and studied bioactive parameters. GA released from yeast cells efficiently in both pH 1.2 and 6.8, more than 80% after 2 h of release and the releasing behavior was explained by Korsmeyer-Peppas kinetic model by high fitting performance. It was concluded that GA could be encapsulated by nonplasmolysed yeast cell in aqueous media effectively