جستجوی مقالات مرتبط با کلیدواژه « انجماد-انجمادزدایی » در نشریات گروه « کشاورزی »

The purpose of this research was to investigate different methods of protein extraction and compare and choose the best method for the functional properties of protein from spirulina microalgae. Microalgae are one of the most important sources of protein. Proteins play a very important role in human health and are widely used in various industries. . In this research, different methods (freezing-thawing, homogenization, ultrasonic waves and soaking in ethanol and water solutions) were investigated to extract and isolate protein from spirulina microalgae. The functional properties of extracted proteins (water retention capacity, foam production and stability, and emulsifying capacity of the samples) were investigated. According to the results, the extraction method had an effect on the functional properties of the protein (p<0/05). According to the obtained results, the use of mechanical methods for protein extraction resulted in better preservation of functional properties. The functional properties of protein (Water holding capacity, emulsion stability index, foam stability, foam ability, samples extracted with the help of homogenization, ultrasound, freezing and thawing methods were more than other treatments (p<0.05). The index of emulsification capacity and water holding capacity in samples extracted with 4 freeze-thaw cycles was higher than all treatments. The highest level of emulsion stability and foam production was in the samples extracted with ultrasonic waves. According to the results, the use of ultrasonic waves and freeze-thawing cycle is suggested for protein extraction from spirulina microalgae.

Spirulina is blue-green microalgae as an excellent source of protein and natural food colors such as phycobiliproteins, chlorophylls. So, extraction of these bioactive compounds is important. In this study, the mechanical treatments (freeze-defreeze, homogenization, ultrasonic), and chemical treatment (soaking in ethanol and water) were performed and extraction and separation of protein and chlorophyll from Spirulina microalgae were done in the separate and continuous way of Spirulina mass. The yield of extracted chlorophyll and protein, the absorption spectrum of the samples (200-800 nm), and the amino acid profile of the extracted proteins by the selected treatments were tested. According to the results, the extraction yield of chlorophyll in a continuous way was higher than in a separate method, and extraction with ethanol in both separate and continuous ways was a suitable solvent and showed higher efficiency (P<0.05). The freeze-defreeze cycle was also effective in chlorophyll extraction. The protein extraction, homogenization, and ultrasound treatments were acted more appropriately to mechanically break down cell walls and increased extraction efficiency (P<0.05). In the same conditions, the continuous way of extracting chlorophyll and protein showed higher efficiency than the separate way, and homogenization and ultrasound are recommended and ethanol was suitable solvent in chlorophyll extraction and the freeze-defreeze treatment was appropriate at split the cell wall.