نوع مقاله : مقاله کامل علمی پژوهشی
نویسندگان
1 دانش آموخته کارشناسی ارشد مهندسی علوم و صنایع غذایی، دانشکده کشاورزی، دانشگاه آزاد اسلامی واحد اصفهان (خوراسگان)، اصفهان، ایران
2 گروه علوم و صنایع غذایی- دانشکده کشاورزی- دانشگاه ازاد اسلامی اصفهان (خوراسگان)-اصفهان -ایران- ۸۱۵۵۱۳۹۹۹۸
چکیده
کلیدواژهها
موضوعات
عنوان مقاله [English]
نویسندگان [English]
Background and objectives: traditional protein sources such as meat and dairy are facing environmental and resource efficiency challenges. Therefore, paying attention to alternative protein sources that can meet nutritional needs and at the same time be environmentally friendly has been found particularly important. Quinoa (Chenopodium quinoa Willd), a pseudocereal native to the Andean region, has attracted much attention due to its high nutritional value and numerous health benefits. The aim of this research was developing and optimizing a method for extracting quinoa protein regarding its functional properties in terms of emulsion activity and stability.
Materials and Methods: Quinoa flour was prepared from quinoa seeds and defatted with n-hexane, a suspension of flour and distilled water was prepared and pH was adjusted with sodium hydroxide solution according to the table suggested by the software used for the response surface method. The suspension was centrifuged and then the supernatant solution reached isoelectric pH with hydrochloric acid solution and the second centrifugation was performed, then the sediments were washed, neutralized and dried in a freeze dryer and the emulsion activity index and emulsion stability were measured. Protein extraction for evaluation of functional properties of quinoa was done using response surface method (RSM). The independent variables included isoelectric pH (4-5 minutes), centrifuge temperature (3-5 degrees Celsius) and alkaline pH (9-12). For data analysis design expert software and Box Benchen design with 6 replication at central point at probability of 5% was used. The t-student test was used to compare predicted and experimented conditions of optimal point.
Results: The results of analysis of variance to investigate the dependent variable of emulsion activity index showed that the quadratic model was significant (p < 0.0001). The interaction of temperature × isoelectric pH, alkaline pH × isoelectric pH, and alkaline pH × temperature were significant (p < 0.0001). Statistical analysis showed the dependent variable of emulsion stability shows that the quadratic model was significant (p < 0.0001). The interaction effect of temperature × isoelectric pH, alkaline pH × isoelectric pH, and alkaline pH × temperature were significant (p < 0.05). The results showed that the quadratic model could be used to predict the dependent variables. Isoelectric pH changes had a significant effect on emulsion activity index and its stability (p < 0.05). Temperature changes had a significant effect on emulsion activity index and its stability (p < 0.05). Changes in the alkaline pH had a significant effect on the emulsion activity index and its stability (p < 0.05). For numerical optimization, the values of the independent variables were within the defined range and the dependent variables were set to the maximum state.
Conclusion: The proposed treatment included alkaline pH of 9.00, isoelectric pH of 5 and temperature of 4.064 degrees Celsius. The experimented tests were performed in three repetitions. T-student test showed no significant difference between predicted and experimented conditions (p > 0.05). The results showed that quinoa protein could be used as an emulsifier in the food industry.
کلیدواژهها [English]