Determination of the effects of different pretreatment applications on some functional and bioactive properties of lentil

In this study, color values, total phenolic component amounts, antioxidant activities (free radical scavenging activity and iron ions chelating activity), soluble protein values of different extracts obtained from red and green lentil flours with different pretreatments. Water and oil holding capacity, emulsion forming capacity and stability, foam forming capacity and stability and antidiabetic activities were investigated. As a pre-treatment, boiling, baking, soaking, soaking in salt water and germination processes were applied. It has been observed that the pretreatments and lyophilization process have important effects on the determined properties. Significant amount of total phenolic component and antioxidant has passed from the lentil samples kept in water or alcohol to the liquid they contain. The pretreatments also affected the colors of the flours, water extracts and protein extracts. Total phenolic content values of green lentil liquid protein extracts were found to be higher than red lentils and the values varied between 47878 ± 267 and 12974 ± 431 μg gallic acid / g. Boiling and soaking in salt water significantly increased the total flavonoid content values. The free radical scavenging activity value of the green lentil control sample was found to be quite high compared to the red lentil, but boiling and soaking in water with a key decreased this value considerably. Although significant decreases were observed in total phenolic content and total flavonoid content values after lyophilization, significant increases were observed in some lentil protein extracts. Especially boiled red and green lentil protein extracts reached the highest free radical scavenging activity values among all extracts and these values were measured as 95.09 ± 5.86 and 247.01 ± 28.43 μmol trolox / g, respectively. Similarly, soluble protein values of boiled extracts were higher than other extracts. The pre-treated lentil flours had lower emulsion capacity compared to protein extracts. Boiling process significantly increased the emulsion stability of flours and protein extracts. After 60 minutes of incubation, 80.74 ± 0.47% in red lentil flour; 70.81 ± 1.15% in green lentil flour; Emulsion stability was determined as 87.86 ± 10.55% in red lentil protein extract and 81.52 ± 4.21% in green lentil protein extract. Similar foaming capacities were found in all lentil flour and protein extracts. However, while most of the lentil flours could not detect any foam after 30 and 60 minutes incubation, protein extracts showed that they had significant foam stability. While different pre-treatments applied reduce the protein stability of red lentil protein extracts; Water and liquid protein extracts produced from lentils did not show significant inhibition of alpha amylase, whereas red lentil solid protein extracts showed significant inhibition values. On the other hand, all extracts showed measurable alpha-glucosidase inhibition. It was observed that the alpha glucosidase inhibition value of the water extract and liquid protein extract produced after boiling pretreatment was higher. With this study, it was seen that the desired functional properties can be developed depending on the lentil type with different pre-treatments.