Physicochemical and functional properties of lentil protein isolates prepared by different drying methods

• Published in: Food chemistry Vol. 129; no. 4; pp. 1513 - 1522
• Main Authors: Joshi, M., Adhikari, B., Aldred, P., Panozzo, J.F., Kasapis, S.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 15-12-2011; Elsevier
• Subjects: Biological and medical sciences; Drying; Food engineering; Food industries; Fundamental and applied biological sciences. Psychology; Gelation; General aspects; Lentil protein isolate; SDS–PAGE; Solubility; Texture; Lentil protein isolate; SDS–PAGE; Texture; Gelation; Solubility; Drying; Lentil; SDS-PAGE; Protein isolate; Method; Physicochemical properties
• ISSN: 0308-8146; 1873-7072
• DOI: 10.1016/j.foodchem.2011.05.131

► Differently dried lentil protein powders had similar chemical but different physical properties. ► Spray-dried lentil protein powder had higher solubility in water. ► All the lentil protein powders were able to form viscoelastic gels. ► Gelation capacity of spray and freeze-dried powders was superior to that of vacuum-dried powder. ► The spray dried powders had low water absorption capacity than the other two powders.
Lentil protein isolate (LPI) extract was converted into powder by freeze drying, spray drying and vacuum drying. Differences in particle size distribution, protein subunit composition and colour and surface morphology were observed amongst the three drying methods. Spray and freeze-dried LPI powders exhibited higher solubility (81% and 78%, respectively) compared to vacuum dried powders (50%). The spray dried powders showed a low water absorption capacity (0.43±0.02g/g) compared to freeze (0.48±0.02g/g) and vacuum-dried (0.47±0.01g/g) LPI powders. Spray and freeze-dried powders displayed better gelation ability and higher gel strength, compared to vacuum-dried powder. Both spray and freeze-dried gels showed typical viscoelastic gel characteristics, with G′ dominating over G″ and very low loss tangent. The holding time required for gelation of vacuum dried powder at 90°C was significantly longer, compared to spray and freeze dried powders. Hence, drying methods used for preparation of lentil protein isolate powders can affect physicochemical and associated functional properties.