Impact of high-intensity ultrasound on the physicochemical and functional properties of a protein isolate from passion fruit (Passiflora edulis) seeds

Abstract A protein isolate from passion fruit seeds (PFSPI) obtained by alkaline extraction and isoelectric precipitation was treated with sonication for 15 and 30 min at 40 kHz to evaluate its impact on the physicochemical and functional properties. The PFSPI had a purity of 96.21% protein, with albumins being the main fraction (75.66%). Ultrasound increased the bulk density (ρ) of PFSPI by 13.3% and the formation a more porous structure by a greater separation between particles. Protein solubility of PFSPI in the range of pH 2–12 sonicated for 15 and 30 min, increased on average 5.21 and 9.86%, respectively, in comparison with the control. PFSPI foaming properties were influenced by pH and sonication time, achieving up to 577%, while the minimum gelling concentration was reduced from 4 to 2% at pH 7. Therefore, sonication treatment improved some functional properties of PFSPI for its potential use as a food ingredient.

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Functional properties of protein isolates from camelina (Camelina sativa (L.) Crantz) and flixweed (sophia, Descurainis sophia L.) seed meals

Food Production, Processing and Nutrition ◽

10.1186/s43014-021-00076-8 ◽

2021 ◽

Vol 3 (1) ◽

Author(s):

Na Thi Ty Ngo ◽

Fereidoon Shahidi

Keyword(s):

Functional Properties ◽

Protein Extraction ◽

Protein Profile ◽

Protein Solubility ◽

Protein Isolate ◽

Absorption Capacity ◽

Foaming Properties ◽

Oil Absorption ◽

Protein Isolates ◽

Water Holding

AbstractCamelina and flixweed (sophia) seed protein isolates were prepared using both the conventional extraction and ultrasonic-assisted extraction methods at 40 kHz for 20 min, and their functional properties investigated. SDS-PAGE showed that both ultrasound-assisted and conventional extractions resulted in a similar protein profile of the extract. The application of ultrasound significantly improved protein extraction/content and functional properties (water holding capacity, oil absorption capacity, emulsifying foaming properties, and protein solubility) of camelina protein isolate and sophia protein isolate. The water-holding and oil absorption capacities of sophia protein isolate were markedly higher than those of camelina protein isolate. These results suggest that camelina protein isolate and sophia protein isolate may serve as natural functional ingredients in the food industry. Graphical Abstract

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Functional Properties of the Protein Isolate and Major Fractions of Pine Nut Proteins Prepared from the Changbai Mountain in China

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.881-883.766 ◽

2014 ◽

Vol 881-883 ◽

pp. 766-775 ◽

Cited By ~ 1

Author(s):

Dan Wu ◽

Wei Hong Min ◽

Jing Sheng Liu ◽

Li Fang ◽

Hong Mei Li ◽

...

Keyword(s):

Amino Acids ◽

Functional Properties ◽

Protein Solubility ◽

Essential Amino Acids ◽

Protein Isolate ◽

Absorption Capacity ◽

Changbai Mountain ◽

Major Protein ◽

Pine Nut ◽

A Value

The functional properties of protein isolate and major protein fractions prepared from Changbai Mountain pine nuts were investigated. Albumin, globulin, glutelin, and protein isolates were obtained after the Osborne method and alkaline dissolution and acid precipitation, and protein contents of the fractions are 48.02%, 81.93%, 83.02%, and 89.69%, respectively. For the sulfhydryl contents, albumin is the highest, and glutelin is the lowest. In a disulphide bond, the protein isolate content is the highest with a value of 28.74 μmol/g, and the glutelin content is the lowest with the value of 13.46 μmol/g. For the four kinds of proteins, the essential amino acids in percentage of total amino acids are 31.13%, 34.22%, 30.30%, and 34.54%, respectively. The pH dependent protein solubility profile reveals that the minimum solubility is at pH 5.0, which corresponds to the isoelectric point. Protein isolate has the minimum water absorption capacity with a value of 0.59 ml/g. On the other hand, albumin has the minimum oil absorption capacity with a value of 2.11 ml/g. The emulsifying activity and stability and the foaming activity and stability increased with increasing concentration of four kinds of proteins. SDS-PAGE results showed that these four kinds of proteins have different molecules.

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