scholarly journals Functional properties of proteins isolated from industrially produced sunflower meal

2014 ◽  
Vol 3 (2) ◽  
Author(s):  
Petia Ivanova ◽  
Vesela Ivanova Chalova ◽  
Lidia Koleva

Protein isolate 1 (PI1) and protein isolate 2 (PI2) were prepared from industrially produced sunflower meal by using isoelectric and ethanol precipitation respectively. The water absorption capacity of PI1 was 6 times higher than that of PI2 and was significantly reduced by the presence of 0.03 M and 0.25 M NaCl. Oil absorption capacity of both protein isolates was not influenced by NaCl supplementation. Foam capacity of PI1 and PI2 was pH-dependent. While the foam capacity of both isolates was improved by either 0.03 M or 0.25 M NaCl, the foam stability was negatively influenced by the addition of NaCl at all pH values with except for pH 4. Emulsifying activity of PI1 and PI2 was lowest at pH 4. The emulsions exhibited relatively high stability (> 90%) under all studied conditions. Knowledge of the influence of pH and boundary concentrations of NaCl on the functionality of sunflower meal protein isolates could be beneficial for their future potential application in food industry.

Foods ◽  
2021 ◽  
Vol 10 (10) ◽  
pp. 2297
Author(s):  
Alvaro Villanueva-Lazo ◽  
Sergio Montserrat-de la Paz ◽  
Noelia Maria Rodriguez-Martin ◽  
Francisco Millan ◽  
Cecilio Carrera ◽  
...  

Twelve high-quality chia protein hydrolysates (CPHs) were produced from chia protein isolate (CPI) in a pilot plant of vegetable proteins. To obtain functional hydrolysate, four CPHs were hydrolyzed by the action of Alcalase, an endoprotease, and the other eight CPHs were hydrolyzed by the action of Flavourzyme, an exoprotease. Alcalase-obtained CPHs showed significant antihypertensive properties particularly, the CPH obtained after 15 min of hydrolysis with Alcalase (CPH15A), which showed a 36.2% hydrolysis degree. In addition, CPH15A increased the antioxidant capacity compared to CPI. The CPH15A physicochemical composition was characterized and compared to chia defatted flour (CDF) and CPI, and its techno-functional properties were determined by in vitro experiments through the analysis of its oil absorption capacity, as well as the capacity and stability of foaming and emulsifying, resulting in an emulsifier and stabilizer better than the intact protein. Therefore, the present study revealed that CPH15A has potent antihypertensive and antioxidant properties and can constitute an effective alternative to other plant protein ingredients sources that are being used in the food industry.


2021 ◽  
Vol 3 (1) ◽  
Author(s):  
Na Thi Ty Ngo ◽  
Fereidoon Shahidi

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


Foods ◽  
2020 ◽  
Vol 9 (6) ◽  
pp. 703
Author(s):  
Hristo Kalaydzhiev ◽  
Radoslav Georgiev ◽  
Petya Ivanova ◽  
Magdalena Stoyanova ◽  
Cristina L. M. Silva ◽  
...  

The solubility of plant protein isolates is a key determinant of their potential application. Two protein isolates (PI) from ethanol-treated industrial rapeseed meal, PI10.5–2.5 and PI2.5–8.5, were prepared by sequential isoelectric precipitation of alkali-extracted proteins (pH 12) starting from pH 10.5 to 2.5 or from pH 2.5 to 8.5, respectively. Biochemical analyses revealed that PI2.5–8.5 contained a higher amount of crude protein (72.84%) than PI10.5–2.5 (68.67%). In the same protein isolate, the level of total phenols (0.71%) was almost two-fold higher than that in PI10.5–2.5 (0.42%). No glucosinolates were established in both protein isolates. SDS-PAGE analysis demonstrated that PI10.5–2.5 contained 10 to 15 kDa protein fractions in a relatively higher amount, while PI2.5–8.5 was enriched in 18 to 29 kDa protein fractions. PI10.5–2.5 exhibited high solubility, varying from 41.74% at pH 4.5 to 65.13% at pH 6.5, while PI2.5–8.5 was almost two-fold less soluble under the same conditions. Up to pH 5.5, the addition of NaCl at 0.03 and 0.25 M diminished the solubility of PI2.5–8.5, while the solubility of PI10.5–2.5 was increased. The supplementation of PI10.5–2.5 with 0.25 M NaCl enhanced the protein solubility to 56.11% at pH 4.5 and 94.26% at pH 6.5. The addition of 0.03 M NaCl also increased the solubility of this protein isolate but to a lower extent. Overall, the approach for sequential precipitation of proteins influenced the biochemical characteristics, protein fractional profile and solubility of prepared protein isolates.


2004 ◽  
Vol 10 (4) ◽  
pp. 263-267 ◽  
Author(s):  
P. S. Bora ◽  
D. Ribeiro

Three protein isolates from de-fatted macadamia nut kernel flour were prepared by extraction at acidic (pH2.0), neutral (pH7.2 with 0.2M phosphate buffer containing 0.5MNaCl) and alkaline (pH12.0) conditions. Extraction at pH2.0 solubilised nearly 52.0% of the proteins present in defatted macadamia flour, while extraction with buffer (pH7.2) and alkaline pH (12.0) solubilised about 83.0% of proteins. The yield of isoelectrically precipitated protein from acidic extract (pH2.0, isolate A) was about 65.2% and from neutral (isolate B) and alkaline extracts (isolate C) was slightly over 83.0% which accounted for 33.7, 69.1 and 69.4% of the proteins present in defatted flour. The protein content of the isolates was 80.1, 92.1 and 92.0% in A, B and C isolates respectively. The functional properties of these isolates were significantly different. Isolate A presented better solubility at pH below isoelectric pH, isolate C at pH above isoelectric pH and isolate B intermediate solubility at the pH range studied. Isolate B showed best water and oil absorption capacities followed by isolate C and least by isolate A. For each isolate, the emulsifying properties were also significantly different at different pH values.


1979 ◽  
Vol 6 (1) ◽  
pp. 1-6 ◽  
Author(s):  
Esam M. Ahmed ◽  
Ronald H. Schmidt

Abstract Proteins were extracted from defatted Florunner peanuts and Cobb soybeans and dried using different methods. Freshly prepared peanut protein isolates contained 73.9 to 81.3% protein and 1.4 to 4.3% fat. The corresponding values for soybeans were 54.7 to 61.6% and 2.7 to 4.5%. Spray dried peanut protein isolate contained 69.1% protein after 36 months storage and exhibited less solubility than those stored for 24 months or freshly prepared. Freeze dried soybean isolate contained more soluble protein man the freeze dried peanut protein isolate. The reverse was true for the spray dried peanut and soybean isolates. Protein solubility, emulsifying capacity, foaming capacity and foam stability of peanut and soybean protein isolates were higher for the spray dried and freeze dried than the drum dried preparations. Heat treatment of peanuts (107°C for 20 min.) did not influence protein solubility or emulsifying capacity but decreased foaming capacity and foam stability. Storage of peanut isolates resulted in a loss of emulsifying capacity, especially for the freeze dried peanut preparation.


2020 ◽  
Vol 12 (1) ◽  
pp. 77-83 ◽  
Author(s):  
Muhammad Elsayed Elsorady

Flaxseed protein isolate (FPI) and sesame protein isolate (SPI) were extracted from flaxseed and sesame cake as by-products, and their functional properties (water holding and fat absorption capacities, bulk density, least gelling concentration, solubility, and emulsifying properties) were determined. Bulk density of the SPI (0.162 g/ml) was lower than that of the FPI (0.175 g/ml). The water absorption capacity of the FPI (305.66%) was higher than that of the SPI (288.93%). The oil absorption capacity and least gelling capacity of the FPI and SPI were 127.48, 3.6, 134.39, and 5%, respectively. The least solubility occurred at pH 4.0 and it was 24.54, 9.56% for FPI and SPI, respectively. Levels of pH and salt concentrations were used as dependent variables for the characterization of emulsifying capacity, activity, and emulsion stability, as well as foaming capacity and foam stability. The addition of NaCl at concentrations up to 1.0 M improved these characteristics. The SPI and FPI had a minimum emulsion capacity (74.54 and 100.20 ml oil/g protein, respectively) and a minimum foam capacity (14.25 and 17.35 %, respectively) at pH 4. The FPI and SPI were found to be highly soluble at acidic and alkaline pH and their emulsifying and foaming properties were high. Moreover, their bulk density, water absorption, and fat absorption capacities and least gelling capacity properties were good. Therefore, the FPI and SPI can be used in food formulation systems.


Author(s):  
Katarina Katić ◽  
Katarina Banjanac ◽  
Milica Simović ◽  
Marija Ćorović ◽  
Ana Milivojević ◽  
...  

2014 ◽  
Vol 3 (6) ◽  
pp. 168
Author(s):  
Abbas Kisambira ◽  
John H. Muyonga ◽  
Yusuf B. Byaruhanga ◽  
Phinehas Tukamuhabwa ◽  
Silver Tumwegamire ◽  
...  

<p>This study sought to determine the physicochemical and functional properties of yam bean (<em>Pachyrhizus erosus</em>) seed proteins. <em>Pachyrhizus erosus</em> seeds from two accessions (UYB 06 and UYB 07) were milled into flours and then defatted. A portion of the defatted flour was used for production of protein isolates and protein fractions. The physicochemical and functional properties, <em>in vitro</em> digestibility and electrophoretic pattern of the flour and protein isolate were determined. The results showed that albumins (53.3%) were the dominant protein fraction followed by globulins (18.7%), glutelins (8.8%) and prolamins (2.7%). Regarding functional properties, the <em>Pachyrhizus erosus</em> seed protein isolates exhibited 8% of least gelation concentration, water absorption capacity of 3.0 g g<sup>-1</sup>, oil absorption capacity of 0.8 g g<sup>-1</sup>, protein solubility of 81.0%, foaming capacity of 37.1%, foam stability of 73.8%, emulsion activity of 13.8% and emulsion stability of 9.2%. <em>In vitro</em> protein digestibility of the raw and cooked beans was 87.6% and 84.3%, respectively. The electrophoretic pattern of<em> Pachyrhizus erosus</em> protein showed major bands corresponding to molecular weight 13.3, 15, 29.8, 54.4 and above 84.7 kDa. The results, suggest that <em>Pachyrhizus erosus </em>seed protein has potential for use in both food and non-food applications such as films and coating.</p>


2014 ◽  
Vol 881-883 ◽  
pp. 766-775 ◽  
Author(s):  
Dan Wu ◽  
Wei Hong Min ◽  
Jing Sheng Liu ◽  
Li Fang ◽  
Hong Mei Li ◽  
...  

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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