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1.
Preparation and characterisation of protein hydrolysates from Indian defatted rice bran meal 总被引:1,自引:0,他引:1
Rice bran meal is a very good source of protein along with other micronutrients. Rice bran meal has been utilized to produce protein isolates and respective protein hydrolysates for potential application in various food products. De-oiled rice bran meal, available from Indian rice bran oil extraction plants, was initially screened by passing through an 80-mesh sieve (yield about 70%). A fraction (yield-30%) rich in fibre and silica was initially discarded from the meal. The protein content of the through fraction increased from 20.8% to 24.1% whereas silica content reduced from 3.1% to 0.4%. Rice bran protein isolate (RPI) was prepared by alkaline extraction followed by acidic precipitation at isoelectric point. This protein isolate was hydrolysed by papain at pH 8.0 and at 37 degrees C for 10, 20, 30, 45 and 60 minutes. The peptides produced by partial hydrolysis had been evaluated by determining protein solubility, emulsion activity index (EAI), emulsion stability index (ESI), foam capacity and foam stability (FS). All protein hydrolysates showed better functional properties than the original protein isolate. These improved functional properties of rice bran protein hydrolysates would make it useful for various application especially in food, pharmaceutical and related industries. 相似文献
2.
Enzymatic modification of soy protein concentrates by fungal and bacterial proteases 总被引:9,自引:0,他引:9
L. S. Bernardi Don A. M. R. Pilosof G. B. Bartholomai 《Journal of the American Oil Chemists' Society》1991,68(2):102-105
Solubility, foaming capacity and foam stability of denatured soy protein concentrate obtained from toasted flour were improved
by proteolysis with fungal or bacterial proteases. Emulsifying capacity was unchanged, but emulsion stability decreased; bacterial
protease highly improved oil absorption. Also, the bacterial protease was able to solubilize more protein and gave products
which foamed more than those obtained with the fungal enzyme. However, the stabilizing properties of the bacterial modified
soy protein concentrate at the air/water or oil/water interface were inferior. By limited hydrolysis up to degree of hydrolysis
10% most functional properties were improved without greatly reducing emulsion stability and water absorption. 相似文献
3.
Enzymatic hydrolysis of extruded-expelled soy flour and resulting functional properties 总被引:1,自引:0,他引:1
B. P. Lamsal C. Reitmeier P. A. Murphy L. A. Johnson 《Journal of the American Oil Chemists' Society》2006,83(8):731-737
Limited hydrolysis (4% degree of hydrolysis) of extruded-expelled soy flour protein (protein dispersibility index=21) that
was poor in solubility and other functional properties was evaluated at pilot-plant scale (5 kg of flour) with two endopeptidases
and one exopeptidase. Some hydrolysates were merely spray-dried whereas others were jet-cooked at 104°C for 19 s before spray-drying.
Solubility, emulsification capacity and stability, foaming capacity and stability, apparent viscosity, and sensory attributes
were then characterized. The type of protease used and hydrothermal cooking affected functional and sensory properties. Protein
solubility modestly increased with hydrolysis and jet cooking, but emulsification capacity decreased on hydrolysis and was
not restored with hydrothermal cooking. Emulsion stability improved in the endopeptidase hydrolysates, but not in the exopeptidase
hydrolysates. The foaming capacities of the hydrolysates for both types of enzymes were better than for the unhydrolyzed control.
Highly stable foams were obtained after hydrolyzing with exopeptidase and hydrothermal cooking. Ten percent protein hydrolysate
dispersions showed large losses in consistency coefficient apparent viscosity, which increased significantly with hydrothermal
cooking only for the unhydrolyzed control. Difference-from-control sensory evaluation indicated that both jet-cooked and non-jet-cooked
enzyme hydrolysates were different from unhydrolyzed controls. 相似文献
4.
Barać M Cabrilo S Pešić M Stanojević S Pavlićević M Maćej O Ristić N 《International journal of molecular sciences》2011,12(12):8372-8387
In this paper, the effects of limited hydrolysis on functional properties, as well as on protein composition of laboratory-prepared pea protein isolates, were investigated. Pea protein isolates were hydrolyzed for either 15, 30 and 60 min with recombined chymosin (Maxiren). The effect of enzymatic action on solubility, emulsifying and foaming properties at different pH values (3.0; 5.0; 7.0 and 8.0) was monitored. Chymosin can be a very useful agent for improvement of functional properties of isolates. Action of this enzyme caused a low degree of hydrolysis (3.9-4.7%), but improved significantly functional properties of pea protein isolates (PPI), especially at lower pH values (3.0-5.0). At these pH values all hydrolysates had better solubility, emulsifying activity and foaming stability, while longer-treated samples (60 min) formed more stable emulsions at higher pH values (7.0, 8.0) than initial isolates. Also, regardless of pH value, all hydrolysates showed improved foaming ability. A moderate positive correlation between solubility and emulsifying activity index (EAI) (0.74) and negative correlation between solubility and foam stability (-0.60) as well as between foam stability (FS) and EAI (-0.77) were observed. Detected enhancement in functional properties was a result of partial hydrolysis of insoluble protein complexes. 相似文献
5.
Christophe Malabat Ra I S nchez-Vioque Claude Rabiller Jacques Gu guen 《Journal of the American Oil Chemists' Society》2001,78(3):235-242
The 2S and 12S proteins of rapeseed were isolated and subsequently hydrolyzed by pepsin or a combination of pepsin plus trypsin.
The resulting hydrolysates had a 15% degree of hydrolysis and were purified by gel filtration chromatography in order to obtain
homogeneous peptide fractions. Three major fractions, having an average peptide chain length of 7.5–11 amino acids, were recovered.
Purified peptide fractions were acylated with butyric anhydride and sulfamidated with p-toluenesulfonyl chloride. The degree of modification was always higher than 90%. Emulsifying and foaming properties of native
and chemically modified peptides were studied and compared to those of sodium dodecyl sulfate (SDS) as standard. A peptide
fraction from the 15% hydrolysis of the 12S protein exhibited the best foaming properties. After sulfamidation, this peptide
fraction showed a foam formation similar to that of SDS. Whereas the attachment of toluene groups generally improved the surface
properties, the incorporation of an aliphatic chain of four atoms of carbon was detrimental in most of the cases. On the other
hand, none of the native or hydrophobized peptide fractions was able to form a stable emulsion. 相似文献
6.
The functional characteristics which include protein solubility at different pH, emulsifying and foaming properties, degree of hydrolysis, molecular weight distribution, antioxidant and ACE inhibitory activity of sesame protein hydrolysates prepared with pepsin, papain and alcalase enzymes were evaluated. The rate of degree of hydrolysis was found to reach maximum (25–30%) within the first time fragment i.e 10 min but 80% of hydrolysis was obtained in 120 min with alcalase. SDS-PAGE of hydrolysates with papain, pepsin and alcalase evinced bands of low molecular weight protein of 14.3 kDa and even lower for alcalase treatment of 120 min. Hydrolysates so formed were of improved functional properties as evident from emulsifying and foaming property. Hydrolysis with different proteases enhanced the protein solubility significantly at pH 7.0. Antioxidative assay revealed radical scavenging activity of the hydrolysates with papain hydrolysates showing maximum antioxidative efficacy. The ultra-filtered peptide fractions which showed comparable ACE inhibitory activity were sequenced by MALDI-TOF and matched to that of previously identified ACE inhibitory peptides. The results corroborate the ACE inhibitory effect of the peptides. Hence, these highly bioactive protein hydrolysates produced from waste sesame meals can be successfully employed in various functional food formulations. 相似文献
7.
Physicochemical properties of pronase-treated rice glutelin 总被引:11,自引:0,他引:11
Rice glutelin protein was extracted from defatted medium-grain rice by alkali extraction followed by acid precipitation. Extracted
glutelin was hydrolyzed with Pronase E, a bacterial protease, and the functional properties of hydrolysates were evaluated.
Nitrogen solubility of pronase-treated glutelin protein increased from pH 2 to pH 12. Similarly, foaming and emulsion properties
of hydrolyzed protein also showed improved characteristics. The emulsion activity, expressed as the turbidity of diluted emulsions,
was significantly greater (P≤0.05) for hydrolyzed samples. However, turbidity for all samples decreased with increased homogenization time, indicating
a decrease in the volume of dispersed oil. There were significant changes in apparent viscosity as a function of shear rate,
with viscosity decreasing with increasing shear rate. The viscosity of dispersions of all hydrolyzed samples was significantly
lower than that of the native sample at all shear rates tested. Enzymatic hydrolysis of rice endosperm storage glutelin proteins
appeared to improve the functional characteristics of the hydrolyzed proteins. 相似文献
8.
Analysis of products, mechanisms of reaction, and some functional properties of soy protein hydrolysates 总被引:11,自引:0,他引:11
Sara E. Molina Ortiz Mara Cristina An 《Journal of the American Oil Chemists' Society》2000,77(12):1293-1301
Soybean protein isolates were hydrolyzed with papain, bromelain, cucurbita, hieronymin, and pomiferin. The highest hydrolysis
rate for cucurbita and the lowest for papain was detected at 720 min. Gel filtration, reversed-phase liquid chromatography,
and electrophoresis showed that the action of each protease was different. Pomiferin acted on the native structure of β-conglycinin
and glycinin, generating a large number of small hydrolysis products with hydrophilic and hydrophobic characteristics. The
hydrolysates obtained with cucurbita showed residual structures that were almost intact and very similar to the substrate
and contained a low number of small peptides. The hydrolyzates obtained with papain, bromelain, and hieronymin had hydrolysis
products with structures similar to the partially hydrolyzed native isolate. The molecular masses of these products were similar
to or lower than the controls. Polypeptides of low molecular mass were also detected. The prevalence of one-by-one and zipper
mechanisms was suggested for cucurbita and pomiferin, respectively. For the other proteases both mechanisms were likely to
coexist. The solubility of hydrolysates and their ability to form and stabilize foams correlated well with the structural
properties and with the suggested mechanisms of hydrolysis. The best properties were presented by the hydrolysates prepared
with cucurbita. Foaming ability for pomiferin hydrolysates was as high as that for unhydrolyzed soy isolate, but the foams
were extremely unstable. 相似文献
9.
In Vitro Acetylcholinesterase-Inhibitory Properties of Enzymatic Hemp Seed Protein Hydrolysates 下载免费PDF全文
The aim of this work was to characterize the structural and functional properties of hemp seed protein‐derived acetylcholinesterase (AChE)‐inhibitory enzymatic hydrolysates. Hemp seed protein isolate hydrolysis was performed using six different proteases (pepsin, papain, thermoase, flavourzyme, alcalase and pepsin + pancreatin) at different concentrations (1–4 %). The degree of hydrolysis was directly related to the amount of protease used but had no relationship with AChE‐inhibitory activity. Amino acid composition results showed that the hemp seed protein hydrolysates (HPHs) had high levels of negatively charged amino acids (39.62–40.18 %) as well as arginine. The 1 % pepsin HPH was the most active AChE inhibitor with ~6 µg/mL IC50 value when compared to 8–11.6 µg/mL for the other HPHs. Mass spectrometry analysis showed that most of the peptides in all the hydrolysates were less than 1000 Da in size. However, the pepsin HPHs contained larger‐sized peptides (244–1009 Da) than the papain HPHs (246–758 Da), which in turn was larger than the alcalase HPH (246–607 Da). The higher AChE‐inhibitory effects of the pepsin HPHs may be due to increased synergistic effects from a wider peptide size range when compared to the papain and alcalase HPHs that had narrower ranges. The narrow peptide size range in the alcalase HPH confirms the higher efficiency of this protease in releasing small‐sized peptides from food proteins. 相似文献
10.
Ljiljana Popović Draginja Peričin Žužana Vaštag Senka Popović Vera Krimer Aleksandra Torbica 《Journal of the American Oil Chemists' Society》2013,90(8):1157-1165
Cucurbitin extracted from pumpkin (Cucurbita pepo) oil cake was enzymatically hydrolysed with three different enzymes viz. alcalase, flavourzyme and pepsin. Antioxidative and functional properties of cucurbitin hydrolysates with different degrees of hydrolysis (DH) were investigated. The antioxidant activity of the hydrolysates was strongly dependent on the enzyme used. The hydrolysates obtained by alcalase and pepsin showed antioxidative potential whereas flavourzyme hydrolysates did not demonstrate these activities. Reducing power and 2,2′-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) scavenging activity of cucurbitin hydrolysate were positively related to DH. The highest antioxidant activity was found in the hydrolysate obtained by alcalase at DH 25.6 % [reducing power of 0.25 ± 0.01 A700 nm and ABTS scavenging activity of 3.34 ± 0.02 mmol/L Trolox equivalent antioxidant coefficients (TEAC)]. Hydrolysis by all enzymes increased the protein solubility within the studied pH range. The best emulsion activity and stability index (EAI = 143.28 ± 3.05 m2/g and ESI = 87.5 ± 1.96 min) have hydrolysates produced by flavourzyme (DH 9.2 %) whereas alcalase produced hydrolysates with the best foaming capacity (FC = 242 ± 3.21). The results demonstrate that hydrolysates produced in the present study have good functional properties as well as antioxidant activity indicating their possible use in different food systems. 相似文献
11.
Elçin Demirhan 《Chemical Engineering Communications》2013,200(5):655-666
This study investigated the effect of enzymatic hydrolysis on the functional properties of sesame cake protein. Protein hydrolyzates from sesame cake protein were obtained by enzymatic hydrolysis using Alcalase at 50°C and pH 8.5. Water-holding capacity, oil-holding capacity, foam capacity and stability, and emulsifying activity and stability of the hydrolyzates were determined. All protein hydrolyzates showed better functional properties than the original protein. Foaming and emulsifying stability decreased as the degree of hydrolysis increased. The water-holding capacity, foaming activity, and emulsifying activity of the hydrolyzates increased with the increase in levels of hydrolysis. Enzymatic modification was responsible for the changes in protein functionality. These improved functional properties make sesame cake protein hydrolyzates a useful product in foods such as bread, cake, ice cream, meat products, desserts, and salad dressing. 相似文献
12.
Functional Properties of Protein Isolates Produced by Aqueous Extraction of De-hulled Yellow Mustard 下载免费PDF全文
Two types of protein isolates were prepared from de‐hulled yellow mustard flour by aqueous extraction, membrane processing and isoelectric precipitation. The precipitated and soluble protein isolates had 96.0 and 83.5% protein content on a moisture and oil free basis, respectively. Their functional properties were evaluated and compared with commercial soybean and other Brassica protein isolates. The soluble protein isolate exhibited high values for all properties. The precipitated protein isolate showed excellent oil absorption and emulsifying properties but poor solubility, water absorption and foaming properties due to its high lipid content (~25%). Storage temperature had limited effect on lipid oxidation, and hence the stability of the precipitated protein isolate at 25–45 °C. Flavor of wieners and bologna prepared with 2% of this isolate as binder was comparable to those prepared with soy protein isolate. 相似文献
13.
Rahimeh Safar Razavizadeh Jamshid Farmani Ali Motamedzadegan 《Journal of the American Oil Chemists' Society》2022,99(7):621-632
Enzyme-assisted extraction (EAE) of oils/fats involves the disruption of the cell wall of source material using enzymes to facilitate the release of oil. When proteases are used as the enzyme, EAE ends in the extracted oil as well as the protein hydrolysates. Herein, the EAE (using a commercial protease, Alcalase) was exploited to obtain fat and protein hydrolysates from chicken skin. Degree of hydrolysis (DH, the percentage ratio of cleaved peptide bonds), which showed a logarithmic correlation with the reaction time, was found to affect the properties of the products. As the DH increased, the peptide chain length of protein hydrolysates decreased which was confirmed by SDS-PAGE analysis. With the increase of DH, the emulsifying activity index, foaming capacity, and oil holding capacity of the hydrolysates decreased but the solubility and emulsion stability index increased (p < 0.05). The DPPH free radical scavenging activity of the hydrolysates increased with the DH up to DH = 39.62% but decreased thereafter (p < 0.05). EAE resulted in a rise in fat yield and the fat contained a higher amount of unsaponifiables and lower free fatty acids (FFA) content, as compared to the control treatment (No enzyme, 80°C, 2 h, p < 0.05). DH affected the fat yield and the unsaponifiables content of the fat, positively (p < 0.05). However, it did not affect the fat FFA content and iodine value (p > 0.05). Results obtained here showed DH can be used as an effective measure for controlling the physicochemical and functional properties of chicken skin protein hydrolysates and fat in the EAE process. 相似文献
14.
Corn gluten meal (CGM) is a protein-rich coproduct generated during corn wet milling. In this study, CGM was hydrolyzed using Neutrase protease for 1 and 3 hours, respectively, to obtain antioxidative corn gluten meal protein hydrolysates (CGMPH), which could be a potential antioxidant in various products to retard lipid oxidation. Our objective was to evaluate the emulsion properties and oxidation stability of oil-in-water emulsions containing different types (1-hour and 3-hour hydrolysates) and amounts of CGMPH. The results showed that the emulsions with CGMPH had significantly improved oxidative stability than the control based on both peroxide value and thiobarbituric acid reactive substance (TBARS) analysis. The emulsion with higher concentration of CGMPH (e.g., 5 mg mL−1) showed more effective inhibition on lipid oxidation. The emulsion turbidity of 1-hour CGMPH at 2.5 mg mL−1 had a lower value than that of other emulsions, and overall, the turbidity for 3-hour CGMPH had a slightly higher value than that with 1-hour CGMPH. Addition of CGMPM did not affect emulsion morphology and droplet sizes. Zeta potential analysis showed that emulsions with 1-hour hydrolysate had more negative charges with better emulsion stability than that with 3-hour hydrolysate at the same pH. In conclusion, the CGMPH were able to inhibit lipid oxidation in reducing the formation of hydroperoxides and TBARS, and could be a potential functional antioxidant for food emulsion applications. 相似文献
15.
16.
Jatropha curcas is a multipurpose tree, which has potential as an alternative source for biodiesel. All of its parts can also be used for human food, animal feed, fertilizer, fuel and traditional medicine. J. curcas seed cake is a low-value by-product obtained from biodiesel production. The seed cake, however, has a high amount of protein, with the presence of a main toxic compound: phorbol esters as well as anti-nutritional factors: trypsin inhibitors, phytic acid, lectin and saponin. The objective of this work was to detoxify J. curcas seed cake and study the toxin, anti-nutritional factors and also functional properties of the protein isolated from the detoxified seed cake. The yield of protein isolate was approximately 70.9%. The protein isolate was obtained without a detectable level of phorbol esters. The solubility of the protein isolate was maximal at pH 12.0 and minimal at pH 4.0. The water and oil binding capacities of the protein isolate were 1.76 g water/g protein and 1.07 mL oil/g protein, respectively. The foam capacity and stability, including emulsion activity and stability of protein isolate, had higher values in a range of basic pHs, while foam and emulsion stabilities decreased with increasing time. The results suggest that the detoxified J. curcas seed cake has potential to be exploited as a novel source of functional protein for food applications. 相似文献
17.
Jesus Palomino Oviedo Robert Metz John Schulz Ralf‐Peter Tressel Frank Pudel 《化学,工程师,技术》2014,86(8):1249-1259
Protein samples of rapeseed were prepared with different compositions as protein isolate, protein concentrate and acetylated protein concentrate. They showed functional properties which are consolidated in the coating. The manufactured protein samples were tested in a pilot‐scale paperboard coating plant. The results indicated that the use of rapeseed proteins in the coating preparation is technically feasible and that the color and roughness of the coated paperboard show no negative effect on the quality. Industry printing experiments with this coated paperboard achieved the standard quality. 相似文献
18.
Rapeseed is one of the main sources of vegetable proteins worldwide. After oil extraction the protein enriched rapeseed meal is used as it is exclusively for animal feeding, having a low added value. This Special Feature describes a novel technology to produce pure rapeseed proteins. The purification scheme consists of gentle oilseed processing, aqueous protein extraction, precipitation of cruciferin and expanded bed adsorption ion exchange chromatography for isolation of pure napin. The purity of the resulting napin is >98%, and the purity of cruciferin is >95%. With the same methodology but appropriately modified process conditions a defined protein mix consisting of about 56–57% napin and 43–44% cruciferin is obtained. In comparison with egg albumin, the functional properties of napin showed better (for thermal stability) or comparable properties (for solubility, film formation, emulsion stability) and thus napin could replace animal albumins in various applications. Cruciferin and the blend with napin possess excellent foaming properties. 相似文献
19.
Optimization of the Aqueous Enzymatic Extraction of Rapeseed Oil and Protein Hydrolysates 总被引:3,自引:0,他引:3
Shao Bing Zhang Zhang Wang Shi Ying Xu 《Journal of the American Oil Chemists' Society》2007,84(1):97-105
An aqueous enzymatic extraction method was developed to obtain free oil and protein hydrolysates from dehulled rapeseeds.
The rapeseed slurry was treated by the chosen combination of pectinase, cellulase, and β-glucanase (4:1:1, v/v/v) at concentration
of 2.5% (v/w) for 4 h. This was followed by sequential treatments consisting of alkaline extraction and an alkaline protease
(Alcalase 2.4L) hydrolysis to both produce a protein hydrolysate product and demulsify the oil. Response surface methodology
(RSM) was used to study and optimize the effects of the pH of the alkaline extraction (9.0, 10.0 and 11.0), the concentration
of the Alcalase 2.4L (0.5, 1.0 and 1.5%, v/w), and the duration of the hydrolysis (60, 120, and 180 min). Increasing the concentration
of Alcalase 2.4L and the duration of the hydrolysis time significantly increased the yields of free oil and protein hydrolysates
and the degree of protein hydrolysis (DH), while the alkaline extraction pH had a significant effect only on the yield of
the protein hydrolysates. Following an alkaline extraction at pH 10 for 30 min, we defined a practical optimum protocol consisting
of a concentration of 1.25–1.5% Alcalase 2.4L and a hydrolysis time between 150 and 180 min. Under these conditions, the yields
of free oil and protein hydrolysates were 73–76% and 80–83%, respectively. The hydrolysates consisted of approximately 96%
of peptides with a MW less than 1500, of which about 81% had a MW less than 600 Da. 相似文献
20.
Composition, Structure and Functional Properties of Protein Concentrates and Isolates Produced from Walnut (Juglans regia L.) 总被引:1,自引:0,他引:1
In this study, composition, structure and the functional properties of protein concentrate (WPC) and protein isolate (WPI) produced from defatted walnut flour (DFWF) were investigated. The results showed that the composition and structure of walnut protein concentrate (WPC) and walnut protein isolate (WPI) were significantly different. The molecular weight distribution of WPI was uniform and the protein composition of DFWF and WPC was complex with the protein aggregation. H(0) of WPC was significantly higher (p < 0.05) than those of DFWF and WPI, whilst WPI had a higher H(0) compared to DFWF. The secondary structure of WPI was similar to WPC. WPI showed big flaky plate like structures; whereas WPC appeared as a small flaky and more compact structure. The most functional properties of WPI were better than WPC. In comparing most functional properties of WPI and WPC with soybean protein concentrate and isolate, WPI and WPC showed higher fat absorption capacity (FAC). Emulsifying properties and foam properties of WPC and WPI in alkaline pH were comparable with that of soybean protein concentrate and isolate. Walnut protein concentrates and isolates can be considered as potential functional food ingredients. 相似文献