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1.
《Food chemistry》1996,57(2):191-196
Protein solubility studies showed that the protein of Caryodendron orinocense flour was soluble at both acidic and basic pH, and NaCl (0.5 m) increased the solubility of all flours tested. The water absorption capacity was less, while the oil absorption was higher for Caryodendron flour than soybean flour. Both flours presented similar emulsion capacity and stability, while the foaming capacity was much smaller for Caryodendron flours than soybean flour; NaCl increased the foaming capacity of soybean flour; these results might be due to differences in protein concentration. NaCl concentrations greater than 0.25 m increased the emulsifying activity in Caryodendron flours, but did not influence the emulsion stability. The lowest gelation concentration and temperature of gelling were similar to that of soybean flour. These results suggest that Caryodendron flour might have some similar uses as soybean flour in the food industry.  相似文献   

2.
Summary The proximate composition and functional properties of raw and heat-processed velvet bean (M ucuna pruriens (L.) DC. var utilis ) flours were studied. The flours were prepared by soaking raw beans for 14 h, boiling for 30 min (heat-processed), manual dehulling, oven-drying (65 °C) and milling. The heat-processed flour contained 6.8% moisture, 24.3% protein, 4.9% fat, 1.3% crude fibre, 3.5% ash and 61.2% carbohydrate. The flour was rich in potassium (125 mg/100 g), zinc (9.8 mg/100 g) and phosphorus (361 mg/100 g). Differences in proximate and mineral composition of raw and heat-processed flours were not significant. The flours showed minimum protein solubility at pH 4.5 and formed reasonably stable emulsions and foams. Compared to raw flour, heat-processed flour had better water and fat absorption capacities, but lower protein solubility, emulsion and foam capacities. The flours have potential for food product development.  相似文献   

3.
Field pca and faba bean proteins are rich sources of lysine, and air classification of the pin milled flours essentially doubled the protein contents in the protein fractions. The proteins in these flours and protein fractions were highly soluble at acid pH and exhibited only a narrow range of insolubility at pH 4–5. Water holding and oil absorption capacities increased in proportion to protein contents of the flour, protein fraction, and isolate of each legume, including soybean flour and isolate, but oil emulsification properties were uniformly high among all products. The protein fractions exhibited excellent whipp-ability and foam stability compared to soybean controls, and their promising functional properties suggested potential applications in meat emulsions, beverages and bakery products.  相似文献   

4.
Emulsifying and foaming properties were determined for coriander protein products (defatted flour and protein concentrate) at pH 4.0, 7.0 and 9.0 and the results compared with those obtained for defatted soybean flour. Mean oil droplet size and interfacial protein concentration was smallest for emulsions (∼17% oil, v/v) stabilized by the coriander protein concentrate, when compared to the coriander and soybean flours. Polypeptide composition of the interfacial protein membrane of the emulsions was different from the polypeptide composition present in the respective coriander flour and protein concentrate. In contrast, soybean flour-stabilized emulsions contained similar polypeptide composition to that of the flour. Soybean flour formed the greatest amount of foams at pH 4.0, 7.0 and 9.0 followed by the coriander flour, which had greater amounts of foam at pH 4.0 and 5.0. The foam stability of both the coriander flour and protein concentrate were significantly (P⩽0.05) less than those of the soybean flour. It was concluded that the reduced level of non-protein components in the coriander protein concentrate favoured increased surface activity at the oil–water interface but not at the air–water interface.  相似文献   

5.
Water and fat absorption, gelation, protein solubility, emulsification and foam capacities of flours from citron, orange and mandarin seeds were determined. The protein solubility of the flours was increased as sodium chloride concentration increased up to 0.8 M for citron, mandarin and mixture seed flours and 1 M for orange seed flour, then decreased at higher concentrations. The minimum solubility was sharp for mandarin and orange seed flours, while, it was broader for mixture and citron seed flours. The least concentration for forming gel was 6%, 6.5% and 7% for mandarin, orange and both citron and mixture seed samples, respectively. The flours of orange and mandarin seeds were the highest and lowest in water absorption capacity. Also, the highest value of fat absorption capacity was noticed for citron and lastly for mandarin on flour basis. The emulsification and foam capacity-pH patterns were similar to protein solubility-pH profiles for all citrus seed flours. Foam capacity of mandarin and mixture seed flour were lower than that of citron and orange seed flours. The emulsification and foam capacities patterns in sodium chloride solution showed an increase up to 0.6 M and then decreased in all citrus seed flours. Foam stability of citrus seed flours was increased with sodium chloride concentration up to about 0.6 M and then decreased. The foam stability of all citrus seed flours at pH 4.5 was very poor but at pH 2, it was comparable to that at pH 8.  相似文献   

6.
Full fat and defatted cashew kernel flours were prepared and analysed for their physicochemical and functional properties. There were significant increase in protein and carbohydrate contents of the flour as a result of defatting. The defatted flour possessed higher Ca, P, Na and K contents. It had improved gel strength, foaming and emulsion properties. Foam capacity for the full fat and defatted flours increased from 42% to 50% and 55% to 57% with increased NaCl concentration up to 0.25 and 0.05  m , respectively. The foam capacity and stability of the flours were also pH dependent. The emulsion activity and stability of both flours decreased with increasing NaCl concentration. Minimum and maximum protein solubility were at pH 4 and 8, respectively for the full fat and defatted flours. These results suggest that defatted cashew flour may have potential application as a functional ingredient and as a supplement in foods.  相似文献   

7.
The effects of domestic cooking on the content of amino acids and antinutrients of Phaseolus angularis, Phaseolus calcaratus and Dolichos lablab seeds were evaluated. Heat treatment (30 min) caused significant declines (P<0·05) in the apparent recovery of most of the essential amino acids except leucine and phenylalanine for P angularis, and except phenylalanine for P calcaratus. Cooking D lablab seeds (60 min) also resulted in a significant reduction (P<0·05) in the apparent recovery of all the essential amino acids except leucine, histidine, lysine and threonine. Increased cooking time for P angularis (60 min), P calcaratus (60 min) and D lablab (120 min) led to a lower apparent recovery of methionine (28·9–31·6%) and cystine (17·1–19·3%). Even with increased cooking times, the total essential amino acid levels in all three cooked seeds remained higher than that of the FAO/WHO requirement, except for methionine and cystine. Cooking (60 min) was found to be effective in reducing the tannin contents of P angularis, P calcaratus and D lablab seeds by 70·6, 64·6 and 74·6%, respectively. Upon cooking, phytate and trypsin inhibitory activity in different seeds were also reduced to different extents depending on the cooking times. ©1997 SCI  相似文献   

8.
Functional properties of defatted and detoxified Madhuca (Madhuca butyraceae) seed flours were determined and compared with those of soybean flour. Soybean and detoxified Madhuca flours had higher water absorption capacities than defatted Madhuca flour. Due to the presence of saponins, the defatted Madhuca flour showed higher foaming capacity than the soybean and detoxified Madhuca flours.  相似文献   

9.
Full‐fat and defatted Moringa oleifera kernel flours were analysed for their functional properties. The effect of pH and NaCl concentrations on the functional properties of the flours was investigated following standard procedures. The protein content of full‐fat and defatted flour was 36.18 and 62.76 g/100 g, respectively. The concentrations of other proximate constituents of the defatted flour were higher than those of the full‐fat flour. Nitrogen solubility was lowest at pH of 4.0 and 9.0, respectively, with maximum solubility occurring at pH of 6.0. Defatting increased the water absorption and fat absorption capacities of Moringa oleifera kernel flour. The foaming capacity and foam stability of the defatted flour were 86.0% and 82.0 mL, whereas that of full‐fat flour were 20.6% and 18.5 mL respectively. The defatted flour showed better emulsification (97.2 mL g?1) than full‐fat flour (66.0 mL g?1). The least gelation concentration of the defatted and full‐fat flours was 14% and 16% (w/v) respectively. Moringa oleifera kernel flour can be a valuable source of vegetable protein in fortified food products formulation.  相似文献   

10.
Nutritionally potential under explored wild legumes viz., Canavalia cathartica and Canavalia maritima are widely distributed in mangroves and sand dunes, respectively, in Southwest coast of India. Physicochemical, functional and cooking properties of dried seeds of these legumes have been evaluated. Seeds and cotyledons of C. cathartica are larger and possessing higher hydration and swelling capacity than that of C. maritima indicating higher permeability and softness. The crude protein of C. maritima and C. cathartica were found to be higher than common pulses. The pH vs. protein solubility profile was almost similar with minimum solubility at pH 4 (27.8–28.1%). C. maritima showed higher oil absorption capacity (1.53 ml/g) as well as water absorption (0.1 M) capacity. The gelation capacity was minimal at 0.1 M NaCl and pH 4 for both the seed flours. Addition of carbohydrates (starch, lactose, maltose and sucrose) reduced the lowest gelling capacity of C. maritima except for maltose in C. cathartica. Emulsifying activity (EA) and emulsifying stability (ES) diminished with increasing concentration of flours. Minimum EA and ES were attained at pH 4 and maximum at pH 10 in both seed flours. Maximum EA for C. cathartica and C. maritima (62% vs. 72.6%) was attained at 0.4 M NaCl. The ES vs. flour concentration, pH and ionic strength profiles did not differ much between C. maritima and C. cathartica. Peak foam capacity (FC) and stability (FS) were achieved at 6% (w/v) of C. maritima flour, while the same was attained at 8% (w/v) of C. cathartica. The FC and FS of the seed flours improved with increasing pH (pH 2–10). C. maritima flour exhibited the better FC (27.7%), while C. cathartica exhibited better FS (44.42%) at pH 10. Although highest FC was attained at 0.4 M NaCl in both flours, C. maritima was found to be superior (30.5% vs. 28.5%). The flour of C. maritima attained the highest FS at 0.2 M NaCl than C. cathartica (0.4 M NaCl). The minimum cooking time for cotyledons of C. cathartica was more and higher gruel solid loss was reported due to its high L/B ratio. The Pearson correlation coefficients revealed that functional properties of seed flours vary due to their chemical composition.  相似文献   

11.
The nutrient composition, antinutritional factors and flour functionality of cowpea and horse gram flours were evaluated in comparison to chickpea flour characteristics. Protein content of these flours was in the range of 22.5−24.1%. Fat content was highest in chickpea (4.8%) and lowest in horse gram (1.4%). Resistant starch and phytic acid were significantly higher in cowpea flour. Compared to chickpea and cowpea, horse gram has more carbohydrate, dietary fibre, polyphenols and trypsin inhibitor activity and less oligosaccharides. Horse gram and chickpea flours had the highest water and oil absorption capacities with values of 148.1% and 109.3%, respectively. Although emulsion activity (58.1%) and stability (52.0%) were superior in horse gram, foaming capacity and foam stability were significantly higher in chickpea and cowpea flours, respectively. These results suggest the potential utility of cowpea and horse gram flours as substitutes for chickpea flour in some food products formulations.  相似文献   

12.
Influence of grain germination on functional properties of sorghum flour   总被引:1,自引:0,他引:1  
A Sudanese sorghum cultivar (Fetarita) was germinated for five days and protease and amylase activities were measured every 24 h. Results showed that flour obtained from the 3rd germinated sorghum grain had high protease and amylase activities. The functional properties of flours derived from the germinated sorghum seeds were studied and ungerminated seeds were used as a control. Germinated samples had a higher protein solubility compared with the control, and the highest solubility occurred at pH 6. Germination also increased the protein solubility index of sorghum flour. Germinated sorghum flour had a least gelation concentration of 8% compared with 18% for the control. The bulk densities of germinated flours were lower compared to the ungerminated one. Water and oil capacities were increased by germination from 131.34% and 90.56% to 141.64% and 108%, respectively after three days of germination. The emulsifying activities and stabilities of the germinated samples increased significantly. In addition, germination improved the foamability of sorghum flour from unfoam flour to a flour with foam after three days of germination; and the foaming capacity and stability increased significantly with increasing germination time. Thus, the study indicated that germination improved the functional properties of sorghum and it would be possible to design new foods using germinated sorghum.  相似文献   

13.
The physicochemical, functional and pasting properties of whole flours from pinto bean, lima bean, red kidney bean, black bean, navy bean, small red bean, black eye bean, mung bean, lentil and chickpea were investigated. Significant differences in physicochemical characteristics and functional properties were observed (P < 0.05). Bulk densities, water absorption indices, water solubility indices, oil absorption capacities, emulsion activities, and emulsion stabilities ranged from 0.543 g/mL to 0.816 g/mL, 4.09 g/g to 6.13 g/g, 19.44 g/100 g to 29.14 g/100 g, 0.93 g/g to 1.38 g/g, 61.14%–92.20%, and 84.15%–96.90%, respectively. Phaseolus legume flour exhibited higher water absorption capacity, oil absorption capacity, emulsion activity, and emulsion stability compared with other kinds of legume flour. Pasting properties were significantly different (P < 0.05). Pasting temperatures and the peak, final, and setback viscosities of the flours ranged from 73.2 °C to 83.0 °C, 96.2 RVU to 216.8 RVU, 118.5 RVU to 243.8 RVU, and 28.3 RVU to 103.2 RVU, respectively.  相似文献   

14.
The objective of this research was to study the chemical compositions, functional properties, and microstructure of partially defatted flours (PDF, 12–15% fat, dry basis (db)) and totally defatted flours (TDF, 1% db fat) from three macadamia cultivars, PY 741, DS 344, and DS 800, grown in Northern Thailand. The defatted flours were high in protein (30.40–36.45% db) and carbohydrate (49.29–57.09% db). For each macadamia cultivar, while emulsion activities and emulsion stabilities of the TDF tended not to be different from those of the PDF (p > 0.05), TDF had significantly greater water absorption capacities (WAC), oil absorption capacities and foaming capacities (FC), but had significantly lower foaming stability (FS) than the PDF (p ? 0.05). The TDF from PY 741 cultivar possessed the highest WAC and FC but the lowest FS. The variation in the functional properties of the defatted flours could mainly arise from the difference in the quantity and characteristics of the proteins in the flours. Structure determination of macadamia flours showed that the proteins bodies and starch granules were embedded in kernel tissues. The starch granules were oval and approximately 10 μm in diameter.  相似文献   

15.
M. Siddiq  R. Ravi  K.D. Dolan 《LWT》2010,43(2):232-237
Many varieties of dry beans (Phaseolus vulgaris L.) are available with entirely different physico-chemical and sensory characteristics. Selected dry bean varieties (red kidney, small red kidney, cranberry and black) were processed into flour and analyzed for the physico-chemical and functional characteristics. The bulk density of the beans flours varied significantly (p < 0.05) from 0.515 g/ml for black bean flour to 0.556 g/ml for red kidney bean flour. The small red kidney bean flour had the highest water absorption capacity (2.65 g/g flour) while black bean flour showed the lowest at 2.23 g/g flour. Significant differences were observed for oil absorption capacities of bean flours, which ranged from 1.23 g/g for small red kidney bean flour to 1.52 g/g for red kidney bean flour. The bean flours emulsion capacity and stability and foaming capacity and stability also varied significantly and was variety-dependent. The highest apparent viscosity, 0.462 Pa.s, was recorded for small red kidney bean flour whereas black bean flour exhibited the lowest value of 0.073 Pa.s at 30 g/100 ml water content in the flour dispersions. The force-deformation curves for doughs from different bean flours showed that black bean flour had the highest peak force or hardness value of 90.7 N followed by doughs from cranberry, small red kidney and red kidney bean flours. The results of this study offer useful data on bean flours' potential uses in different food products.  相似文献   

16.
《Food chemistry》2001,74(4):455-462
Protein isolates were prepared from both sweet and bitter lupin seed flours by two different methods, i.e. by alkaline water extraction/isoelectric precipitation (P1) and by micellisation (MI), and studied with regard to nutritional quality and functional properties. Protein solubility of both lupin seed flours was increased as sodium chloride concentration increased up to 1.0 M, then decreased. The minimum protein solubility of bitter lupin seed flour was quite sharp at pH 4.5, while it exhibited a broad pH range of 4.3–4.9 for sweet lupin seed flour. No significant (P<0.05) differences were found between any isolates in their dry matter, fiber, lipids and moisture contents. Isolates-PI from both sources had significantly (P<0.05) higher crude protein and ash contents than their isolates-MI. Bitter and sweet isolates-PI had lower values of total essential amino acids and higher values of tyrosine, phenylalanine, threonine, tryptophan and valine than isolates-MI. There was no significant (P>0.05) difference between bitter isolates in their alkaloid contents, while both sweet lupin isolates were free of total alkaloids. Bitter lupin isolate-PI had significantly (P<0.05) lower tannins, but sweet lupin isolate-MI had a significantly (P<0.05) higher phytic acid content than other isolates. Isolates-MI from both sources had higher chemical scores than their isolates-PI. The first and second limiting amino acids were total sulfur amino acids and valine, respectively, for all types of isolates. Sweet lupin isolate-MI had a higher essential amino acid index and protein efficiency ratio than other isolates. The protein solubility index, fat absorption and emulsification capacities of both isolates-MI were significantly (P<0.05) higher than their isolates-PI. Both sweet lupin isolates had significantly (P<0.05) higher water absorption capacity than bitter lupin isolates. Sweet lupin isolate-MI had significantly (P<0.05) higher foam capacity and foam stability than other lupin isolates.  相似文献   

17.
E H Rahma 《Die Nahrung》1988,32(6):577-583
Faba beans (Vicia faba) were germinated at room temperature for 3 and 6 days respectively. The effect of germination on the protein fractions, protein solubility index, PAGE pattern and some functional properties i.e. emulsification capacity (EC), foaming capacity (FC), foam stability (FS), water and fat absorption capacities of the flour was studied. Germination decreased albumins, globulins and prolamins at different levels but non protein nitrogen and glutelins were increased. The protein solubility index was high at both extreme pH values with an isoelectric point (IP) at pH of 4.4-4.5. The solubility of the protein slightly increased due to germination at all the pH values. PAGE pattern revealed on obvious dissociation and utilization for both fast and slow moving protein fractions during germination. Emulsification and foaming properties vs pH profile were similar to the pattern of solubility vs pH. Both properties were high at acidic and alkaline pH's and the minimum values were at pH 4 to 5. Germination process improved EC, FC and FS of the flour in comparison with that of dry bean flour. Water absorption of faba bean flours was improved during germination but the fat absorption markedly decreased.  相似文献   

18.
PROCESSING AND FUNCTIONAL PROPERTIES OF YAM BEANS (SPHENOSTYLIS STENOCARPA)   总被引:1,自引:0,他引:1  
The proximate and selected functional properties of five flours from yam bean (YB) made after the grains were not processed (raw) and processed as boiled, fermented, roasted and malted, were determined. The functional properties were water and fat absorption, gelation, emulsification and whippability. An improvement was observed for protein content of flours processed beans compared to raw flour. Fermentation improved the oil content of the flour. The emulsifying and foaming capacities (50.7 and 40.20%, respectively) observed for raw flour were significantly higher than those for the flours from processed bean. Gelation was significantly (P < 0.05) increased and decreased by fermentation and malting of the bean, respectively. The water absorption capacities ranged from 131.9% in raw flour to 218.8% in flour boiled beans. There were no significant (P > 0.05) differences in the fat absorption capacities of all flours except for the one of fermented beans (0.40 mL/g), which was significantly lower than the value (0.73 mL/g) obtained for the flour from boiled beans. Although a high foaming capacity was observed for raw flour, it was less stable when compared with that of the processed bean flours. Overall, YB flour was found to exhibit good functional properties, and has a great potential for use as an ingredient in selected food systems.  相似文献   

19.
The effects of seed treatments, including cooking, popping germination and flour air classification, on the functional properties and antinutritional factors of Amaranthus caudatus and Amaranthus cruentus seeds were studied. Thermal treatments increased the water absorption with a maximum value of 5.1 and 6.3 g g−1 in flour of popped seeds of both species. Generally, fat absorption increased after the treatments. Air classification and germination followed by drying at low temperature increased the foam stability of the flours, while thermal treatment and germination followed by drying at higher temperatures reduced the foam stability. All treatments except air classification decreased the emulsion stability. Also, all treatments except germination followed by drying at 30 °C increased the flour dispersibility, whereas the soluble nitrogen index was increased in the germinated seed flours and decreased in thermal treated seeds and air‐classified flours. Air classification increased the contents of phenolic compounds and phytate and decreased the contents of enzyme inhibitors, whereas the thermal treatments reduced the contents of phenolic compounds, phytate and enzyme inhibitors to a greater extent for cooking than for popping. Germination followed by drying reduced the level of phenolic compounds, phytate and enzyme inhibitors. Copyright © 2006 Society of Chemical Industry  相似文献   

20.
《Food chemistry》2005,92(4):681-691
Albumin (ALBa) and globulin (ALBg) fractions of African locust bean were isolated and the functional properties were compared with its defatted (ALBdf) and undefatted flours (ALBf). Albumin had minimum % solubility (56.7%) at pH5, while minimum solubility was observed at pH4 for globulin and the flours. In all the samples studied, maximum solubility was observed at pH 10. A pH-dependent gelation study revealed that all of the samples had the highest least gelation concentration at pH10 apart from ALBf which had 16% w/v LGC at pH 2. Initial increase in ionic strength of the medium, to 0.4 and 0.6 M, enhanced the gelation capacity of protein fractions and flours, respectively, while further increase in ionic strength reduced it. Oil absorption capacity was maximal in ALBa while ALBf had the least value of 1.05 ml/g. Initial increase in ionic strength, up to 0.4 M, increased the water absorption capacity (WAC) of albumin fractions while WACs of the globulin fraction and flours were reduced when the ionic strength of the media reached 0.4 M. Foam capacity increased as the concentration of protein solution increased but was reduced by 6% w/v in ALBf. Initial increase in ionic strength enhanced both foam capacity and stability. Maximum EA was observed at pH 10 in all samples apart from ALBf, which reached a peak EA value at pH 2. ES (emulsion stability) was maximal at pH 10 for ALBa and ALBg while the same values were observed for ALBdf and ALBf at pH 2 and 10. Increasing the ionic strength, to 0.4 M, enhanced the EA and ES of ALBa while further increase in ionic strength, to 0.7 M, improved EA of ALBf but reduced the ES. Both EA and ES of ALBf reached peak values in 0.2 M solutions but no fixed pattern was observed in the response of ALBdf to various ionic strengths of the solutions.  相似文献   

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