Fat Absorption Capacity Research Articles

Functional properties of meal products of the nigerian ‘red skin’ groundnut (arachis hypogaea L.)

AbstractThree products were prepared from the Nigerian red skin groundnuts; undefatted flour (UGF), hexane‐extracted defatted flour (DGF), and a protein concentrate made by isoelectric centrifuging (GPC). Their functional properties were examined and compared with those of egg white powder and yolk to characterise their potential use in food preparations. The GPC performed better in functional properties than DGF and UGF. Emulsification capacity was higher than that of UGF and DGF but comparable to that of egg yolk. A 5% dispersion whipped better than egg white powder and produced more stable foams over a 3‐h period. Both water and fat absorption capacities were better and a 10% aqueous dispersion of the GPC was more viscous than similar dispersions of DGF and UGF respectively. Least gelation concentrations were 5, 3 and 4% for GPC, DGF and UGF. The high emulsification capacity, water and fat absorption capacities suggest that the GPC could be used in processed meat products, confections and beverages while the good whipping properties point to its potential use in products like meringue, bread and hot cakes.

Functional properties of guar (Cyamopsis tetragonoloba) meal protein isolates

Functional properties of protein isolates obtained from detoxified guar meals were compared with those of defatted guar meal protein isolate. All samples exhibited U-shaped nitrogen solubility vs. pH profiles with max. solubilities (80%) at extreme acidic and alkaline regions and min. solubility (2%) at pH 5. Protein isolates from aqueous alcohol-extracted and autoclaved meals had lower water absorption capacities (74-98 g/100-g sample) while 1 and 0.25 N HCl-extracted meal isolates had significantly higher values of 187 and 180 g/100-g sample, resp. Fat absorption capacities (g/100-g sample) of the various isolates obtained from treated flours were in the range 105-133 while that of defatted meal isolate was 108. Foam capacity (% vol. increase) of the 2-propanol-extracted meal isolate was 150 compared to a value of 125 for the control while the other detoxified meal isolates had lower foam capacities. Foam stability (% foam vol.), at 30 min after whipping, of the various samples ranged from 48 to 63, the highest value being for the defatted meal isolate. The defatted guar meal isolate had an emulsification capacity (ml of oil emulsified/g of sample) of 65 while the values for the other isolates ranged from 56 to 72.

Functional properties of poppy seed meal

Water and fat absorption capacity, emulsification capacity, and foam capacity and stability of defatted poppy seed meal were determined and compared with those of soybean meal. Poppy seed meal had lower water absorption capacity but higher fat absorption capacity than soybean meal. The emulsification capacity was almost the same as that of soybean meal in the range pH 4.0-7.0. The foam capacity and stability values were inferior to those of soybean meal at all the pH values. Incorporation of NaCl up to 0.1M improved emulsification capacity of poppy seed meal and foam capacity up to 0.2M .

In vitro digestibility, physico-chemical and functional properties of apricot kernel proteins

The chemical composition of apricot kernel flour and protein isolates was determined. The flour contained about 48% protein, mainly albumins. The solubility at different pH values showed a single isoelectric point at pH 4 and the solubility increased in both acidic and alkaline pH. The digestibility of the protein was high in the pepsin-pancreatin system and quite low when pepsin or trypsin was used. The ultraviolet absorption spectrum of the proteins of both flour and protein isolates was typical of those of other vegetable proteins. The polyacrylamide gel electrophoresis pattern of apricot kernel proteins consisted of four major protein fractions. Water and fat absorption and emulsification capacity of flour and protein isolates were quite comparable with that of soybean. Detoxified apricot kernel flour and protein isolates appear to be good sources of protein for food products.

Effect of heat treatment on the functional properties of linseed meal

N solubility, fat and water absorption capacity, bulk density, foam capacity and stability, and emulsification capacity of raw linseed meal (LM) and water-boiled linseed meal (WB) were determined and compared with those of defatted soybean meal (SM). Water boiling reduced the N solubility of linseed meal in water, NaCl, and sodium hexametaphosphate. The water absorption capacity of LM was 345 g compared to 443 g of WB whereas the fat absorption capacity of LM and WB was 236 and 167 g/100 g of flour, resp. On the other hand, SM exhibited lower water (305 g) and fat absorption (167 g) than LM. SM showed higher foam capacity and emulsification capacity than LM. The foam stability of LM was better than that of SM. Heat processing diminished the foam-capacity and stability and emulsification capacity of linseed meal.

Effect of Acetylation and Succinylation on the Functional Properties of Winged Bean (Psophocarpus tetragonolobus) Flour

ABSTRACTWinged bean flour was acylated to various degrees and changes in functional properties were monitored. Nitrogen solubility in water increased up to ?80% acylation and then decreased. Water absorption capacity increased continuously with the extent of acylation. The fat absorption capacity of the acetylated flour increased up to ?30% acetylation and then decreased while that of the succinylated flour remained unchanged. Emulsion capacity showed the same trend as nitrogen solubility in water. Foam capacity increased due to acylation but foam stability decreased. Bulk density of the acetylated flour increased up to ?80% acetylation and then decreased. Succinylated flour had higher bulk density at all levels of succinylation.

Functional Properties of Protein Products of Mass Cultivated Blue-Green Alga Spirulina Platensia

Water and fat absorption capacity, Emulsification Capacity (EC), Foaming Capacity (FC) and Foaming Stability (FS) of flour and protein concentrate of Spirulina cells were compared with those of soybean meal both as a function of pH and NaCI concentration. Water and fat absorption capacities of Spirulina flour were 220g and 19Og/lOOgo f sample respectively; those of soybeanm eal were 230g and 12Og/lOOgo f sample. Protein concentrate had a lower water absorption capacity, higher fat absorption capacity than its flour. It had higher EC and similar FC. Spirulina flour had similar EC and FC to that of soybean meal. The FS of flour (18%) and protein concentrate(2 7%) was poor when comparedt o soybeanm eal (55%).

Effect of Dehydration Methods on the Functionality of Plant Protein Concentrates

AbstractThe significance of different dehydration methods for rice bran protein and soy protein coagulates on composition and functionality of the resulting protein concentrates was investigated. Minor compositional differences were found between the freeze‐, spray‐ or drum‐dried samples. Protein solubility data indicated limited effects of dehydration methods on heat coagulated samples but significant reduction of protein solubility by drum drying was found in the case of soy protein coagulated at room temperature. Water absorption capacity and emulsion properties were significant affected by dehydration methods but no consistent trends could be observed for fat absorption capacity. A significant increase of specific bread loaf volume, relaxation time of doughs and in some cases deformation of protein fortified samples was detected from freeze‐dried to drum‐dried samples. In general the effects of dehydration methods on protein functionality were more consistent for heat coagulated rice bran protein than for soy protein concentrates processed at ambient temperatures.

Functional Properties of Raw and Heat Processed Winged Bean (Psophocarpus tetragonolobus) Flour

ABSTRACTNitrogen solubility, emulsification capacity, foam capacity, fat and water absorption capacity of raw and heat‐processed winged bean flour were compared with those of raw soy flour, both as a function of pH and NaCl concentration. Nitrogen solubility vs pH profile showed only one minimum, at pH 4.5. Heat processing of winged bean flour lowered nitrogen solubility. Water and fat absorption capacity of winged bean flour were 2.1 g/g and 1.4 g/g, respectively; those of raw soy flour were 3.1 g/g and 1.2 g/g. Heat processing increased water and fat absorption capacity of winged bean flour by 38% and 57%, respectively. Emulsification capacity of raw winged bean flour was higher than that of raw soy flour by about 30–60% depending on the pH. Heat processing diminished emulsification and foam capacity of winged bean flour by about 35% and 18%, respectively. Incorporation of NaCl up to 0.4M improved emulsification capacity of winged bean flour and foam capacity up to 0.2 M.

Functional Properties of Guar Seed (Cyamopsis tetragonoloba) Meal Detoxified by Different Methods

ABSTRACTFunctional properties of guar meal detoxified by autoclaving, extraction with aqueous ethanol, methanol, isopropanol or dilute hydrochloric acid were compared with those of defatted soy meal. Acid washed and the autoclaved meals gave low nitrogen solubility (NS) at pH 7.0. Detoxified guar meals had greater water absorption capacity (WAC) than the raw meal, while defatted soy meal was far superior to defatted guar meal. Fat emulsification capacity (EC) showed a similar trend as NS and fat absorption capacity (FAC) inversely correlated with the bulk density of samples. Autoclaved guar meal had higher EC and FAC than the alcohol or acid extracted meals. The foam capacity (FC) and foam stability (FS) of the 80% isopropanol extracted guar meal were the highest among the samples.

Influence of An Addition of Textured Milk Proteins Upon Physicochemical Properties of Meat Mixtures

ABSTRACTMeat systems consisted of beef haunch (pH 5.63) in which textured milk proteins were substituted at: 0, 10, 20, 30, 40, 50, 75, and 100%. The effects of these substitutes on the physicochemical properties of ground meats were measured for products containing no salt, sodium chloride (2%), polyphosphate mixture Hamine (0.5%) and sodium chloride and Hamine together (2%+ 0.5%). Measurements included: water absorption capacity, water‐holding capacity, thermal shrinkage, consistency, viscosity, fat absorption capacity, emulsifying capacity, emulsion stability, and active acidity. Addition of textured milk proteins improved the technological adaptability of ground beef, optimum substitution depending on the type of salt. In order to improve the physicochemical properties of beef, substitution of 30% meat by textured milk proteins with addition of 2% sodium chloride, is recommended.

Fractionation and Properties of Oocystis Algal Proteins

Proteins of the alga Oocystis were fractionated, characterized and compared for their composition and functional properties plus the effect of succinylation. Extraction of Oocystis proteins by successive ammonium sulphate fractionation yielded 44% and 66% protein in the absence or presence of ascorbic acid and polyvinylpyrrolidone, respectively, indicating that the presence of oxidative enzymes and phenolic compounds may partially impair the recovery of algal proteins. Both sedimentation, velocity ultracentrifugation and electrophoretic analyses indicated that most of the algal extract proteins were of a single type (1.2S; 12,500 daltons) with the 30% fraction having higher levels of threonine, methionine and cystine.The protein contents of the various preparations ranged from 71% (ethanol fraction) to 96% (succinylated fraction). Ribonucleic acid (RNA) content in most protein preparations ranged from 6.1% (whole protein fraction) to 11.1% (isoelectric point fraction) with the concentration of lysine, leucine, valine, phenylalanine and tyrosine being high in six of the preparations. In general, except for ethanol precipitated protein, Oocystis protein samples showed good fat absorption, foaming and emulsion capacities and were soluble above pH 6.0. Ethanol precipitated proteins had a high ash content and showed good water absorption but poor emulsion capacities.There was a major reduction in RNA content (1.9%) and improvement in the solubility, water absorption, foaming capacity and viscosity by succinylation, but this process led to poor foam stability and thickening properties upon heating.The protein samples isolated from Oocystis are white and have a bland taste; these properties should permit the fortification of other foodstuffs with relatively little effect on palatability.

Removal of Polyphenols from Sunflower Meal by Various Solvents: Effects on Functional Properties

ABSTRACTThe protein and chlorogenic acid (CGA) content, nitrogen solubility index (NSI), water and fat absorption, emulsification capacity (EC), foaming capacity, and foam stability of dehulled, defatted sunflower meal treated by various solvent systems to remove polyphenols were determined. All solvent treatments resulted in increased protein content, markedly reduced the CGA content, and increased water absorption capacity (WAC). Organic solvents caused a decrease in NSI whereas water, 0.002N HCI, or 2% NaCl solution caused an increase. Aqueous ethanol extraction decreased fat absorption, emulsification, and foaming capacity. Acidic n‐butanol increased foaming capacity, multiple solvent system did not affect it and other solvents used decreased it.

Functional Properties of Guar Proteins

Water and fat absorption, emulsification capacity (EC), foaming capacity (FC), and foam stability (FS) of guar meal and protein isolate have been determined and compared with those of soybean meal and isolate. Guar meal had lower water absorption capacity, similar fat absorption capacity and greater FS and EC than soybean meal. Guar protein isolate (GPI) had lower water absorption capacity but higher fat absorption capacity than soy protein isolate (SPI). The FC and EC were similar at all pH levels, except around pH 4. However, the FS of GPI was greater than that of SPI.

Modification of Heat Coagulated Whey Protein Concentrates by Succinylation

Heat coagulated cheese whey protein concentrate was modified by reaction with succinic anhydride at pH 8 followed by isoelectric precipitation, neutralization, and freeze drying. All functional properties except whippability were improved. Succinylated whey protein concentrate dispersed readily as highly swollen particles with high viscosity. It can absorb 11 to 13 times and 2 to 3 times its weight of water and fat. It has high emulsifying capacity and can form stable emulsions at 1% usage. Gel filtration indicates extensive unfolding of the protein after succinylation. Except for a slight decrease in lysine, the amino acid composition was unaltered. Succinylation increased the protein content of the whey protein concentrate with little loss in biological value and yield. Possible application of the succinylated product would be in products which require high water and fat absorption capacities, viscosity, and emulsifying properties such as baked goods, processed meats, and dairy analogs.

Some functional properties of pea and soy bean protein preparations

AbstractThe physical and functional properties of pea and soy bean protein concentrates, and soy bean isolate were investigated. Pea protein concentrate had good lipophilic properties. High fat absorption capacity was confirmed by the small cooking weight losses of meat model systems containing oil and lard. Better functional properties of pea and soy bean protein concentrates in these model systems may be due to specific surface structure, which was evident on the SEM microphotographs. The physical and functional properties of pea protein concentrate were similar to the properties of soy bean concentrate.

COPRECIPITATION OF CHEESE WHEY WITH SOYBEAN AND COTTONSEED PROTEINS USING ACID AND HEAT TREATMENT

ABSTRACTSoybean‐ and cottonseed‐whey protein coprecipitate isolates (SIW and CIW) and coprecipitate concentrates (SCW and CCW) were all prepared using heat treatment (95°C, 15 min) at acidic pH (4.6). Soybean and cottonseed protein isolates (SI and CI) and concentrates (SC and CC) and whey protein concentrate (WC) were also prepared under similar conditions for comparison with the coprecipitates. In general, the coprecipitation resulted in acidulant savings (7–9% for SIW and CIW, 51–68% for SCW and CCW), higher nitrogen yields (24–29% for SIW and SCW, 10–17% for CIW and CCW), higher protein scores, lighter color, slightly higher solubility, lower water and fat absorption and emulsifying capacities compared with separate precipitation of the oil‐seed proteins. The whipping properties decreased in the coprecipitate isolate but increased in the coprecipitate concentrate of soybean and cottonseed. Compared with a commercial soy isolate, all coprecipitates had lower solubility, emulsifying and whipping capacities but equivalent water and fat absorption capacities.

POTATO PROTEIN CONCENTRATES: THE INFLUENCE OF VARIOUS METHODS OF RECOVERY UPON YIELD, COMPOSITIONAL AND FUNCTIONAL CHARACTERISTICS

Potato processing effluents represent a potential source of valuable protein as well as a major waste disposal problem. Potato protein is commonly recovered by heat (in excess of 90°C) with pH adjustment between 3.5 and 5.5. The present study compared yield, and some compositional, and functional characteristics of potato protein concentrate (PPC) recovered with either HCl or FeCl3 (pH 3.0, 20–22°C), or HCl/heat (pH 4.8, 98–99°C). Under pilot plant conditions, recoveries of 22.7, 36.7, and 37.5% of the crude protein (N × 6.25) were obtained with HCl, FeCl3, and HCl/heat, respectively. Crude protein content of the PPC precipitated by HCl, FeCl3, and HCl/heat were 65.6, 57.5, and 78.2% respectively. Ash and vitamin C values were higher in those PPC recovered at room temperature, with Fe content being highest in the PPC recovered with FeCl3. The nitrogen solubility of the FeCl3 precipitate, at pH 7.0, was 1.5 and more than 7 times that of the HCl, and HCl/heat precipitates, respectively. Whipping capacity of PPC was not influenced by precipitation method. The most favorable fat absorption and water absorption capacities were exhibited by the HCl and HCl/heat precipitates, respectively.

Coprecipitation of Rapeseed and Cheese Whey Proteins Using Acid and Heat Treatment

Rapeseed protein isolate (RI) and concentrate (RC) prepared with and without added cottage cheese whey (W) were compared. The products with W were called rapeseed isolate-whey coprecipitate (RIW) and rapeseed concentrate-whey coprecipitate (RCW), respectively. RIW had higher protein score and biological value, lighter color, better emulsifying, water and fat absorption capacities but lower whipping properties than RI. RCW had almost similar protein score and biological value, lighter color, lower water and fat absorption capacities but higher emulsifying and whipping properties than RC. In general, rapeseed-whey protein coprecipitation resulted in lower acidulant requirement and higher nitrogen yield than the separate precipitation of the two proteins. The amino acid pattern and some functional properties of the coprecipitates deviated from mixtures of separately precipitated rapeseed and W proteins which is suggestive of a complex interaction between the two proteins during the coprecipitation process. Compared with a soy protein isolate, the coprecipitates had poorer functionality which could be attributed to the protein denaturation which occurred during the heat treatment (95°C, 15min) involved in their preparation. Glucosinolates were not detectable in the rapeseed products.

FUNCTIONAL PROPERTIES OF NOVEL PROTEINS: ALFALFA LEAF PROTEIN

ABSTRACTFunctional properties of protein concentrates from alfalfa leaves (ALP) prepared by several methods were determined. Minimum solubilities occurred around pH 3.5–4; sodium chloride 0.05–0.2M had little effect on minimum solubility. Extraction of the lipids from ALP with acetone decreased solubility slightly; increased the bulk density (2‐3‐fold); and reduced water and fat absorption capacities by 50% compared to the controls. Both emulsifying activities and emulsion stabilities of ALP samples were generally better than those of soy protein concentrate but poorer than those of soy sodium proteinate i.e., average of 57, 48 and 87 and 60, 50 and 90%, respectively. Emulsifying capacity of ALP samples were reduced following acetone extraction.