CERTAIN FUNCTIONAL PROPERTIES OF SUNFLOWER MEAL PRODUCTS

Certain functional properties including water absorption, fat absorption, emulsification, whippability and foam stability were determined on the sunflower flour, protein concentrates and isolate. The results were also compared to those obtained on soy products. Data on water and fat absorption studies suggest that soy products are more hydrophilic in nature while sunflower material exhibited greater lipophilic properties than the soy products. Emulsification tests showed that sunflower flour was superior to all other soy and sunflower products. In general, whipping properties of soy and sunflower isolates were similar, while less whippability was observed for the soy flour and protein concentrates. Whipped foams produced by soy and sunflower protein isolates and sunflower flour were more stable than soy flour, soy and sunflower protein concentrates.     

Effects of Acylation of Defatted Cottonseed Flour with Various Acid Anhydrides on Protein Extractability and Functional Properties of Resulting Protein Isolates

Maleylation, succinylation, dimethylglutarylation, and sodium sulfite treatment of cottonseed flour increased protein extraction from the flour in suspension, and precipitated more protein in the extract at pH 4.0, compared to unmodified flour processed through conventional methods. However, acetylation decreased protein extraction and precipitation at this pH. Protein isolates from succinylated, maleylated and dimethylglutarylated flours were highly water-soluble, and did not coagulate by heating. Acetylation decreased heat coagulability of the resulting protein isolate, but did not affect water solubility of the isolate. Treatment of the flour with sodium sulfite markedly increased heat coagulability of the isolate, and decreased its solubility. Oil absorption capacity of the isolate was increased slightly by dimethylglutarylation, but other treatments did not affect the capacity significantly. Sensitivity of proteins in isolates to calcium ions was not affected by acylation or sodium sulfite treatment of the flour.     

Rheology Models for Pseudoplastic Soy Systems Based on Water Binding

The objectives were to (1) determine the effects of sucrose, glucose, sodium chloride and soy soluble carbohydrate on flow characteristics of suspensions of polymers, and (2) investigate the relationship between these effects and the quantity of water associated with polymer and solute in the suspension. Polymers were defatted soy flour, soybean sodium proteinate and soybean cell wall material. A strong linear relationship was developed between the ratio of polymer and polymer bound water to solute and solute bound water (P/S) and flow characteristics. The models developed from these relationships held for soy flours containing both polymer and solute. Suspensions with high P/S showed a high degree of pseudoplastic behavior.     

In situ examination of starch granule-soy protein and wheat protein interactions

The objective of this study was to evaluate the association between heat and pressure-treated soy proteins and wheat prime starch relative to the level of granule surface proteins present. Soy isolates were manufactured from defatted soy flour and from two types of textured soy flour. Conditions for binding between wheat starch and soy fractions were established by altering pH, protein and sucrose concentrations. Conformations of exogenous proteins bound to the wheat starch granule surface were evaluated using an amyloglucosidase assay. Proteins present on the granule surface were removed and soy protein binding was reevaluated. Thermal and pressure processing of soy protein significantly influenced binding kinetics. Textured soy proteins exhibited increased wheat starch granule adsorption characteristics compared to untreated soy protein. Removal of native wheat starch granule surface proteins decreased the binding of added proteins. This suggests that native granule proteins may mediate the binding of exogenous protein.     

Investigation of Faba Bean Protein Recovery and Application to Pilot Scale Processing

Extraction and precipitation conditions were assessed for recovery of protein from dehulled faba bean flour on a laboratory scale. 10°C versus 20°C extraction did not affect solubility of nitrogenous components. However, more were extracted at pH 9 or 10 than at pH 7. Tap water extracted slightly more nitrogenous materials than 0.3M sodium chloride. Study of pH 4.0 to 5.3 for protein precipitation showed a higher yield of protein was obtained at lower pH. However, apparently simultaneous precipitation of nonproteinaceous material caused overall lower protein composition of the isolates from lower pH. Pilot scale processing of dehulled faba bean flour produced an isolate which was 92.5% protein, and represented a yield of 48% of the original protein.     

青稞全粉与中筋小麦粉复配体系品质特性研究

选用青稞全粉作为研究对象,与中筋小麦粉复配,检测不同添加量青稞全粉的损伤淀粉特性、粉质特性、糊化特性、溶剂保持力,并进行相关性分析。研究表明:随着青稞全粉比例增加,破损淀粉显著增加(P<0.05),且与降落数值呈显著负相关;面团的吸水率呈上升趋势,当青稞全粉添加量为85%时面团的吸水率达到最大值73.10%,吸水率、弱化度显著增加(P<0.05);不同添加量对混合粉稳定时间的影响不显著;峰值黏度、最低黏度、最终黏度、衰减值、回生值显著下降(P<0.05),降落数值与峰值黏度呈极显著正相关;乳酸溶剂保持力SRC显著减少(P<0.05),湿面筋含量和乳酸溶剂保持力SRC呈极显著正相关;碳酸钠溶剂保持力SRC、蔗糖溶剂保持力SRC、水溶剂保持力SRC显著增加(P<0.05),破损淀粉值与碳酸钠溶剂保持力SRC,蔗糖溶剂保持力SRC与吸水率、蛋白质,水溶剂保持力SRC与蛋白质均呈极显著正相关性。     

Differential Scanning Calorimetry Analysis of the Effects of Heat and Pressure on Protein Denaturation in Soy Flour Mixed with Various Types of Plasticizers

The effects of heat and pressure on protein denaturation in soy flour were explored by an experimental design that used pressure (atmospheric to 600 MPa), temperature (room to 90 °C), time (1 to 60 min), and type of aqueous plasticizer (NaCl, sucrose, betaine, and lactobionic acid (LBA)) as factors. When 50% (w/w) soy flour‐water paste was high hydrostatic pressure (HHP)‐treated for 20 min at 25 °C, the treatment at 200 MPa showed a small effect on denaturation of only the 7S soy globulin, but the treatment at 600 MPa showed a significant effect on denaturation of both the 7S and 11S soy globulins. The treatment at 60 °C showed a less‐pronounced effect on denaturation of the 11S globulin, even at 600 MPa, but that at 90 °C showed a similar extent of denaturation of the 11S globulin at 600 MPa to that at 25 °C. Chaotropic 2N NaCl, 50% sucrose‐, 50% betaine‐, or 50% LBA‐water solutions showed protective effects on protein denaturation during HHP treatment at 25 °C. Although LBA enhanced the extent of thermostability of soy protein less than did 2N NaCl, LBA exhibited better stabilization against pressure. The results from DSC analysis demonstrated that thermostable soy proteins were not always barostable.     

Extractability and functional properties of some legume proteins isolated by three different methods

The extraction of protein from the flour of three grain legumes (faba beans, chick peas and fenugreek) was investigated using three different methods. Three protein preparations were made: by alkaline extraction and precipitation at isoelectric pH (protein isoelectric precipitate, PIP); extraction with 0.5 M sodium chloride solution and precipitation by ionic strength reduction (protein micellar mass, PMM); extraction in aqueous or saline solution in the presence of pepsin or pancreatin (partially hydrolysed protein preparation, PHP). Two of the protein isolates had higher values of water absorption and fat absorption compared to their corresponding parent flours, with fenugreek being the exception. Oil emulsification of the isolates was in the descending order: PMM, PHP and PIP. The PHP isolate had the highest nitrogen solubility index (NSI) values at pH 2.4 followed by PMM at pH 5.7–6.4 and finally PIP at pH 4.5–5.5.     

Effect of lipoxygenase activity in defatted soybean flour on the gelling properties of soybean protein isolate

Soybean lipoxygenase was inactivated to different degrees by dry heating of defatted soybean flour for 0, 5, 10, 15, 20 and 25 min and soy protein isolates were prepared thereof by isoelectric precipitation of the water extract of the defatted soybean flour. The fluorescence emission intensity at 420 nm of the chloroform–methanol extract of soy protein isolates, which was indicator of the existence of peroxidized lipid, varied in parallel with the lipoxygenase residual activity in defatted soybean flours. The dispersion of soy protein isolate showed an increasing turbidity with the increase of lipoxygenase residual activity in the starting defatted soybean flour, suggesting an elevated tendency to form insoluble aggregates during the preparation of soy protein isolate. Small deformation rheological test revealed that the gelling times were shorter for those soy protein isolates derived from low lipoxygenase activity defatted soybean flours than that of high lipoxygenase activity. Frequency sweep showed that G′ of soy protein isolate derived from low lipoxygenase defatted soybean flour was independent of oscillation frequency in contrast to that of derived from non dry-heated defatted soybean flour, the latter showed a marked frequency dependence. Large deformation test revealed that the gel hardness increased about 10 times after dry heating of defatted soybean flour for 20 min. As the increase of the lipoxygenase residual activity, the gel permeability increased markedly, suggesting that soy protein isolate from high lipoxygenase defatted soybean flour produced coarser textured gel, which corresponded well with the results of scanning electron microscopy.     

Development of a Food Mixture for Infants and Young Children in Brazil

SUMMARY-The development of food mixtures containing vegetable protein concentrates, minerals, and vitamins represents an important approach to the problem of protein-calorie malnutrition of preschool children in many parts of the world. In Brazil, soy flour is the most readily available good-quality protein for this purpose. Protein efficiency-ratio studies in rats demonstrated that soy flour with a PER value of 1.99 was available in large quantities. Accordingly, a formula containing 19.50% soy flour, 4.50% nonfat milk powder, 32.28% corn starch, 39.00% sucrose, and 4.72% vitamins and minerals was thoroughly tested as an infant food. The PER value of the protein in rats was 2.31. Amino acid assay demonstrated that the protein compared favorably with the essential amino acid pattern of the FAO/WHO reference protein (FAO/WHO, 196.5) except for methionine-cystine, The formula was well accepted and tolerated by children and adults. Average nitrogen absorption and retention of the formula as the sole food of malnourished children were 72.68 and 23.82%; values for milk protein were 80.17 and 30.13%. Average nitrogen absorption and retention were 63.4 and 22.0% when the formula provided one-half (15 g) of the daily protein for normal children consuming a typical diet of the region, comparing favorably with values of 69.3 and 21.3% for milk protein.     

不同大豆蛋白对小麦面条加工品质和血糖生成指数的影响

为改善小麦面条品质,在小麦粉中添加大豆蛋白(全脂豆粉、脱脂豆粉、大豆分离蛋白、大豆浓缩蛋白、大豆组织蛋白),以拉伸特性、蒸煮特性、微观结构以及血糖生成指数为评价指标,研究大豆蛋白添加量(0%、5%、10%、15%、20%)对面条加工品质及血糖生成指数的影响。结果表明:随蛋白添加量的增加,脱脂豆粉、全脂豆粉的增加使面条的拉断力呈明显上升趋势,拉伸距离呈先上升后下降趋势,大豆分离蛋白、大豆浓缩蛋白添加量的增加使拉断力呈先上升后下降趋势,拉伸距离呈下降趋势,而大豆组织蛋白的增加使面条拉伸性能均逐渐降低;当大豆蛋白添加量为10%时,混合粉面条拉伸特性较优;五种大豆蛋白的添加均使面条的烹煮损失率及断条率上升,全脂豆粉的增加使面条的吸水率、膨胀率逐渐下降,其余四种均使其上升;微观结构表明,脱脂豆粉和全脂豆粉的添加使混合粉面条的面筋网络结构更加连续均匀,而其余三种大豆蛋白添加量的增加造成混合粉面条微观结构的劣变;利用体外复合酶方法测定GI值,血糖生成指数依次为:小麦粉 > 脱脂豆粉 > 全脂豆粉 > 大豆组织蛋白 > 大豆浓缩蛋白 > 大豆分离蛋白。     

主要几种配料对挤压膨化早餐谷物挤压特性的影响

采用双螺杆连续挤压机生产早餐谷物食品的经典工艺，选用大米为挤压基料，探讨了糖、油脂、蛋白质、膳食纤维及品质改良剂等配料对谷物挤压特性的影响。研究结果表明：1％-5％还原糖即可使产品组织结构变得均匀细密、产品色泽加深、风味加强、膨化度和水溶性指数加大、吸水指数变化不大；加入蔗糖在8％以上时，即可抑制挤压谷物产品的膨化度，提高产品脆度，降低其吸水指数，对产品水溶性指数影响不大。加入少量的油脂、大豆蛋白和膳食纤维可改善产品的感官指标，提高产品营养；大豆磷脂和碳酸钙可作为挤压谷物产品品质改良剂。     

Production and Evaluation of Pea Protein Isolate

Laboratory and pilot plant processes were developed for producing pea protein isolate from field peas. Sodium proteinate and isoelectric products containing up to 90% protein were obtained by alkaline extraction and precipitation at the isoelectric point. Drying was carried out by freeze, spray and drum processes. Chemical analysis, functional properties, color and flavor of the dried isolates compared favorably with their soy counterparts. Generally, the sodium proteinates exhibited more functionality than isoelectric isolates. Drum drying decreased the nitrogen solubility index and increased water absorption. Freeze- and spray-drying resulted in isolates with the highest emulsification and water absorption values. Spray drying produced the best foaming, color and flavor properties.     

Formulation and Processing of a Heat Stable Calcium-fortified Soy Milk

Calcium-fortified soy milk (200 mg/100g) was formulated by adding water (85–90°C) full-fat soy flour (10%), sucrose (2.75%) and soy protein isolate (2.25%). Following homogenization, the blend was twice clarified and pasteurized at 65°C/30 min before refrigeration. Samples of the soy milk (45°C) were adjusted to pH 8 before adding calcium lactogluconate (1.55%) and varying amounts of sodium hexametaphosphate or potassium citrate. Samples with 1.25% potassium citrate the best heat stability. For successful calcium fortification, it is recommended to maintain a calcium-to-protein ratio < 38 mg/g and to use an appropriate sequestering agent at a molar ratio of 0.8/mole calcium.     

Physicochemical and functional properties of flour and protein isolates extracted from seinat (Cucumis melo var. tibish) seeds

The physicochemical and functional properties of seinat seed flour (SSF), defatted seinat flour (DSSF), and protein isolates were studied. Protein was extracted from DSSF using an alkali solution with isoelectric precipitation and freeze drying. Freeze dried seinat seed protein isolates (FSSPI), SSF, and DSSF were evaluated for their physicochemical and functional properties. SSF contained high levels of crude fat and fiber (31.13% and 24.75%, respectively). FSSPI contained 91.83% protein versus 28.58% for SSF. The amounts of potassium, the mineral with the highest content, were 9,548.33, 6,439.03, and 1,029 mg/100 g in SSF, DSSF, and FSSPI, respectively. The functional properties were variable among samples. The protein solubility of FSSPI was significantly higher (p<0.05) than for DSSF and SSF. FSSPI has a significantly better (p<0.05) foaming capacity, water/fat absorption capacity, and bulk density than SSF and DSSF. FSSPI also showed an emulsifying capacity comparable to commercial soy protein isolates.     

Purification and identification of interacting components in a wheat starch–soy protein system

The objective of this research was to quantify the solubility, hydrophobicity and interaction characteristics of wheat–starch proteins (puroindoline, gliadin and glutenin) and protein-containing soy fractions (soy flour isolate [SFI], SFI 7S and 11S fractions, hexane-extracted textured soy flour [TVP] isolate, TVP 7S and 11S fractions, expelled, extruded soy flour [TSP] isolate, TSP 7S and11S fractions). Functional characteristics were assessed in aqueous sucrose solutions at pH 5.5 and 7.5 after heating to 25, 50, and 100 °C. Textured soy protein fractions were more soluble and had higher surface hydrophobicity profiles than their untextured counterparts. Sucrose addition decreased hydrophobicity in the textured proteins but increased it in untextured proteins. Characteristics of the isolate, as a whole, appear to be dictated by those of its 11S moiety. Dissociation constants (K_d values) for soy protein and starch-derived puroindoline were determined and indicated an extremely short association in all cases. The 11S fractions formed a complex with puroindoline in solution; however 7S fractions did not.     

Utilization of Transglutaminase to Increase the Level of Barley and Soy Flour Incorporation in Wheat Flour Breads

ABSTRACT: This study investigated the possibility of incorporating barley or soy flour into wheat flour using transglutaminase (TG)-catalyzed cross-linking, without deterioration in bread quality. A Farinograph and texture analyzer were used to examine mixing properties and extensibility of doughs, respectively. Addition of increasing levels of barley/soy flour (with and without TG) increased Farinograph water absorption in the soft and hard wheat cultivars studied. Dough resistance increased and extensibility decreased with TG treatment. TG showed great promise in processing of bread supplemented with barley flour, even at a very low level (0.25%, wt/ wt), but did not notably improve the quality of soy flour-supplemented breads.     

脱脂豆粕的加工和利用

着重介绍了食用脱脂豆粕的加工现状,并阐述了由脱脂豆粕生产的大豆蛋白制品（脱脂豆粉,大豆分离蛋白等）在食品中的广泛应用。     

Nutritional Improvement of Soy Flour Through Inactivation of Trypsin Inhibitors by Sodium Sulfite

Treatment of raw soy flour at 75°C with 0.03M sodium sulfite for 1 hr completely inactivated trypsin inhibitors leaving no sulfite residues in the soy proteins. Rat feeding studies showed that the protein efficiency ratio (PER) increased from 1.55 for raw flour to 2.11 for heated flour and 2.49 for flour heated in the presence of sulfite. This nutritional improvement was accompanied by enhancement in in vivo nitrogen digestibilities. Pancreas weights were elevated in rats fed raw soy flour, but not in those consuming heated soy flour, with or without sodium sulfite. Knowledge of the factors that decrease the stability of potentially toxic trypsin inhibitors may be useful for improving the quality of certain foods.     

Properties of some citrus seeds. Part 2. Functional properties of seed flours

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.