Functional Properties of Extruded Rice Flours

The functional properties of a long‐grain and a short‐grain rice flour extruded at 70 to 120°C and 22% moisture are reported. The bulk densities essentially stayed unchanged. Both water absorption and water solubility indices increased with an increase in extrusion temperature. The fat absorption indices decreased only at 55°C. The cold‐paste viscosities progressively increased, whereas the peak, breakdown, setback, and final viscosities decreased with an increase in extrusion temperature. A substitution of 25% of unextruded or 70°C extruded long‐grain rice flour into a wheat flour‐based fried snack decreased its fat absorption by 35% to 50% without affecting the overall texture.     

脱皮脱脂杂豆粉的理化与功能特性

以大白芸豆、奶花芸豆、小白芸豆、豇豆、绿豆、红小豆、小扁豆、豌豆8种食用杂豆为实验材料,以大豆为对照,对其脱皮、脱脂后的杂豆粉理化特性和功能特性进行比较分析。结果表明：与脱皮脱脂大豆粉相比,脱皮脱脂杂豆粉的堆积密度和吸水性指数高,水溶性指数、吸水能力、吸油能力低,乳化性、乳化稳定性差异不显著,凝胶能力强,起泡性及起泡稳定性差异显著。不同杂豆粉之间的理化特性与功能特性有差异。脱脂大白芸豆粉的堆积密度小,水溶性指数、吸油性和乳化稳定性高;脱脂小白芸豆粉吸水性、乳化性、起泡性及起泡稳定性强;脱脂豌豆粉凝胶能力和起泡性好,乳化稳定性差。     

Physicochemical and Functional Properties of Sour Starches from Different Cassava Varieties

This article reports our investigation on the effect of cassava varieties on the physicochemical and functional properties of sour starches. There were significant differences (P < 0.05) in the ash, pH, amylose, amylopectin, starch damage, total titratable acidity (TTA), sugar, and starch content but not moisture contents of various cassava sour starches. There were no significant differences (P > 0.05) in Water Absorption Capacity (WAC), swelling power, and solubility index, while significant differences were recorded in Least Gelation Concentration (LGC) and color at 5% level and granule size at P < 0.0001 for cassava sour starches. Peak viscosity values ranged from 333.17RVU (clone 4(2) 1425) to 380.75RVU (clone TME 1). There were significant differences (P < 0.05) in pasting properties except for pasting temperature and breakdown.     

Physical,Functional, and Sensory Characteristics of Cereal Extrudates

Eleven cereals were processed in a twin-screw extruder to produce directly expanded extrudates. Physical and functional properties (gelatinization degree, bulk density, expansion ratio, water absorption index, water solubility index, and sensory characteristics (hardness, crispness, and bowl life) of cereal extrudates were determined. Relationships among different variables were analyzed by SPSS. Gelatinization degree positively and negatively correlated to starch and protein, respectively (p ≤ 0.01). The same relationship was observed with water absorption index at the same significance level. Water solubility index positively correlated to protein (p ≤ 0.05), negatively correlated to starch (p ≤ 0.01), amylose (p ≤ 0.01), and fat (p ≤ 0.05). Density and bowl life positively correlated to fat (p ≤ 0.01) and amylose (p ≤ 0.05), respectively. Gelatinization degree had a high correlation with water solubility index (p ≤ 0.05). As gelatinization degree increased, water solubility index decreased. Crispness positively correlated to bowl life (p ≤ 0.01).     

Processing Technology Comparison of Physicochemical and Functional Properties of Cassava Starch Extracted from Fresh Root and Dry Chips

Starch was extracted from dry chips of three varieties of cassava using wet milling and dry milling methods. The physicochemical and functional properties were compared with those from fresh root. The starch obtained exhibited lower peak viscosities, breakdowns and setbacks, and higher pasting and peak temperatures than that from fresh root. Most thermal properties (onset and peak temperatures of gelatinization and retrogradation; conclusion temperatures, enthalpies and peak height indices of retrogradation; and degree of retrogradation) were found to be higher than those of fresh‐root starch. Moreover, swelling power, paste clarity and freeze‐thaw stability of the former were inferior to those of the latter. Both types of starches exhibited increased rate of syneresis with increase in freeze‐thaw cycles. Differences observed in properties of starches derived from dry chips by wet and dry millings were very minimal. No indication of major change in granule structure was noted for dry‐chip starch that would alter the properties relative to fresh root starch. Higher fiber content and annealing due to exposure to heat and moisture of the former accounted for most of the variations of properties as compared to the latter. With the advanced technology used in starch manufacturing industry today it would be possible to obtain starch from dry chips with similar quality from fresh root. This would enable the industry to overcome the cycle of glut and low season, and allow them to remain open for longer period of time in a year.     

Physical and Functional Properties of Arrowroot Starch Extrudates

ABSTRACT:  Arrowroot starch, a commercially underexploited tuber starch but having potential digestive and medicinal properties, has been subjected to extrusion cooking using a single screw food extruder. Different levels of feed moisture (12%, 14%, and 16%) and extrusion temperatures (140, 150, 160, 170, 180, and 190 °C) were used for extrusion. The physical properties—bulk density, true density, porosity, and expansion ratio; functional properties such as water absorption index, water solubility index, oil absorption index, pasting, rheological, and textural properties; and in vitro enzyme digestibility of the extrudates were determined. The expansion ratio of the extrudates ranged from 3.22 to 6.09. The water absorption index (6.52 to 8.85 g gel/g dry sample), water solubility index (15.92% to 41.31%), and oil absorption index (0.50 to 1.70 g/g) were higher for the extrudates in comparison to native starch (1.81 g gel/g dry sample, 1.16% and 0.60 g/g, respectively). The rheological properties, storage modulus, and loss modulus of the gelatinized powdered extrudates were significantly lower ( P < 0.05) and these behaved like solutions rather than a paste or a gel. Hardness and toughness were more for the samples extruded at higher feed moisture and lower extrusion temperature, whereas snap force and energy were higher at lower feed moisture and temperature. There was a significant decrease in the percentage digestibility of arrowroot starch (30.07% after 30 min of incubation with the enzyme) after extrusion (25.27% to 30.56%). Extrusion cooking of arrowroot starch resulted in products with very good expansion, color, and lower digestibility, which can be exploited for its potential use as a snack food.     

Effect of Dry Cassava Chip Storage on Yield and Functional Properties of Extracted Starch

Dry cassava chips of variety CMR35‐22‐196 and KU50 were stored at 5 and 30°C up to a period of 8 months. The yield and functional properties of the starches extracted from the chips after 2 months of storage were compared with those of starches extracted from fresh roots and freshly dried chips. Starch yield from dry chips was reduced by up to 5% after 8 months of storage. Functional properties of the starches exhibited a declining trend with increasing storage period of the chips. Peak viscosity and swelling power decreased by up to 30% and 5 g/g, respectively. Paste clarity dropped by up to 30% and syneresis of the gels increased by up to 10% after 8 months storage. A high storage temperature (30°C) was found to increase the changes in functional properties of the starches. The changes in the functional properties, however, were not so severe to negatively affect the application of the dry‐chip starches. All the properties remained within the generally recognized ranges of cassava starches. The use of dry chips for extraction of starch could thus overcome the problems of seasonal glut and closure of factories in low season.     

Processing Factors Affecting the Yield and Physicochemical Properties of Starch from Cassava Chips and Flour

Three processing factors, namely, raw materials type (RMT) (i.e. chips and flour) and raw material drying mode (RDM) (i.e. sun‐ and oven‐drying at 55 °C) were related to the yield and some physicochemical properties of starch in a 2³ factorial experiment. The quality characteristics investigated were: moisture content, pH, crude fiber content, peak viscosity and pasting temperature. Starch yields from oven‐dried chips and flour were significantly higher (at 5%) than from sun‐dried materials. The optimal yield of 55.9 g (per 70 g of dried product or 79.9%) was obtained from oven‐dried starch extracted from oven‐dried flour. The peak viscosities (PV) of starches extracted from flour and chips were similar while the observed pasting temperatures of flour‐extracted starches were not significantly different from those derived from chips.     

Comparative Study on Functional,Rheological, Thermal,and Morphological Properties of Native and Modified Cereal Flours

Effect of extrusion on the functional, rheological, thermal, and morphological properties of the modified cereal flours from different cereals was assessed. Rice flour, wheat flour, and flour, in combination (rice: wheat, 50:50) were passed through twin screw extruder to obtain modified cereal flours at variable conditions (barrel temperature: 175 and 190°C, feed moisture: 14 and 16% and screw speed: 500 rpm). Functional properties (water absorption index, water solubility index, swelling index, and viscosity) improved in modified cereal flours as compared to the unmodified flours. Modified flours showed lower paste viscosity as compared to unmodified flours, which was a desirable property for modified flours to be utilized as a functionality ingredient in food products. Processed flours recorded higher onset (T_o), peak (T_p), and endset (T_e) temperature and showed higher enthalpy change (?H) than the raw cereal flours. Degree of gelatinization was higher in flours processed at higher barrel temperature and feed moisture. The morphological pattern of modified flours was determined by scanning electron microscopy. The starch surface of cereal flours (modified and unmodified) differed from each other with respect to their morphological pattern.     

稻米-高筋小麦混合粉面团的静态和动态流变学特性

本实验研究了6 种稻米-高筋混合粉面团的静态和动态流变学特性。结果表明,随着稻米粉添加量的增加,在动态流变频率扫描中,混合面团的储存模量（G’）和损耗模量（G’’）整体呈上升趋势,损耗角正切（tan δ）整体呈规律性下降趋势;在静态流变的蠕变松弛实验中,最大蠕变应变量、最大蠕变柔量和瞬时恢复柔量逐渐减小,零剪切黏度和瞬间恢复比率逐渐增加,表明加入稻米粉后面筋蛋白有所稀释,但稻米粉中的淀粉吸水膨胀相互黏附,且与米蛋白相互作用赋予面团更高的弹性模量和更复杂的内部结构。在动态流变的温度扫描中,糊化温度前后混合面团的黏弹性变化明显,G’和G’’曲线类似淀粉糊化曲线,说明生面团加热的过程中,影响其流变学特性的主要成分为淀粉;降温过程中,稻米粉添加量的影响较小,高温区G’和G’’呈规律性增加,温度低于60 ℃后各项流变指标规律性差;在整个降温的过程中样品均具有类固体的性质。     

Cassava Fermentation and Associated Changes in Physicochemical and Functional Properties

Fermentation of cassava is an important processing technique followed in different parts of the world. Although fermentation is known to bring about vast changes in the physicochemical and functional properties of the tubers, attempts have seldom been made to consolidate and critically analyze the available information. Glaring inconsistencies and contradictions noticeable in some of the results reflect the differences and variations in the artisanal processes followed in the preparation of these products. It also stresses the need for a systematic study of not only the quoted products, but also a number of other fermented cassava products that have not been well documented.     

Nutritional Composition and Health Related Functional Properties of Eleusine coracana (Finger Millet)

Nutritional composition, antioxidant activity, alpha amylase inhibitory activity and fermentation ability of Rawana and Oshada FM varieties were measured against Basmati and BG-300 rice varieties. The results showed that both soluble and insoluble dietary fiber (DF) contents were higher (P<0.05) in Rawana and Oshada than Basmati and BG-300. Moreover, soluble and insoluble DF contents of Oshada were higher (P<0.05) than Rawana. Total flavonoid content (TFC) of Rawana was similar to Basmati and BG-300. However, Oshada had the highest TFC. Total phenolic contents (TPC) of both FM varieties were higher (P<0.05) than both rice varieties. Oshada had a higher (P<0.05) TPC than Rawana. Both FM varieties showed a higher (P<0.05) 2, 2-diphenyl-1-picrylhydrazyl (DPPH) scavengingactivity than BG-300 and Basmati. Similarly, 2, 2’-azino-bis-3-ethylbenzothiazoline-6-sulphonic acid(ABTS) scavenging activity was higher (P<0.05) in both FM varieties than Basmati and BG-300. Furthermore, ABTS scavenging activity was higher (P<0.05) in Oshada than Rawana. Alpha amylase inhibitory activity of Rawana and Oshada were higher (P<0.05) than Basmati and BG-300. However, the IC₅₀ values of both FM varieties were greater (P<0.05) than acarbose which is a drug used to treat type II diabetes. The results of the microbial fermentation study revealed that Rawana and Oshada produced a higher amount of hydrogen and carbon dioxide than rice varieties during the incubation at 39 °C with unadapted caecal microflora. Therefore, these results indicate that both FM varieties, particularly Oshada variety has more beneficial nutritional and health related protective effects than Basmati and BG-300 rice varieties in vitro.     

栗粉的理化与功能特性研究注

本文研究了以毛板红品种为原料加工成的生栗粉和熟栗粉的理化性质与功能特性,并同市售小麦面粉进行了功能特性与营养成分的比较.结果表明,在化学成分方面,熟粉有较多的淀粉发生水解,且直链淀粉含量较生粉高;功能特性方面,熟粉的吸水能力较生粉好,但吸油能力、起泡能力和泡沫稳定性较生粉差;糊化特性方面,熟粉已有部分淀粉发生糊化,各项糊化特征值都较生粉低;生粉在色泽上要比熟粉白.栗粉的脂肪和可溶性糖含量高于小麦面粉,淀粉、直链淀粉和蛋白质含量接近于面粉;栗粉的吸水能力要高于面粉,吸油能力与面粉相似,但起泡能力不及面粉.     

百合(Liliumbrownii)粉的物化性质及功能特性的研究

研究了百合粉的化学、物理和功能特性。结果表明 ,百合粉主要由淀粉和少量蛋白质组成 ,含硫氨基酸在百合磷茎含量很少 ,单糖组成主要是葡萄糖。对百合粉的功能特性如吸水性、吸油性、乳化性和起泡性等的研究表明 ,其可用于一些食品的加工。从百合粉中分离出的多糖的相对分子质量在 2 91× 10 2 ～ 1 0 2× 10 6之间。     

脱色猪血红蛋白酶解产物品质及营养特性研究

研究了脱色猪血红蛋白酶解产物的功能性、风味和营养特性。在pH3.0～9.0,产物具有良好的溶解性;在pH值为7.0左右时,显示出良好的乳化性和乳化稳定性;深度酶解和脱色导致产物的持油性较差。脱色酶解产物没有苦味,其疏水值与Q准则相互吻合。酶解和脱色可以提高猪血红蛋白的营养特性。脱色猪血红蛋白酶解产物可作为食品原料加以利用。     

Functional, Nutritional, and Rheological Properties of Protein Powders from Arrowtooth Flounder and their Application in Mayonnaise

ABSTRACT: Arrowtooth flounder soluble protein powder (AFSP) and arrowtooth flounder insoluble protein powder (AFISP) were evaluated for their functional, nutritional, and rheological properties. AFSP and AFISP contained 80% and 79% protein and 5.9% and 14.9% fat, respectively. Yield of AFSP (8.6%) was less than AFISP (13.1%). AFSP and AFISP had desirable essential amino acid and mineral contents. Emulsion stability of AFSP was greater than AFISP. Fat and water absorptions (mL/g protein) were 5.2 and 1.8 for AFSP, respectively, and 3.3 and 4.2 for AFISP Mayonnaises made from AFSP had greater emulsion stability than mayonnaise made from AFISP. Mayonnaises from both AFSP and AFISP possessed pseudoplastic and viscoelastic characteristics.     

Gluten-Free Bread Making Trials from Cassava (Manihot Esculenta Crantz) Flour and Sensory Evaluation of the Final Product

The aim of this work was to evaluate the effectiveness of the use of cassava flour in bread making, and the sensory acceptability of the final product. Different baking trials were carried out by using egg white and extra-virgin olive oil, in consideration of their high nutritional value with respect to other food additives (i.e., hydrocolloids). Significant (p < 0.05) improvements of loaf specific volume (from 2.24 to 3.93 mL/g) and crumb firmness (from 9.14 to 4.67 N) were achieved by contemporarily including egg white and extra-virgin olive oil in the formulation. Cassava breads containing both these ingredients obtained the best scores from panelists for all the test breads examined and resulted attractive as the wheat bread prepared as reference.     

Some Physical and Chemical Properties of Starch Isolates of Cassava Genotypes

Cassava starches (Manihot esculenta Crantz) were prepared from tubers of Kaesetsart 50 (KU50), Rayong 5, Hanatee and KMUL 36‐YOO2 (YOO2) and their physicochemical properties studied using the Rapid Visco Analyser (RVA), differential scanning calorimetry (DSC) and rheometry. Amylose content was determined by iodine potentiometric titration (IPT) and gel permeation chromatography (GPC). Starch contents of the tubers varied from 34.2 to 35.1% and protein and fiber contents in the starches varied from 0.8 to 1.1% and 0.6 to 0.8%, respectively. The cassava starches contained 0.06–0.12% lipid and 0.7% to 0.9% ash. Amylose content determined by IPT (15.9 to 22.4%) had higher positive correlation with peak viscosity, breakdown and gel consistencies (R₂ = 0.835, 0.772, 0.859), respectively, whereas GPC (18.1 to 25.3%) showed high correlation with setback (R₂ = 0.923) and ΔH (R₂ = 0.579). The onset gelatinization temperatures varied from 59.7–64.4°C, and KU50 exhibited highest ΔH of 13.7 J/g. Hanatee and YOO2 formed clear gels with higher peak viscosities, setback and gel consistency viscosities attributed to their higher amylose contents. Retrogradation of KU50 and Rayong 5 tended to be more severe on cooling and formed opaque gels, showing higher resistance to shearing, properties attributed to recrystallized amylopectin fractions.     

Selected Physical Properties of Expanded Extrudates from the Blends of Hazelnut Flour-Durum Clear Flour-Rice

Blends of durum clear flour, partially defatted hazelnut flour (PDHF) and rice grit were extruded through a single-screw extruder to form expanded products. The extrudates were analyzed for physical properties, namely radial expansion ratio, colour, and instrumental texture. The radial expansion ratios measured for all the extruded samples ranged between 3–4.5. Breaking strengths of the extrudates varied between 0.387–0.854 N mm^?2. The measured values of the colour parameters of extruded blends varied in the range from 48.72–72.24 for lightness (L), 1.95–5.79 for redness (a), and 13.79–15.26 for yellowness (b).