Chemical,functional and physicochemical properties of flour from cassava stored under freezing

Cassava root spoils rapidly after harvest but can be well preserved by storing under freezing. This study investigated the functional, chemical and physicochemical properties of flour produced from frozen cassava roots. Freezing period did not significantly (p < 0.05) alter the moisture, ash, fat and fibre, but had slight effect on the carbohydrate and protein contents of the flour. Lightness, yellowness index and bulk densities of the flour samples reduced with freezing period. While freezing did not significantly (p < 0.05) change the ability of the flour samples to absorb oil, a slight but significant increase in the water absorption capacity was observed. Potassium (1.29–3.46 mg/kg), sodium (1.24–1.28 mg/kg), and calcium (0.94–1.34 mg/kg) were the major minerals in the cassava flour samples. The cyanide content (10.80–22.95 mg/kg) reduced as freezing days increased but peak, setback, breakdown and final viscosities did not follow a particular pattern. The information from this study is important to further determine the industrial potentials of flour from stored cassava roots.     

Physicochemical,nutritional and functional properties of marama bean flour

Marama bean is a protein-rich, underutilised, drought-tolerant legume in sub-Saharan Africa. Its utilisation may be increased through value addition into protein-rich flours. Defatted flour from unheated and dry-heated (150 °C/20 min) whole marama beans (UMF and HMF) were analysed for physicochemical and protein-based functional properties. Heating significantly increased in vitro protein digestibility of marama bean flour. Of functional importance are the high levels of tyrosine present in marama bean flours. Heating significantly reduced protein solubility and emulsifying capacity of marama bean flours whilst water absorption capacity was improved. Foaming capacity was not affected by heating. UMF could be useful in food systems requiring high emulsifying capacity, but would not be suitable for applications requiring high water absorption and foaming capacity. Due to its high protein contents, marama bean flour could be used to increase the protein quality of cereal-based foods to help alleviate protein-energy nutrition in the region.     

Physicochemical and functional properties of chitosans affected by sun drying time during decoloration

The typical production of chitosan from crustacean shell consists of demineralization, deproteinization, decoloration, and deacetylation. Selected physicochemical and functional properties of chitosans as affected by various decoloration times (4, 5, 6, 7 or 8 h) using sun drying were evaluated. Moisture content (6.67-6.89 g/100 g), degree of deacetylation (81.91-82.73%), and color L^∗ value (78.32-79.43) of chitosans were not affected by sun drying time. However, color a^∗ and b^∗ values decreased when sun drying time was over 4 h. The viscosity of chitosan solution (0.5 g/100 mL acetic acid) decreased gradually with increasing sun drying time, with a more pronounced effect observed at 8 h of sun drying. There was no change in water-binding capacity (WBC) of chitosans decolorized by sun drying between 4 and 6 h; however, further increase in sun drying time from 6 to 7 or 8 h increased WBC of chitosans. DPPH radical scavenging activity of chitosans increased with increasing sun drying time. This study demonstrated that white-colored chitosans could be produced by an alternative decoloration step using sun drying for 4 h following the deacetylation step. However, increasing sun drying time to 7 h produced chitosan with increased WBC and DPPH radical scavenging activity.     

Antioxidant Parkia speciosa pod powder as potential functional flour in food application: Physicochemical properties’ characterization

Chemical, physicochemical and functional properties of fibrous materials from freeze dried (FDPSP) and oven dried (ODPSP) Parkia speciosa pod (PSP) were evaluated in order to examine the potential applications in food. Preliminary screening of PSP using scanning electron microscope showed that PSP consisted of starches and fibres. Proximate analysis showed that both samples consisted of 4.3–5.2% of moisture, 9.5–10.7% of protein, 0.1–0.2% of fat, 0.01% of ash, 16.5–16.8% of crude fibre and 68.3–68.7% of carbohydrates. However, different functional properties were shown in these samples. FDPSP gave a lighter colour compared to ODPSP. Higher values of solubility (30.8%), water- and oil-holding capacities (3.72 and 1.55 g/g, respectively) were found in FDPSP. Conversely, higher emulsifying activity of 62.7% with high emulsion stability of 99.9% was shown in ODPSP. Higher antioxidative properties were also shown in FDPSP which consist TPC of 110.0 mg gallic acid equivalent/g sample and TFC of 8.5 mg pyrocatechol equivalents/g sample. These extracts (pre-diluted 50×) gave %DPPH_sc, %ABTS_sc and FRAP values of 65.3%, 77.4% and 1.9 mM FeSO₄, respectively. Therefore, it was suggested that PSP has the potential in producing functional fibres that could be imparted into the food system.     

Physicochemical and sensory properties of healthier frankfurters as affected by walnut and fat content

This study evaluates the physicochemical and sensory properties of healthier frankfurters with 25% added walnut (WF) versus low-fat frankfurters (6% pork fat) (LF) and traditional frankfurters (18% pork fat) (NF). Results reveal that cooking losses were unaffected (p ? 0.05) by the formulation of frankfurters. The addition of walnut led to higher (p < 0.05) redness and yellowness values, while colour parameters did not differ significantly between LF and NF sausages. Frankfurters with added walnut (WF) presented higher (p < 0.05) hardness and chewiness values than LF and NF frankfurters. Differences in composition were also accompanied by changes in the microstructure of the gel/emulsions. Frankfurters with added walnut presented a flavour significantly different from meat and scored lower (p < 0.05) on texture preferences. However, all frankfurters scored the same for overall acceptability.     

Effect of taro (Colocasia esculenta) flour addition on the functional and alveographic properties of wheat flour and dough

BACKGROUND: Taro is a plant widely produced in tropical areas for its underground corms. Taro corms are highly perishable owing to their high moisture content. In order to limit post‐harvest losses and improve the production and consumption, production and utilization of taro flour have been envisaged. In connection with this, the incorporation of taro flour into wheat‐based products has been reported to increase their keeping quality. Before consideration is given to taro flour as a substitute for wheat in bread manufacture, it is necessary to characterize the functionality of the composite flour and dough. The present study investigated the physicochemical and alveographic properties of wheat–taro composite flour. RESULTS: Three varieties of taro flour (WCN, RIN and KWN) were incorporated into wheat flour in proportions of 10%, 20% and 30% (w/w) and the water absorption capacity (WAC), retrogradation index (RI), foam capacity (FC) and other functional properties were measured. In addition, characteristics of dough rupture pressure (P), extensibility (L), elasticity index (Ie) and strength (W) of flour made from the different composites were measured using an alveograph. The results showed that WAC significantly increased from 132% (wheat flour) to 156% (30% composite flour), while RI significantly decreased from 38% to a mean value of 22%. Principal component analysis revealed that WAC and P formed a group of variables negatively correlated with a second group made of RI, FC, W, Ie and L. CONCLUSION: Incorporating taro flour up to a level of 10% had no significant effect on the functional and alveographic properties of the flours. This suggested that in order to guarantee the quality of bread made from wheat–taro composite the level of taro addition should not exceed 10%. Copyright © 2007 Society of Chemical Industry     

Comparative study of the functional,thermal and pasting properties of flours from different field pea (Pisum sativum L.) and pigeon pea (Cajanus cajan L.) cultivars

Physicochemical, functional, thermal and pasting properties of flours from field pea (LFP-48 and PG-3) and pigeon pea (AL-15 and AL-201) cultivars were determined and related to each other using Pearson correlation and principal component analysis (PCA). Field pea flours (FPF) were significantly (P < 0.05) different from pigeon pea flours (PPF) in their lower ash and higher fat and protein contents. FPF also exhibited higher L^∗, ΔE value, water solubility index (WSI), oil absorption capacity (OAC), foaming capacity (FC) and lower a^∗, b^∗ value, water absorption index (WAI) and water absorption capacity (WAC) in comparison to PPF. FPF differed significantly from PPF in exhibiting lower transition temperatures (T_o, T_p, T_c), enthalpy of gelatinization (ΔH_gel), peak height index (PHI) and higher gelatinization temperature range (R). PCA showed that LFP-48 and PG-3 flours were located at the far left of the score plot with a large negative score, while the AL-15 and AL-201 flours had large positive scores in the first principal component. Several significant correlations between functional, thermal and pasting properties were revealed, both by Pearson correlation and PCA. Pasting properties of the flours, measured using the rapid visco analyzer (RVA), also differed significantly. PPF were observed to have higher pasting temperature (PT), peak viscosity (PV), trough viscosity (TV), breakdown (BV), final viscosity (FV) and lower setback viscosity (SV) as compared to FPF.     

Physicochemical,nutritional and functional properties of Cucurbita moschata

Cucurbita moschata is widely planted in most parts of the world, and is rich in carotenoids, vitamins, dietary fiber, minerals, and phenolic compounds. It also has important medicinal value. Some related research has proven that Cucurbita moschata has the potential ability to induce anti-obesity, anti-diabetic, antibacterial, and anticancer effects. At the same time, it has attracted more attention in the medical field. These nutrients and bioactive compounds in Cucurbita moschata have important effects on human health. In order to make better use of this crop, it still needs further study. Therefore, the purpose of this article is to summarize the physicochemical properties and nutritional components of Cucurbita moschata, and to provide a reference for further research on the benefits of on human health.     

Physicochemical and functional properties of Caryota urens flour as compared to wheat flour

Starch digestibility, thermal, pasting and gelling properties of Caryota urens (CU) flour were investigated using wheat flour as reference. Amylose content of CU and wheat flour was 32.1% and 28.3%, respectively. CU flour had very low content of protein and lipid but had a high content of total starch (98.2%) and resistant starch (RS) [42.5%]. Gelatinisation temperature (78.5 °C) of CU flour was higher than wheat flour. Pasting behaviour of CU flour was similar to that of high swelling tuber and root and waxy starches. CU flour retrograded to a greater extent than wheat flour. Very specific gelling behaviour was noticed for CU flour where it produced significantly harder gel with high paste clarity, fracture ability, adhesiveness, gumminess and chewiness. Expected glycaemic index (eGI) of CU and wheat flour was 92.4 and 100.4, respectively. CU flour had high eGI despite high content of resistant starch.     

Diversity in properties of seed and flour of kidney bean germplasm

The genetic diversity in seeds (physicochemical, hydration, textural and cooking properties) and flours (pasting and gel texture) among kidney bean lines was studied. A wide range of variation was observed for yield and yield-related traits. Seed weight, volume, density, hydration capacity, hydration index, swelling capacity, cooking time and amylose content ranged from 10.2 to 51.7 g/100 seeds, 14 to 46 ml/100 seeds, 0.51 to 2.15 g/ml, 0.03 to 0.62 g/seed, 0.16 to 0.97, 1.24 to 1.93 ml/seed, 50 to 120 min, and 0.09% to 5.02%, respectively. Hardness, cohesiveness, gumminess, springiness and chewiness of hydrated seeds ranged from 0.81 to 2.03 g, 0.18 to 0.48, 0.20 to 0.97 g, 0.31 to 0.51 and 0.08 to 0.43 g, respectively. Pasting temperature, peak viscosity, breakdown, final viscosity and setback ranged from 79 to 95 °C, 402 to 3235 cP, 9 to 393 cP, 862 to 5311 cP, and 363 to 2488 cP, respectively. Hardness, cohesiveness, gumminess, springiness, chewiness and adhesiveness of flour gels ranged from 3.9 to 5.3 g, 0.52 to 0.76, 1.47 to 23.52 g, 0.91 to 0.99, 3.21 to 23.91 and 13.2 to 178.5 g s, respectively.     

Physicochemical and functional properties of full fat and defatted cashew kernel flours

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.     

Characterisation of sweetpotato from Papua New Guinea and Australia: Physicochemical,pasting and gelatinisation properties

The physicochemical and functional properties of flours from 25 Papua New Guinean and Australian sweetpotato cultivars were evaluated. The cultivars (white-, orange-, cream-, and purple-fleshed, and with dry matter, from 15 to 28 g/100 g), were obovate, oblong, elliptic, curved, irregular in shape, and essentially thin-cortexed (1–2 mm). Flour yield was less than 90 g/100 g solids, while starch, protein, amylose, water absorption and solubility indices, as well as total sugars, varied significantly (p < 0.05). Potassium, sodium, calcium, and phosphorus were the major minerals measured, and there were differences in the pasting properties, which showed four classes of shear-thinning and shear-thickening behaviours. Differential scanning calorimetry showed single-stage gelatinisation behaviour, with cultivar-dependent temperatures (61–84 °C) and enthalpies (12–27 J/g dry starch). Oval-, round- and angular-shaped granules were observed with a scanning electron microscope, while X-ray diffraction revealed an A-type diffraction pattern in the cultivars, with about 30% crystallinity. This study shows a wide range of sweetpotato properties, reported for the first time.     

Effect of calcium content in the corn flour on RVA profiles

Corn flour was produced using the traditional nixtamalization process and different steeping times of 0, 1, 5, 6, 10, 13, and 24 h. The flour particle size distribution was then evaluated in terms of the particles retained by using a 40 US mesh screen. The lime content, the Rapid Visco Analyzer (RVA) profiles, maximum peak viscosity, breakdown and final viscosity (V) were measured as a function of the steeping time. It was found that the initial rate of increase in viscosity (dV/dt), maximum peak viscosity, breakdown and final viscosity of fractions depended on the amount of calcium incorporated in the corn kernels during the steeping time (T_s) of the nixtamalization process. The particles retained using a 40 mesh that were steeped for 0-5 h, do not have the characteristic points of an RVA profile, i.e., maximum peak viscosity and breakdown. However, the particles retained using a 40 mesh and steeped for 6-24 h developed peak viscosity, breakdown and final viscosity. The corn flours that are recommended for making tortillas are precisely the flours whose particle size distributions develop these three characteristic points in the RVA profile. Differences in RVA measurements of the size fractions can be explained on the basis of the calcium content of the course fractions of corn flours. It was concluded that RVA characteristics may be changed by the calcium content in the starch polymer structures created during the nixtamalization process. Consequently, the increased calcium content in starch particles should be reflected in RVA measurements as an increase in the peak viscosity, in the gelatinization rate and in the development of a noticeable breakdown.     

Some properties of corn starches II: Physicochemical,gelatinization, retrogradation,pasting and gel textural properties

The physicochemical, thermal, pasting and gel textural properties of corn starches from different corn varieties (African Tall, Ageti, Early Composite, Girja, Navjot, Parbhat, Partap, Pb Sathi and Vijay) were studied. Amylose content and swelling power of corn starches ranged from 16.9% to 21.3% and 13.7 to 20.7 g/g, respectively. The enthalpy of gelatinization (ΔH_gel) and percentage of retrogradation (%R) for various corn starches ranged from 11.2 to 12.7 J/g and 37.6% to 56.5%, respectively. The range for peak viscosity among different varieties was between 804 and 1252 cP. The hardness of starch gels ranged from 21.5 to 32.3 g. African Tall and Early Composite showed higher swelling power, peak, trough, breakdown, final and setback viscosity, and lower ΔH_gel and range of gelatinization. Pearson correlations among various properties of starches were observed. Gelatinization onset temperature (T_o) was negatively correlated to peak-, breakdown-, final- and setback viscosity (r = −0.809, −0.774, −0.721 and −0.686, respectively, p < 0.01) and positively correlated to pasting temperature (r = 0.657, p < 0.01). ΔH_gel was observed to be positively correlated with T_o, peak gelatinization temperature and (T_p) and gelatinization conclusion temperature T_c (r = 0.900, 0.902 and 0.828, respectively, p < 0.01) whereas, it was negatively correlated to peak- and breakdown- (r = −0.743 and −0.733, respectively, p < 0.01), final- and setback viscosity (r = −0.623 and −0.611, respectively, p < 0.05). Amylose was positively correlated to hardness (r = 0.511, p < 0.05) and gumminess (r = 0.792, p < 0.01) of starch gels.     

Physicochemical,Morphological, Thermal and Pasting Properties of Starches Isolated from Rice Cultivars Grown in India

Physicochemical, morphological, thermal, and pasting properties of starches, isolated from basmati (HBC-19 and Bas-370) and non-basmati (Jaya, a coarse cultivar; P-44 and HKR-120, the medium cultivars and Sharbati, fine cultivar) rice cultivars grown in India were studied. The amylose content of starches from different cultivars ranged from 2.25 (Jaya) to 22.21 g/100 g of starch (HBC-19). Jaya, HKR-120, and P-44 cultivars showed soft gel consistency as 84, 73, and 69 mm, respectively, whereas Sharbati, Bas-370 and HBC-19 cultivars showed medium gel consistency as 54, 53, and 58 mm, respectively. Swelling power (at 95°C) indicated a significant positive correlation with amylopectin content (r = 0.828, p < 0.05) and gel consistency (r = 0.983, p < 0.01). Turbidity had a highly significant positive correlation with solubility (r = 0.919, p < 0.01) and amylose content (r = 0.945, p < 0.01). Starch form Jaya cultivar showed the presence of smallest size granules (2.4–5.7 μm) with an average size of 3.96 μm, whereas Bas-370 showed the presence of largest size granules (3.3–6.7 μm) with an average size of 5.0 μm. The transition temperatures, enthalpy of gelatinization (ΔH_gel), peak height index (PHI) and gelatinization range were determined using differential scanning calorimetry (DSC). The starch from Sharbati cultivar showed highest onset temperature (T_o), peak temperature (T_p), conclusion temperature (T_c), enthalpy of gelatinization and peak height index (PHI) of 68.8°C, 73.2°C, 79.0°C, 11.56 J/g and 2.63 respectively. Pasting temperature of rice starches varied from 68.9°C (Jaya) to 74.5°C (Sharbati). The peak viscosities observed were in the range of 2223 to 3297 cP, lowest for HBC-19 starch and highest for Jaya starch.     

Physicochemical and Functional Characterization of Baby Lima Bean (Phaseolus lunatus) Starch

One potential source of starch is the tropical legume baby lima bean (Phaseolus lunatus) that contains around 56—60% of starch. The objectives of this work were to evaluate this starch's physicochemical and functional properties and compare it with the properties of other starches. The chemical composition of lima bean starch was: 10.16% moisture, 0.20% protein, 0.67% fiber, 0.14% ash, 0.54% fat, 98.43% starch and 0.013% phosphorus. The amylose content was higher (32.7%) than that of other cereal and tuber starches but similar to other legume starches. The average granule size (diameter 17.9 μm) was comparable to that of corn starch and of other legume starches. The granule was heterogeneous, presenting an oval shape. The gelatinization temperature was 80.16 °C (range 75—87 °CC), which is similar to other legume starches but higher than that of corn starch. The molecular size (alkali number 3.22), was smaller than that of potato starch but similar to that of corn starch. Compared to corn starch, the gels were firmer and presented a higher degree of retrogradation even at high concentrations. The water solubility was positively correlated with the temperature: i.e., 1.8, 3.4, 8.5 and 12.3% at 60, 70, 80 and 90 °C, respectively. The swelling power had the same behaviour: 2.6, 3.3,12.8 and 19.9 g of water/per gram of starch at 60, 70, 80 and 90 °C, respectively. The amylogram showed that the viscosity (680 Brabender units) and stability were higher than those of commercial corn starch (252 Brabender units). The use of this starch in the preparation of syrups with high glucose contents, as well as in baked and canned products that require heating, is suggested.     

Physicochemical,thermal, rheological,and morphological properties of flour from different guar seed (Cyamopsis tetragonoloba) cultivars

In the present study, physicochemical, thermal, rheological, and morphological properties of flours from guar seed cultivars (G80, Ageta 112, and HG365) were assessed. Ageta 112 flours showed the highest protein content (26.78%) and varied significantly from G80 and HG365. The fiber, ash, and carbohydrate displayed significant differences in all three guar cultivars. Maximum gum content was extracted from G80 (41.19%), followed by HG365 and Ageta 112. Assessment of thermal properties revealed G80 flours with highest onset, peak, and endset temperature. Flours from cultivar Ageta 112 were recorded with highest paste temperature and peak viscosity and G80 flours showed lowest setback viscosities. Scanning electron microscopy was used to observe the morphological structure of different guar seed flour. Scanning electron micrographs presented the internal structure containing the galactomannans. Several significant correlations between physicochemical, gum yield, and thermal properties were revealed by Pearson correlation.     

Physicochemical properties and quality parameters of herbhoneys

Herbhoney is a honey-like substance produced by bees fed on a saccharose-based food supplemented with herbal extracts or fruit juices. Having specific sensory characteristics (colour, aroma and taste), different from those of natural honeys, herbhoneys greatly extend the range of bee products. With the aim of improving the knowledge of herbhoneys of various origins, their chosen physicochemical and quality parameters were evaluated. It was found that the herbhoneys studied satisfied most of the requirements relative to natural honeys (water, hydroxymethylfurfural and saccharose contents, free acidity, and diastase number). Some of the samples showed an increased specific conductivity, characteristic of honeydew honeys, although the ash contents of herbhoneys were at a level typical of nectar honeys. The saccharose content of some herbhoneys exceeded the value allowed for most natural honeys. Mineral composition varied between the samples, being in most cases within the limits reported in this literature for natural honeys.