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,Thermal, Morphological and Pasting Properties of Starches from some Indian Black Gram (Phaseolus mungo L.) Cultivars

The starches separated from thirteen different black gram cultivars were investigated for physicochemical, thermal, morphological and pasting properties. Amylose content, swelling power, solubility and water binding capacity of starches ranged between 30.2–34.6%, 16.0–22.3 g/g, 14.8–17.3% and 73.5–84.5%, respectively. The diameter of starch granules, measured using a laser‐light scattering particle‐size analyzer, varied from 12.8 to 14.3 μm in all black gram starches. The shape of starch granules varied from oval to elliptical. The transition temperatures (T_o, T_p and T_c) and enthalpy of gelatinization (ΔH_gel) determined using differential scanning calorimetry, ranged between 66.1–71.3, 71.0–76.2, 75.9–80.4°C and 6.7–9.4 J/g, respectively. Pasting properties of starches measured using the Rapid Visco Analyser (RVA) also differed significantly. Pasting temperature, peak viscosity, trough, breakdown, final viscosity and setback were between 75.8–80.3°C, 422–514, 180–311, 134–212, 400–439 and 102–151 Rapid Visco Units (RVU), respectively. Turbidity values of gelatinized starch pastes increased during refrigerated storage. The relationships between different properties were also determined using Pearson correlation coefficients. Amylose content showed a positive correlation with swelling power, turbidity and granule diameter. Swelling power showed a negative correlation with solubility and setback. T_o, T_p and T_c showed positive correlation with turbidity, pasting temperature and were negatively correlated to peak and breakdown viscosity.     

Effect of germination and dehulling on functional properties of legume flours

The functional properties of flours derived from selected legumes were studied before and after dehulling of the germinated seeds. Ungerminated seeds were used as the control. The chosen legumes were green gram (Phaseolus aureus), cowpea (Vigna catjang), lentil (Lens culinaris) and bengal gram (Cicer arietinum). Dehulled samples had a higher protein solubility compared with germinated and control samples. The bulk densities of germinated and dehulled legume flours were lower compared to control. Germination increased water absorption capacities of legume flours from 1226, 1285, 974 and 1362 g kg^?1 to 1481, 1433, 1448 and 1517 g kg^?1 in green gram, cowpea, lentil and bengal gram, respectively. Fat absorption capacities increased in germinated samples (1130, 1242, 920 and 837 g kg^?1) as against 900, 993, 857 and 788 g kg^?1 at ambient conditions for green gram, cowpea, lentil and bengal gram, respectively. On dehulling, the fat absorption capacities of samples were reduced and the differences were statistically significant. The emulsification capacities of control samples ranged from 55 to 193 ml oil emulsified per gram of sample. On germination and dehulling, the emulsification capacities, activities and stabilities of samples increased significantly. There were increases in foaming capacities and reduction in foam stabilities of all the samples investigated on germination and dehulling. Thus, the study indicated that germination and dehulling improved the functional properties of legumes. Copyright © 2006 Society of Chemical Industry     

Relationships Between Selected Properties of Seeds,Flours, and Starches from Different Chickpea Cultivars

ABSTRACT

Five desi (PBG-1, PDG-4, PDG-3, GL-769, and GPF-2) and one kabuli type (L-550) chickpea cultivars were evaluated for their seed mass, volume, hydration capacity, swelling capacity, cooking time, and instrumental textural properties (hardness, cohesiveness, gumminess, and chewiness). Flour was prepared from these chickpea cultivars and various physicochemical and functional properties were determined. The pasting (pasting temperature, peak viscosity, breakdown, and final viscosity) and gelatinization (T _o, T _p, T _c, and ΔH _gel) properties of these flours were measured using Rapid Visco Analyzer (RVA) and Differential Scanning Calorimeter (DSC), respectively. Starch was also isolated from chickpea cultivars and evaluated for amylose content, swelling power, solubility, and syneresis values. Physicochemical, cooking, and instrumental textural properties of seeds of different chickpea cultivars were related to physicochemical, gelatinization, and pasting properties of their flours and physicochemical properties of their starches. Selected properties of chickpea seeds were significantly correlated with the properties of their starches and flours. Hardness value of soaked chickpea seeds was positively correlated to cooking time, seed mass, seed volume, hydration, and swelling capacity (p < 0.01). Water solubility index (WSI) of chickpea flours was positively correlated to seed mass, volume, hydration capacity, and hardness value (p < 0.05). Selected instrumental textural parameters of seeds had positive correlation with ΔH _gel of flours (p < 0.01). Peak viscosity of flours showed positive correlation to breakdown, final viscosity, bulk density, and negative correlation to cohesiveness of soaked seeds (p < 0.01). Final viscosity showed negative correlation to bulk density and water absorption index (WAI) (p < 0.01) of flours.     

Evaluation of processed green and ripe mango peel and pulp flours (Mangifera indica var. Chokanan) in terms of chemical composition,antioxidant compounds and functional properties

BACKGROUND: Mango is a highly perishable seasonal fruit and large quantities are wasted during the peak season as a result of poor postharvest handling procedures. Processing surplus mango fruits into flour to be used as a functional ingredient appears to be a good preservation method to ensure its extended consumption. RESULTS: In the present study, the chemical composition, bioactive/antioxidant compounds and functional properties of green and ripe mango (Mangifera indica var. Chokanan) peel and pulp flours were evaluated. Compared to commercial wheat flour, mango flours were significantly low in moisture and protein, but were high in crude fiber, fat and ash content. Mango flour showed a balance between soluble and insoluble dietary fiber proportions, with total dietary fiber content ranging from 3.2 to 5.94 g kg^?1. Mango flours exhibited high values for bioactive/antioxidant compounds compared to wheat flour. The water absorption capacity and oil absorption capacity of mango flours ranged from 0.36 to 0.87 g kg^?1 and from 0.18 to 0.22 g kg^?1, respectively. CONCLUSION: Results of this study showed mango peel flour to be a rich source of dietary fiber with good antioxidant and functional properties, which could be a useful ingredient for new functional food formulations. Copyright © 2011 Society of Chemical Industry     

Effects of rice properties and emulsifiers on the quality of rice pasta

Two commercial rice flours (GTIndica and GTJaponica, with amylose contents of 306.8 and 185.2 g kg^?1 respectively) and their blended flours were used to make rice pasta. The effects of two emulsifiers (distilled glyceryl monostearate (GMS) and a commercial emulsifier (KM3000)) on the pasting and thermal properties of dried rice pasta were investigated using a Rapid Visco Analyser (RVA) and a differential scanning calorimeter (DSC). The rice pasta made from high‐amylose rice flour had better extrusion properties, better texture, whiter colour, less cooking loss and better eating quality than that made from low‐amylose rice flour. The maximum amount of low‐amylose rice flour that could be blended in for making an acceptable quality of rice pasta was 500 g kg^?1. A soft texture, low adhesiveness and low gumminess of cooked rice pasta were obtained by adding 10 g kg^?1 GMS. SEM investigations showed that use of an emulsifier restricted the swelling of starch granules, especially for the pasta made from high‐amylose rice flour. © 2001 Society of Chemical Industry     

Flavonoid content and antioxidant capacity of spinach genotypes determined by high‐performance liquid chromatography/mass spectrometry

BACKGROUND: Flavonoids in different spinach genotypes were separated, identified, and quantified by a high‐performance liquid chromatographic method with photodiode array and mass spectrometric detection. The antioxidant capacities of the genotypes were also measured using two antioxidant assays–oxygen radical absorbance capacity (ORAC_FL) and photochemiluminescence (PCL)–which measure the response to the peroxyl and superoxide anion radicals, respectively. RESULTS: Eighteen flavonoids representing glucuronides and acylated di‐ and triglycosides of methylated and methylene dioxide derivatives of 6‐oxygenated flavonols were identified (patuletin, spinacetin, spinatoside, jaceidin). The total flavonoids ranged from 1805 to 3703 mg kg^?1, indicating 2.0‐fold variation among genotypes. The ORAC_FL and PCL values ranged from 48.7 to 84.4 mmol kg^?1 and from 9.0 to 14.0 mmol kg^?1, respectively, representing as much as 1.7‐fold variation among genotypes. CONCLUSION: The ORAC_FL and PCL values were highly correlated with total flavonoid content (r_xy = 0.96). Copyright © 2008 Society of Chemical Industry     

Chemical,biological and sensory evaluation of pasta products supplemented with α‐galactoside‐free lupin flours

α‐Galactoside‐free lupin flour has been used to supplement durum wheat semolina flour in order to increase the nutritive value of pasta products. Supplemented pasta products had a shorter cooking time, higher cooking water absorption, cooking loss and protein loss in water than control pasta prepared with only semolina. Sensory evaluation of cooked pastas showed that products supplemented with 80 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Emir flour or with 100 g kg^?1 of α‐galactoside‐free Lupinus angustifolius var. Troll flour showed the same acceptability by panellists as the semolina pasta. These levels of supplementation were selected for further studies. The cooked α‐galactoside‐free lupin/semolina pastas showed higher amounts of protein, dietary fibre, calcium, phosphorus, magnesium, zinc and antioxidant capacity than control pasta and a reasonable level of vitamin B₁, vitamin B₂ and vitamin E. Biological assessment of cooked pastas indicated that the true protein digestibility did not change after the fortification of semolina but protein efficiency ratio increased sharply in the pasta supplemented with α‐galactoside‐free lupin flours (2.07 and 1.92 for Emir and Troll lupin varieties, respectively) in comparison with the control pasta (1.11). It is concluded that the α‐galactoside‐free lupin flours are an adequate ingredient to improve the nutritional quality of pasta products without adding flatulent oligosaccharides. Copyright © 2006 Society of Chemical Industry     

Impact of α‐amylase and maltodextrin on physicochemical,functional and antioxidant capacity of spray‐dried purple sweet potato flour

BACKGROUND: Purple sweet potato flour could be used to enhance food products through colour, flavour and nutrients. Purple sweet potato flour has not yet been prepared with maltodextrin and amylase treatment using spray drying. Thus, the investigation was to evaluate the effect of various levels of maltodextrin (30 and 50 g kg^?1 w/v), amylase (3 and 7 g kg^?1 puree) and combined with maltodextrin and amylase on the physicochemical, functional and antioxidant capacity of spray dried purple sweet potato flours. RESULTS: Amylase and amylase with maltodextrin‐treated flours had a higher anthocyanin and total phenolic content than the control and maltodextrin‐treated flours. However, the antioxidant capacity was higher in the control and maltodextrin‐treated flours compared to the amylase and amylase with maltodextrin‐treated flours. The control had a higher water absorption index and lower water solubility index compared to the maltodextrin and combined with amylase and maltodextrin‐treated flours. On the other hand, maltodextrin increased whereas α‐amylase decreased the glass transition temperature. With respect to morphology, the particles of amylase‐treated flours were smaller than the control and maltodextrin‐treated flours. CONCLUSION: The results showed that good quality flour could be prepared by combining 30 g kg^?1 maltodextrin and 7 g kg^?1 amylase treatment. Copyright © 2009 Society of Chemical Industry     

Thermo‐physical properties of composite bread dough with maize and cassava flours

Composite wheat–cassava and wheat–maize flours were produced in ratio 100:0. 60:40, 50:50, 40:60 and 0:100 respectively. Thermo‐physical properties of bread dough were determined. For wheat –cassava composite bread dough, moisture content ranged between 44.02 ± 2.04 to 51.31 ± 2.99% dry basis (db), density (1035.2 ± 20.4 to 975.6 ± 12.6 kg m^?3), specific heat capacity (2.51 ± 0.61 to 3.01 ± 0.42 kJ kg^?1 K) and thermal conductivity (0.362 ± 0.13 to 0.473 ± 0.12 W mK^?1). While wheat–maize mixture gave 44.14 ± 1.94 to 45.09 ± 1.26%(db) of moisture content, 981.4 ± 16.3–960.4 ± 22.5 kg m^?3 density, 1.77 ± 0.17–2.61 ± 0.63 kJ kg^?1 K specific heat capacity and 0.36 ± 0.07–0.39 ± 0.02 W mK^?1 thermal conductivity. Effects of substitutions was significant on moisture content and thermal conductivity of dough while non significant influence was recorded on density and specific heat capacity at P < 0.05.     

Antioxidant and anti‐hypertensive activity of anthocyanin‐rich extracts from hulless pigmented barley cultivars

Anthocyanin‐rich acetone extracts of barley grain of four hulless pigmented genotypes were investigated to determine their potential as functional food ingredients. The purple barley cultivar contained 11 anthocyanins, whereas only one anthocyanin, peonidin derivative, was observed in blue, black and yellow barley. The total anthocyanin content of pigmented barley genotypes ranged from 3.2 to 678.5 mg kg^?1 in whole grain and from 4.5 to 1654.6 mg kg^?1 in bran. The purple barley bran extract gave the highest DPPH radical scavenging capacity, superoxide radical scavenging capacity and total antioxidant activity. The half maximal inhibitory concentration (IC₅₀) of angiotensin I‐converting enzyme (ACE) of anthocyanin‐rich extract of purple barley grain and bran was 8.77 and 4.54 mg mL^?1, respectively. Purple barley appears to have great potential uses for the promotion of human health and development of nutraceuticals and functional foods.     

Effect of cross‐linking on some properties of potato (Solanum tuberosum L.) starches

Starches separated from different potato cultivars were modified using two different cross‐linking agents: epichlorohydrin (EPI) and phosphoryl chloride (POCl₃) at different concentrations (1.0 and 2.0 g kg^?1 POCl₃; 2.5, 5.0 and 10 g kg^?1 EPI). Differential scanning calorimetry, rheological and retrogradation measurements were performed to characterise the influence of cross‐linking on the properties of potato starches. Cross‐linking considerably reduced swelling power, solubility, water‐binding capacity and paste clarity. The decrease became greater as the reagent concentration increased. The starches treated with 1.0 g kg^?1 POCl₃ exhibited exceptionally higher swelling power than their counterpart native starches. Neither cross‐linking agent caused any change in morphology of the starch granules. Studies on the phase transitions associated with the gelatinisation showed significantly higher values for the onset temperature (T_o), peak temperature (T_p), conclusion temperature (T_c) and enthalpy of gelatinisation (ΔH_gel) for the cross‐linked starches than the native starches. Starches treated with both the reagents showed lower peak storage modulus (G′) and loss modulus (G″) than their native counterparts. The tendency of the starch pastes towards retrogradation increased considerably with increases in storage duration. However, the starches treated with 1 g kg^?1 POCl₃ exhibited much lower syneresis than the other cross‐linked starches. Copyright © 2006 Society of Chemical Industry     

Detection of Lathyrus sativus in processed chickpea‐ and red gram‐based products by thin layer chromatography

Excessive consumption of Lathyrus sativus leads to crippling, irreversible paralysis of both lower limbs, mainly in males. This is attributed to the presence of a non‐protein amino acid, β‐N‐oxalyl‐L ‐2,3‐diaminopropionic acid or β‐N‐oxalylamino‐L ‐alanine. Using a thin layer chromatography method developed in our laboratory, adulteration of chickpea and red gram with L sativus in pressure‐cooked batters could be detected at levels of 100 and 200 g kg^?1 respectively. When processed as a curried liquid dal, L sativus could be detected at 200 g kg^?1 in chickpea and 100 g kg^?1 in red gram. Processing into fried bhajiyas resulted in a detection limit of 200 g kg^?1 in both red gram and chickpea. © 2003 Society of Chemical Industry     

Phytic acid content of chickpea (Cicer arietinum) and black gram (Vigna mungo): varietal differences and effect of domestic processing and cooking methods

Phytic acid content of various cultivars showed a narrow variation: 7.48-8.00 g kg^?1 and 6.47-6.68 g kg^?1 for chickpea (Cicer arietinum L) and black gram (Vigna mungo L), respectively. Phytic acid was lowered significantly by the common methods of domestic processing and cooking including soaking, cooking, autoclaving and sprouting of the legume grains. Sprouting had the most marked phytic acid lowering effect followed by autoclaving and soaking. Cooking of soaked seeds lowered phytic acid by 20-26% in chickpea and 35-40% in black gram grains whereas the loss was 7-11% and 6-9% in these pulses, respectively, when unsoaked seeds were cooked.     

Physicochemical and structural characteristics of starches from Chinese hull‐less barley cultivars

Fourteen hull‐less barley cultivars, collected from four major cultivated areas in China, were employed to investigate the structural and physicochemical properties of their starches in this study. Relatively wide variations in physicochemical properties of the starches were observed. Amylose content ranged from 23.1% to 30.0%, swelling power and water solubility index ranged from 12.8 to 19.9 g g^?1 and 12.7% to 23.7% respectively. Peak viscosity was from 170 to 346 Rapid Visco Unit (RVU), peak temperature (T_p) of starch gelatinisation was from 55.6 to 61.8 °C and enthalpy of starch retrogradation ranged from 0.3 to 3.1 J g^?1. Weight‐based chain‐length proportions of fa, fb₁, fb₂ and fb₃ in amylopectins ranged from 21.65% to 24.95%, 44.48% to 49.44%, 15.56% to 17.19% and 9.83% to 16.66% respectively. Correlation analyses showed that amylose content was inversely related to pasting parameters and enthalpy of gelatinisation. Pasting properties and amylopectin structures were the most important parameters to differentiate starch properties among different hull‐less barley cultivars in this study. This work will be useful for exploring applications of Chinese hull‐less barley starches in food and non‐food industries.     

Molecular and physicochemical characterisation of starches from yam,cocoyam, cassava,sweet potato and ginger produced in the Ivory Coast

Granule sizes, macromolecular features and thermal and pasting properties of starches from seven tropical sources (Florido, Kponan and Esculenta yams, cocoyam, cassava, sweet potato and ginger) were compared with those of several well‐known cereal, legume and tuber starches. The aim of the study was to characterise some non‐conventional starches with a view to possibly marketing them. Amylose content varied from 148 mg g^?1 in Esculenta starch to 354 mg g^?1 in smooth pea starch. For total starches, weight‐average molar mass (M?_w) ranged between 0.94 × 10⁸ and 1.80 × 10⁸ g mol^?1 for potato and normal maize starches respectively. Gyration radius (R?_G) varied from 157 nm for ginger starch to 209 nm for normal maize starch. Gelatinisation enthalpy (ΔH) ranged between 9.8 and 20.7 J g^?1 for wheat and Florido starches respectively. Gelatinisation peak temperature (T_g) varied from 58.1 °C for wheat starch to 87.3 °C for ginger starch. Native starch granule mean diameter ranged between 5.1 and 44.5 µm for Esculenta and potato starches respectively. Cassava and potato starches had the highest swelling power and dispersed volume fraction at all treatment temperatures, while ginger starch had the lowest. Cocoyam starch had the highest and ginger starch the lowest solubility at 85 and 95 °C. Cassava starch was the most stable under cold storage conditions. Roots and tubers such as ginger and cassava produced in the Ivory Coast are new sources of starches with very interesting properties. Thus these starches could be isolated on an industrial level in order to market them. Copyright © 2007 Society of Chemical Industry     

Physicochemical,Pasting, and Functional Properties of Amaranth Seed Flours: Effects of Lipids Removal

The present work was carried out to evaluate physicochemical (composition, hunter color, and sodium dodecyl sulfate–polyacrylamide gel electrophoresis [SDS‐PAGE]), pasting, and functional properties (foaming, emulsification, water, and fat absorption capacity) of amaranth full‐fat flours from 6 lines/cultivars (AFs), and to see the effects of lipid removal/defatting on these properties. Protein, ash, and lipid content of AFs ranged between 12.5% to 15.2%, 3.0% to 3.5%, and 7.1% to 8.0%, respectively. The flours showed a number of bands between 97 and 7 kDa, with main subunits of approximately 58, 37, 33, 31, 23, and 16 kDa in the SDS‐PAGE profiles. The protein content and L* value increased, while b* values decreased following defatting for most of the lines/cultivars. The defatted flours (DAFs) had higher final viscosity and stability (lower breakdown viscosity) as compared to counterpart AFs. The protein profiling of the flours was not affected with the lipid removal/defatting. However, water absorption capacity and foam stability of the flours improved upon defatting. Principal component analysis revealed that pasting temperature was positively related to lipid content, while breakdown viscosity was negatively related to protein content. Foaming properties (capacity and stability) showed negative relationship with lipid content, and positive with protein content, ash content, water, and fat absorption capacity.     

Physical,functional and pasting properties of different maize (Zea mays) cultivars as modified by an increase in γ‐irradiation doses

Physical, functional and pasting properties of six maize (Zea mays) cultivars as modified by an increase in γ‐irradiation doses were investigated. From the L*, a* and b* measured, deltachroma, colour intensity and hue angle were calculated. Functional and physicochemical properties of maize flours were determined using standard methods and Rapid Visco Analyser, respectively. Often, the effect of γ‐irradiation on L*, a* and b* values within each cultivar was almost never significant but pronounced between the yellow and white cultivars. Generally, deltachroma, colour intensity and hue angle decreased with increased γ‐irradiation dose. Mean seed bulk density and 100 kernel weight varied from 0.73–0.77 g cm^?3 and 23.13–35.42 g, respectively. Loose and packed bulk densities, and water (WAC) and oil absorption capacities of the maize flours were not significantly affected by γ‐irradiation. WAC of nonirradiated and γ‐irradiated maize flours ranged from 1.54–1.62 and 1.09–1.70 g g^?1, respectively. Peak, trough, breakdown, final and setback viscosities decreased significantly (P < 0.05) with increased γ‐irradiation dose.     

Flavonol glycosides and antioxidant capacity of various blackberry and blueberry genotypes determined by high‐performance liquid chromatography/mass spectrometry

Flavonol glycoside composition and content in blueberry and blackberry extracts were determined using a high‐performance liquid chromatographic (HPLC) separation method coupled with photodiode array (PDA) and mass spectrometric (MS) detection. The hydrophilic antioxidant capacities of crude and fractionated flavonol extracts were also determined by the oxygen radical‐absorbing capacity (ORAC_FL) and photochemiluminescence (PCL) assays. Eight flavonols of quercetin and quercetin–sugar conjugates were identified in Kiowa blackberry, namely rutinoside, galactoside, methoxyhexoside, glucoside, pentoside, [6″‐(3‐hydroxy‐3‐methylglutaroyl)]‐β‐galactoside, glucosylpentoside and oxalylpentoside. Thirteen flavonols were detected in Ozarkblue blueberry. Of these, myricetin 3‐hexoside and 12 quercetin–sugar conjugates, namely rutinoside, galactoside, methoxyhexoside, glucoside, pentoside, glucosylpentoside, caffeoylglucoside, oxalylpentoside, rhamnoside, dimethoxyrhamnoside, acetylgalactoside and acetylglucoside, were identified. In Bluecrop blueberry, two additional quercetin–sugar conjugates were identified, namely glucuronide and caffeoylgalactoside. Quercetin glycosides accounted for 75% of total flavonols in the blueberry genotypes. Total flavonol contents ranged from 99 to 150 mg kg^?1 for blackberries and from 192 to 320 mg kg^?1 for blueberries. Quenching of peroxyl and superoxide anion radicals by the flavonol fractions ranged from 1.5 to 2.3 mmol Trolox equivalents (TE) kg^?1 and from 0.5 to 0.7 mmol TE kg^?1 respectively for blackberries and from 2.9 to 5.2 mmol TE kg^?1 and from 0.8 to 1.4 mmol TE kg^?1 respectively for blueberries. The HPLC method allowed for complete separation and identification of flavonols commonly found in blackberries, and blueberries. Our results showed that blueberry and blackberry genotypes varied significantly in flavonol content and antioxidant capacity. Even though total flavonol content did not correlate well with antioxidant capacity, their ability to scavenge peroxyl and superoxide anion radicals was apparent. Copyright © 2005 Society of Chemical Industry     

The determination of aflatoxins in spices by immunoaffinity column extraction using HPLC

Seventy‐five samples of different spices marketed in Turkey were purchased from bazaars, herbal shops and supermarkets. Equal amounts of paprika, chilli, black peppers and cumin were purchased and used to test and compare the amount of aflatoxin contamination. Two different analytical methods were examined for their efficacy by adding a known amount of aflatoxin to the blank samples of paprika. Twenty‐seven paprika, all the chilli powder and four ground black pepper samples were contaminated with aflatoxin B₁ in the range of 0.5–116.4, 1.6–80.4 and 0.3–1.2 μg kg^?1 respectively. Twenty‐three (30%) paprika and chilli powder samples were above the regulatory limits used in the European Union. No aflatoxin contamination was detected in the cumin samples at a detection limit of 0.2 μg kg^?1.