Volume 5 Special Issue 1 2011
POTATO V

How to reference: Comandini P, Cerretani L, Blanda G, Bendini A, Toschi TG (2011) Characterization of Potato Flavours: An Overview of Volatile Profiles and Analytical Procedures. In: Benkeblia N (Ed) Potato V. Food 5 (Special Issue 1), 1-14

Guest Editor

Noureddine Benkeblia

University of the West Indies, Jamaica

www.mona.uwi.edu/lifesciences

CONTENTS AND ABSTRACTS

Patrizia Comandini, Lorenzo Cerretani, Giampaolo Blanda, Alessandra Bendini, Tullia Gallina Toschi (Italy) Characterization of Potato Flavours: An Overview of Volatile Profiles and Analytical Procedures (pp 1-14)

Full Text [PDF]

ABSTRACT

Invited Review: Potatoes may be cooked by several methods such as boiling, baking and frying; they are also used as an ingredient for numerous home-made and mass-produced foods like sticks, chips and other snacks. An important factor affecting consumer preferences of these products is their flavour, which is defined as the combined perception of aroma, taste and mouthfeel sensations. Flavour, and in particular the volatile profile of potatoes, has been widely investigated in the last few years, and complex patterns have been found. Although raw potatoes possess little aroma, more than 140 volatile compounds have been identified in boiled potatoes, whereas over 250 have been found in baked potatoes and more than 500 compounds have been isolated in French fries. Among these, many lipid oxidation and Maillard reaction products have been reported, together with smaller amounts of indigenous flavour compounds. Many extraction methods have been developed to characterize the aroma of potatoes, with the goal of reducing analytical detection limits, avoiding formation of artefacts during isolation and reducing analysis cost and time; among these are distillation techniques, solvent and direct solvent extraction techniques, static and dynamic headspace methods and solid-phase microextraction. As regard isolation and quantification of potato volatiles, gas chromatography-mass spectrometry and gas chromatography/olfactometry are frequently used. The analytical approach is often completed with the sensory evaluations. This review describes the flavour profile of the main forms of cooked potatoes, taking into account their mechanism of generation; extraction and analysis procedures are also considered, reporting both conventional and innovative methods.

Elżbieta Rytel, Anna Pęksa, Agnieszka Tajner-Czopek, Agnieszka Kita, Grażyna Lisińska (Poland) Anti-nutritional Compounds in Potatoes, Depending on the Type of Raw Material and Conditions of Processing Potatoes into Food Products (pp 15-22)

Full Text [PDF]

ABSTRACT

Invited Review: The nutritional quality of potato, which is directed towards consumption or intended for food processing, is determined by the presence of nutritional components such as starch, protein or vitamins and also by the low content of anti-nutritional ingredients in potato tubers. Anti-nutritional components in potato exist naturally in tubers, are created as effects of destabilization of the plant’s metabolism, or they can be absorbed from a polluted environment. The most common natural anti-nutritional ingredients in potato include nitrates V, toxic glycoalkaloids and nitrates III, although heavy metals and pesticides used during potato cultivation can penetrate potato tubers. Usually, potatoes used in the food industry originate from conventional cultivation, which is characterized by heavy fertilization and plant protection. This could be a reason for the increase in toxic components as well as anti-nutritional ingredients – mainly glycoalkaloids (solanine and alpha-chaconine) and nitrates – in potato tubers. The technology used in the production of French fries, chips or dried potato products depends on the parameters used at particular stages of the production line, affecting the content of those components in processed potatoes to a different degree. The differences in the content of glycoalkaloids and nitrates can appear not only because of the differences in the methods used to’ peel or cut potato tubers, but also because of the different parameters (time and temperature) used during three key processes: blanching, frying and drying. High temperatures used in the processing of potato products also need to take into consideration the development of acrylamide.

Sebastián D’Ippólito, María Cecilia Terrile, Andrea Verónica Godoy, Claudia Anahí Casalongué, Diego Fernando Fiol (Argentina) Identification and Expression of Stress-responsive Genes to Fusarium solani f. sp. eumartii Infection in Potato Tubers: Old and New Candidates (pp 23-26)

Full Text [PDF]

ABSTRACT

Original Research Paper: In order to identify genes involved in the potato (Solanum tuberosum L.) tuber response to the pathogenic fungus Fusarium solani f. sp. eumartii (F. eumartii) a differential screening of infected-potato cDNA library was carried out. In this work, we identified potato cDNA clones coding for a heat shock protein, StHSP90 and four ribosomal proteins corresponding to small and large subunits, StS9, StS19 and StL3, StL36, respectively. Total RNA was extracted from non-wounding, wounding and wounding plus F. eumartii-infected tubers. The pattern of RNA accumulation for each gene was investigated by northern blot assays. Compared with control tubers, StHSP90 and StL36 genes were up-regulated by wounding and F. eumartii attack. StS9, StS19 and StL3 transcript levels showed a 2-fold increase upon F. eumartii infection. However, their expression profiles did not change by wounding. In addition, StS9 transcript level was accumulated in salicylic acid- and jasmonic acid-treated leaves. In conclusion, our findings bring evidence on new different kinds of stress-responsive genes that may counteract F. eumartii attack in potato tubers. Putative functions for HSP90 and ribosomal proteins are discussed.

María Dolores Alvarez, Cristina Fernández, Wenceslao Canet (Spain) Flow Behaviour and Sensory Properties of Extra Virgin Olive Oil-Enriched Mashed Potatoes: Influence of Cryoprotectants and Freezing (pp 27-39)

Full Text [PDF]

ABSTRACT

Original Research Paper: Extra virgin olive oil (EVOO) has interesting nutritional characteristics, which are linked to its biophenols content with very important antioxidant properties. The aims of this work were to investigate the effect of the addition of EVOO at four concentrations (0, 10, 25 and 50 g kg^-1) on flow behaviour and sensory attributes of fresh and frozen/thawed mashed potatoes (FMP and F/TMP respectively) formulated with and without added cryoprotectants (kappa-carrageenan (κ-C) and xanthan gum (XG) (each cryoprotectant at 1.5 g kg^-1). Other steady shear and yield stress data, colour, expressible water (E_w) and overall acceptability (OA) were also examined. All the samples displayed shear-thinning flow behaviour. Results showed that between the factors under consideration, EVOO concentration was the factor that set the minor difference among the most of the rheological properties, whereas the addition of κ-C + XG resulted in main differences between mashed potatoes (MP). However, EVOO concentration set the major difference among the OA of the samples. Increase of EVOO content produced softer systems due to increasing droplet concentration, whereas addition of cryoprotectants led to more structured systems related to the gelling properties of κ-C. Processing also affected the flow behaviour of the MP, but the effect depended on the absence or presence of cryoprotectants. EVOO would appear to provoke perceptions of creaminess/softness, whereas κ-C and XG provokes perceptions of creaminess/thickness. Very good correlations with sensory perceived consistency were found in the cases of pseudoplasticity for the FMP samples (r² = 0.947) and apparent viscosity for the F/TMP ones (r² = 0.935). These results have important implications for the production of F/TMP with improved sensory quality and freeze–thaw stability, at once that giving a functional value to the product.

Kerstin Skog, Gunilla Viklund, Kerstin Olsson, Ingegerd Sjöholm (Sweden) Acrylamide in Home-prepared Roasted Potatoes – Influence of Growing Location and N-Fertilisation (pp 40-42)

Full Text [PDF]

ABSTRACT

Short Communication: Acrylamide is a probable human carcinogen that is formed during heating of carbohydrate-rich foods. The formation goes via the Maillard reaction between the precursors sugars and the amino acid asparagine, and at the same time brown colour, taste and crispiness are formed. Most mitigation strategies have been devoted to industrially prepared foods, and data on acrylamide in home-cooked foods are scarce. For national food authorities there is a need to collect such scientific data as a basis for advice to consumers on healthy cooking. In this study, the concentrations of the acrylamide precursors, asparagine and sugars (glucose, fructose and sucrose), were determined in four potato varieties (‘Asterix’, ‘Bintje’, Princess’ and ‘Superb’), grown at two different locations in the south of Sweden. Nitrogen had been given at two levels (60 and 120 kg N/ha) during growth. Potato wedges were prepared and roasted in two domestic ovens according to common home-cooking practices and analysed for acrylamide. The acrylamide concentrations ranged from 57 to 457 µg/kg dry matter. Nitrogen fertilisation had no significant effect on precursor content or acrylamide levels. The growth location had a large influence on the content of sugars in the tubers and on the content of acrylamide in the roasted potato wedges. The temperature profiles in the ovens fluctuated and differed between the ovens and our results indicate that there is a need for better temperature control in domestic ovens. For a 200 g portion of oven roasted potato wedges, the acrylamide content may be estimated to range from 3 to 27 µg giving a significant contribution to the dietary acrylamide intake.

Lu Te Chuang (Taiwan), Robert H. Glew (USA), Yuan Chen Wang, Pei Wun Yao, Chih Cheng Lin (Taiwan), Jack M. Presley, John Schulze USA), Chien Wei Hou (Taiwan) Comparison of the Fatty Acid, Amino Acid, Mineral and Antioxidant Content of Sweet Potato Leaves Grown on Matsu Island and Mainland Taiwan (pp 43-47)

Full Text [PDF]

ABSTRACT

Original Research Paper: Sweet potato leaves (SPL) are a green leafy vegetable valued for their low carbohydrate and high essential-nutrient content. The aim of this study was to increase knowledge of the nutrient composition of SPL by analyzing SPL cultivated on Matsu and Hsinchu, Taiwan for antioxidants, amino acids, fatty acids, and minerals and trace elements. With the exception of antioxidants, in general, SPL from Matsu contained significantly more of these nutrients than those from Hsinchu. Methanol extracts of Hsinchu SPL contained 359 mg/g dry wt of polyphenols compared to 129 mg/g in leaves from Matsu and twice the radical-scavenging activity of the Matsu specimens. The leaves from Matsu contained more of 7 of 11 essential minerals than those from Hsinchu, including: Zn, Fe, Cr, Se, Ca, Mg, and P. Matsu and Hsinchu SPL contained 13.8 and 17.1% protein (P = 0.001), respectively, and the proportions of all essential amino acids in both sets of specimens, except for methionine plus cysteine (score, 46-54), exceeded those of a World Health Organization reference protein which are set at 100. The fatty acid content of the leaves from both sites was low (1.54-1.60%); however, the healthful ω-3 essential fatty acid α-linolenic acid accounted for 48.3-53.4 of the total, whereas the ω-6 essential fatty acid, linolenic acid contributed only about 12% to the fatty acid total. In conclusion, these results demonstrate that while the leaves of sweet potato are a good source of many essential nutrients, the amounts of protein, antioxidants, and minerals and trace elements and the fatty acid composition of SPL in Taiwan varied significantly between the two sites where they were cultivated. These differences are likely related to climate and soil quality.

Faik A. Ayaz (Turkey), Robert H. Glew (USA), İbrahim Turna, Deniz Güney (Turkey), Lu-Te Chuang, Y.-C. Chang (Taiwan), Ronny Andrews, Laura Power, John Presley (USA), Hülya Torun, Nesrin Sahin (Turkey) Fagus orientalis (Oriental Beechnut) Seeds are a Good Source of Essential Fatty Acids, Amino Acids and Minerals (pp 48-51)

Full Text [PDF]

ABSTRACT

Original Research Paper: Oriental beechnut (Fagus orientalis Lipsky) is a decidious tree that is native to Turkey. Although beechnut seeds are widely consumed by the local population, knowledge of their nutrient composition is incomplete. The main purpose of this study was to determine the content of fatty acids, amino acids, and minerals and trace elements in oriental beechnut seeds. Seeds collected from five sites in the Black Sea region and another in the Mediterrenean region were dried, milled and analysed. Whereas the results for the seeds from the five Black Sea sites were similar, those for seeds from the Mediterranean region were slightly different. Fatty acids accounted for 45.0% of the dry weight of the seeds of which 40, 34.1 and 3.66% was contributed by oleic, linoleic and a-linolenic acids, respectively. The average protein content was 22.5%; however, the proportions of the essential amino acids lysine, threonine and tryptophan fell below those of the World Health Organization protein standard. Beechnut seed contained nutritionally significant amounts (mg/g dry weight) of calcium (4821), copper (18.1), iron (41.6), magnesium (2053), manganese (619) and zinc (27.8), but reletively low amounts of molybdenum (0.3) and selenium (0.5). This study demonstrates that seeds of oriental beech are a good source of many nutrients essential to human wellbeing.

Mezajoug Kenfack Laurette Blandine (Cameroon), Arab–Tehrany Elmira (France), Tchiégang Clergé (Cameroon), Linder Michel (France) Compositional and Nutritional Studies of Two Defatted Flours Obtained from Ricinodendron heudelotii (Bail.) and Tetracarpidium conophorum (Müll. Arg.) (pp 52-57)

Full Text [PDF]

ABSTRACT

Original Research Paper: The chemical composition and nutritional value of two edible Euphorbiaceae (Ricinodendron heudelotii and Tetracarpidium conophorum) from Cameroon were determined. Protein content of defatted flours from these plants was high (44.5 – 47.9% of dry weight). Dietary fiber contents were 9.7 and 10.9%, respectively. Phospholipids were in low quantities and they were close to 9% of dry weight in both defatted flours, with oleic and linoleic acids representing more than 33% of total fatty acid. For all the essential amino acids the amount in T. conophorum defatted flour exceeded the value in FAO/WHO (2007) scoring pattern. There were no significant (P > 0.05) differences between the values obtained for Protein Efficiency Ratio, Net Protein Ratio, True Digestibility and Net Protein Utilization of diets containing T. conophorum and casein. True Digestibility Corrected Amino Acid Scores and Net Protein Utilization Corrected Amino Acid Scores were more than 150% with T. conophorum defatted flour, indicating the nutritional superiority of this sample.

Ka-Soon Lee, Gwan-Hou Kim, Hyun-Ho Kim, Bong-Jae Seong, Sun-Ick Kim, Seung-Ho Han, Byeong-Ha Yun (South Korea) Physiological Characteristics of Medicinal Herbs Soysauce with Ripening Period (pp 58-63)

Full Text [PDF]

ABSTRACT

Original Research Paper: This study was carried out to investigate the physiological characteristics of medicinal herbs soysauce (MHSS), after adding 24 kinds of medicinal herbs, with ripening period. Total nitrogen compound content increased up to 5 years after which there were no significant differences; the peptide-N content increased up to 5 years and decreased thereafter, while formol- and amino-type N content gradually increased up to 10 years. The major isoflavones of MHSS were daidzin, genistin and genistein, accounting for 128.7~130.7, 113.7~128.5 and 96.8~104.6 µg/g, respectively. After 10 years ripening of MHSS, free type of daidzin doubled while conjugated type of genistin decreased by 30%. When the ripening period was increased, DPPH radical scavenging and SOD-like activity, as well as ACE inhibitory ability and nitrite scavenging effects increased: the IC₅₀ value of MHSS ripened for 10 years for DPPH radical scavenging activity was < 0.1 mg, SOD-like activity was 82.5% at 5 mg/mL of MHSS, nitrite scavenging effect was 60.1% (pH 1.2) at 5 mg/mL of MHSS and the ACE inhibitory ability of 9-year-old ripened MHSS was highest, at 89.1 ± 1.5%.

Rose Koffi-Nevry, Marina Koussémon, Kablan Tano, Firmin Aboua (Côte d’Ivoire) Chemical and Sensory Characteristics of two Types of Cassava Pulp during their Processing into Bedecouman (pp 64-67)

Full Text [PDF]

ABSTRACT

Original Research Paper: This study was undertaken to analyze and compare the chemical composition and sensory characteristics of bedecouman made from two cassava pulps at various stages of its preparation. The fermented cassava dough contained 54-56.7% moisture, 2.06-1.98% proteins, 0.20% lipids, 1.15-1.1% ash, and 23.86-23.65% starch for the white and yellow pulp respectively. The investigations showed respectively 68.35-69.3% moisture, 1.04-1.01% proteins, 0.28-3.9% starch and 0.17-0.2% lipids for the white and the yellow bedecouman. The end product had a mean hydrocyanic acid content of 52.12 and 55 mg HCN/kg for the white and yellow pulp, respectively and for the fermented cassava dough 155.62 and 135 mg HCN/ kg. High rating was given to the flavor for the white pulp (8.92), then homogeneity (uniformity of the appearance) 8.16 and 7.50 for the white and yellow pulp, respectively. There was a significant difference between the types of pulp especially for color and flavor. Boiling was more efficient than natural fermentation in reducing the HCN.

Dorra Sfayhi, Mohamed Kharrat (Tunisia) Physicochemical and Cooking Characteristics of Tunisian Chickpea Varieties (pp 68-72)

Full Text [PDF]

ABSTRACT

Original Research Paper: Seed weight, size and volume, hydration and swelling capacities and cooking time of six Tunisian Kabuli chickpea varieties were evaluated and compared to one Desi accession. Physicochemical characteristics (water solubility and water absorption indices, bulk density and hunter color) of flours were determined for all of them. The Tunisian chickpea varieties showed higher seed weight, size and volume than the Desi type. This tendency was also observed for swelling and hydration capacities and cooking time. Cooking time was positively correlated with hydration capacity (R²=0.67), and was positively correlated to seed size (R²=0.77). Concerning the physicochemical characteristics of chickpea flours, significant variability between Tunisian chickpea varieties was observed. Compared to Desi type ‘JG62’, they presented lighter flours with low bulk density ranging between 0.6 and 0.67 g/ml and high water solubility index varying between 25.2 and 30.8%.

Charles Falang Doumta, Clergé Tchiégang (Cameroon) Physicochemical Characterisation of Parkia biglobosa Benth Seed in View of Improving Daddawa Condiment Production in Cameroon (pp 73-78)

Full Text [PDF]

ABSTRACT

Original Research Paper: Daddawa is a food condiment produced by fermentation of African locust bean seed (Parkia biglobosa Benth). Several difficulties are encountered during the transformation of these seeds into Daddawa. To overcome these difficulties, it is important to calibrate the seeds in different classes, to evaluate their physico-chemical properties before cooking at 96°C using the traditional method. The cooked seeds were manually dehulled and the number of dehulled seeds was evaluated. The results showed that the seed mass varies from 0.17-0.55 g, length from 0.90-1.50 cm, width from 0.70-1.10 cm and thickness between 0.30-0.60 cm. Calibre 1 (mass < 0.30 g), calibre 2 (0.30 g ≤ mass ≤ 0.40 g) and calibre 3 (mass > 0.40 g) were identified on a mass basis. Cotyledon chemical composition [lipid (20.39-22.9 g/100 g); total carbohydrates (34.24-39.59 g/100 g); total proteins (73.60-77.27 g/100 g) and total ash (5.92-7.09 g/100 g)] increased with the calibre, while the seed coat and number of seeds/kg decreased. The percentage of dehulled seeds was lower with calibre 1 (51.25 ± 1.88%) while whole sample, calibre 2 and 3 were 61.75 ± 2.75, 69.0 ± 3.0 and 70.0 ± 7.0%, respectively. Seeds (calibre 1) with a high percentage of seed coat (33.72 ± 0.64 %) needed a long cooking time (more than 10 hours) than those (calibre 2 and 3) with a low percentage of seed coat (30.66-31.17%) during the softening process. Calibre 2 and 3 had the lowest amount of seed coat and highest percentage of dehulled seed. These calibres could be used to reduce the cooking time of seed during the softening process.

Dasel Wambua Mulwa Kaindi (Kenya), Esther Schelling (Switzerland), John Wangoh, Jasper Kathenya Imungi (Kenya), Zakaria Farah, Leo Meile (Switzerland) Microbiological Quality of Raw Camel Milk Across the Kenyan Market Chain (pp 79-83)

Full Text [PDF]

ABSTRACT

Original Research Paper: The objective of this study was to determine the microbiological quality of camel milk at critical points along the market chain. 36 camel milk samples were assessed by plating counts of total bacteria (TBC), Streptococcus/Enterococcus (PSEC), yeast and mold (YMC), Enterobacteriaceae (EBC), and Staphylococcus (PSC). At milking level all milk samples had TBCs not exceeding 10⁵ cfu ml^-1. EBC exceeding 10³ cfu ml^-1 indicating grade II quality was found in 25% of primary collectors’ milk. 75% of bulked milk at the final market had TBC exceeding 10⁶ cfu ml^-1 and EBC of 5.0 × 10⁴ cfu ml^-1; grade III and IV quality of raw milk an indicator of poor quality and threat to human health according to Kenya quality standards. All microbiological counts increased along the market chain with milk pH changing from 6.49 at milking level to 6.39 at final market. The air and water at the milking level were grossly contaminated while milk containers at milking and primary collection centers needed more appropriate sanitization procedures.

Hana Zandkarimi, Alireza Talaie, Reza Fatahi (Iran) Evaluation of Cultivated Lime and Lemon Cultivars in Southern Iran for Some Biochemical Compounds (pp 84-88)

Full Text [PDF]

ABSTRACT

Original Research Paper: There were no significant differences in the contents of total dietary fiber in the cultivars of lime (Citrus aurantifolia Swing cvs. ‘Persian’ and ‘Roodan’) and lemon (Citrus limon L. Burm cvs. ‘Lisbon’ and ‘Meyer’) tested but the contents of total dietary fiber in peel were significantly higher than pulp (P < 0.05). The content of total polyphenols showed significant differences in each part and in each cultivar. The highest total phenolic content was in leaves which ranged from 99.75 ± 0.68 to 129.42 ± 0.48 mg gallic acid/100 g DW than in green and yellow peels, petals, pulp and seed of all cultivars. Carotenoid and pectin contents were significantly different in the different parts of cultivars, significantly higher in fruit peel than in pulp. Lemon juice had higher antioxidant activity, TSS and pH than limes but lower ascorbic acid, EC and titratable acidity than lime juice. In conclusion, the peels of all cultivars were rich in dietary fiber, pectin and total carotenoid. All fruit parts of lemon cultivars had highest polyphenolic content. Peel and pulp of lime fruits showed highest pectin content.

Ogechi C. Nzeagwu, Justina C. Akagu (Nigeria) Food Habits and Nutritional Status of Nigerian Undergraduates (pp 89-95)

Full Text [PDF]

ABSTRACT

Original Research Paper: The food habits, nutritional status and nutritional knowledge of undergraduates in two tertiary Institutions in Abia State - Michael Okpara University of Agriculture, Umudike (MOUAU) and Abia State University, Uturu (ABSU) was carried out. A cross sectional survey was carried out on 342 subjects [150 (59 males, 91 females) from MOUAU and 192 (69 males, 123 females) from ABSU] from ages 16-25 years who were randomly selected. Pretested and validated questionnaire was used to obtain information on socio-economic characteristics, food habits and nutrition knowledge while anthropometric characteristics were used to determine their nutritional status. Data was analysed using descriptive statistics and Pearson’s correlation. The highest factor that determined food habits was economic factor. Breakfast was the highest skipped meal because of no time. The result of the body mass index (BMI) revealed that majority (MOUAU, 76.7%) and (ABSU, 75%) were in the normal category BMI (18.50-24.99 kg/m²). More than 70% of the respondents from the two institutions had good nutrition knowledge which was reflected in their food habits; however financial inadequacy and time constraint were the major factors that influenced the implementation of the nutrition knowledge. There was no significant difference (P > 0.05) between parental socioeconomic status and food habits, between body mass index and food habits. However, the parental socio-economic status and body mass index were significantly (P < 0.05) related.

Ramakrishnan Shamna, Jagathala Mahalingam Sasikumar, Engoor Sugathakumar Adithya, Paul Hephzibah Christabel, Mangalanandan Santha Lakshmi (India) Antioxidant Capacity of Rubus niveus Thunb. and Elaeocarpus oblongus Gaestn.Fruits (pp 96-101)

Full Text [PDF]

ABSTRACT

Research Note: In this study, antioxidant capacity of the crude methanolic extract of Rubus niveus and Elaeocarpus oblongus fruit was assessed for the first time. The methanolic extract of R. niveus and E. oblongus fruits displayed excellent scavenging capacity towards 1,1-diphenyl-2- picrylhydrazyl free radical (DPPH∙) (EC₅₀ = 0.200 ± 0.76 and 0.250 ± 1.76 mg mL^-1), superoxide anion (O₂·ˉ) (EC₅₀ = 0.50 ± 0.82 and 0. 50 ± 1.20 mg mL^-1), hydroxyl ion (˙OH) (EC₅₀ = 0.250 ± 0.22 and 0.500 ± 0.48 mg mL^-1) and nitric oxide (NO) (EC₅₀ = 0.250 ± 0.22 and 0. 250 ± 0.552 mg mL^-1). The results also showed that R. niveus and E. oblongus extracts had a strong reductive capacity (OD at 700 nm) (EC₅₀ = 0. 315 ± 1.32 and 0. 221 ± 0.52 mg ml^-1, strong ferric ion (Fe³⁺) chelation (EC₅₀ = 0.251 ± 1.02 and 0.251 ± 1.42 mg mL^-1) and remarkable reduction of lipid peroxidation (LPO) (EC₅₀ = 0.502 ± 0.24 and 0.502 ± 0.38 mg mL^-1). The antioxidant capacity of both extracts was comparable with antioxidant standards, butyl hydroxy toluene (BHT), EDTA (iron chelation) and catechin. The results of the present study revealed that the fruits of R. niveus and E. oblongus possess potent antioxidant activity.