Raw Peanuts Research Articles

Biology of a Neotropical Harlequin Stink Bug, Runibia perspicua (F.).

Laboratory and field studies were conducted with nymphs and adults of the Neotropical stink bug Runibia perspicua (F.) to evaluate their biology on plants. Total nymph mortality was ca. 13% on immature fruits of Brunfelsia australis Benth. (IFBA) and 90% on raw shelled peanuts, Arachis hypogaea L. (RSP); no nymphs survived on immature pods of green bean, Phaseolus vulgaris L., or on immature fruits of privet, Ligustrum lucidum Ait. Nymph developmental time was ca. 36 on IFBA and 55days on RSP. Body weight was significantly greater when nymphs were raised isolated compared to those raised in groups. Adult feeding activity was greater than third instars on IFBA. Adult longevity on IFBA + cherry tomato, Solanum lycopersicum L. fruit, reached ca. 150days. On IFBA, fecundity was 2.5 egg masses/female and 48.3 eggs/female; 25.6% of the eggs hatched. Adults did not reproduce on tomato. Body weight gain did not increase significantly for both sexes during the first four weeks of adult life on IFBA. In the field, plants of B. australis were surveyed in Passo Fundo, RS (28°15'S; 52°24'W). The majority of egg masses were deposited on the lower (abaxial) surface of leaves. Nymphs aggregated on immature fruits, and adults were seldom found on the plants. These are the first data on the performance of R. perspicua on B. australis indicating that this plant species is suitable to the bug's biology.

Extended Boiling of Peanut Progressively Reduces IgE Allergenicity While Retaining T Cell Reactivity

B Tao, K Bernardo, P Eldi. Clin Exp Allergy. 2016;46(7):1004–1014 To evaluate the impact of extended boiling on peanut allergenicity and T cell reactivity. Blood samples were collected from 10 peanut-allergic children ages 8 to 14 years with peanut-specific IgE ranging from 91.8 to >100 kU/L. Skin prick tests using boiled peanut extracts were performed on 20 known peanut-allergic children ages 2 to 16 years. Blood samples were collected for peanut antigen-specific T cell assays from 3 peanut-allergic patients and 3 nonallergic volunteer controls. Raw peanuts were boiled for 30 minutes, 1 hour, 2 hours, 4 hours, and 12 hours in deionized water. After …

Effect of solid state fermentation of peanut shell on its dye adsorption performance

The effect of solid state fermentation of peanut shell to produce beneficial laccase and on its dye adsorption performance was evaluated. The resulting residues from solid fermentation were tested as sorbents (designated as SFs) in comparison to the raw peanut shell (RPS) for their ability to remove crystal violet from water. The fermentation process reduced the adsorption capacity (qm) of SF by about 50%, and changed the sorptive behavior when compared to the RPS. The Langmuir model was more suitable for fitting adsorption by SFs. qm was positively correlated with the surface area of peanut shell, but negatively correlated with acid detergent lignin content. For all the sorbents tested, the process was spontaneous and endothermic, and the adsorption followed both the pseudo 1st and 2nd order kinetic model and the film diffusion model. Dye adsorption efficiency was greater when SFs dispersed solution than when placed in filter packets.

Influence of oven and microwave roasting on bioproperties, phenolic compounds, fatty acid composition, and mineral contents of nongerminated peanut and germinated peanut kernel and oils

While antioxidant activity values of nongerminated peanut kernel extracts change between 46.58% (raw peanut) and 49.63% (oven), this values of germinated kernel extracts varied between 38.67 (oven) and 44.83 mgGAE/100 g (germinated). In addition, total phenolic contents of both nongerminated and germinated peanut kernels changed between 12.68 (oven) and 19.73 mgGAE/100 g (raw) and 23.81 (oven) and 41.62 mgGAE/100 g (germinated), respectively. p-Hydroxybenzoic, vanillic, ferulic, quercetin, and p-coumaric and cinnamic acids were the dominant compounds of both germinated and nongerminated peanut kernels. It was observed statistically differences in fatty acid composition of peanut oils (p < .05). The highest oleic acid contents (62.74%) were determined in nongerminated kernel oil roasted in oven. The contents of α-tocopherol in nongerminated peanut ranged from 16.58 mg/100 g (oven roasted) to 18.64 mg/100 g (raw),while α-tocopherol contents of germinated kernel oils change between 14.72 mg/100 g (microwave roasted) and 16.49 mg/100 g (germinated). Mineral contents of germinated peanut kernels decreased partially compared to nongerminated peanut kernels. Practical applications Nut oils are receiving growing interest due to their high concentration of bioactive lipid components, which have shown various health benefits. Germination produced high phenolic content and antioxidant activities in lupin seeds. Phenolic compounds are generally secondary metabolite produced in plants, and they might be correlated to antioxidant activity, which has been shown to retain various biological benefits; microwave energy and conventional heating are currently being used for food processing operations, including cooking, drying, tempering, baking, pasteurization, and sterilization.

A metabolomics-based approach identifies changes in the small molecular weight compound composition of the peanut as a result of dry-roasting

Raw peanuts in the USA are subjected to thermal processing, such as dry-roasting, prior to consumption. A multi-instrument metabolomics-based platform along with targeted analyses was used to determine changes in the low-molecular-weight compound composition of peanuts due to dry-roasting. Runner and virginia-type peanut seeds were characterized using several analytical platforms including (RP)/UPLC-MS/MS (positive and negative ion mode ESI) and HILIC/UPLC-MS/MS with negative ion mode ESI. Of the 383 compounds identified, 16 compounds were unique to the roasted peanuts. Using pathway analysis, compounds associated with arginine and proline metabolism were found to be the most changed. Products of chemical degradation and compounds contained within the vesicular bodies of the peanut increased after roasting. Dry-roasting had a significant impact on the levels and types of low-molecular-weight compounds present. These findings provide useful information about composition changes due to roasting.

Peanut oleosins associated with severe peanut allergy—importance of lipophilic allergens for comprehensive allergy diagnostics

Peanut allergy is one of the most common and most severe food allergies in Western countries and its accurate diagnosis to prevent potential life-threatening allergic reactions is crucial. However, aqueous extracts used for routine diagnostic measurements are devoid of lipophilic allergens such as oleosins. We have recently succeeded in the isolation and purification of these unique proteins, and the present study evaluates their allergenic potential and clinical relevance. We sought to assess allergenicity and sensitization prevalence of oleosins obtained from both raw and in-shell roasted peanuts. In addition, we tested the utilization of natural and recombinant oleosins for allergy diagnostic purposes. Oleosin sensitization, prevalence, and impact of thermal processing were analyzed by immunoblot with sera from 52 peanut-allergic individuals displaying different clinical phenotypes. The application of natural and recombinant oleosins for allergy diagnostics was investigated by basophil activation test (BAT). IgE-binding epitopes were identified by oligopeptide microarray. Sensitization to oleosins was observed exclusively in peanut-allergic subjects suffering from severe systemic reactions. IgE-binding capacity of oleosins derived from in-shell roasted peanuts was increased as shown by immunoblot analysis and BAT. Both natural and recombinant molecules can be used to identify oleosin-sensitized patients by BAT. Alinear epitope of Ara h 15 was determined that displays high similarity to other seed-derived oleosins. Oleosins are clinically relevant peanut allergens and most likely associated with severe allergic symptoms. In-shell roasting increases their allergenicity, which is consistent with the observation that most allergic reactions are in connection with roasted peanuts.

Is peanut causing food allergy in Cuba? Preliminary assessment of allergic sensitization and IgE specificity profile to peanut allergens in Cuban allergic patients

Background Peanut allergy is increasing at an alarming pace in developed countries. Peanut (Arachis hypogaea) is a common food in Cuba. Nevertheless, reported values of sensitization and symptom severity are usually low. As our objective, we carried out an evaluation of allergic sensitivity to perform an assessment of allergic sensitization and IgE specificity profile to peanut allergens in Cuban allergic patients.Methods The Skin Prick Test (SPT) was performed for each patient, using two glycerinated allergenic extracts, prepared from raw or roasted peanuts. Overall, 316 food allergic patients (159 adults and 157 children) attending allergy services at four hospitals in Havana were included, as well as 303 adult non- allergic volunteers. The IgE binding profile of 26 selected SPT positive patients was further analyzed by immunoblotting.Results The prevalence of sensitization to peanut was 4.6% in general adult population, whereas in adult food-allergic patients it was 18.6%. Prevalence rates were even greater in food allergic children achieving 25.8%. Sensitization frequencies were apparently greater for roasted, as compared to raw peanuts, although the difference was not significant (p> 0.05, Mc Nemar's). IgE binding was shown mostly by the 15 and 17 kDa bands, tentatively identified as the major allergens Ara h 2 and Ara h 6. The IgG4 binding profile was similar to IgE, although with more prominence of the bands at 37 and 28 KDa, corresponding to an Ara h 3 fragment and Peanut Agglutinin.Discussion The study estimated a relatively high prevalence of peanut sensitization in population. Data reported here suggest that IgE sensitization in Cuban patients is focused mostly on MW bands corresponding to the major allergens Ara h 6 and Ara h 2.Conclusions Sensitization to peanut allergen is indeed relatively frequent in Cuba. The IgE profile is congruent to a sensitization pattern by ingestion of roasted peanuts and is directed to well-known major allergens.

Nymph and Adult Biology of Euschistus cornutus Dallas: a Potential Soybean Pest in the Neotropics.

Laboratory studies with Euschistus cornutus Dallas indicated that nymphs complete development when feeding on green bean, Phaseolus vulgaris L. pod, on soybean, Glycine max (L.) Merrill pod, and on raw shelled peanut, Arachis hypogaea L., but not on fruit (berry) of privet, Ligustrum lucidum Ait. Total mortality was lower on green bean pod (45%), and higher on soybean pod and peanut raw (75 and 80%, respectively). Nymph developmental time was significantly longer for females feeding on green bean pod (37.4days) than on soybean pod (27days); a single data was observed on peanut raw (32days). Males showed no significant differences in total nymph developmental time among foods (31.3 to 33.0days). At adult emergency, fresh body weight of females (52.2 to 68.5mg) and males (61.9 to 71.3mg) did not show statistical differences among foods tested nor between genders. Survivorship of E. cornutus adult after 50days was greater on peanut raw than on green bean or soybean pod; on privet berry, the majority of males and females (>80%) were dead after 20days. The reproductive performance data was, in general, greater on peanut raw than on green bean or soybean pod; on privet fruit, no female laid eggs. Fresh body weight gain occurred on all foods, except on privet berry, on which adults lost weight over time. Records of specimens from insect collections in Brazil indicated that E. cornutus occurs in the Southeast and South regions (19° to 31° S latitude). The most common host plant is soybean, suggesting a potential pest status of this stink bug on this crop in the future.

Development of immunoaffinity chromatographic method for Ara h 2 isolation

Ara h 2 is considered a major allergen in peanut. Due to the difficulty of separation, Ara h 2 had not been fully studied. Immunoaffinity chromatography (IAC) column can separate target protein with high selectivity, which made it possible to purify Ara h 2 from different samples. In this study, IAC method was developed to purify Ara h 2 and its effect was evaluated. By coupling polyclonal antibody (pAb) on CNBr-activated Sepharose 4B, the column for specific extraction was constructed. The coupling efficiency of the IAC column was higher than 90%, which made the capacity of column reached 0.56 mg per 0.15 g medium (dry weight). The recovery of Ara h 2 ranged from 93% to 100% for different concentrations of pure Ara h 2 solutions in 15 min. After using a column 10 times, about 88% of the column capacity remained. When applied to extract Ara h 2 from raw peanut protein extract and boiled peanut protein extract, the IAC column could recovery 94% and 88% target protein from the mixture. SDS-PAGE and Western blotting analysis confirmed the purified protein was Ara h 2, its purity reached about 90%. Significantly, the IAC column could capture dimer of Ara h 2, which made it feasible to prepared derivative of protein after processing.

Dissolution and fractionation of nut shells in ionic liquids

The aim of this work was to study the dissolution of raw peanut and chestnut shells in ionic liquids. Dissolution of raw biomass up to 7wt% was achieved under optimized operatory conditions. Quantification of polysaccharides dissolved through quantitative 13Cq NMR revealed extractions of the cellulosic material to ionic liquids as high as 87%. Regeneration experiments using an antisolvent mixture allowed to recover the cellulosic material and the ionic liquid. The overall mass balance presented very low loss rates (<8%), recoveries of 75% and 95% of cellulosic material from peanut and chestnut shells, respectively, and the recovery of more than 95% of the ionic liquid in both cases. These results show the high potential of using nut shells and ionic liquids for biorefining purposes. Moreover, high recovery of ionic liquids favors the process from an economical point of view.

Heat processing of peanut seed enhances the sensitization potential of the major peanut allergen Ara h 6

1ScopeProcessing of food has been shown to impact IgE binding and functionality of food allergens. In the present study, we investigated the impact of heat processing on the sensitization capacity of Ara h 6, a major peanut allergen and one of the most potent elicitors of the allergic reaction.2Methods and resultsPeanut extracts obtained from raw or heat‐processed peanut and some fractions thereof were biochemically and immunochemically characterized. These extracts/fractions, purified Ara h 6, or recombinant Ara h 6 including Ara h 6 mutants lacking disulfide bridges were used in in vitro digestion tests and mouse models of experimental sensitization. Peanut roasting led to the formation of complexes of high molecular weight, notably between Ara h 6 and Ara h 1, which supported the induction of IgE specific to native Ara h 6. On the contrary, a fraction containing free monomeric 2S albumins or purified native Ara h 6 displayed no intrinsic allergenicity. In addition to complex formation, heat denaturation and/or partial destabilization enhanced Ara h 6 immunogenicity and increased its sensitivity to digestion.3ConclusionThese results suggest that sensitization potency and IgE binding capacity can be supported by different structures, modified and/or produced during food processing in interaction with other food constituents.

Characterization of peanuts after dry roasting, oil roasting, and blister frying

Peanuts were systematically deep fried, blister fried, or dry roasted at 177 °C to Hunter L-values of 53.0 ± 1.0, 48.5 ± 1.0, and 43.0 ± 1.0, corresponding to light, medium, and dark roasting, respectively. Thermal modifications of the epidermal and parenchyma cells were observed in the scanning electron microscopic images for processed peanuts, compared to raw peanuts. Peanut microstructure was most extensively damaged by blister frying, followed by deep frying, and then dry roasting. The moisture content decreased with increased surface color, due to more moisture loss with longer heat processing time. For light roasting, blister fried peanuts had significantly higher moisture contents than the deep fried and dry roasted peanuts, while for medium and dark roasting, blister fried had lower moistures than the other two. Descriptive sensory analysis was able to distinguish the flavor and texture profiles of peanuts prepared by different roasting methods. In storage testing throughout 16 weeks, peroxide value measurements indicated the blister fried peanuts had the longest shelf life, followed by the dry roasted, and then the deep fried. Descriptive sensory analysis proved that the rate of the loss of roast peanut flavor during storage was faster in dry roasted peanuts followed by blister fried and deep fried.

Flavor of roasted peanuts (Arachis hypogaea) - Part I: Effect of raw material and processing technology on flavor, color and fatty acid composition of peanuts

Flavor and color of roasted peanuts have a strong impact on consumer acceptability. They can be influenced by raw material and processing technology. Raw peanuts of various market types, origins and grades were processed by different technologies to produce 134 unique samples, which were profiled by a sensory panel and analyzed for color and fatty acid composition. Principal Component Analysis, Canonical Variate Analysis and General Linear Model regression were used to identify differences in flavor, color and fatty acid profiles, and to relate them to raw materials or process conditions. Data showed that raw material selection is key for flavor, but processing is also significant. Specifically, maceration significantly increased “roasted peanut” and “dark roast” aromas, reducing “sweet”, “raw bean” aromas, and sweetness. It also influenced color and the fatty acid profile. Baking reduced “roasted peanut” and “dark roast” and increased “raw bean” aromas compared to frying, and impacted color development.

Occurrence of moulds inEgyptianprocessed peanut and control of aflatoxicfungi by some powder spices

Due to its high protein and lipid content, peanut are greatly appreciated by consumers but is very susceptible to aflatoxic fungi contamination indicates that there is a potential hazard of aflatoxins contamination in Egyptian processed peanuts and that requires resistance to this fungus. The current work aimed to study the occurrence of molds in peanut products as well as the antifungal properties of ten powder spices (Cloves, Black pepper , Cinnamon , Peppermint, Thyme , Cardamom , Cumin, Ginger, Onions and Fenugreek) at different concentration4,7,10 mg/ml in broth yeast extract sucrose media (YES) against aflatoxigenicAspergillusflavus fungi associated with peanut products. Samples(Row,Roasted,Roastedwith salted and with spices) were collected from five locations ( Cairo,Suez, Monofia of north Delta and Fayoum and Luxor of south Delta ) during one year from ( winter 2013 to autumn 2014). Four fungal genera were isolated Aspergillus( 8.30-38.97 %) , Penicillium ( 2.98 - 18.98 %), Fusarium (2.96 – 8.98%) and Rhizopus (0.98 – 11.95%) .Aspergillus section flavi was the most common. One way ANOVA indicated that there is significant among the five Governorates in their infection percentage of peanut by Aspergillus spp., but no significance difference in their infection percentage of peanut by Penicillium spp., Rhizopus spp. and Fusarium spp. Alsothe results revealed that A.flavus and A. parasiticus isolates produced aflatoxins.. It is noticed that clove powder is the most effective spice which completely inhibited A. flavusgrowth and aflatoxins production in broth media and in peanut seeds , while other spices only inhibit aflatoxins production at 10mg/ml but allow fungal growth at this concentrations ,but did not inhibit the fungal growth or aflatoxins production at4 and 7 mg/ml.It is noticed that the minimum inhibitory concentration ( MIC) of clove was at 3mg/ml. As well as the effect of spices ( clove ,cinnamon,thyme and peppermint) on A. flavus in raw peanut seeds showed that the fungal growth was noticed at all the concentrations (4,7 and 10 mg/g) but it was weak at 10mg/g of clove. Aflatoxinsproduction were inhibited at 10mg/g spices( clove ,cinnamon, thyme and peppermint as well as at 7mg/g clove and cinnamon inhibit aflatoxins production. On the other hand at 7mg/g of peppermint and thyme reduced the aflatoxinsproduction till 22.3 and 30μg/kg respectively. At 4ml/g of spices concentration( clove, cinnamon, peppermint and thyme) aflatoxins production were reduced to 20, 30, 43.8 and 50 μg/kg respectively in peanuts for 7 days.

Flavor of roasted peanuts (Arachis hypogaea) — Part II: Correlation of volatile compounds to sensory characteristics

Flavor and color of roasted peanuts are important research areas due to their significant influence on consumer preference. The aim of the present study was to explore correlations between sensory attributes of peanuts, volatile headspace compounds and color parameters. Different raw peanuts were selected to be representative of common market types, varieties, growing locations and grades used in Europe. Peanuts were roasted by a variety of processing technologies, resulting in 134 unique samples, which were analyzed for color, volatile composition and flavor profile by expert panel. Several headspace volatile compounds which positively or negatively correlated to “roasted peanut”, “raw bean”, “dark roast” and “sweet” attributes were identified. Results demonstrated that the correlation of CIELAB color parameters with roast related aromas, often taken for granted by the industry, is not strong when samples of different raw materials are subjected to different processing conditions.

Samango Monkeys (Cercopithecus albogularis labiatus) Manage Risk in a Highly Seasonal, Human-Modified Landscape in Amathole Mountains, South Africa

Wild species use habitats that vary in risk across space and time. This risk can derive from natural predators and also from direct and indirect human pressures. A starving forager will often take risks that a less hungry forager would not. At a highly seasonal and human-modified site, we predicted that arboreal samango monkeys (Cercopithecus albogularis labiatus) would show highly flexible, responsive, risk-sensitive foraging. We first determined how monkeys use horizontal and vertical space across seasons to evaluate if high-risk decisions (use of gardens and ground) changed with season, a proxy for starvation risk. Then, during a subsequent winter, we offered equal feeding opportunities (in the form of high-value, raw peanuts) in both gardens and forest to see if this short-term change in food availability and starvation risk affected monkeys’ foraging decisions. We found that during the food-scarce winter, monkeys foraged outside indigenous forest and in gardens, where they fed on exotic species, especially fallen acorns (Quercus spp.), despite potential threats from humans. Nevertheless, and as predicted, when given the choice of foraging on high-value foods in gardens vs. forest during our artificial foraging experiment, monkeys showed a preference for a safer forest habitat. Our experiment also indicated monkeys’ sensitivity to risk in the lower vertical strata of both habitats, despite their previous extensive use of the ground. Our findings support one of the central tenets of optimal foraging theory: that risk of starvation and sensitivity to the variation in food availability can be as important drivers of behavior as risk of predation.

Exposure assessment of aflatoxins in Thai peanut consumption

Aflatoxins (AFs) and aflatoxin B1 (AFB1) intake through consumption of peanuts and peanut products were estimated from 60 samples. The samples were collected from 2 retail and 2 wholesale markets in Bangkok during November 2013–January 2014. The results showed that 80% of raw peanut samples were contaminated with AFs while 100% of roasted and ground peanuts samples were contaminated. The highest concentration of AFs was found in ground peanuts at 362.48 ng g−1 resulting in the highest mean concentration (68.22 ng g−1). According to a food consumption database, the average intake of AFs was estimated at 0.49, 0.40 and 2.13 ng/kg bw/day for raw, roasted and ground peanuts, respectively. The potential risk for cancer was estimated at 0.01–0.12 cancer/year/100,000 persons. The results suggest that the current situation of aflatoxins contamination in peanuts and peanut products (especially in ground peanuts) has an adverse effect on the health of the Thai population.

Quantitative Proteomic Profiling of Peanut Allergens in Food Ingredients Used for Oral Food Challenges.

Profiling allergens in complex food ingredients used in oral food challenges and immunotherapy is crucial for regulatory acceptance. Mass spectrometry based analysis employing data-independent acquisition coupled with ion mobility mass spectrometry-mass spectrometry (DIA-IM-MS) was used to investigate the allergen composition of raw peanuts and roasted peanut flour ingredients used in challenge meals. This comprehensive qualitative and quantitative analysis using label-free approaches identified and quantified 123 unique protein accessions. Semiquantitative analysis indicated that allergens Ara h 1 and Ara h 3 were the most abundant proteins and present in approximately equal amounts and were extracted in reduced amounts from roasted peanut flours. The clinically significant allergens Ara h 2 and 6 were less abundant, but relative quantification was unaffected by roasting. Ara h 5 was undetectable in any peanut sample, while the Bet v 1 homologue Ara h 8 and the lipid transfer protein allergen, Ara h 9, were detected in low abundance. The oleosin allergens, Ara h 10 and 11, were moderately abundant in the raw peanuts but were 100-fold less abundant in the defatted roasted peanut flour than the major allergens Ara h 1, 3, 2, and 6. Certain isoforms of the major allergens dominated the profile. The relative quantitation of the major peanut allergens showed little variation between different batches of roasted peanut flour. These data will support future development of targeted approaches for absolute quantification of peanut allergens which can be applied to both food ingredients used in clinical studies and extracts used for skin testing and to identify trace levels of allergens in foods.

Extended boiling of peanut progressively reduces IgE allergenicity while retaining T cell reactivity

Current peanut oral immunotherapy is hampered by frequent adverse events. It has been shown that boiling can reduce peanut allergenicity. Hypoallergenic peanut products have the potential to reduce treatment-related reactions during desensitization. To show that extended boiling (for up to 12 h) can progressively reduce peanut allergenicity while retaining T cell reactivity. Raw peanuts were boiled for half, 1, 2, 4 and 12 h in deionized water. After dehydration, boiled and raw peanuts were ground, defatted and soluble proteins extracted in PBS and cooking water (leachate) retained. SDS-PAGE, Western blot, inhibition ELISA, mass spectrometry and skin prick test were used to characterize changes to peanut allergens and human IgE reactivity. T cell responses to raw and boiled peanut extracts were determined by proliferation of CD4+/CD25+/CD134+ T cells in peanut-allergic and non-allergic individuals. Extended boiling progressively reduced peanut allergenicity through a combination of leaching of allergens into cooking water, fragmentation of allergens and denaturation of conformational epitopes. Two-hour boiling led to an eightfold reduction in IgE binding capacity of boiled peanuts as determined by inhibition ELISA, while 12-h boiling led to a 19-fold reduction. Mass spectrometry revealed an increasing number of unique allergen peptides with longer boiling times. Raw, 2- and 12-h boiled peanut extracts were equivalent in their ability to stimulate T cell activation and proliferation. Progressive reduction in peanut allergenicity with extended boiling does not affect T cell reactivity. Boiled peanuts may be a candidate for oral immunotherapy.

Occurrence and factors associated with aflatoxin contamination of raw peanuts from Lusaka district's markets, Zambia

Peanuts, one of the most susceptible crops to aflatoxin (AF) contamination, are widely produced and consumed in Zambia. This cross-sectional study was designed to determine the levels of AFs in raw peanuts sold in Lusaka district's markets as well as identify factors associated with increased AF presence. Raw peanut samples were collected from open markets and supermarkets and analyzed for aflatoxin contamination using high performance liquid chromatography (HPLC). A questionnaire was also administered to the peanut vendors to investigate factors contributing to increased levels of AFs in peanuts. Of the 92 samples, 51 (55.4%; 95% CI: 44.9–65.4) tested positive for presence of AFs. The overall median and geometric mean ± standard deviation (SD) concentration for AF were 0.23 ppb (range: 0.014–48.67 ppb) and 0.43 ± 9.77 ppb, respectively. The association between market types and presence of AFs was not statistically significant (Pearson Χ2 = 0.0587, p = 0.809). Of 51 samples that tested positive to AF, 6.5% and 12% were above the maximum permissible limits (MPLs) set by the Codex Alimentarius Commission and European Union standards, respectively. There was a significant difference in the levels of AF between Chalimbana and Kadononga (p<0.0001), and also Chalimbana and Makulu red (p<0.0001). Chalimbana was the most at risk of AF contamination, when compared to other peanut varieties. The high level of AFs in raw peanuts from both supermarkets and open markets samples constitutes a health hazard for the population of Lusaka district. Therefore, intervention strategies that reduce the levels of AF contamination in peanuts should be given priority.