Flour Samples Research Articles

Rapid estimation of DON content in wheat flour using close‐range hyperspectral imaging and machine learning

AbstractFusarium head blight (FHB) is one of the most destructive fungal diseases affecting wheat (Triticum aestivum). Moreover, it is notorious for producing mycotoxin deoxynivalenol (DON), posing a significant global threat to food and feed safety. Traditional methods like enzyme‐linked immunosorbent assay (ELISA) and gas chromatography‐mass spectrometry (GC‐MS) are commonly used to assess DON levels in grain or flour samples and are time‐consuming and expensive. Therefore, a faster, cost‐effective method to estimate DON content is needed, especially for enhancing breeding efforts to reduce DON levels in wheat. In this study, we envisioned integrating close‐range hyperspectral imaging with deep learning (DL) models to estimate DON content in wheat meal/flour. We selected 243 advanced breeding lines from the South Dakota State University (SDSU) wheat breeding program that were evaluated in FHB nurseries (2019–2020 and 2020–2021). The wheat meal samples were analyzed for DON content using GC‐MS and subsequently subjected to close‐range hyperspectral imaging. We evaluated three conventional machine learning (ML), two DL models and data augmentation. Among the conventional ML models, partial least squares regression (PLSR) (with R2P = 0.88 and 0.90 for original and augmented datasets, respectively) demonstrated the highest prediction accuracies for DON content. However, the one‐dimensional convolutional neural network (1D‐CNN) achieved the highest prediction accuracies (R2P = 0.90 and = 0.96 for original and augmented datasets, respectively) compared to all tested models and demonstrated the lowest error. In conclusion, integration of advanced hyperspectral imaging with ML approaches exhibits significant potential for high‐throughput and cost‐effective estimation of DON content in wheat, thereby accelerating wheat breeding efforts for reduced DON levels.

Impact of Tuber Section, Steeping Solution, and Concentration on Physicochemical Properties of Yam (Dioscorea rotundata) Flour

This study examined various factors such as Tuber Cutting (TC), Tuber Processing Method and Duration (TPM and TPD), Soaking Solution Type and Concentration (SST and SSC), as well as Parameter Analytical Temperature (PAT) on flour samples prepared from different parts of yam tubers.

Changes in Nutritional and Techno-Functional Properties of Whole Grain Maize Flours Induced by Dry-Heat Treatment.

The present study was carried out to demonstrate the effects of dry heat treatment (DHT) at different temperatures (100, 125, 135, 150, and 165 °C) on the nutritional and techno-functional properties of white, blue, and yellow whole grain maize flour. Results showed that DHT increased the insoluble dietary fiber and free phenolic compounds of the investigated maize flours, while the bound phenolic compounds, anthocyanins, and pasting properties decreased with the rising of the applied temperature. The application of DHT caused the most notable changes regarding the amount of dietary fiber. Content of NDF (neutral detergent fiber) ranged from 11.48% to 44.35%, 14.19% to 37.84%, and 15.15% to 45.86% in white, yellow, and blue maize samples, respectively. Furthermore, at the highest temperature applied in the DHT (165 °C) the content of soluble free phenolic compounds in yellow and blue maize flour samples was 1.2- and 1.4-fold higher compared to control flour samples. DHT significantly improved the functionality of maize flour in terms of water absorption capacity, water solubility, and digestibility, thus it can be effectively used to make up for the poor functionality of raw maize flour. This study shows that DHT at moderate temperatures (125-135 °C), could be a viable solution for the pre-processing of maize flour to enhance the potential for its utilization in the food industry.

Health risk assessment of lead and cadmium exposure from food and snuff in Pakistani population

BackgroundSmokeless tobacco (SLT) is a tobacco-based product consumed without burning or smoking. Snuff, commonly known as naswar, is a widely used SLT product in Pakistan. This study is designed to investigate the concentrations of lead (Pb) and cadmium (Cd) in snuff and their associated health risks to consumers. MethodsBlood samples from snuff consumers and non-consumers were analyzed for Pb and Cd concentrations. Additionally, samples of drinking water and wheat flour were also analyzed for Pb and Cd. Health risk assessments were calculated using hazard quotient (HQ) and incremental lifetime cancer risk (ILCR) for Pb and Cd. ResultsSnuff consumers had significantly higher blood-Pb and blood-Cd levels compared to non-consumers. Approximately 38.5 % of snuff consumers were found to exceed blood-Pb levels from the safe limits (10 µg dL⁻¹) of the World Health Organization (WHO), while 48.9 % of snuff consumers were found to exceed blood-Cd levels from the WHO safe range of 0.03–0.12 µg dL⁻¹. Snuff samples contained Pb and Cd concentrations ranging from 5.3 to 22.4 µg g⁻¹ and 0.5–2.2 µg g⁻¹, respectively. Drinking water and wheat flour samples were found within the safe limits for Pb and Cd concentration, suggesting snuff as the primary source of exposure. Health risk assessments indicated elevated HQ values, for Pb (38.9 %) and Cd (14.3 %) detected in snuff, surpassing the safe HQ threshold of 1. Concerning ILCR from snuff, values for Pb were within the acceptable range, but alarmingly 100 % of samples for Cd exceeded the safe limits of USEPA (1.0×10⁻⁴), indicating a significant cancer risk in snuff users. ConclusionThis study highlights the exceeded Pb and Cd concentrations in snuff as well as also reporting significant carcinogenic and non-carcinogenic health risks to consumers. These findings emphasized the urgent need for regulatory bodies to ensure the safety of snuff before selling in the market. Public Health Professionals should also initiate educational campaigns to raise awareness among consumers and manufacturers about various health risks associated with the snuff.

Factors Affecting the Adhesion of Flour Particles to Stainless-steel Surfaces and Vacuum Dry-cleaning

Recent outbreaks and recalls linked to flour-based products have highlighted the need for improved cleaning methods in low-moisture environments. The factors affecting adhesion forces of flour particles, and the vacuum cleaning methodologies to overcome these forces, need to be better understood. The objectives of this study were to: (1) Measure electrostatic charge build-up in flour under different environmental conditions (20, 40, 60% relative humidity at room temperature), (2) quantify how powder size (US standard No. 60–80 or 80–100 mesh), electrostatic charge (charged and uncharged), and relative humidity impact the force required to remove the powder from an electropolished 304 stainless steel coupon (8 × 8 × 0.2 cm), and (3) determine the most effective vacuum nozzle angle (0, 45, 90° relative to the surface) for cleaning. Chargeability (nC) of flour samples was assessed using Faraday cup electrometry, while the surface adhesion force of the flour particles was measured using a custom-built impact tester. The surface cleanliness after vacuum treatments was assessed using ATP (adenosine triphosphate) swabs and a luminometer. Charged flour samples at 20% relative humidity (RH) exhibited a significantly higher charge compared to those at 40 and 60% RH. Within the 60–80 mesh range, charged flour showed higher adhesion rates than uncharged samples at both 20 and 40% RH. However, in the 80–100 mesh range, charged flour did not show a significant difference in adhesion when compared to uncharged samples at any RH level. Additionally, at 60% RH, surface residues measured by ATP were significantly lower for a vacuum angle of 90° than for 0° across both 60–80 mesh and 80–100 mesh size ranges of wheat flour. The vacuum cleaning treatment proved capable of overcoming the increase in adhesion from triboelectric forces; however, trace flour residues were still detected on stainless steel surfaces postvacuuming, indicating that vacuuming alone may be insufficient.

Determination of the Iron and Zinc Contents for Teff Types in The NorthWestern Part of Ethiopia

A simple and efficient method was used to determine the levels of iron and zinc in the teff flour samples. The aim of this study was to determine the concentration levels of iron and zinc in teff samples across different locations and to compare with other reported values due to different agricultural applications. The levels of Fe and Zn in the three types of teff samples collected from the three sampling areas were determined by using Micro-plasma atomic emission spectroscopy. The iron mean concentration of white teff was highest in the Bure site followed by Bahir Dar and Debre Markos sampling sites. The level of iron in the red teff was highest in the Debre Markos site followed by Bure and Bahir Dar sampling sites respectively. Similarly, the iron content of the mixed teff was highest in Bahir Dar site followed by Debre Markos and Bure sampling sites. However, the amounts of Zn determined in the three types of teff samples collected from the three different locations were almost similar. The overall mean concentrations determined (mg/kg, air dry weight) for the teff samples collected from the Bure, Debre Markos and Bahir Dar sites were in the ranges of Fe (719) > Zn (86) >, Fe (728) > Zn (87) and Fe (668) > Zn (73), respectively. The one way ANOVA indicated the mean concentrations of the two studied metals found in the three types of teff samples within and between the sampling sites was not significant at 95% confidence level.

Evaluation of the influence of temperature and time exposure on Peruvian Maca (Lepidium meyenii) flour samples through NIR spectroscopy and chemometrics

In this study, the three most known varieties of the Peruvian Maca (Lepidium meyenii), yellow, red, and black, were fractionated in multiple sub-samples and submitted to heating (from 25 to 200 °C) during one hour at 10-minute intervals to be measured using the near-infrared (NIR) spectroscopy after 24 h resting in a desiccator. The study focused on changes related to heating for considering new applications on Maca-enriched food products such as bread, cakes, and cookies, which are prepared over high temperatures during different time exposures. To perform the experiment, 9 portions of 1 g of each sample remained in an oven at each temperature (25, 50, 100, 150, 160, 170, 180, 190, and 200 °C) for different times (10, 20, 30, 40, 50, and 60 min). The principal component analysis (PCA) and the multivariate curve resolution with alternating least squares (MCR-ALS) were applied to interpret the results. In general, it was observed that spectral variations start to occur from heating samples from above 100 °C. The recovered signals indicated that most spectral variations occurred in regions assigned to NH vibrations, suggesting that heating influences the protein and/or macamides structures, which are responsible for most of the properties attributed to the Peruvian Maca. The yellow Maca phenotype was the most susceptible to spectral variations after heating, while the black Maca displayed the slowest spectral transformations. This study may encourage deeper investigations into the use of Maca-derived foods regarding their health-beneficial effects after heating to indicate the limitations of Maca applications.

Phytochemical analysis and GC-MS based bioactive compounds determination of 60 days Nigerian Vigna Radiata aqueous root extract

In the present study, the sturdy root of Nigerian Vigna radiata (L.) commonly called mung bean was investigated for the phytochemical content. This was necessitated as a result of limited information observed on the phytochemical content of fully matured Nigerian Vigna radiata root. 60 days old Vigna radiata (L.) plant, a newly introduced crop in Nigeria, was harvested from the farm of National Biotechnology and Research Development Agency, Abagana Centre, Nigeria. The roots were neatly separated from the plant, rinsed well with distilled water, air dried and grounded into flour. The 60 days old Nigerian Vigna radiata root flour sample (NVrR) subjected to preliminary phytochemical assay revealed the presence of 12 bioactive compounds with a remarkable high percentage concentration of 26.780% recorded for flavonoids content. Tannins also recorded appreciable value of 8.927% while values < 5% were noted for the remaining compounds. Further confirmation of the actual bioactive compounds present in 60 days old NVrR through GC-MS studies, generated 30 observable peaks with 28 bioactive compounds identified through spectrum matching with MassHunter\Library\NIST14.L spectral database. The major component, eluted at RT 23.565 (peak area 33.38%) revealed a bioactive compound which has been reported as an active ingredient in the production of detergents and biodiesel. This discovery represents a groundbreaking innovation in the utilization of NVrR for the production of briquettes, offering a cost-effective alternative energy source. Isolation of the identified compounds may prove the NVrR an important raw material for industrial productions.

First evidence on the occurrence of multi-mycotoxins and dietary risk exposure to AFB1 along the cassava value chain in Uganda

This study investigated the occurrence and distribution of multiple mycotoxins (aflatoxin B1, B2, G1, G2, fumonisins B1, B2, ochratoxin A (OTA), deoxynivalenol (DON), zearalenone (ZEN), and citrinin (CIT)) in cassava products and as assessed the potential risk of aflatoxin B1 (AFB1) exposure among cassava consumers. A total of 192 samples of cassava products (96 flour and 96 chips, each with 48 samples from farmer and 48 from wholesaler) were analysed using LC/MS–MS. All positive samples irrespective of their origin (flour or chips) exhibited AFB1 levels exceeding the EU regulatory threshold of 5 µg/kg. The sum of fumonisins (FB1 + FB2), ZEN, and DON were significantly (P < 0.05) higher in cassava flour (14.3 µg/kg; 3.71 µg/kg; 25.1 µg/kg) compared to chips (6.54 µg/kg; 1.25 µg/kg; 0.25 µg/kg), respectively. Aflatoxins G2 was not detected in any of 192 samples. Cassava flour samples from farmers exhibited significantly (P < 0.05) higher mean concentrations of AFB1 (27.1 µg/kg), total aflatoxins (78.2 µg/kg), and ochratoxin A (79.6 µg/kg) in contrast to wholesalers, whose mean levels were notably lower at 8.91, 5.79 µg/kg, and 2.44 µg/kg, respectively, pointing the likely critical source of mycotoxin contamination. Cassava consumers in Northern Uganda are at a higher risk, with an estimated 2.06 cancer cases per 100,000 individuals per year compared to those in Eastern Uganda at 0.25. This study underscores the urgent need for interventions to manage aflatoxins in cassava flour, particularly at farm level in Northern Uganda. It accentuates a shift market to household-level sampling and the need for analytical methods targeting multiple mycotoxins.

Fusarium species and assessments of mycotoxin (deoxynivalenol), in wheat seeds from different regions of Türkiye

Wheat cultivation is important in Turkish agriculture, which ranks 10th among international wheat producers, and is an important wheat exporter, particularly to Europe. Fusarium-related threats, such as Fusarium Head Blight (FHB) and Fusarium Crown and Root Rots (FCR, FRR), and related mycotoxin seed contamination, jeopardize product quality. This study analysed 65 wheat seed samples for presence of Fusarium species, from cultivars of Triticum aestivum (bread wheat) and T. durum (durum wheat) collected from seven regions of Türkiye. PCR with specific primers, and phylogenetic analyses of TEF1-α segments, discriminated Fusarium species. Levels of the mycotoxin deoxynivalenol (DON) in flour samples were also evaluated. Out of 195 Fusarium isolates, the prominent species included F. graminearum (32% of isolates), F. proliferatum (16%), F. avenaceum (11%), F. clavum (11%), and F. verticillioides (7%). Less frequently isolated species were F. oxysporum (6%), F. acuminatum (3%), F. ramigenum (3%), F. culmorum (3%), F. poae (2%), F. sambucinum (2%), F. tricinctum (2%), Fusarium sp. FTSC12 (2%), F. andiyazi (1%), and F. equiseti, F. incarnatum, and F. fasciculatum (each 0.5%). Five of the 65 samples tested positive for DON, with two exceeding the European Commission threshold for mycotoxin contamination; one bread wheat from the Black Sea region, known for its annual rainfall, and a durum wheat sample from southeastern Anatolia, which had the highest detected DON level of 1730 μg kg-1. Among these samples F. graminearum was the predominant species. As F. andiyazi and F. ramigenum are not normally associated with wheat plants, a pathogenicity test was conducted with two isolates of each of these species, revealing no pathogenicity on the durum wheat cultivar ‘San Carlo’. These results provide a basis for managing fungal threats and mycotoxin contamination, safeguarding the quality of wheat grain as an essential agricultural product.

SELECTION OF LACTIC ACID BACTERIA FOR RYE BREAD SOURDOUGH

Lactic acid bacteria are widely used to produce diverse type of fermented products. One of conventional applications for lactic acid bacteria is inclusion into sourdough for bread baking. These microorganisms play a key role in dough fermentation of rye flour or wheat and rye mixture since the yield of stable and well-leavened rye dough is possible only in acidic environment. Lately, despite the development of accelerated baking technologies and technological improvements, which in some cases eliminate the need for sourdough, interest in the tradition of making bread using sourdough as a source of flavoring, nutrient and health-enhancing compounds is constantly growing across the globe. It is natural therefore that focus of the researchers is centered on seeking new strains of lactic acid bacteria attractive as potential constituents of rye bread sourdough. Screening of strains-candidates to be included in the consortia for rye flour fermentation was conducted among collection cultures (23 strains), isolates from rye flour samples (154 strains) and among craft rye dough cultures for spontaneous fermentation kindly provided by private households of Minsk, Turov, Zhitkovichi (21 strains). Identification of lactic acid bacteria following examination of morphological, cultural, physiological and biochemical characteristics of the cultures and guided by the data of MALDI TOF mass spectrometry indicated that the compared microorganisms represented genera Lactiplantibacillus, Limosilactobacillus, Pediococcus, Weissella, Lactococcus. The majority of lactic acid bacteria isolated from rye flour samples belonged to genera Lactiplantibacillus and Pediococcus. Representatives of genera Lactiplantibacillus and Levilactobacillus prevailed among domestic variants of rye bread sourdoughs. Evaluation of acidogenic capacity of analyzed cultures upon 16 h fermentation in water-flour suspension by Neumann technique and organoleptic assessment of the obtained solutions sorted out for further studies 10 strains of lactic acid bacteria referred to species Levilactobacillus brevis (4 strains) Lactiplantibacillus plantarum (3 strains) and singular strains of species Lactiplantibacillus paraplantarum, Limosilactobacillus fermentum, Weissella cibaria. Glycosyl-hydrolases produced by lactic acid bacteria constituting starter cultures largely determine biochemical processes during fermentation of flour mixtures. Chromogenic substrates o-nitrophenyl-β-D-galactopyranoside, o-nitrophenyl-α-D-galactopyranoside, 4-nitrophenyl-β-D-glucopyranoside were used in 1 mmol concentration to assay activities of β-galactosidase, α-galactosidase, β-glucosidase, respectively. It was found that all tested bacteria of species Levilactobacillus brevis and Limosilactobacillus fermentum were characterized by synthesis of proteins with α-galactosidase and β-galactosidase activities in the course of growth on media with glucose and maltose. β-glucosidase activity was revealed in all representatives of species Lactiplantibacillus plantarum, Levilactobacillus brevis and Lactiplantibacillus paraplantarum. Amylolytic activity was detected in two Lactiplantibacillus plantarum strains, whereas bacteria of species Weissella cibaria displayed a weak β-glucosidase activity. An important criterion to select microbial constituents for dough fermentation is antagonistic activity toward contaminating microbiota. Antagonistic response of lactic acid bacterial cultures to causal agents of bread spoilage was demonstrated, including epidemiologically significant fungi of genera Fusarium, Aspergillus, Penicillium, etc. Analysis of obtained data has enabled to compose microbial consortia promising for further elaboration of technologies for producing active bread-making starter formulas with upgraded biotechnological properties and enhanced alimentary, nutritional and biological value.

Changes to Structural and Compositional Features of Water-Soluble Arabinoxylans in Sourdough Bread.

This research investigates the influence of milling methods and starter cultures on the structural characteristics of water-extractable arabinoxylans (WE-AX) in stone-milled whole-grain flour and sourdough bread. Stone milling was conducted to generate six different whole wheat flour samples, from which sourdough bread was produced using wheat and rye starter cultures. The study found that both milling parameters and the type of starter culture significantly impacted the fine structural details of WE-AX, including sugar composition, arabinoxylan (AX) content, and the arabinose-to-xylose (A/X) ratio values. These differences were statistically significant (p < 0.05). Furthermore, transforming flour into sourdough bread resulted in the molecular degradation of AX, significantly reducing its molecular weight and leading to a more heterogeneous fine structure. This detailed characterization of AX's alterations during food processing provides insights into evaluating its potential health benefits in whole-grain products.

Nutritional and Microbial Quality of Locally Processed Plantain Flour

Flour is a fibre rich in carbohydrate but the preparation and packaging process are exposed to microbial contaminations and nutritional alterations. This study was therefore undertaken to evaluate the microbial and nutritional quality of packaged and unpackaged plantain flour. Cultural, microscopic, biochemical test and most probable number (MPN) methods were employed to determine the various microorganisms; while pproximate analysis was done to estimate inherent nutrients in the flour. Significant differences between packaging, nutritional and microbial qualities were determined using ANOVA or T-test, at P&lt;0.05. Results show Heterotrophic bacterial count in packaged plantain flour was 4.52 ± 1.20 x 102 Cfu/g and unpackaged flour 6.01 ± 1.43 x 102 Cfu/g. Coliform bacterial count in plantain flour showed packaged 2.77 ± 2.01 x 102 Cfu/g and unpacked 3,45 ± 0.50 x 102 Cfu/g. The Pseudomonas count showed the packaged plantain flour count of 3.24 ± 0.60 x 102 Cfu/g and the unpackaged 4.31 ± 1.23 x 102 Cfu/g. The proximate analysis of the flour sample revealed an increase in nutritional contents. This study concludes that exposure of flour to the environment increases microbial content and therefore health and hygiene concerns.

Determination of azodicarbonamide in flour samples using high-performance liquid chromatography–tandem mass spectrometry with xanthydrol pre-column derivatisation

Azodicarbonamide (ADA) is approved as a food additive in flour products due to its oxidising and bleaching properties. However, it is prohibited in Australia and Europe on account of its toxicity and the risk of causing asthma in humans. A method was developed to determine ADA in actual flour samples. This work presents an optimised methodology based on derivatisation and clean-up procedures followed by ultra-performance liquid chromatography coupled with electrospray ionisation tandem mass spectrometry (UPLC–ESI-MS/MS). The analytical method was successfully validated. An excellent result was obtained for the linearity of matrix-matched calibration curves (R 2 > 0.99) in the concentration range of 0.10–80 mg/kg. The recovery rate varied from 81.7% to 102.3%. The relative standard deviations (RSDs) of repeatability (n = 6) were 1.3–4.1%, and inter-day RSDs (n = 6) were 2.2–4.8%. The limit of detection and the limit of quantification were 0.014 and 0.042 mg/kg, which were significantly lower than the requirement of 45 mg/kg stipulated in the Chinese National Food Safety Standard (GB 2760-2014). The detection rate of ADA in 26 flour samples was 23.1%, with the concentration ranging from 0.023 to 23.2 mg/kg.

Impact of variety and drying methods on the physicochemical, functional, and thermal properties of Ethiopian potato (Plectranthus edulis) tuber flour

This study aimed to analyse the physicochemical, structural, functional, and thermal properties of flour from two indigenous Ethiopian Potato (Plectranthus edulis) varieties, Chanqua and Loffo, and to compare with wheat flour (WF). The study also investigated how oven and sun drying methods affected the physicochemical properties of the flours. The results demonstrated a significant distinction (p ≤ 0.05) between the flour samples and WF, attributable to variations in both the varieties and the drying methods except that no significant difference in pH was observed due to the varieties, and the fibre and ash content did not vary significantly with the drying methods. The moisture content (MC) of the flours ranged from 5.72 % in oven-dried Chanqua Ethiopian potato flour (OD-CEPF) to 7.53 % in sun-dried Loffo Ethiopian potato flour (SD-LEPF), both of which were lower compared to WF. The protein content varied from 4.47 % (SD-CEPF) to 5.93 % (OD-LEPF). FTIR tests revealed a significant impact on the structural changes, leading to variations in the location and intensity of infrared absorption peaks, particularly in sensitive regions. Whereas, the XRD patterns showed characteristic B-type diffraction, with a relative crystallinity (RC) of 31.97 % in CEPF and 30.53 % in LEPF having a significant difference (p ≤ 0.05) between them. LEPF had better flow properties than CEPF, with lower Hausner ratio (HR) (1.16 vs. 1.25), Carr's index (CI) (14.51 % vs. 20.26 %), and angle of repose (31.00° vs. 34.67°). It also showed significantly higher (p ≤ 0.05) water absorption capacity (WAC), oil absorption capacity (OAC) and swelling power (SP) properties than CEPF. The study also indicated notable distinctions in the thermal and paring properties of flours. The oven drying method was found to be superior in enhancing the physicochemical properties, with LEPF showing better physicochemical, functional, structural, and thermal properties than CEPF.

Aflatoxin B1 contamination in porridge formulations for children and ingredients sourced from selected markets in Rwanda

Providing safe and nutritious food for children globally is a challenge. In Rwanda, an initiative was introduced in 2018 to tackle chronic malnutrition by offering fortified porridge flour to economically disadvantaged families during critical periods. However, flour-based products in the sub-region have caused public health concerns following aflatoxin B1 (AFB1) contamination. This study analyzed the levels of AFB1 in 197 porridge formulations from health centers, and 248 samples of porridge ingredients from open markets in three districts of Rwanda. Samples were collected between June 2021 and December 2022 and analyzed using ultra-high-performance liquid chromatography. Of the 197 samples from health centers, 97.9 and 89.8% exceeded the European Union maximum limits for baby foods and foods for special medical purposes (0.1 μg/kg), and cereals and nuts (2 μg/kg), respectively with an average contamination level of 2.77 μg/kg (±0.98). Only four samples exceeded the East African Community maximum limits of 5 μg/kg for AFB1. Samples from open markets that exceeded the European Union and East African community limits of 0.1 μg/kg, 2 μg/kg, and 5 μg/kg ranged from 17 to 100%, 0 to 100%, and 0 to 100%, respectively. Site and processing significantly influenced levels of AFB1 contamination in open-market samples. The mean AFB1 levels were 17.85 μg/kg (±70.25) in Burera District, 36.04 μg/kg (±85.59) in Huye District, and 9.01 μg/kg (±18.49) in Nyarugenge District. The average AFB1 levels significantly varied between different products. Peanut samples showed higher contamination levels of 56.79 and 99.08 μg/kg for grain and flour, respectively. Flour samples in general had a higher mean of 51.65 μg/kg (±105.75), compared to grain samples, 16.5 μg/kg (±44). Thus, there are potential health risks associated with chronic exposure to AFB1 in children consuming flour-based foods from health centers and open markets. Interventions to mitigate AFB1 contamination and protect children should focus on food processing practices, implementing strict quality control measures, and raising awareness among stakeholders about the risks of AFB1 in flour-based products provided to children in Rwanda and similar settings. Key words: Flour-based porridge, contamination, aflatoxin B1, children, Rwanda

Change in volatile profiles of wheat flour during maturation

The volatile profiles of wheat flour during maturation were examined through headspace solid-phase micro-extraction gas chromatography-mass spectrometry (HS-SPME-GC/MS) combined with electronic nose (E-nose) and electronic tongue (E-tongue) analyses. The wheat flour underwent maturation under three distinct conditions for predetermined durations. While GC/MS coupled with E-tongue exhibited discernment capability among wheat flour samples subjected to varying maturation conditions, E-nose analysis solely relying on principal component analysis failed to achieve discrimination. 83 volatile compounds were identified in wheat flour, with the highest abundance observed in samples matured for 50 d at 25 °C. Notably, trans-2-Nonenal, decanal, and nonanal were the main contributors to the characteristic flavor profile of wheat flour. Integration of HS-SPME-GC/MS with E-tongue indicated superior flavor development and practical viability in wheat flour matured for 50 d at 25 °C. This study furnishes a theoretical groundwork for enhancing the flavor profiles of wheat flour and its derivative products.

Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers for vortexed assisted dispersive µ-solid-phase extraction of organophosphorus pesticides in baby food cereal, rice and wheat flour

Food safety is an important issue to protect humane health and improve the life quality. Hence, analysis of the possible contaminants in food samples is essential. A rapid and efficient vortexed-assisted dispersive µ-solid-phase extraction coupled with gas chromatography-mass spectrometry was proposed for simultaneous separation/preconcentration and determination of five commonly used organophosphorus pesticides. Reduced graphene oxide decorated NiCo2(OH)6 nanoflowers as a novel nanostructure was synthetized and introduced for separation of the target pesticides from the wheat flour, rice flour, and baby food cereal samples. The characterization of the nanoflowers was accomplished by SEM-EDX, XRD, and FT-IR techniques. The main factors including pH, the amount of nanoflower, the volume of sample solution, salt concentration (ionic strength), desorption conditions (i.e. desorption solvent type and volume, and desorption time) on the pesticides extraction efficiencies were inquired using matrixed match method. Applying the optimum conditions, the linearity of 0.100–500.000 µg kg−1, LODs and LOQs in the range of 0.03–0.04 µg kg−1 and 0.1 µg kg−1 for the studied food samples were obtained. The repeatability (intra–day precision (n = 5)) of ≤ 2.0 % and reproducibility (inter–day precision, days = 5, n = 3) of ≤3.1 % and were appraise at three concentration levels (10, 50 and 100 μg kg−1 of each analyte). High relative recoveries of 90.0–99.3 % ascertained high potential of the presented method for complex matrix analysis.

Effect of packaging and storage conditions on the pasting and functional properties of pretreated yellow-fleshed cassava flour

Cassava is highly susceptible to post harvest physiological deterioration which makes it necessary to initiate processing so as to extend the shelf life. In order to improve and enhance the nutritional characteristics of the processed cassava flour, this research was carried out so as to evaluate the adequate packaging materials and storage conditions necessary for safe storage and good flour quality. Pasting properties of food/flour is an indication of the different applicability of starch-based food ingredients in product development. The effect of packaging materials (cylindric polyvinyl containers and aluminum ziplock pouch bags) on quality attributes of pretreated yellow-fleshed cassava flour (YFCF) samples stored in two storage conditions a (cooling chamber at 5 °C and 30 % relative humidity and; in a climate chamber at 30 °C and 50 % relative humidity) was investigated for 8 weeks. Flour samples from each package type were evaluated for water absorption capacity, pasting and oil absorption capacity fortnightly. The treated initial flour sample before storage-sulfured (BSS) had the highest peak viscosity (891 RVU). The low peak time at the end of storage in non-sulfured flours packed in aluminum pouch bags and stored at 5 °C is an evidence of time and energy saving capacity. The water absorption capacity of non-sulfured flour samples packed in cylindric polyvinyl containers and the sulfured flour sample packed in an aluminum pouch bag at 30 °C increased with storage duration. The aluminum ziplock pouch bags showed excellent storage quality and retained better pasting property. The climatic storage condition revealed better keeping quality. The use of sodium metabisulphite revealed its suitability as a pretreatment tool.

Assessment of the Addition of Cricket (Acheta domesticus) Powder to Chickpea (Cicer arietinum) and Flaxseed (Linum usitatissimum) Flours: A Chemometric Evaluation of Their Pasting Properties

Edible insects have been evaluated as an alternative and sustainable source of protein because of their nutritive and functional properties for humans and domestic animals. The objective of this study was to assess the use of chemometric [principal component analysis (PCA) and partial least squares (PLS)] combined with Rapid Visco Analyser (RVA) profiles to evaluate the addition of cricket powder (CKP) to chickpea (CPF) and flaxseed (FxF) flours. The results of this study showed that the addition of CKP powder to both CPF and FxF flours affects the pasting properties of the samples; in particular, a reduction in the peak (PV) and final viscosity (FV) was observed. The use of chemometric data techniques such as PCA and PLS regression allowed for a better interpretation of the RVA profiles. Both PCA and PLS regression allowed to qualitative and quantitatively identify the addition level of CKP powder to CPF and FxF flour samples. Differences in the PLS loadings associated with the RVA profile due to the addition of cricket powder were observed. The development of these methodologies will provide researchers and the food industry with better tools to both improve and monitor the quality of ingredients with functional properties as well as to further understand the use of insects as alternative sources of protein.