Aflatoxins in the rice production chain: A review on prevalence, detection, and decontamination strategies.

Rice (Oryza sativa L.) is one of the most consumed cereals that along with several important nutritional constituents typically provide more than 21% of the caloric requirements of human beings. Aflatoxins (AFs) are toxic secondary metabolites of several Aspergillus species that are prevalent in cereals, including rice. This review provides a comprehensive overview on production factors, prevalence, regulations, detection methods, and decontamination strategies for AFs in the rice production chain. The prevalence of AFs in rice is more prominent in African and Asian than in European countries. Developed nations have more stringent regulations for AFs in rice than in the developing world. The contamination level of AFs in the rice varied at different stages of rice production chain and is affected by production practices, environmental conditions comprising temperature, humidity, moisture, and water activity as well as milling operations such as de-husking, parboiling, and polishing. A range of methods including chromatographic techniques, immunochemical methods, and spectrophotometric methods have been developed, and used for monitoring AFs in rice. Chromatographic methods are the most used methods of AFs detection followed by immunochemical techniques. AFs decontamination strategies adopted worldwide involve various physical, chemical, and biological strategies, and even using plant materials. In conclusion, adopting good agricultural practices, implementing efficient AFs detection methods, and developing innovative aflatoxin decontamination strategies are imperative to ensure the safety and quality of rice for consumers.

Optimization of an ultrasound-assisted extraction method to obtain gallic acid-rich extracts from mango seed kernels.

Gallic acid is a widely recognized bioactive compound that falls under the category of secondary polyphenolic metabolites and is fairly found in mango fruit waste, specifically in mango seed kernel (MSK). This study aimed to adopt a green extraction approach to extract this valuable compound via ultrasound-assisted extraction (UAE) without using organic solvents but only water to obtain hazard-free extracts, and the cost of extraction can be minimal. pH (2-8), solvent ratio (20-60 mL/g), temperature (30-60°C) and time (30-60 min) of extraction were the independent variables used for extraction optimization. Single-factor experiments to obtain working ranges for selected extraction variables were carried out. A central composite design using response surface methodology was used to determine the optimum condition to obtain the maximum yield of gallic acid from MSK. The optimized extraction conditions were 3.9 pH, 36.25 mL/g solvent ratio, and 39.4°C of extraction temperature for 21.3 min. As a result, the optimized yield was 5.76 ± 0.41 mg/g, which was comparably equal to and/or better than the other solvent extraction systems. The results showed that gallic acid could efficiently be extracted via UAE under these optimal conditions. It is safer than extraction systems involving hazardous solvents that can be feasibly used for its nutraceutical and therapeutic applications.

Modification of the drug resistance of emerging milk-borne pathogens through sodium alginate-based antibiotics and nanoparticles.

Streptococcus agalactiae and Klebsiella pneumoniae are emerging as major milk-borne pathogens. Additionally, resistance to antibiotics of pathogens is of concern. Therefore, this study investigated the prevalence and drug resistance of S. agalactiae and K. pneumoniae in mastitis milk samples and assessed the antimicrobial potential of sodium alginate (G)-stabilized MgO nanoparticles (M) and antibiotics (tylosin [T] and ampicillin [A]) against both of these pathogens. A total of n = 200 milk samples from cattle were collected using purposive sampling, and standard microbiological approaches were adopted to isolate target bacteria. Parametric and non-parametric statistical tests were used to analyze the obtained data. Four preparations, GT (gel-stabilized tylosin), GA (gel-stabilized ampicillin), GTM (tylosin and MgO nanoparticles stabilized in gel), and GAM (ampicillin and MgO nanoparticles stabilized in gel), were evaluated against both bacteria through well diffusion and broth microdilution method. The analysis revealed that 45.24% (95/210) of the milk samples were positive for mastitis, of which 11.58% (11/95) were positive for S. agalactiae and 9.47% (9/95) were positive for K. pneumoniae. S. agalactiae had a significantly higher zone of inhibition (ZOI) than K. pneumoniae against penicillin, tetracycline, and amoxicillin, whereas the opposite was observed against imipenem and erythromycin. All gel (G)-based preparations showed an increase in the percentage of ZOI compared with antibiotics alone, with GTM presenting the highest of all, i.e., 59.09 and 56.25% ZOI compared with tylosin alone against S. agalactiae and K. pneumoniae, respectively. Similarly, in a broth microdilution assay, the lowest MIC was found for K. pneumoniae (9.766 ± 0.0 µg/mL) against GTM, followed by GT, GAM, and GA after incubation for 24 h. A similar response was noted for preparations against S. agalactiae but with a comparatively higher MIC. A significant reduction in MIC with respect to incubation time was found at 8 h and remained until at 20 h against both pathogens. The cytotoxicity of the MgO nanoparticles used in this study was significantly lower than that of the positive control. Overall, this study found that K. pneumoniae and S. agalactiae appeared higher in prevalence and antimicrobial resistance, and sodium alginate-based antibiotics and MgO nanoparticles were effective alternative approaches for tackling antimicrobial resistance.

Cucumis melo seed oil: agro-food by-product with natural anti-hyperlipidemic potential.

BACKGROUND: Sweet melon (Cucumis melo) seed is generally considered as agro-waste, however, the current study aimed to use this waste as a valuable oil source. The seed oil extracted by two different extraction techniques (cold press and solvent extraction) was investigated for its anti-hyperlipidemic potential. Hyperlipidemic rabbits were fed on the diet supplemented with sweet melon seed oil for 6 weeks (42 days) and thoroughly examined for the change in their lipid profile. RESULTS: The blood lipid profile indicated a significant decrease in total cholesterol triglyceride and low-density lipoprotein (LDL) contents of blood in hyperlipidemic rabbits fed on the diet supplemented with sweet melon seed oils while high-density lipoprotein (HDL) contents showed a noteworthy increase during the study period. CONCLUSION: Cucumis melo seed oil can be used to control hyperlipidemia without restricting the intake of lipids in diet. Solvent extraction provided better results regarding extraction yield and product functionality than cold press method. © 2022 Society of Chemical Industry.

Microbial toxins in fermented foods: health implications and analytical techniques for detection.

Recently, demand for fermented foods has increased due to their improved nutritional value, taste, and health-promoting properties. Worldwide consumption of these products is increasing. Fermented foods are generally safe for human consumption. However, some toxins, primarily biogenic amines (putrescine, phenylethylamine, histamine, tyramine, and cadaverine), mycotoxins (fumonisins, aflatoxins, ochratoxin A, zearalenone, and trichothecenes), and bacterial toxins (endotoxins, enterotoxins, and emetic toxins) can be produced as a result of using an inappropriate starter culture, processing conditions, and improper storage. These toxins can cause a multitude of foodborne illnesses and can lead to cardiovascular aberration and adverse gastrointestinal symptoms. Analytical techniques are in use for the detection of toxins in fermented foods for monitoring and control purposes. These include culture, chromatographic, immunoassays, and nano sensor-based techniques. These detection techniques can be used during the production process and along the food chain. On an industrial scale, HPLC is widely used for sensitive quantification of toxins in fermented foods. Recently, biosensor and nano sensor-based techniques have gained popularity due to accuracy, time efficiency, and simultaneous detection of multiple toxins. Other strategic methods being investigated for the removal of toxins from fermented foods include the use of specific starter cultures for bio-preservation, aflatoxin-binding, and biogenic amine-degradation agents that may help to appropriately manage the food safety concerns associated with fermented foods.

Effect of apple pomace on nutrition, rheology of dough and cookies quality.

Agro-industrial waste material is a rich source of various bioactive components and fiber. Apple pomace is a by-product of apple juice processing unit. It contains a plethora of phenolic compounds and dietary fiber. The addition of apple pomace in bakery items is a judicious approach to utilize the apple juice processing industry waste material in nutritional product development. Purposely, in the current research the apple pomace was collected from the juice processing industry followed by drying at 58-60 °C. The dried pomace was ground added in wheat flour (AARI-11) at 5, 10, 15, 20 and 25% to prepare cookies. The wheat flour (AARI-11) contained crude fiber (0.57%), crude protein (10.71%) and total phenolic contents (1.35 mg/g) while apple pomace showed higher contents of dietary fiber and total phenolic contents i.e. 10.85% and 9.75 mg/g respectively. Maximum values of physical characteristics of cookies such as thickness and width were found in T0 as 1.47 mm and 5.13 mm, respectively. On the other hand, spread factor and hardness changed and maximum value was observed in T5 as 46.20 and 1555.5 n/m2 respectively. Based on the sensory and compositional attributes, it was concluded that good quality cookies with improved organoleptic properties can be prepared through using 10% apple pomace powder with wheat flour.

Assessment of microbial contaminations in commercial frozen duck meats and the application of electron beam irradiation to improve their hygienic quality.

BACKGROUND: High microbial load is a serious concern in terms of the health-related safety of products of animal origin. In this study, the microbial loads of commercial frozen duck-meat products, including bone-in whole raw, boneless sliced raw, and boneless whole smoked, were investigated for pathogenic contamination. The application of electron beam irradiation was also investigated. RESULTS: The samples revealed a serious microbial threat (102 -105 CFU g-1 for total aerobic bacteria and positive for foodborne pathogens), which required effective decontamination technology. Electron-beam irradiation (0, 1, 3, and 7 kGy) could potentially improve the hygienic quality of duck-meat samples. The D10 values for Listeria monocytogenes and Salmonella Typhi were 0.47 and 0.51 kGy, respectively. A direct epifluorescent filter technique and aerobic plate count (DEFT/APC) method was used for screening, while electron-spin resonance (ESR) spectroscopy and gas chromatography with mass spectrometry were effective as confirmatory techniques to identify radiation-induced markers in frozen duck meat. CONCLUSION: Electron-beam irradiation has the potential to ensure the microbial safety and hygienic quality of commercial duck meats. Identification of the samples for their irradiation history was also possible using radiation-induced detection markers, including the DEFT/APC, hydroxyapatite ESR radicals, and hydrocarbons. © 2018 Society of Chemical Industry.

Improved Extraction and Quality Characterization of Water-Soluble Polysaccharide from Gamma-Irradiated Lentinus edodes.

Gamma irradiation was applied to the improved extraction of water-soluble polysaccharides (WSPs) from dried Lentinus edodes. Irradiation provided a dose-dependent increase in extraction yield (0 kGy, 2.01%; 7.5 kGy, 4.03%; 15 kGy, 7.17%) and purity (0 kGy, 78.8%; 7.5 kGy, 83.1%; 15 kGy, 85.6%) of the WSPs from hot-water extraction. The effect of irradiation was evident in the degraded microstructures and reduced molecular weights of the WSPs. However, nuclear magnetic resonance, Fourier-transform infrared, and X-ray diffraction spectroscopic analyses provided comparable structures of WSPs from nonirradiated and irradiated samples. UV-visible spectra showed a dose-dependent decline in intensity, but an improvement in thermal properties of the WSPs from the irradiated mushroom samples was observed.

Management of diabetic complications through fruit flavonoids as a natural remedy.

Diabetes mellitus is a global disorder, and a major issue for health care systems. The current review outlooks the use of fruit flavonoids as natural remedy in the prevention of diabetes mellitus. The onset of diabetes mainly depends upon genetics and lifestyle issues. Currently used therapeutic options for the control of diabetes, like dietary amendments, oral hypoglycemic drugs, and insulin, have their own limitations. Fruit flavonoids possess various antidiabetic, anti-inflammatory, and antioxidant potentials and act on various cellular signaling pathways in pancreas, white adipose tissue, skeletal muscle, and liver function, which in result induces antidiabetic effects. Recently, antidiabetic effect of fruit flavonoids has been studied using various animal models and clinical trials. Research studies revealed a statistically significant potential of fruit flavonoids in managing the altered glucose and oxidative metabolisms in diabetes. Unlike synthetic antidiabetic agents, fruit flavonoids manage diabetes without compromising cellular homeostasis thereby posing no side effects. Further studies are required in purification and characterization of different fruit flavonoids with respect to their beneficial effect for diabetic patients.

Worldwide Status of Fresh Fruits Irradiation and Concerns about Quality, Safety, and Consumer Acceptance.

Development of knowledge-based food preservation techniques have been a major focus of researchers in providing safe and nutritious food. Food irradiation is one of the most thoroughly investigated food preservation techniques, which has been shown to be effective and safe through extensive research. This process involves exposing food to ionizing radiations in order to destroy microorganisms or insects that might be present on and/or in the food. In addition, the effects of irradiation on the enzymatic activity and improvement of functional properties in food have also been well established. In the present review, the potential of food irradiation technology to address major problems, such as short shelf life, high-initial microbial loads, insect pest management (quarantine treatment) in supply chain, and safe consumption of fresh fruits was described. With improved hygienic quality, other uses, such as delayed ripening and enhanced physical appearance by irradiation were also discussed. Available data showed that the irradiation of fruits at the optimum dose can be a safe and cost-effective method, resulting in enhanced shelf life and hygienic quality with the least amount of compromise on the various nutritional attributes, whereas the consumer acceptance of irradiated fruits is a matter of providing the proper scientific information.

Evaluation of a natural methionine source on broiler growth performance.

BACKGROUND: Methionine, a sulfur-containing amino acid, is essential for the health and growth of broilers, so its optimum level should be provided in broiler diets. Synthetic methionine sources used by poultry nutritionists may cause health hazards in broilers as, during conversion of synthetic methionine to the active form, homocysteine is produced which may be injurious to body tissues when there is a lack of coordination between methyl group donors and acceptors. Thus the present study evaluates the efficacy of a natural methionine source. RESULTS: The comparative growth performance of broilers fed synthetic and/or natural methionine was observed. Results revealed that the basal diet has a lower growth performance (P < 0.05) than all other diets. However, replacement of synthetic methionine with a naturally sourced methionine has no significant effect (P > 0.05) on weight gain, feed consumption or feed conversion ratio. Serum biochemistry values and slaughter data also indicated no effect due to two different methionine sources (P > 0.05). CONCLUSION: The results of the present study show that synthetic methionine may effectively be replaced with a naturally sourced methionine without affecting the health and growth performance of broilers. However, additional research is needed to further explore other natural sources of methionine.

Alcoholic extraction enables EPR analysis to characterize radiation-induced cellulosic signals in spices.

Different spices such as turmeric, oregano, and cinnamon were γ-irradiated at 1 and 10 kGy. The electron paramagnetic resonance (EPR) spectra of the nonirradiated samples were characterized by a single central signal (g = 2.006), the intensity of which was significantly enhanced upon irradiation. The EPR spectra of the irradiated spice samples were characterized by an additional triplet signal at g = 2.006 with a hyperfine coupling constant of 3 mT, associated with the cellulose radical. EPR analysis on various sample pretreatments in the irradiated spice samples demonstrated that the spectral features of the cellulose radical varied on the basis of the pretreatment protocol. Alcoholic extraction pretreatment produced considerable improvements of the EPR signals of the irradiated spice samples relative to the conventional oven and freeze-drying techniques. The alcoholic extraction process is therefore proposed as the most suitable sample pretreatment for unambiguous detection of irradiated spices by EPR spectroscopy.

Chemical and sensory quality of fresh pomegranate fruits exposed to gamma radiation as quarantine treatment.

The U.S. Department of Agriculture in February 2012 approved the import of fresh pomegranates subjected to irradiation as a quarantine procedure with a minimum absorbed dose of 0.4kGy against different pests. This study evaluated the application of different gamma-irradiation doses (0.4, 1, and 2kGy) in fresh pomegranate fruits and their effect on the chemical and sensory characteristics. The total soluble solids, titratable acidity, and pH values remained unaffected up to 1kGy treatment. Irradiation caused a significant decrease in the total anthocyanins and phenolic content. A strong positive correlation was observed among the antioxidant activities, total phenolics and anthocyanin contents. In general, a stronger preference was shown by sensory panelists for the juice from irradiated fruits. This study provides research-based information about the application of irradiation as a quarantine disinfestation treatment to enhance the marketing and consumer acceptance of pomegranates.

Antidiarrheal Effect of Food Fermented by Various Strains of Lactobacillus.

Various Lactobacillus species possess antidiarrheal properties due to their probiotic effects and could be utilized in the form of fermented foods for the treatment of diarrheal disease. Diarrhea is the condition of having 3 or more loose or watery bowel movements per day. This disease is a global problem causing several million deaths each year, and the major victims are children. So its prevention and control is crucial. For the treatment of diarrheal disease, antibiotics and oral rehydration solutions are used, but these therapies are not always effective to reduce the duration and frequency of diarrhea and of increase consistency. Recent studies have demonstrated the effectiveness of the natural mode (fermented food) of disease management because of its easy availability, low cost, and efficacy against diarrhea.

Luminescence properties and compositions of contaminating inorganic minerals separated from gamma-irradiated fresh and white ginsengs from different areas.

Gamma-irradiation (0-7 kGy) of ginseng is permitted in Korea for the purpose of microbial decontamination; with strict labeling, traceability and monitoring requirements. An identification study was conducted to determine the photostimulated-luminescence (PSL) and thermoluminescence (TL) properties of gamma-irradiated fresh and white ginsengs cultivated in different areas. Dosedependent PSL-based screening was possible for white ginseng samples; however, inappropriate results from non-irradiated fresh ginseng samples were obtained, showing intermediate (700 to 5,000) or positive (T2 >5,000, irradiated) PSL counts due to the abundance of minerals on the surfaces of the samples. TL analysis of separated minerals from all non-irradiated samples gave TL glow curves of low intensity with a maximum peak after 300℃. However, well-defined irradiation-specific (high intensity with a maximum peak at about 200℃) glow curves were observed for all the irradiated samples, regardless of their type and origins. TL ratios (first glow curve /second glow curve) were also determined to confirm the irradiated (>0.1) and non-irradiated (<0.1) results. SEM-EDX (scanning electron microscope-energy dispersive X-ray) and XRD (X-ray diffraction) spectroscopic analyses showed that feldspar and quartz minerals were the main source for the typical radiation-specific luminescence properties.

Investigation of radiation-induced free radicals and luminescence properties in fresh pomegranate fruits.

Radiation-induced free radicals and luminescence properties were investigated in γ-irradiated (0-3 kGy) pomegranate ( Punica granatum L.) fruits. Photostimulated luminescence (PSL) analysis showed limited applicability, and only 3 kGy-irradiated pomegranates showed positive PSL values (>5000 PCs). Thermoluminescence (TL) glow curve features, such as intensity and the presence of maximum glow peak in radiation-specific temperature range (150-250 °C), provided definite proof of irradiation, and the TL ratios (TL1/TL2) also confirmed the reliability of TL results. Scanning electron microscopy energy dispersive X-ray (SEM-EDX) analysis of the separated minerals showed that feldspar and quartz minerals were responsible for the luminescence properties. Radiation-induced cellulose radicals were detected in the seeds and rinds by ESR analysis. The ESR results were better in freeze-dried samples than in alcohol-extracted ones. A positive correlation was found between the ESR and TL signal intensities and irradiation doses; however, the most promising detection of the irradiation status was possible through TL analysis.

Characterization of radiation-induced luminescence properties and free radicals for the identification of different gamma-irradiated teas.

Two kinds (20 each) of gamma-irradiated (0, 5, and 10 kGy) tea samples, blended powders and packed in sachets (tea bags), were investigated using photostimulated luminescence (PSL), thermoluminescence (TL), and electron spin resonance spectroscopy (ESR) to identify their irradiation status. PSL-based rapid screening was possible for all the control samples except for one packed and two powdered samples. The irradiated samples presented a good dose-dependent PSL count except two powdered samples with very low PSL sensitivity. TL analysis provided the most reliable results, in which all the irradiated samples were identified using a well-defined high-intensity TL glow curve in a temperature range of 150-250 °C. The TL results were also confirmed by determining the TL ratio (TL1/TL2), which was <0.1 in all the non-irradiated samples and >0.1 in the irradiated ones. ESR spectroscopy was effective for only 3 packed and 6 powdered samples showing the radiation-induced cellulosic and sugar radical signals, respectively.

Characterization and identification of gamma-irradiated sauces by electron spin resonance spectroscopy using different sample pretreatments.

Tomato ketchup, barbeque sauce, sweet chili sauce, and spaghetti sauce were gamma irradiated at 0, 1, 5, and 10 kGy. Electron spin resonance (ESR) technique was used to characterize the irradiated sauces, targeting radiation-induced cellulose radicals and using a modified sample pretreatment method. The samples were first washed with water, and then the residues were extracted with alcohol. The non-irradiated sauces exhibited the single central signal, whose intensity showed a significant increase on irradiation. The ESR spectra from the radiation-induced cellulose radicals, with two side peaks (g=2.02012 and g=1.98516) equally spaced (± 3 mT) from the central signal, were also observed in the irradiated sauces. The improvements in the central (natural) and radiation-induced (two side peaks corresponding to the cellulose radicals) signal intensities were obvious, when compared with routine freeze-drying and alcoholic-extraction techniques.

Absorbed-dose estimation and quality attributes of gamma-irradiated fresh shiitake mushrooms.

BACKGROUND: The general use of food irradiation requires reliable identification methods as well as extensive quality characterization. Shiitake (Lentinus edodes) mushrooms, packed in polystyrene trays and covered with polyvinylchloride film, were investigated for dose-dependent identification and quality characterization upon gamma irradiation (0, 1, 2, and 3 kGy). RESULTS: Thermoluminescence (TL) analysis of separated minerals provided excellent results to characterize the irradiated mushrooms. Low-dose re-irradiation (200-600 Gy), medium-dose re-irradiation (1-3 kGy) and high-dose re-irradiation (2-6 kGy) were performed and compared using an additive dose method. An electronic-nose analysis showed a difference in the volatile profiles of mushrooms following irradiation. One-kGy-irradiated mushrooms showed similar or better quality attributes to those of the control samples. Scanning electron microscopy revealed the dose-dependent degradation in microstructure of mushrooms upon irradiation. CONCLUSION: An absorbed dosed estimation was possible using TL analysis in which 1-3 kGy re-irradiation technique gave most promising results. An E-nose analysis effectively distinguished the samples based on irradiation history. The best quality attributes were observed at 1 kGy irradiation. However, the drastic effects of irradiation were prominent in 2 and 3 kGy-irradiated mushrooms.

Potential chemical markers for the identification of irradiated sausages.

Hydrocarbons, gas compounds, and off-odor volatiles were determined for irradiated (0 or 5 kGy) commercial sausages with different fat contents (16% and 29%) during a 60-d storage period at 4 °C. Total of 4 hydrocarbons (C14:1, C15:0, C16:2, and C17:1) were detected only in irradiated sausages: the amount of C16:2 was the highest, followed by C17:1, C14:1, and C15:0. The concentrations of hydrocarbons decreased significantly (P < 0.05) with storage, but were still detectable at the end of 60-d storage. Irradiated sausages produced significantly higher amounts of CO than the nonirradiated ones. CH(4) was detected only in irradiated sausages. Dimethyl disulfide was detected only in irradiated sausages and its concentration decreased significantly (P < 0.05) with storage. Fat content of sausages showed a significant effect on the production and retention of hydrocarbons, gas compounds, and sulfur volatiles in irradiated sausages during storage. Some hydrocarbons (C16:2, C17:1, C14:1, and C15:0), CH(4) , and dimethyl disulfide were only found in irradiated sausages indicating that these compounds can be used as potential markers for irradiated sausages.