Research Article
Food Technology
Salimeh Ebrahimi Meymand; Leila Jafari; Abdolmajid Mirzaalian Dastjerdi; Asghar Ramazanian
Abstract
IntroductionSapodilla is a tropical fruit well-known for its sweet taste and soft texture. It is a fruit that continues to ripen naturally after being harvested. Therefore, the fruit harvesting time must be chosen carefully to ensure that the fruit reaches a stage of ripeness where it has the desired ...
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IntroductionSapodilla is a tropical fruit well-known for its sweet taste and soft texture. It is a fruit that continues to ripen naturally after being harvested. Therefore, the fruit harvesting time must be chosen carefully to ensure that the fruit reaches a stage of ripeness where it has the desired flavor and quality. Sapodilla continues to ripen naturally after harvest, so selecting the right time for picking is crucial for ensuring optimal flavor and quality. Proper post-harvest handling, such as controlling temperature and humidity, can extend its shelf life. Using edible coatings or suitable packaging also helps preserve its freshness and delay spoilage. Maintaining quality and reducing post-harvest fruit deterioration is one of the significant challenges in the agricultural supply chain, requiring effective protective methods. The spoilage of sapodilla fruit is due to its sensitivity to temperature conditions and water loss. Application of amino acids can help preserve its quality and extend its shelf life. In this study, phenylalanine, glutathione, melatonin, L-arginine, and control (distilled water) were applied to evaluate post-harvest quality of sapodilla over five storage periods with three replications.Materials and MethodsFirst, sapodilla fruits were harvested from an orchard located in Rodan City at the stage of commercial maturity in the second half of July. Immediately after harvesting, the fruits were transported to the Horticultural Science Laboratory at the Faculty of Agriculture, University of Hormozgan. The harvested fruits were healthy and free from pests and diseases. They were selected based on uniform shape and weight. After being washed, the fruits were disinfected in a 1% sodium hypochlorite solution for 2 minutes. Following disinfection, the fruits were dried in ambient air.The fruits were treated with four amino acids (phenylalanine (8 mM), glutathione (0.05%), melatonin (0.5 mM) and L-arginine (1 mM)) and control (distilled water) for 10 minutes. After the treatment, they were transferred to the cold room with a temperature of 8 ± 1 C° and a relative humidity of 90 ± 5 %. The factorial experiment was conducted in five storage times (0, 10, 20 30 and 40) in three replications as a completely random design and the quality and biochemical factors of sapodilla were measured. Results and DiscussionIn this study, the weight loss of Sapodilla fruit increased with storage time, while the treatments helped prevent weight loss. At the end of the 40-day storage, the phenylalanine treatment prevented 37.9% of the weight loss compared to the control. Phenylalanine treatment prevented 92.33% of the weight loss relative to the control. The fruit firmness decreased over time, whereas treatments helped increase this parameter. The highest and lowest firmness values at the end of the experiment were observed in the melatonin and glutathione treatments (97.67 and 66.66 N, respectively), with the control having the lowest firmness (57.55 N). Soluble solids content increased over time. The highest and lowest soluble solids were found in the control and the treatments with arginine, melatonin, and glutathione, respectively. At the end of the 40-day experiment, the arginine, melatonin, and glutathione treatments reduced soluble solids content, compared to the control by 6.98%, 6.60%, and 6.41%, respectively. The greatest and least increases in soluble solids were observed in the control and the treatments with L-arginine and glutathione, respectively. After 40 days of storage, the L-arginine and glutathione treatments reduced the decay percentage by 45.81% and 41.43%, respectively, compared to the control. Glutathione treatment increased the ascorbic acid content of sapodilla fruit at most storage times. At the end of storage (40 days), glutathione treatment increased ascorbic acid content by 56.79% compared to the control. An increase in antioxidant activity was observed in Sapodilla fruit over time. On day 30 of storage, phenylalanine treatment increased antioxidant activity by 28.67%, and on day 40, melatonin treatment showed a 30.61% increase. This increase in antioxidant activity is considered a defense response to environmental and physiological stress during storage. At the end of 40-day storage period, catalase activity increased. The highest and lowest catalase activities were observed at 33.06 and 25.22 units/mg fresh weight, respectively. By day 40, catalase activity was increased to 31.08% in the arginine treatment compared to the control. ConclusionIn conclusion, using these treatments, particularly phenylalanine, melatonin, and glutathione, can serve as effective strategies for preserving the quality of sapodilla fruit during long-term storage and mitigating the negative effects of physiological and environmental stress. These treatments not only reduce weight loss, maintain firmness, and prevent decay, but also improve the nutritional properties and health benefits of the fruit by enhancing antioxidant activity and defense enzyme levels. In the future, further research could focus on identifying the precise mechanisms by which these compounds influence the biochemical processes in sapodilla and other fruits. Furthermore, studying the long-term effects of these treatments, as well as their interactions with various environmental and physiological factors in real-world storage conditions, could pave the way for wider adoption of these strategies in the fruit storage and packaging industry. These investigations could enhance fruit preservation methods, minimize food waste, and prolong the shelf life of fruits and decresing postharvest loss.
Research Article
Food Engineering
Maryam Fathifar; Nasser Sedaghat; Mohammad Reza Abdollahi Moghadam
Abstract
IntroductionPackaging is an intermediary between the produced food products and the customer, which maintains the quality of the product and provides the information required by the customer. The primary function of packaging is to preserve the nutritional quality of products and extend their shelf life. ...
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IntroductionPackaging is an intermediary between the produced food products and the customer, which maintains the quality of the product and provides the information required by the customer. The primary function of packaging is to preserve the nutritional quality of products and extend their shelf life. Conventional packaging materials, such as polyethylene, polypropylene, and polystyrene, are derived from petroleum-based sources and are widely utilized in food packaging due to their advantageous properties, including high durability, lightweight nature, cost-effectiveness, ease of manufacturing, and low water vapor permeability. However, degradation of these synthetic materials is very slowly in the environment, leading to significant ecological pollution. In response to this issue, there has been growing interest in the use of biopolymer materials as a sustainable alternative to non-biodegradable, petroleum-derived packaging. Biodegradable biopolymers offer several benefits, such as environmental degradability and lower production costs compared to synthetic polymers. Additionally, in certain applications, biopolymers can enhance product shelf life and quality, making them a promising solution for sustainable packaging.Materials and MethodsIn this study, a polylactic acid/polyethylene blend film reinforced with graphene oxide nanoparticles was produced and then its mechanical, physical, and antimicrobial properties were investigated in two phases.Phase 1In this phase, three-component blends of blown film-type linear low-density polyethylene, general film-type low-density polyethylene, and extruded sheet-type polylactic acid were prepared. For this purpose, 80 wt% linear low-density polyethylene with 20 wt% low-density polyethylene and part 3, 6, and 9 part per hundred (phr) polylactic acid in the presence of 0.05 phr of maleic anhydride-linked polyethylene compatibilizer were melt-blended in a high-performance twin-screw extruder. Before mixing and extruding, linear polyethylene, polyethylene, and polylactic acid granules were dried in a dryer at 80°C for 6 hours to remove moisture before the process. After mixing, a blown film was prepared from the mixture using a single-layer blown extrusion machine. In this stage, the optimal film was selected by performing various analyses.Phase 2The optimal film selected from the first stage was used to investigate the effect of graphene nanooxide in the second stage. For this purpose, first, graphene nanooxide with phr concentrations of 0, 1, 3 and 5 relative to the three-component mixture was well dispersed in the polylactic acid solution by ultrasonication. After drying in a thermal oven, the solution was poured into a co-rotating twin-screw extruder along with linear low-density polyethylene, low-density polyethylene, and maleic anhydride-linked polyethylene compatibilizer for processing and granulation. After that, a nanocomposite film was prepared according to the first phase method. In order to investigate the effect of nano graphene oxide on the properties of the produced films, all relevant analyses were performed.Results and DiscussionThe results showed that with the addition of PLA to the polyethylene matrix, due to the immiscibility of these two materials, two peaks appeared at 122 and 165 °C in the thermogram of the blend, which was related to the melting temperatures of polyethylene and polylactic acid, respectively. The tensile strength and tensile modulus of the blends increased significantly with increasing PLA and GO content, so that the sample with 9 phrof polylactic acid and 5 phr of graphene oxide (LDP9-G5), had the highest tensile strength and tensile modulus, 19.2 and 224 MPa. The oxygen transfer rate decreased with increasing GO content. So that the transmission rate for sample LDP9 was 425 cm3/m2.d and for samples LDP9-G1, LDP9-G3 and LDP9-G5 were 417, 402 and 380 cm3/m2.d, respectively. The ultraviolet light transmittance also showed that with increasing GO content in the film, the ultraviolet light transmittance and transparency of the films decreased. The antimicrobial and antifungal test of nanocomposite films also showed a decrease in the microbial population with increasing GO concentration. Positively charged ions on the GO surface react with negative charges on the bacterial membrane and inactivate the bacterial function. Sample LDP9-G5 had the highest antifungal activity in the culture medium of Candida albicans. Also, the biodegradability of sample LDP9-G5 was 11% within 8 weeks.ConclusionAccording to the results obtained, it can be said that the obtained nanocomposite film showed excellent mechanical and antimicrobial properties compared to the control film sample due to the presence of graphene oxide in its structure.
Research Article
Food Technology
Sahar Kiani; Hajar Abbasi
Abstract
IntroductionRecovery of active ingredients from plants is generally carried out using solid-liquid extraction. Selecting an appropriate solvent is one of the parameters that strongly affects the extraction performance and the type of extracted compounds. So far, various solvents have been used to extract ...
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IntroductionRecovery of active ingredients from plants is generally carried out using solid-liquid extraction. Selecting an appropriate solvent is one of the parameters that strongly affects the extraction performance and the type of extracted compounds. So far, various solvents have been used to extract these compounds. In addition to the need for large amounts of solvent, the high consumption of organic solvents causes problems such as environmental pollution and possible destruction of active compounds. Green solvents have been considered for the extraction process to reduce the consumption of non-toxic solvents and protect the environment. Natural deep eutectic solvents (NADES) are a new class of solvents used in extraction that consist of a mixture of two or more biodegradable natural compounds with low or no toxicity. The important features of these solvents are their low toxicity, biocompatibility, simple preparation, and low cost. Given the significant advantages of these solvents, in recent years, the use of NADES in the extraction of phenolic and antioxidant compounds has been considered. Applying appropriate auxiliary treatments to the sample or the sample-solvent combination during the extraction process can improve the performance of the extraction process. The use of ultrasonic waves allows for better extraction by creating shear force, disrupting the integrity of the cell wall, and better penetration of the solvent into the tissue. Pulsed electric waves also create pores in the cell membrane without causing minimal damage to the other parts, while maintaining consistency and structure, accelerating the permeability and transport of water and dissolved substances from the cell membrane, and allowing the extraction of active substances under better conditions.Materials and MethodsThis study was conducted in 3 phases to extract the compounds of the golden plant using natural deep eutectic solvents. In the first phase, effect of the type of solvent used including carboxylic acids (citric acid and malic acid), sugars (glucose and fructose), and sugar alcohols (ethylene glycol and glycerol) on the quality of the extracted material was evaluated. In the second phase, to improve the possibility of extracting the active ingredient of this plant, the sample was treated with pulsed electric waves, and in the third phase, the extraction of phenolic compounds from the sample was carried out with the solvent type selected from the first phase under the conditions of applying and non applying ultrasonic waves. Identification of the compounds present in the extract was carried out on the selected samples using HPLC. Finally, the ability to recover the extracted compounds was carried out from the best sample. Statistical analysis of the results was carried out using a completely randomized design - factorial test with SAS VERSION 9 software.Results and DiscussionThe extract from the eutectic solvent containing ethylene glycol due to its high antioxidant activity and the extract from the eutectic solvent containing maleic acid due to its high phenolic compounds were selected as the best solvents for making the Dracocephalum kotschyi extract. Considering the total number of identified compounds, the content of identified compounds in the extract with a eutectic solvent containing ethylene glycol was 17000.05 μg/g, and in the extract with a eutectic solvent containing maleic acid was 10029.1 μg/g. Therefore, the content of active compounds of an extract with a eutectic solvent containing ethylene glycol was about 70% higher than the content of active compounds of an extract with a eutectic solvent containing maleic acid, and this solvent was selected for further studies. The study of the effect of applying electric pulses and ultrasonic waves on the extraction process shows that by increasing the intensity of the electric pulse and the duration of using ultrasonic waves, the content of phenolic compounds and antioxidant properties of the extract increased. Electric pulses accelerate the permeability and transport of water and dissolved substances by creating pores in the cell membrane. The change in the properties of the cell wall membrane in such a way that the substances inside the cell can be quickly and easily removed from the cell, causes the extraction to be carried out in the minimum time and energy required. The total weight of phenolic compounds identified in the extract with a eutectic solvent containing ethylene glycol with the application of auxiliary was 25275.41 μg/g, without the application of auxiliary treatments was 17000.05 μg/g, and in the sample extracted with ethanol was 21652.89 μg/g. Therefore, the application of auxiliary treatments was effective and superior to the ethanol solvent in increasing the extraction of compounds from the plant. The polyphenol content extracted with ethylene glycol-choline chloride with and without auxiliary treatments was determined as 53 and 45 percent, respectively.ConclusionThe solvent containing choline chloride-ethylene glycol had the best conditions for extracting the active compounds of Dracocephalum kotschyi. Applying a 5000 W electric pulse pretreatment and using ultrasonic waves for 30 minutes in the extraction stage had a significant effect in increasing the extractability of the active compounds. Using the anti-solvent (water) precipitation method, 53% of the phenolic compounds were recovered and the eutectic solvent was returned to the system.
Research Article
Food Technology
Fatemeh Islami; Zeynab Raftani Amiri; Ali Motamedzadegan; Hayedeh Gorjian
Abstract
IntroductionFoams are colloidal systems that are formed by the accumulation of gas bubbles separated from each other by thin liquid layers. Foams have attracted a lot of attention from the food industry and culinary arts due to their unique flavor and texture properties. Marshmallows are an aerated confectionery ...
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IntroductionFoams are colloidal systems that are formed by the accumulation of gas bubbles separated from each other by thin liquid layers. Foams have attracted a lot of attention from the food industry and culinary arts due to their unique flavor and texture properties. Marshmallows are an aerated confectionery product that is mainly prepared from gelatin (as a foaming and gelling agent), sugar solution (including glucose syrup and sugar), flavoring, and coloring agents. Gelatins are amphiphilic macromolecules and are obtained from hydrolyzed collagens. Gelatin is a quite digestible protein and contains all essential amino acids except tryptophan. The simplest way to produce gelatin is to convert collagen into gelatin by denaturing or breaking down the collagen molecule to make it soluble in water. This process generally involves an acidic, alkaline, or enzymatic pretreatment. In food applications, gelatin can act as a foaming agent, emulsifier, biodegradable film former, colloidal stabilizer, and microencapsulating agent. Due to health, religious, and economic restrictions on the consumption of gelatin from mammals, other sources for gelatin production must have characteristics such as high amounts of by-product availability (Because continuous production in the industry is an essential economic issue) and a value close to the rheological properties of mammalian gelatin in order to be considered as a alternative suitable source for replacement. Hence, poultry by-products can be investigated as a new source of gelatin extraction. Materials and MethodsIn this study, gelatin was extracted, from chicken feet using an acidic method. The gelatin production process consists of three main steps: pretreatment of raw materials, gelatin extraction, purification, and drying. Gelatin of chicken feet was used in the marshmallow product at two levels of 6 and 8 percent. Physicochemical properties of gelatin including moisture, color, gel strength, rheology, fat, protein, and ash were analyzed. In the evaluation of the marshmallow, textural components, rheology, electron microscopy, differential thermal scanning, and sensory evaluation (Appearance, color, aroma, sweetness, texture, hardness, and gumminess) were determined. The sensory evaluation was conducted on a five-point hedonic scale. Statistical analysis of this study was performed with Duncan's multiple range test using SPSS software. Result and Discussion In the physicochemical analysis of gelatin extracted from chicken feet, the protein content was 78.27±0.445, fat 10±2, ash 47.6±0.46 and moisture 70.12±0.28%. In the frequency sweep test, the storage modulus was always higher than the loss modulus, indicating the high strength and viscoelastic behavior of gelatin at a given strain. In evaluating the flow behavior of gelatin obtained from chicken feet, the viscosity of the sample decreased with increasing shear rate, indicating the shear-thinning behavior of gelatin. Adding 8% gelatin to the marshmallow sample significantly increased the hardness, gumminess, and texture adhesion indices. The Overran in the sample contained 8% gelatin was 40, and the marshmallow contained 6% gelatin was 30. The presence of more protein has a positive effect on the process of reducing surface tension, and more proteins, with the polar parts of the molecule is opened towards the water, are absorbed at the interface, creating a stabilizing layer around the bubbles, which causes more foam to form and increases overran. There was no significant difference between the samples in moisture, water activity, and color a, b indices. In terms of sensory parameters of sweetness, texture firmness, gumminess, and overall acceptance, the 8% gelatin sample was given the lowest score. In the applied frequency range, the G' modulus in all samples was higher than the G" modulus, indicating viscoelastic behavior and gel strength at a definite strain. In all samples, the complex viscosity decreases linearly with increasing applied frequency, reflecting the shear-thinning behavior of the samples. Marshmallow consisting of 6% gelatin was determined as the selected formulation in terms of physicochemical, rheological, and sensory evaluation properties. ConclusionBased on the results obtained from this research and In order to optimally utilize chicken waste, this innovation can be used to produce health-oriented and cost-effective product.
Research Article
Food Biotechnology
Mohaddeseh Larypoor; Neda Jameyi; Hoora Dadgostar; Jamileh Nowroozi
Abstract
IntroductionProbiotics are live, beneficial microorganisms that, when administered in adequate amounts, provide significant health benefits to the host. They play a vital role in maintaining and restoring gastrointestinal microbiota balance, improving digestion, modulating the immune system, and protecting ...
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IntroductionProbiotics are live, beneficial microorganisms that, when administered in adequate amounts, provide significant health benefits to the host. They play a vital role in maintaining and restoring gastrointestinal microbiota balance, improving digestion, modulating the immune system, and protecting against pathogenic bacteria. Prebiotics are non-digestible food components—typically fibers or complex carbohydrates—that selectively stimulate the growth and activity of beneficial gut microorganisms. By fostering a favorable environment for probiotics, prebiotics indirectly promote host health.Recently, the search for natural and cost-effective prebiotic sources has intensified. Medicinal mushrooms, particularly Ganoderma lucidum (reishi) and Lentinula edodes (shiitake), have emerged as promising candidates due to their abundance of bioactive polysaccharides. These polysaccharides not only exhibit prebiotic potential but also possess antioxidant, immunomodulatory, and anti-inflammatory properties.This study aimed to investigate the prebiotic properties of polysaccharides extracted from G. lucidum and L. edodes. Specifically, we evaluated their ability to stimulate the growth and metabolic activity of probiotic yeast and bacterial isolates obtained from traditional and industrial dairy products. These natural polysaccharides may contribute to the development of novel synbiotic products with enhanced health benefits.Materials and MethodsTwenty dairy product samples were collected and subjected to microbial isolation to obtain yeast and bacterial strains with probiotic potential. Isolates were identified using morphological, biochemical, and molecular techniques, including PCR and sequencing.Polysaccharides were extracted from the mycelium of G. lucidum and L. edodes via lyophilization and aqueous extraction. Carbohydrate content was determined using the phenol-sulfuric acid assay, while antioxidant capacity was assessed using the DPPH free radical scavenging method. FT-IR spectroscopy was employed to characterize chemical structures.The prebiotic effects of the mushroom polysaccharides were evaluated by supplementing sugar-free culture media with these extracts. Growth and metabolic activity of selected probiotic isolates were compared to the ontrols supplemented with glucose and inulin. Enzymatic and acid digestion assays were also performed to assess the stability of the polysaccharides under simulated gastrointestinal conditions.Results and DiscussionMultiple yeast and bacterial isolates were obtained from the dairy samples. Following biochemical screening, four isolates—A3, A10, B1, and B3—were selected for detailed analysis based on their probiotic potential. Antibiogram testing revealed varied resistance and sensitivity profiles.Molecular identification showed that isolate A10 was closely related to Candida tropicalis, while A3 matched Saccharomyces cerevisiae. Among the bacterial isolates, B1 was identified as Lactobacillus casei and B3 as Lactobacillus acidophilus.Polysaccharides extracted from G. lucidum and L. edodes exhibited lower reducing sugar content compared to inulin, indicating a more complex carbohydrate structure and greater resistance to enzymatic breakdown. Antioxidant assay demonstrated that, while inulin had the highest free radical scavenging activity, the mushroom polysaccharides also showed significant antioxidant properties.FT-IR spectra confirmed the presence of characteristic polysaccharide functional groups, such as hydroxyl, carboxyl, and glycosidic linkages, consistent with previous findings on medicinal mushroom polysaccharides.When added to sugar-free media, polysaccharides from both mushrooms stimulated the growth of probiotic isolates, though to a lesser extent than glucose and inulin. This suggests that while these fungal polysaccharides act as prebiotics, their fermentability and utilization by probiotics may differ from conventional prebiotics.Optimal growth conditions for the probiotic isolates were observed at pH 5 and 37°C. The ability of these isolates to thrive under such conditions, along with their positive response to mushroom polysaccharides, underscores the potential of these compounds as functional prebiotic ingredients.This study highlights the promising prebiotic and antioxidant properties of polysaccharides extracted from G. lucidum and L. edodes. These natural compounds supported the growth of beneficial probiotic yeasts and bacteria isolated from dairy products, suggesting their potential as synbiotic supplements.ConclusionIncorporating mushroom-derived polysaccharides into functional foods and dietary supplements could enhance gastrointestinal microbiota balance and promote overall health. However, further research involving in vivo animal models and human clinical trials is necessary to fully validate the health benefits and safety of these polysaccharides. Such studies will help clarify their mechanisms of action, determine optimal dosages, and assess long-term effects, paving the way for their application in health-promoting dietary and medicinal products.
Short Article
Zeinab Rahimi; Vahid Hakimzadeh
Abstract
IntroductionIn 2023, North Khorasan province hosted 188,000 bee colonies, producing over 2,900 tons of honey. Approximately 20% of the honey in the province is produced in the Mane and Semelqan region, which is rich in orchards and agricultural fields. To increase agricultural production, various pesticides ...
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IntroductionIn 2023, North Khorasan province hosted 188,000 bee colonies, producing over 2,900 tons of honey. Approximately 20% of the honey in the province is produced in the Mane and Semelqan region, which is rich in orchards and agricultural fields. To increase agricultural production, various pesticides are widely used in this area, thereby increasing the potential for contamination of bees and their products, which are often located near these fields. Pesticides residues have been reported to be toxic, carcinogenic, and capable of causing chromosomal changes (Demirhan et al., 2019). They can also affect the endocrine, reproductive, and nervous systems (Brander, Gabler, Fowler, Connon, & Schlenk, 2016; Watermann et al., 2016; Febvey, Schüz, & Bailey, 2016). Diazinon, an organophosphorus insecticide, is classified in the second category of the World Health Organization's classification and is considered a relatively dangerous pesticide (Taghavi, Naghipour, Mohagheghyan, & Jamali, 2007). This study aims to investigate the residual levels of diazinon in honey produced in the Mane and Semelqan region, including Buor Buor village (cotton flower honey), Chakhmaghloo village (kanar honey), Keshanak village (spring honey), and Darkesh village (thyme honey), with the goal of evaluating the safety of honey produced in this region.Materials and MethodsHoney samples were collected in the spring (May) and winter (March) of 2023. To prepare the honey samples for determining diazinon pesticide residue, the method of Jime´nez, Bernal, & Lorente, (2000) was used. A standard dilution of diazinon was prepared at concentrations of 0.12, 0.06, 0.024, 0.012, and 0.006 ppm. The absorption spectrum of the diluted solutions was then recorded using an ultraviolet-visible (UV-Vis) spectrometer in the wavelength range of 200 to 400 nm. Based on the spectral results, the maximum absorption wavelength (λ_max) of diazinon was determined to be 292 nm. The best-fit equation with a correlation coefficient (R² = 0.9905) was calculated. Data were analyzed using a completely randomized design with five replicates for each season (spring and winter) through the GLM procedure of SAS 9.1 statistical software (SAS, 2009).Result and DiscussionThe results showed that the amounts of diazinon in the honey samples from Buor Buor, Darkesh, Keshanak, and Chakhmaghloo villages were 3.46, 2.73, 1.81, and 1.49 ppm, respectively. The diazinon residue in the honey from Buor Buor (3.46 ppm) and Darkesh (2.37 ppm) villages was significantly higher than the diazinon residue in the honey from Chakhmaghloo (1.49 ppm) and Keshanak (1.81 ppm) villages (P < 0.001). Additionally, the residual amount of diazinon in honey harvested in the spring was 4.23 ppm, significantly higher than in the winter samples, which had 0.34 ppm (P< 0.001). Unfortunately, the residual amount of diazinon pesticide in all honey samples from different regions of Mane and Semelqan exceeded the standard limit set by authorities in Iran and Europe. ConclusionIt can be concluded that the honey from Mane and Semelghan region contains higher levels of diazinon residue compared to the standard limit, which can be attributed to the spraying of pesticides in orchrds and fields. Additionally, the lower pesticide residue in the winter honey samples may be due to manual feeding of bees, reduced agricultural activity during the winter season, and possibly the washing off of pesticide residues by rainfall. Therefore, considering the higher levels of diazinon residue in the honey samples compared to the permissible limit, and the higher amount in this residue during the spring season, it is recommended to strengthen the monitoring of pesticide application in agricultural fields surrounding beekeeping areas, particularly in the spring. Additionally, educating farmers on the proper use of pesticides, informing beekeepers about high-risk areas, and regularly screening honey samples can help reduce the risks associated with pesticide residues. Investigating safer alternatives to diazinon and establishing regional regulations are also among recommended measures to improve food safety and protect consumer health.
Short Article
Food Chemistry
Zahra Zarezade; Ali Forouhar; Hamed Saberian
Abstract
IntroductionAcorn, a traditional component of the human diet, is a rich source of bioactive compounds, especially polyphenols and tannins, which possess antioxidant, antibacterial, and antiviral properties. These compounds have extensive applications in the food, pharmaceutical, and chemical industries. ...
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IntroductionAcorn, a traditional component of the human diet, is a rich source of bioactive compounds, especially polyphenols and tannins, which possess antioxidant, antibacterial, and antiviral properties. These compounds have extensive applications in the food, pharmaceutical, and chemical industries. However, their yield and purity depend highly on extraction conditions, including solvent type and polarity, temperature, extraction time, particle size, and solid-to-solvent ratio. Solvent extraction is the most widely used among various extraction techniques due to its simplicity and efficiency. Given the limited data on tannins from native acorns in Chaharmahal and Bakhtiari Province, this study aims to evaluate the effect of solvents with varying polarity and pH on tannin extraction. The purity of extracted tannins was also determined using HPLC. The findings of this research could serve as a basis for optimizing the extraction of valuable compounds from acorn and facilitating the industrial utilization of these native resources.Materials and MethodsTo extract tannins from acorn shell, cupule, and shell-cupule mix, the samples were ground and passed through a 40-mesh sieve. Extraction was carried out using three types of solvents: distilled water, 40% ethanol solution, and 0.22% sodium hydroxide solution. The process was performed at two temperatures (60°C and 90°C) with a solid-to-liquid ratio of 1:10, for one hour under continuous stirring. The resulting extracts were filtered and then dried at 50°C. To determine the actual extraction yield in alkaline-treated samples, the amount of sodium hydroxide was quantified by titration with HCl, and its mass was subtracted from the dry extract weight to obtain the real extraction yield. Total phenolic content was measured using the Folin–Ciocalteu method by determining absorbance at 760 nm. Tannin content was estimated by subtracting non-tannin phenolics from total phenolics using PVPP as an adsorbent. In this method, PVPP was added to the extract, and after centrifugation, non-tannin phenolics were separated, allowing tannin content to be calculated by difference. HPLC analysis was performed using a C18 column and a detector set at 280 nm to confirm the presence of tannins. Tannic acid was used as the standard, and separation was achieved using a gradient of formic acid and acetonitrile. Statistical analyses were conducted using SPSS, and graphs were plotted using Excel.Results and DiscussionThe effects of solvent type and extraction temperature were examined for tannin extraction. The results indicated that increasing the temperature from 60°C to 90°C enhanced extraction yields for both distilled water and 0.22% sodium hydroxide solution. However, the effect of temperature increase was significantly more pronounced under alkaline conditions. Higher temperatures improve solvent penetration, reduce viscosity, and accelerate the diffusion of bioactive compounds, which markedly boosts tannin extraction in combination with an alkaline solvent. Regarding solvent type, ethanol demonstrated superior performance in tannin extraction. Due to its dual nature (polar and non-polar), ethanol efficiently extracted a broad spectrum of phenolic compounds. The average tannin yield using ethanol was around 51.41%, which surpassed other treatments, including alkaline extraction at high temperature (48.06%). This highlights ethanol’s strong capacity to extract condensed tannins, which are abundant in acorns. Moreover, ethanol tended to extract fewer impurities, such as carbohydrates, than polar solvents like sodium hydroxide, thereby increasing the purity of the tannin extracts. Further analysis of the total phenolic content revealed that the source material (cupule or shell) and solvent type significantly influenced the extraction yield. The highest total phenolic content (61.22%) was obtained from the cupule using sodium hydroxide, significantly exceeding other materials and treatments. This confirms the cupule’s richness in phenolic compounds, though given its lower proportion in the acorn structure, using a blend of cupule and shell is more practical. Additionally, ethanol and sodium hydroxide achieved higher yields than water, underscoring the beneficial role of alkaline and semi-polar solvents in phenolic compound release. Further specific analysis of tannin extraction also showed that ethanol-based treatments yielded the highest results. The use of 40% ethanol nearly doubled the tannin yield compared to aqueous and alkaline treatments. This high efficiency is attributed to the better solubility of tannins in polar-organic solvents like ethanol. On the other hand, extraction with sodium hydroxide at lower temperatures (60°C) resulted in lower yields, emphasizing the combined effect of temperature and solvent on extraction efficiency. HPLC analysis for tannic acid quantification confirmed that the tannin content of the shell-cupule mix and cupule alone was 48.06% and 61.23%, respectively. These findings emphasize the practical value of using a shell-cupule mixture as an industrial tannin source, as it not only contains a substantial amount of tannin but also offers better availability and a higher weight proportion compared to the cupule alone.ConclusionThis study highlights the significant influence of extraction conditions, particularly solvent type and temperature, on the extraction yield of tannins and phenolic compounds from acorn resources. Alkaline extraction at elevated temperatures was more effective for tannin extraction from the shell-cupule mix, while ethanol exhibited high efficiency due to its semi-polar nature. Although the acorn cupule is richer in total phenolics, the higher abundance of the cupule-shell blend in the fruit makes it a more practical target for industrial tannin production.
