مجله علوم و صنایع غذایی ایران
سال بیست و یکم شماره 3 (پیاپی 148، خرداد 1403)

This study aimed to optimize the formulation of chitosan-caffeic acid nanogel containing Shirazi thyme (Zataria multiflora) essential oil (ZEO) and nisin. The independent variables (the concentration of chitosan nanogel, Shirazi-thyme, and nisin) were optimized based on the highest zeta potential and encapsulation efficiency, besides the lowest particle size and IC50(DPPH) values. The results of The Box-Behnken experimental design and Stepwise-response surface model showed the optimal nanogel formulation was as follows: chitosan concentration= 0.4 g; ZEO= 157.1 ppm and nisin= 10.1 ppm. The particle size, zeta-potential, antioxidant activity, and encapsulation efficiency of the optimal chitosan-ZEO-nisin nanogel were 411.39±18.11 nm, 32.90±1.10 mV, 0.79±0.06 mg.mL-1, 71.06-82.69% respectively. Moreover, the addition of optimized nanogel to the Iranian white cheese formulation showed that the treated cheese samples with ZEO and nisin (free or encapsulated in chitosan nanogel) improved the microbial quality of chess. The antimicrobial activity of the ZEO and nisin encapsulated in chitosan-caffeic acid nanogel was higher than a free form of ZEO-nisin. The Coliforms population of cheeses treated with sodium nitrate and chitosan nanogel containing ZEO-nisin was acceptable during 60 days of storage. During the storage period, the most changes in the color and texture (hardness) of the cheese samples were related to the control sample, and the least change was obtained for samples treated with sodium-nitrate and chitosan nanogel (P < 0.05). Also, the sensory quality of the sample containing ZEO and nisin was acceptable for the sensory evaluator. The sample containing chitosan nanogel received an acceptable sensory score (> 3) during 60 days of storage. In general, the potential of the nanogel in increasing the shelf-life of Iranian white cheese was comparable with sodium nitrate.

In this study, the effect of vine training system and storage time were evaluated on some grape characteristics, such as berry contamination percentage, berry shedding percentage, berry browning rate, titratable acidity, soluble solids, total phenol and the activity of peroxidase, polyphenol oxidase and phenylalanine ammonia-lyase enzymes, in order to maintain the quality of grape during storage time. Factorial experiment was conducted based on completely randomized design with two factors of vine training system (khazandeh, pergola and cordon) and storage time (zero, 20, 40 and 60 days after storage) with three replications during 2018-2019. After transferring the fruits to the cold storage with temperature of +4◦C, relative humidity of 85-90% and storage for two months, some characteristics of grape were examined on different days after storage. The results showed that the effect of storage time on berry browning was significant at the level of 1% probability. Also, the effect of interaction between vine training system and storage time on titratable acidity and on the other measured characteristics was significant at the level of 5% and 1% probability, respectively. In general, the results showed that the cordon training system had the best effect in maintaining the characteristics of grape during the storage period compared to other training methods.

In the current study, the effect of different new extraction methods including supercritical carbon dioxide extraction (SC-CO2), microwave-assisted extraction (MAE) and also conventional Soxhlet extraction (CSE) were investigated on bioactive compounds recovery from Silybum marianum seed. The crude extraction yield (22.40± 0.15%) was obtained using CSE, while the efficiency of SC-CO2 and MAE were about 89 and 50% of those obtained using CSE. The highest free radical scavenging activity in terms of DPPH and HO radicals was obtained in extract obtained using SC-CO2. From the TPC analysis, the highest and lowest value was determined in extracts obtained using SC-CO2 (102.93± 0.14 mg GAE/g) and CSE (14.50± 0.18 mg GAE/g), respectively. Fatty acid composition was analyzed using Gas Chromatography–Mass Spectrometry. Linoleic and oleic acids were determined as the main fatty acids. Finally, it can be concluded that S. marianum seed is a potential source of bioactive compounds and new extraction techniques of SC-CO2 and MAE could be suggested as promising methods to substitute conventional method for successful recovery of bioactive compounds.

Anthocyanin is one of the bioactive compounds in the world, which is the main pigment of many fruits and vegetables. Since anthocyanins have low thermal stability during food processing, the use of these compounds as natural pigments in foods is associated with challenges. Therefore, microencapsulation of anthocyanin compounds with liposomes is important. Nanoencapsulation of bioactive compounds with liposomes is an effective and efficient way to increase the stability of polyphenolic compounds. Liposomes are polar lipid vesicles that form bilayer structures in polar solvents such as water. In this research, nanoliposomes in ratios of 9-1, 8-2, 7-3 and 6-4 lecithin-cholesterol were prepared using the solvent injection method. Then, the size and zeta potential tests were conducted to determine the characteristics of the produced particles. The average particle size (average hydrodynamic diameter) and particle size distribution for different lecithin-cholesterol ratios were in the range of 132-740 nm and 0.47-0.41, respectively. Zeta potential values ​​were also obtained in the range of -26 to -42 mv. After determining the efficiency of Nanoencapsulation, FTIR test was performed to investigate possible reactions between anthocyanins and nanoliposome wall materials. The morphology of anthocyanin-loaded lecithin-cholesterol nanoliposomes with a ratio of 9-1 was shown by scanning electron microscopy (SEM). The stability of the liposomal sample with a ratio of 9-1 lecithin-cholesterol was evaluated by calculating the amount of release of encapsulated anthocyanin during 60 days of storage at ambient temperature. Samples with 9-1 lecithin-cholesterol ratio were used in Kombucha drink formulation. Prepared drinks were evaluated in terms of sensory properties and other physical and chemical characteristics (pH, acidity, Brix degree, etc.). The results obtained in this research showed that nanoliposomes are an efficient system for encapsulating of anthocyanins.

The aim of this study is to investigate the effect of gelatin film containing Bifidobacterium bifidum and Lactobacillus rhamnosus bacteria on the survival of Staphylococcus aureus bacteria inoculated into rainbow trout meat as well as its physicochemical characteristics for 12 days during storage at refrigerator. Staphylococcus aureus was inoculated into fish samples with a concentration of 106 log cfu/ml. Then the treatments (control group, rainbow trout samples packed with gelatin film, gelatin film containing each probiotic bacteria Bifidobacterium bifidum and Lactobacillus rhamnus with a concentration of 109 log cfu/ml separately and gelatin film containing both probiotics) were prepared. Samples were packed in polythene bags and stored in refrigerator. Probiotic bacteria viability and Staphylococcus aureus bacteria count, pH, TVB-N, PV and TBARS were evaluated. According to the results, the survival of probiotic bacteria showed a decreasing trend during the study, and it was found that the survival of Bifidobacterium bifidum bacteria in gelatin film treatment and gelatin film treatment containing both probiotics on the last day respectively 6.81 log cfu/g and 5.37 log cfu/g and the viability of Lactobacillus rhamnosus bacteria was also reduced by 7.43 log cfu/g and 6.31 log cfu/g respectively in the mentioned treatments. Compared to the control group, probiotic films controlled the microbial growth of fish fillets well, while the gelatin film treatment containing both probiotics had the lowest rate. Chemical tests also had an increasing trend and their changes in all treated fish fillets were significantly lower than the untreated group (P<0.05). It was found that gelatin films containing probiotics, especially gelatin films containing Lactobacillus rhamnosus and Bifidobacterium bifidum, which had worked more successfully, had an effective antimicrobial effect against Staphylococcus aureus bacteria, and this coating can increase the shelf life of rainbow trout and this The category of products has a good effect.

One of the most important challenges related to fresh meat products (especially sheep liver) is the short shelf-life of the product. For this purpose, synthetic preservative compounds are used to extend their shelf life, which have many side effects on human health. In this research, the effect of using an edible coating containing phenolic compounds of pomegranate peel cross-linked in the structure of aloe vera hydrogel was studied to extend the shelf life of sheep liver. Physicochemical (pH, peroxide index, total volatile nitrogen, thiobarbituric acid index and color parameters L*a*b*) and sensory (aroma, color, texture and overall acceptability) properties of the product in storage days of 1, 3 and 7 days and in the storage temperature of +4oC was evaluated. The results indicated that, the lowest value of monohydroperoxide formation (i.e. peroxide index) was observed in test samples coated with aleo vera gel containing phenolic compound of pomegranate peel extract that corresponding to the lowest total volatile nitrogen. Generally, in accordance to the results of sensory evaluation and quality tests, using of aleo vera gel containing bioactive compounds of pomegranate peel extract is recommended for shelf life extending of sheep liver.

Effect of osmosis dehydration, ultrasonic and edible coating as the pretreatment before drying has been studied in order to improve the flavor of the product, reduce thermal damages, decrease interstitial water and ease of transferring mass. The response surface method was used to optimize the drying conditions of Pommelo slices by osmosis-hot air. The concentration of edible coating (0-2% w/v) and the time of applying ultrasound (0-30 min) and the concentration of sucrose (40-80% w/w) were evaluated as independent variables on the amount of moisture content, absorption of solids, weight loss and productivity coefficient of Pommelo slices as dependent variables. All process variables were linearly significant for all responses (P<0.01). The comparison of the optimization results of coated and uncoated Pommelo osmotic dehydration showed that at the optimal point, the maximum amount of carboxymethyl cellulose coating and the osmotic dehydration time and the concentration of the osmotic solution in the coated sample were calculated as 2%, 21.86 minutes and 57.75%, respectively. The highest values of water reduction, weight loss and efficiency coefficient were 0.09172 (g/100g of solid matter), 0.091% and 19.478 respectively in the coated sample, and the highest absorption of solids with a value of 0.0089 (g/100g of solids) was reported in the uncoated sample. The results showed that the use of coating reduces the absorption of solid.

The quantity and quality of essential oil extracted from the plant is strongly influenced by the extraction conditions, so optimizing the extraction conditions can help us to achieve the most essential oil content with the best quality. Satureja sahendica Bornm. is an endemic medicinal plant of Iran, which is of great importance due to its high essential oil and thymol content. In this research, the effect of plant particle size (mesh size 12, 18 and 35) and the ratio of plant material to water (1:5, 1:10 and 1:15 w/v) on essential oil content and compositions of this plant were evaluated. The essential oils were extracted based on hydro-distillation method by Clevenger’s apparatus and then analyzed using GC/MS and GC/FID. The results indicated that the extracted essential oil decreased with the decrease in the plant particle size. The optimal ratio of plant material to water in order to obtain more essential oil was different depending on the plant particle size. The highest of essential oil content (2.15% v/w) was obtained from plant material with mesh size 12 in the ratio of 1:15 plant material to water. The number, type and amount of essential oil compounds were strongly affected by different treatments. The highest amount of thymol (81.79%) as the most important component of the Satureja sahendica essential oil was obtained from samples with mesh size 35 and a ratio of 1:10 plant material to water. Determining the most appropriate extraction conditions can be different depending on the purpose and desired chemical composition of the essential oil.

Peptides obtained from protein hydrolysis have many bioactive properties and have strong antioxidant activity against free radicals and prevent oxidation processes that cause damage to biological macromolecules and degradation and loss of food quality. Due to the large amount of rice production in the world, a large amount of rice bran is produced and available. As a suitable and cheap protein source, rice bran can be used for the production of plant-derived peptides. Optimizing conditions of enzymatic hydrolysis of rice bran protein by alcalase enzyme was done with the aim of achieving maximum antioxidant properties. In order to check the antioxidant activity of the obtained peptides, iron 3 reduction power tests and DPPH free radical inhibitory activity and total antioxidant activity were used. In order to optimize the process, Design Expert software and response surface method were used with three independent variables: enzyme concentration to substrate 1-3%, temperature 40-55 degrees Celsius and hydrolysis time 30-210 minutes. The optimal treatment was obtained under the determined conditions including temperature of 51.5 degrees Celsius, time of 131.5 minutes and concentration of enzyme to substrate of 3%, which has maximum DPPH free radical inhibition of 37.172%, total antioxidant activity of 1.109% and reductiveness of 2.084%. The obtained results showed that the hydrolysis process of rice bran protein by alkalase enzyme has led to the production of peptides with high and significant antioxidant properties that can be used in the production of useful foods and pharmaceutical industries and can also replace synthetic antioxidants.

The aim of this research was to produce a film based on mucilage of the flower of Paneerak modified with licorice root and copper sulfate nanoparticles. The D-optimal statistical scheme was used to study the antioxidant, antimicrobial, X-ray diffraction (XRD), Fourier transform infrared (FTIR), scanning electron microscopy (SEM), and thermal decomposition (DSC) properties of the films. The results showed that with the increase of licorice and copper sulfate nanoparticles, the antioxidant activity of the film increases significantly (p<0.05). The results of the antimicrobial activity of the prepared films showed that the addition of licorice and copper sulfate nanoparticles caused the antimicrobial activity of the film against Escherichia coli and Staphylococcus aureus. X-ray diffraction analysis shows that copper sulfate nanoparticles are physically combined with the mucilage polymer of Paneerak flower and it reduces the crystal structure. The results of Fourier transform infrared (FTIR) confirm the physical presence of copper sulfate nanoparticles in the polymer matrix and have electrostatic interaction with the polymer network. The results of the scanning electron microscope (SEM) show that the surface of films containing licorice root copper sulfate nanoparticles are more heterogeneous than the mucilage of Paneerak flower. Licorice and copper sulfate nanoparticles were able to delay the thermal decomposition of the mucilage of Paneerak flower and increase the thermal stability of the mucilage film.

Addition of nanoparticles of copper sulfate and licorice root to edible films based on mucilage of Paneerak flower improved antimicrobial, antioxidant, DSC and SEM.

The use of controlled fermented legumes along with the aqueous extract of aromatic plants is important in terms of improving the quality characteristics of wheat bread. In the present study, after spontaneous fermentation of mung bean sourdough containing saffron petal extract, the predominant lactic acid bacteria (LAB) isolate was used as a starter culture in controlled fermented sourdough, and then the characteristics of the produced wheat breads in terms of texture, surface expansion of fungi and overall acceptability were investigated. Sequencing results of PCR products led to the identification of Levilactobacillus brevis as the predominant LAB isolated from sourdough. Processing of wheat bread with mung bean sourdough containing mentioned bacteria and saffron petal extract not only improved the textural features and overall acceptability of the produced bread, but also increased their resistance towards the surface expansion of Aspergillus niger. Based on the results, wheat bread containing fermented mung bean and saffron petal extract showed the best textural features compared to other samples with crumb hardness of 10.21 N and porosity of 16.16%. Furthermore, the mentioned sample with 44.33% inhibition had the highest ability to inhibit the growth of the indicator fungus compared to other samples. Although the use of mung bean and saffron petal extract alone in the formulation of wheat bread did not show a great effect on reducing the surface expansion of fungi, but their combined application was significantly (P<0.05) effective in reducing the surface growth of fungus. Due to the appropriate techno-functional capabilities of controlled fermented mung bean sourdough containing saffron petal extract, it can be used as a natural improver in the bakery industries.

The sprouting process includes changes in nutritional, biochemical, and sensory characteristics that improve chickpea quality and increase its digestibility. Various products such as Falafel are made from ground and dried chickpea sprouts. Therefore, in this research, the use of hot air (70°C), infrared (250 W), and microwave (220 W) methods for drying ground chickpea sprouts was investigated and modeled. The drying time of the samples in the infrared dryer was shorter than the other two dryers. The average drying time of the samples in the hot air, infrared and microwave dryers was 63.3, 26.7, and 156.7 min, respectively. In this research, the effective moisture diffusivity coefficient of ground chickpea sprouts in hot air, infrared and microwave dryers was determined to be 4.99×10-9 m2s-1, 17.95×10-9 m2s-1, and 1.59×10-9 m2s-1, respectively. To study the drying kinetics of ground chickpea sprouts, Wang and Singh, Henderson and Pabis, Approximation of diffusion, Page, Newton, Midilli, and Logarithmic mathematical models were fitted to the experimental data. Finally, when modeling the drying process of this product, Midilli's mathematical model with four parameters was chosen as the best model due to its minimal error.

Herbal bioactive compounds are secondary metabolites of plants that are produced in response to environmental stress and to protect the plant against harsh conditions. These compounds have both health effects on humans and also have preservative effects in food products. The conditions for extracting active compounds have a significant effect on their functional activities, and conventional and new methods have been used to extract bioactive compounds from plants. The aim of this study was to compare the extraction methods of bioactive compounds of Persian Golnar extract (PGE). In this research three methods of ohmic (temperatures of 45 °C and 60 °C for 40 and 60 min), ultrasonic (temperatures of 40 °C, 50 °C and 60 °C for 20 and 40 min) and perculation (for 24, 48 and 72 h) were used to prepare PGE, and the best extract was selected based on the extraction yield, total phenol content (TPC), total anthocyanin content (TAC) and antioxidant activity (DPPH radical scavenging). The results showed that there was no significant difference between the extraction yields of all three methods (p>0.05). The ohmic method had the same TPC as the ultrasonic method, but showed a higher TAC and antioxidant activity and was chosen as the best method. The optimal treatment in this stage included ohmic method, 60 °C and 40 min, and the extract obtained under these conditions contained 109.74 mg GAE/g of TPC, 373.26 mg/g of TAC and 81.11% antioxidant activity.

Adding copper nanoparticles and rosemary essential oil can improve the structural and mechanical properties of films based on fenugreek seed mucilage and eggplant skin powder. The aim of this study was to prepare edible films based on mucilage of fenugreek seeds and eggplant skin powder containing copper nanoparticles (0, 2, 4% w/w) and rosemary essential oil (0, 4, 8% w/v). Edible films were prepared based on mucilage of fenugreek seeds and eggplant peel powder, and copper nanoparticles (0, 2, 4%) and rosemary essential oil (0, 4, 8%) were added to it. The structural and mechanical properties of the prepared films were investigated. According to the obtained results, increasing the amount of copper nanoparticles and rosemary essential oil in the film decreased the mechanical properties of the films. According to the obtained results, increasing the amount of copper nanoparticles and rosemary essential oil in the film decreased the mechanical texture of the films. X-ray diffraction (XRD) analysis showed that copper nanoparticles were physically combined with fenugreek seed mucilage polymer and eggplant skin powder, resulting in the strengthening of the crystal structure. Fourier transform infrared (FTIR) results confirmed the physical presence of copper nanoparticles in the polymer matrix. The results of the scanning electron microscope (SEM) showed that the surface morphology of the nanocomposite film is heterogeneous compared to fenugreek seed mucilage and eggplant skin powder. Exposure of the prepared detector film to different pHs led to the change of the color of the films from red to yellow. These color changes of the films were consistent with the color changes of the anthocyanin solution. The addition of copper nanoparticles and rosemary essential oil to edible films based on fenugreek seed mucilage and eggplant skin powder improved the Fourier transform infrared (FTIR) of the films, and also weakened the mechanical properties.

In this study, the effect of microwave pretreatment at the power of 500 and 900 W on the antioxidant properties (DPPH radical scavenging activity and total antioxidant capacity) of flaxseed protein hydrolysate was investigated in the period of 30-210 minutes. In the next step, the effect of different concentrations (20-100 mg/ml) of the optimum treatment on the antioxidant properties (total antioxidant capacity, Fe reducing power, DPPH radical scavenging activity and Fe chelating activity) was investigated and was compared with the antioxidant capacity of vitamin C as a synthetic antioxidant and unhydrolyzed flaxseed protein. The results showed that microwave pretreatment at a power of 500 W significantly increased the antioxidant properties (DPPH radical scavenging activity and total antioxidant capacity) of flaxseed protein hydrolysate, but higher microwave power (900 W) led to reduction of antioxidant activity in comparison to the sample without pretreatment or the sample with microwave pretreatment with a power of 500 W. The sample with microwave pretreatment with a power of 500 W and hydrolysis time of 180 minutes was selected as the optimum treatment with the highest total antioxidant capacity and DPPH radical scavenging activity. Investigating the effect of concentration on the antioxidant properties of hydrolyzed protein showed that the highest DPPH radical scavenging activity (52.7 %), total antioxidant capacity (1.35 absorbance at 695 nm), Fe reducing power (0.859 absorbance at 700 nm) were achieved at the concentration of 60 (mg/ml) and the highest Fe chelating activity (50.83%) was obtained at the concentration of 80 (mg/ml). As a result, the flaxseed protein hydrolysate with considerable antioxidant capacity, can be used in the production of functional food products, nutritional supplements for athletes and the elderly.