دکتر محمدحسین عزیزی تبریززاد

Advanced glycation end products (AGEs) are a group of compounds formed during the Maillard reaction, which can have adverse effects. This study aims to investigate the formation of fluorescent AGEs using the response surface method (RSM). Factors such as protein type ((whey protein 2.0, 3.5, and 5.0 %w/v) and casein (1.0, 2.0, and 3.0 %w/v)), three types sugar ((glucose and frouctose (0.2, 0.6, and 1.0 M) and lactose (0.1, 0.3, and 0.5 M)), and pomegranate peel (PPE) concentration (250.0, 500.0, and 750.0 ppm) along with their interactions are analyzed. The results of this study showed that, the type of protein, type of sugar, and concentration of phenolic extract from pomegranate peel were effective in preventing the formation of AGEs, and the pomegranate peel extract (specially at 750.0 ppm) was able to effectively prevent glycation reaction. According to the results, protein type and concentration significantly influence AGEs formation. The inhibitory activity of the extract in the model system containing casein was lower than the system containing whey protein, and overall, the inhibitory power decreased with an increase in protein concentration. By changing the type of sugar present in the model system, the inhibitory behavior of the pomegranate peel extract became complex, showing increased, decreased, or no effect in some cases. Further investigations can suggest the use of this extract, especially in the formulation of food products, including infant formulas.

Plasticizers in plastic packaging materials, including terephthalate esters, can migrate into foods during storage, which can lead to safety and sensory food quality issues. In this study, the total migration rate of terephthalate esters from PET bottles into carbonated malt beverages was investigated at temperatures of 5, 20, and 40 °C during 30 days of storage in an acidic food simulant (acetic acid 3%). The total migration rate was evaluated after 10, 20 and 30 days. The data were in accordance with the Arrhenius equation, and the activation energy was studied at the above temperatures. The results showed that the migration process increased with increasing time and temperature. Changing the temperature from 5 to 45 °C significantly increased the diffusion coefficient of the migrating component (p < 0.05). The data had a good fit with the Arrhenius equation, and this model explained the dependence of the diffusion coefficient on temperature. A significant increase in activation energy was observed with increasing temperature. Migration of heavy metals under severe test conditions (40 °C during 30 days’ storage) showed that the migration rate of metals (Cr, Pb, As, Hg and Cd) was lower than the value specified by the European standard. In general, it can be said that the obtained data prove the safety of PET packaging containers for carbonated malt beverages, since the refrigerator temperature is the usual storage temperature for carbonated malt beverages.

In this study, the effect of microencapsulated grape extract in chitosan nanoparticles (0.5:1 ratio) on surimi prepared from Kilka fish was investigated.  Physical properties of nanoparticles (particle size, zeta potential, and PDI) were 177.3 nm, +32.94 mV  and   0.405 respectively. Also, morphological characteristics  (SEM photo) were  studied and the data showed that the produced nanoparticles were in a favorable condition. After preparation of surimi from Kilka fish, treatments included: Surimi (control)   Surimi containing chitosan-surimi  nanoparticles containing extract and surimi  containing chitosan nanoparticles and extract were prepared and chemical factors of deterioration in surimi (pH,  TVB-N,  TBA  and peroxide) were evaluated on different treatments days (0, 1, 3, 6 and 9) at refrigerator temperature. Also, sensory evaluation of treatments was done  after cooking  by hedonic method. The results showed that the changes in the chemical factors mentioned in the treatments containing chitosan nanoparticles and extract were reduced (p˂0.05).   Sensory evaluation of the use of chitosan nanoparticles along with extract showed a decrease in taste, odor and overall acceptance factors by the consumer. According to the results, The use of chitosan nanoparticles containing extract in surimi of Kilka fish can delay the deterioration of surimi and increase the shelf life of the product and improve organoleptic properties during refrigerated storage.

Considering the sensitivity of fish meat to rapid spoilage, storage conditions and type of packaging are very effective factors in maintaining its quality and nutritional value after catching. In this research, rainbow trout fillets packed with aluminum and polystyrene as treatment and polyethylene bag as control were kept at 4°C for 12 days. Physical, chemical and microbial factors of fillets by recording changes in moisture, total protein, fat, total ash, free fatty acids, peroxide (PV), pH, Thiobarbituric acid (TBA), Total Volatile Basic Nitrogen (TVB-N) and also total microbial load It was measured. The results showed that with the passage of time, moisture and fat decreased significantly. Total protein, total ash, free fatty acids, PV, TBA, TVB-N and total microbial load increased significantly during storage. Also, pH had an increasing trend, but this increase was not significant. The highest amount of TVB-N on the twelfth day was related to the control package with a value of 24.52 mg/g. The lowest amount of total microbial load on the twelfth day was related to aluminum packaging with a log value of 6.86 cfu/g. According to the results, the priority of using packaging to increase shelf life and maintain the nutritional value of fillets was first with aluminum packaging and then with polystyrene. The polyethylene bag was declared unrecommended for consumption due to the lack of nutritional value and reduced product quality. Aluminum packaging worked significantly in maintaining the physicochemical and microbial properties of the product and according to the declared permissible limits of TVB-N and total microbial load, which are important indicators of spoilage, only fillets packed with aluminum containers could be consumed until the end of the storage period.

In this study, the effect of an aqueous extract of grape microencapsulated in chitosan nanoparticles (0.5 / 1) was used to evaluate the shelf life of surimi prepared from Kilka fish by ionic gelation method.

Grape was extracted aqueously, and total phenol content was detected by spectrophotometry and phenolic acids of the extract by HPLC method.  Physical properties of nanoparticles including particle size, zeta potentia and PDI were determined with zeta-sizer, and microencapsulation efficiency was determined by spectrophotometer and loading capacity of nanoparticles by HPLC method. Antioxidant activity of free extract and chitosan nanoparticles with / without extract (by DPPH test) was determined.  The total count was determined by cryophilic, mesophilic, pseudomonas, mold, and yeast and inhibition capacity (MIC, MBC and IZ) of selected Gram positive and Gram negative bacteria and mold and yeast in different treatments days (0 , 1 , 3 , 6  and 9 ) at refrigeration temperature.

The data showed that the produced nanoparticles were in a favorable condition (particle size, zeta potential and PDI: 177.5 nm, +32.95 mV and 0.385 and the efficiency of microencapsulation and loading of nanoparticles were 48.95 and 6.19 percent, respectively). The phenolic content of the extract was 2896 ±18 mg/g and the extract in the loaded state showed a higher percentage of antioxidant activity (42.1%). Growth inhibition in microorganisms (gram positive and negative) is also increased and the overall amounts of bacteria and mold and yeast decreased, and the total values of cryophilic bacteria (6.35 ± 0.29 CFU/g), mesophilic bacteria (6.18 ± 0.27 CFU/g), Pseudomonas (5.41 ± 0.14 CFU/g), and mold and yeast (2.45 ± 0.26 CFU/ /g) in the last day of experiment, showed a significant decrease in the growth of microorganisms.   

According to the results, the use of chitosan nanoparticles containing extract in surimi of Kilka fish can delay microbial decay and increase the product resistance to free radicals and thus increase the shelf life of the product during the storage period in the refrigerator.

The health-conscious public demands high-quality and low-calorie products that are low in fat and sugar. The aim of this research is to evaluate the physicochemical characteristics of gluten-free cup cake containing inulin. In this research, rice, white bean and chia flours are used as a partial substitute for wheat flour, respectively at the levels of 50, 40 and 10 grams, inulin as a fat mimics at the levels of 0 and 30 grams, and sucralose as a partial substitute for sugar in the cake is used at the levels of 0 and 0.05 grams. According to the results of this study, sugar substitution with sucralose and fat replacement with inulin in gluten-free prebiotic cake, reduced moisture content, brighter and yellower crust and crumb, decreased pH, increased hardness and decreased springiness and cohesiveness.

Due to the importance of bread in the diet of the worldchr('39')s people, it is vital to pay attention to increasing the nutritional properties of this product. In order to reduce the content of phytic acid and increase the shelf life, in this study, an attempt was made to investigate the effect of microencapsulation of amylase and phytase enzymes in bread. Chemical, physical, microbial, and sensory properties of whole-grain toast containing microencapsulated enzymes and free enzymes toasts were compared with the control sample (whole-grain toast and no enzyme). The results showed that samples containing free and encapsulated enzymes had less Phytic acid than the control sample (p≤0.05). The specific volume and porosity of the samples containing free and microencapsulated enzymes were higher, and their viscosity was lower than the control sample (p≤0.05). Samples containing enzymes had the lowest brightness, redness, and yellowness parameters than the control (p≤0.05). Control samples had lower numbers of mesophilic bacteria, mold, and yeast, and the samples containing the microencapsulated enzyme showed the highest sensory score by the fifth day of the test (p≤0.05). The results showed that encapsulated enzyme had a higher amount of phytic acid than the sample containing free enzyme. However, in other results, there was no difference between the microencapsulated and free samples, and the use of microencapsulated enzymes during storage led to Increasing the score of sensory properties, and it can be used to increase the quality of toast containing bran.

Foxtail millet contains amounts of nutrients such as starch, protein, vitamins and minerals. The aim of this study was to investigate the physicochemical properties of refined wheat flour (RWF) replaced by different ratios of foxtail millet flour (FMF) from 10% to 30%. The composite flour samples were analyzed for proximate composition, color, falling number, wet and dry gluten content, damaged starch content and alveo-consistograph characteristics. Correlation coefficients between flour analytical parameters and alveo-consistograph characteristics were obtained. Crude fiber, fat, protein and ash content increased not significantly (p>0.05) with increasing the amount of FMF. No significant difference (p>0.05) of b* value was observed between the flour samples. Adding the FMF, not significantly reduced (p>0.05) falling number, damaged starch content, wet and dry gluten content. Consistograph test indicated that addition of the FMF decreased water absorption capacity, maximum pressure and tolerance, however, drops in pressure at 250s and 450s became greater. Alveograph test revealed that with adding FMF, dough resistance to extension and dough strength decreased but an increase in dough extensibility obtained at FMF30%. The results of rheological properties by alveograph indicated the rate of the FMF influenced the rheological behavior.

Starch is one of the important plant storage carbohydrates that has many applications as a raw material in different industries especially the food industry. In this study physicochemical properties of starches extracted from quinoa TTKK and wheat, Pishgam were investigated. Percentage of amylose, X-ray diffraction, swelling power, solubility, water, and oil absorptions, and thermal, pasting, and textural properties were measured. SEM images illustrated that wheat starch granules size were about 8-10 μm and quinoa starch granules size were about 2-5 μm. Results showed that the percentage of quinoa starch amylose (9.19 ± 0.83) was lower than wheat starch (19.57 ± 0.66) but crystallinity percentage was higher in quinoa starch(p<0.05). As well as water absorption. Regarding thermal properties, all the parameters were higher than wheat starch. Measurement of starch pasting properties demonstrated that quinoa starch had higher pasting temperature and lower peak, final, break down, and set back viscosity(p<0.05). Studies on textural properties showed that hardness, gumminess, and springiness were significantly lower in quinoa starch compared to wheat starch. Therefore, unique starch properties of quinoa make it possible to use it in various bakery products which a lot of mechanical forces are applied to produce. as well as frozen products.

In this study, PET-CMC bilayer nanocomposites films containing different levels of zinc oxide nanoparticles (ZnO NPs; 0%, 1%, 2%, 3%, 4%) were prepared and characterized. For better attachment of CMC on Polyethylene terephthalate (PET), atmospheric plasma pretreatment was used. The water vapor permeability, moisture, mechanical and microbial properties of the films were analyzed. Also, in order to investigate the effect of plasma treatment on improving the properties of bilayer films, a comparison was made between plasma treated and untreated bilayer films using FTIR test.  Results showed the formation of polar groups such as C=O and OH on the PET surface following the plasma treatment which improved the adhesion of the two layers of polymer to each other. The water vapor permeability of PET-CMC films containing ZnO NPs decreased compared to the pure film with increasing the ZnO NPs percentage. Increasing the nanoparticles percentage had a positive impact on the tensile strength and increased this factor from 123.77 to 466.80 MPa, while the elongation at break decreased from 48.38% to 10.59%, and the nanocomposite films were revealed more resistant compared to the pure PET-CMC film, which facilitates the transport and storing of the foodstuffs. In addition, the presence of ZnO NPs in PET-CMC films exhibited antimicrobial activity against Escherichia coli and Staphylococcus aureus. In general, this research verifies improvement in physical, mechanical, and microbial characteristics of PET-CMC nanocomposite films along with the increasing of ZnO NPs. Our findings suggest that plasma-treated PET/CMC films have the potential for application in food antimicrobial packaging and can extend the shelf-life of packaged food as active packaging.

Today, saturated and trans fatty acids are one of the most important potential health limitations of consuming prepared foods. Fast foods are widely consumed by adults and children due to their quick preparation and the popularity of the taste. As a result, it is very important to control the amount of saturated and trans fatty acids in fast foods. The city of Tehran was divided into five regions: north, south, west, east and center, and from each region, three types of fast food, including mixed pizza, falafel and Chicken nuggets, and three samples from each fast food (a total of 45 samples from 45 different grocery stores were randomly selected). In this study, the concentration of trans fatty acids was calculated as a percentage by Agilent7890A gas chromatography. The average of saturated fatty acids in falafel fast food, mixed pizza and chicken nuggets were 18.02, 36.35 and 19.11 g / 100g, respectively. The average trans acids of chicken nugget fast food, mixed pizza and falafel were 0.36, 0.71 and 0.06 g / 100g, respectively. The difference between different regions of Tehran was not significant in terms of saturated and trans fatty acid content (P> 0.05). Consumption of trans fatty acids through fast food in Tehran is appropriate in comparison with international standards. The lower risk factors than the global standards in this study is due to the low per capita consumption of fast food in Iran (IR = 4 g / day).

Encapsulation with polysaccharides is one of the new methods for increasing the stability of bioactive compounds and improving the viability of probiotics during food processing and storage. In this study, due to the high benefits of probiotic products on human health, the effect of Lactobacillus plantarum encapsulated by chitosan, tragacanth gums and their combination in a concentration of 1% (w/w) on the physicochemical and overall acceptance of pineapple juice were evaluated during 30 days storage in the refrigerator. The results showed a decrease in pH and an increase in the acidity of all samples (P<0.05). In addition, the viability of Lactobacillus plantarum was increased in the treatment encapsulated by the combination of chitosan and tragacanth gums so that, the number of viable bacterial cells was higher than 6 log cfu/ml on the 30th day of storage. The formalin index increased between the 20th and 30th days of storage in all samples (P<0.05). Also, the highest overall acceptance was belonged to the sample containing the Lactobacillus plantarum encapsulated by chitosan (P<0.05). The results showed that pineapple juice is a suitable substrate for the growth of Lactobacillus plantarum and it can be considered as a carrier for the transmission of probiotic strains to the human body. Moreover, those with special nutritional needs can take advantage of probiotic pineapple juice, including lactose and cholesterol deficiency as well as richness in mineral substances.

Chocolate is one of the foods that has special place among people and most of the people consume this energetic food. If this product has got the health effects section, it will be noted more than the past. Therefore, using foods, which have more health benefits than cocoa, in formulation and preparation of chocolate, will make glowing future for this product. One of the effective approaches in this field is the carob pod powder. In this research, Chocolate samples with replacement levels of 25, 50, 75, and 100 percent along with standard sample were produced and effects of substitution of cocoa powder by carob pod powder on physicochemical, textural and rheological properties of dark chocolate was investigated. Increasing levels of carob pod powder in the formulation, compared with the standard, gave the products lighter color. Outcomes of investigating the hardness of the products indicated that, samples containing higher amounts of carob pod powder, have less textural hardness, which can be because of the particle size distribution and the fibrous properties of the carob pod powder. About rheological models, it was found that the Herschel- bulkly model was the best fit model for the chocolate samples. Chocolate samples were assessed for sensory acceptance by a hedonic scale, samples containing 25 and 50 percent of carob pod powder had the highest acceptability even more than the standard. The results proved that it is possible to utilize carob pod powder to replace cocoa powder in chocolate production in order to improve nutritional values with agreeable sensory attributes.

Production of bioactive peptides from wheat gluten by Biarum carduchcorum extract and the biological and functional capacity were investigated in the present study. Results showed that Biarum carduchcorum have the highest protease activity in (5, 45) pH and temperature, respectively. All fractions obtained (F1:˂3, F2: 3-30, F3: 30-100, F4> 100 kDa) exhibited antioxidant activity, However F1 registered the highest DPPH scavenging activity (65.85±2.64 µmol TE/g) and reducing power ABTS (295.81±2.05 µmol TE/g) and F4 have the lowest antioxidant activity. The highest ACE-inhibitory activity was F2 (86.3%) and F3 (76.3%). F1 Fractions showed an appropriate inhibitory effect on tested bacteria while total extract of F4 had no inhibitory activity against pathogens. Functional properties suggested that the solubility of hydrolysates in all samples decreased in acidic pH but as molecular weight of hydrolysates fractions increased, solubility of hydrolysate in pH (4, 7) increased significantly. Emulsifying activity index decreased and foaming and emulsion stability index increased. It seems that hydrolysates of gluten, by-product of starch industry, have a good potential biotechnological alternative for the industry.

In this study, an ultrasonic-thermal concentrator under vacuum conditions was fabricated and the effect of concentration variables for watermelon juice concentration was optimized. Concentration temperature process in three levels (40, 50 and 60°C), vacuum pressure in three levels (20, 40 and 60kPa) and ultrasonic waves power in three levels (36, 60 and 84W) were conducted. Statistical analysis of data and optimization of concentration process were performed using response surface method and central composite design. Results showed that the increase of concentration temperature has a positive effect on concentration process time and total energy consumption and negative effect on lycopene content and the total color difference. Decrease of vacuum pressure to caused increased lycopene content and decrease the total color difference, concentration process time and total energy consumption. Also increased ultrasonic waves power caused increase in lycopene content, total color difference, total energy consumption and decrease in concentration process time. Optimization of watermelon juice concentration point was obtained on concentration temperature 40°C, vacuum pressure 20 kPa and ultrasonic waves power 46.5W. Optimal values of response variables in this condition include lycopene content, the total color difference, concentration process time and total energy consumption in equal order 238 mg/kg, 25.7, 94.5 min and 0.727 kWh. The use of ultrasound waves along with the concentration temperature and vacuum pressure could have positive results on the watermelon juice concentration process.

Physicochemical characteristics, viability of probiotic bacteria, and sensory specification were investigated during three weeks of refrigerated storage with various concentration of oat bran extract and carbon dioxide in orange flavor beverage. It was observed that the acidity of the beverage samples significantly increased by increasing the percentage of oat bran extract and carbon dioxide, while the Brix decreased. The viability of the bacteria was significantly enhanced by increasing the amount of carbon dioxide and oat bran extract concentration until the 14th day after fermentation. The viability extremely decreased with increasing the storage time to 21 days. Oat bran is a rich source of nutrients including carbohydrates, protein, minerals, vitamins and soluble β-glucan. The use of oat bran as a profitable substrate to produce a non-dairy orange flavor probiotic beverage was examined. Due to high viability of the Lactobacillus acidophilus after two weeks of storage at 4 °C, the formulation was characterized with 15percent (w/v) oat bran extract and 1percent carbon dioxide. The highest sensory score was obtained by 10percent (w/v) oat bran extract and 0.5percent carbon dioxide sample. Therefore, incorporation of the oat bran in formulated orange flavor probiotic could enhance the nutritional value of the beverage.

The present study aims to investigate replacing sugar with 0, 25, 50, 75 and 100% grape syrup in producing sponge cake and its effect on properties such as texture stiffness, volume, density, and porosity during 7 days after production. The results demonstrated that increasing grape syrup percentage in the cake samples changed their properties significantly. The samples containing 50 and 100% grape syrup had the most density, and  least stiffness, and  most volume, respectively. Comparing the mean of treatment effect in day suggested that the most stiffening occurred in seventh day. In addition, the sample containing 25% grape syrup has the most porosity. The mean and standard deviation of treatment effect of the blank indicated that the stiffening of all the samples  increased compared with the blank. Thus, there is a significant statistical difference between the samples in this regard. Therefore, the sponge cake prepared by 100% replacement of sugar with natural sweetener (grape syrup) could be introduced as the best sample because of having   the most volume,  least stiffening amount, more desirable taste and appearance.

Pasta is one of the most popular foods consumed in the world because of its low price, easy cooking and good taste. It is rich in calories (complex carbohydrates), but it is poor in dietary fibers, minerals, phenolic compounds and vitamins. Due to the limited number of raw materials in pasta production, its popularity among all segments of society as well as the simple production process, it can be used as a suitable carrier for enrichment. In this study, the effect of pasta enrichment using fruits and vegetables on physicochemical and nutritional properties of the pasta was investigated. The results of this study showed that the addition of vegetables and fruits to formulation of past considerably increased content of bioactive compounds such as phenolic compounds as well as antioxidant activity. In between pasta production steps, pasta cooking had the most impact on the reducing of bioactive compounds. Vegetables and fruits can leach into boiling water (cooking water) or can be thermally degraded. The enrichment has a dilution effect of the gluten network, leading to changing of cooking and texture properties. Due to the type of compounds added to the pasta formulation, their effect on glycemic index was different. Therefore, enrichment is successful only if processing conditions are optimized to keep in the final product the desired nutritional characteristics of the vegetables and fruits