مجله علوم و صنایع غذایی ایران
سال بیستم شماره 4 (پیاپی 137، تیر 1402)

The present research aimed to evaluate the effects of roasting and microwave thermal processes along with pH change on the amount of residues of three commonly used antibiotics, enrofloxacin, oxytetracycline and sulfadiazine in chicken meat. For this purpose, first the three antibiotics were added to the chicken meat samples in amounts 4 times the remaining limit. Meat samples containing residues of each antibiotic were subjected to roasting (at 200 °C for 30 minutes) and microwave (at 100 °C for 3 minutes) treatments at pH 5.8 and 4.8. Then, the residual amount of each of the antibiotics was investigated by high-performance liquid chromatography (HPLC) along with colorimetry and evaluation of cooking loss. The results showed that both treatments were able to significantly reduce the amount of antibiotic residues, but both processes were more effective at pH 4.8 than 5.8 (P<0.05). The highest amount of reduction of antibiotic residue at pH 4.8 in both microwave and roasting treatments was observed in oxytetracycline residue with 76.2 and 72.4% respectively. Roasting and microwave treatments decreased L* index, but a* index decreased in roasting and increased in microwave, and b* index increased in microwave, but there was no significant change in roasting. Also, the amount of cooking loss in roasting in the range of 58 to 71% was more than that of microwave in the range of 48 to 62% (P<0.05). Finally, microwave treatment can be introduced along with reducing the pH of chicken meat to 4.8 as the best treatment to reduce antibiotic residues.

Frankincense is a resinous gum obtained from some species of the Boswellia genus. The use of frankincense for food and medicinal uses dates back to more than five thousand years ago, but despite its importance and application, only 27-35% of it is soluble in water. As most frankincense gum is insoluble, this research used the response surface method to study the effect of different chemical modification conditions (NaOH concentrations (X1), reaction temperatures (X2), and MCA concentrations (X3)) on increasing the solubility percentage. The results of the optimization process of the chemical modification of frankincense gum indicate that the conditions of maximum solubility are equal to 85.49, with a desirability rate of 0.97. Therefore, the concentration of NaOH and MCA equal to 0.048, 0.01 mol, and a temperature of 75 degrees Celsius chose as the best optimization conditions. In addition, the intrinsic viscosity and molecular weight of the native gum were higher than the modified gum under optimal conditions. There is a significant difference between the apparent viscosity of natural gum (18.02 ± 0.726 mPa.s) and modified (17.36 ± 0.681 mPa.s) (p>0.05). The results indicate that native and modified gum in optimal conditions show a shear thinning behavior with increasing shear rate, and their behavior is similar to pseudoplastic. The colorimetric test with image J software indicated that carboxymethylation of frankincense gum led to significant changes (P < 0.05) in the total color difference factor (ΔE) and whiteness index (WI), L*, a*, and b*factor.

Soybean meal is one of the sources of vegetable protein, which together with wheat flour proteins, can provides a complete source of amino acids for the human body, so using it in bread can help to solve protein deficiencies. For this purpose, to prepare Barbari bread containing soy meal, a combined design containing a group of mixing variables, including different levels of transglutaminase enzyme (0 to 1 %), soybean meal flour (0 to 50 %), wheat flour as filler (0 to 100 %) and a process variable including ultrasonic altitude (0 to 100%) was used and physicochemical and sensory characteristics including total ash, pH, moisture, porosity and taste, texture and color scores were investigated. The results showed that transglutaminase enzyme and ultrasonication have a significant effect on physicochemical properties and porosity (P<0.0001). The significant increase in color score of the samples was due to the positive and significant effect (P<0.0001) of soybean meal on that characteristic. The porosity of the samples was significantly affected (P<0.0001) by the interaction of enzyme and ultrasound. Finally, in order to obtain samples with the highest porosity and color, taste and texture scores, it is suggested to use the mixing ratio of soybean meal flour 33%, enzyme 1%, wheat flour 66% and ultrasound altitude 100%.

Accurate food labelling is of utmost importance for fair trade and empowering consumers to make knowledgeable choices. Quantitative assessment of the meats is one of the most important factors in authentication of this meat product. Therefore, the purpose of this research was the efficiency of the stereological method for detection of the percentage of meat used in raw (Hamburger) and heat-treated (Sausage) meat products. In this study, three samples of beef burger (containing 30, 60 and 90 % meat) and sausage (containing 40, 60 and 90 % meat) were prepared. Each sample was flattened, and then fractionator sampling using a perforated plate as a cutting guide was used for getting systematic uniform random blocks. Totally, 12 blocks were taken from each sample. Each block was fixed in 10 % neutral formalin and embedded in paraffin. The obtained samples, after preparation of tissue sections and staining using haematoxylin and eosin (H&E), were studied by a light microscope. The data were analyzed using one-way ANOVA statistical method and t-test was used to compare significance difference between groups. Stereological analysis showed that the estimated meat percentages in beef burger in different percentages (30, 60 and 90%) did not have a significant difference with the real percentages of meat. In the case of sausage, there was significant difference between the estimated meat percentages and the real percentages of meat in different samples of sausage. Stereology method can be a suitable complementary method to detect the amount of meat used in raw meat products.

The aim of this research was to evaluate the effect of polyethylene (PE) films coated with menthol and carvacrol on the physicochemical, microbiological, and sensory properties of low-moisture Mozzarella cheese. At first, PE films were coated with MC-HPMC solution containing different concentrations of menthol and carvacrol (0, 1, 1.5 and 2%), Mozzarella cheeses were then packed with these active films, and physicochemical, antimicrobial, and sensory properties of cheese treatments for 30 days storage in refrigerator were studied. The results showed that over time, the pH and moisture amount of all treatments significantly were decreased, whereas, the acidity and hardness amounts of cheeses were increased, but their exchange rate in control significantly was higher than other samples (p<0.05). Packaging of cheeses with active PE films leads to decrease the growth rate of mesophyll bacteria and molds and yeasts in cheeses. At the end of storage period, the lowest number of molds and yeasts and microbial load were for samples packed in films containing 2% menthol and carvacrol. From the point of E. coli and S. aureus contamination, the samples packed in active films were safe until the last day of storage (30th days), while control sample was incredible at 17th of storage. Packaging of Mozzarella cheese in PE films containing different levels of menthol and carvacrol also leads to improved sensory acceptance of cheeses during refrigerated storage. Finally, the results demonstrated that coated PE films with solutions containing menthol and carvacrol active components had a positive effect on the extension of the Mozzarella cheese shelf life, especially, at 2% concentration.

In this study some physical and geometrical properties of 11 superior apricot genotypes were determined. These properties such as respiration rate, fruit dimensions, perimeter, surface area, volume, compact factor, geometric mean diameter, projected area, shape factor, circularity, length to width ratio, length to thickness ratio, and length to mass ratio were measured at harvesting moisture content ranging from 75.19 to 87.67 %. Then the correlation among average values of the attributes was performed and the genotypes were classified using principal component analysis (PCA). The results showed that all the genotypes had significant differences in terms of all the studied attributes (P<0.01). There was a significant and positive correlation between fruit length and weight and fruit length and moisture content. Fruit shape factor and compression factor showed a positive and significant correlation, while these attributes had negative and significant correlations with circularity. This study showed that Iranian apricot genotypes could be discriminated by differences in their geometrical characteristics using principal component analysis. Based on the PCA results, the first two components account for the most of the variation in the data (91%) and five distinct groups were observed. Overall, the results of this study can be beneficial for the design of equipment for harvesting, transportation, separating, packaging, and processing of apricot fruit.

Rainbow salmon is one of the species with commercial value and is one of the farmed fish belonging to cold and clear waters, and it is of great importance in terms of having optimal nutritional compounds. For this purpose, to extract protein from fish by pH-shift method, (pH = 3.5) acid treatment and (pH =10.5) alkaline treatment were used, and two groups of acid and alkaline treatments were at the levels of 0.5%, 1% and 1.5%. It was added to cow's milk and then physicochemical characteristics such as moisture percentage, pH, acidity, protein content, fat content, microbial count, textural properties (hardness, cohesiveness, stickiness, chewability and gumminess), color and sensory indicators ( (such as smell, taste, texture, consistency and overall acceptance) of the cheese samples were evaluated. The results showed that by adding different percentages of acid and alkaline treatment protein, moisture content and acidity, fat, redness index (a*) and lightness (L*) of the samples decreased and protein and pH of the cheese samples enriched significantly increased (P≤0.05). Also, the count of coliforms was less than the defined limit, and the total amount of forms in samples enriched with acid treatment was lower than alkaline treatment. In the samples of cheese enriched with acid and alkaline treatment protein, the degree of hardness, stickiness, cohesiveness, gumminess and chewability of the samples increased significantly. Iranian white cheese is one of the most important and widely consumed milk dairy products, and in order to enrich and improve its physicochemical, sensory and textural characteristics, various methods are used. Among the proteins of rainbow salmon, it is more interesting due to its favorable nutritional characteristics.

Shelf life increasing of red meat has the great importance due to its perishable properties and consumers' demand to use food free synthetic preservatives. This study was aimed to investigate the antimicrobial and antioxidant effects of poly lactic acid film (PLA) containing different concentrations of ethanolic sumac extract (SE 1 and 3%) and copper oxide nanoparticles (CuO1 and 2%) on shelf life enhancement of the minced beef during cold storage. The samples were stored at 4 ± 1 °C for 12 days and analyzed at 0, 1, 3, 6, 9 and 12 days of the storage period. All of the treatments significantly (P≤0.05) decreased total viable count, psychrotrophic bacteria and Enterobacteriaceae spp. population as compared control group during the storage period. Total volatile basic nitrogen (TVB-N) and pH values of the non-packed samples (control) were significantly (P≤0.05) higher than the packed ones during the storage time. The combined treatments containing SE and CuO-NPs showed the highest efficiency in shelf life increasing of the cold stored minced beef in dose dependent manner. Based on the results, it can be concluded that the usage of biodegradable poly lactic acid film containing a complex of SE and CuO-NPs is effective packaging in the shelf life improvement of minced beef during 12 days of the refrigerated storage period.

The consumer demand to use natural preservatives in food products instead of synthetic ones and awareness about not using plastic is increasing. In this research, chitosan-potato starch film containing celery seed extract was prepared at different concentration levels (0.5, 2 and 8%) and the physical properties of the film (thickness, moisture content and solubility), mechanical properties and antioxidant activity also determined. Then, the chicken fillet wrapped by the film was kept in the refrigerator for 15 days and the microbial growth and primary and secondary oxidation compounds formation with peroxide value and thiobarbituric acid and sensory evaluation was also monitored during the storage time. The results showed that the total phenol and flavonoid content of celery seed extract was 70.67±7.8 mgGA/g of extract and 62.81±5.65 mg Quercetin/g of extract, respectively. Addition of celery seed extract (2 and 8%) decreased the moisture content and solubility of the film due to the increase of the film hydrophobicity. Also, by adding the celey seed extract, the elongation at break of the film increased, while the tensile strength and elastic modulus decreased. With the increase in the concentration of the celery seed extract in the film, the DPPH free radical inhibition increases from 14.69 to 73.94%. According to the results of microbial and oxidation tests as well as sensory evaluation, coating a chicken fillet with a chitosan-potato starch film containing 8% celery seed extract would increase its shelf life by up to 15 days.

The aim of this study was to investigate the effect of replacing rice flour with pumpkin powder at different levels (0, 10, 20, and 30% w/w) on the physicochemical and sensory properties of gluten-free rice cake. Wheat cake was prepared by the same method as rice flour with different proportions (0, 10, 20 and 30% w/w) of pumpkin powder as control samples. A factorial experiment with a completely randomized design with three replicates was used for data analysis. The use of pumpkin powder in rice and wheat cake recipes significantly improved the technological properties and sensory attributes of the samples (p < 0.05). With increasing replacement of rice and wheat flour with pumpkin powder (p < 0.05), the viscosity of the rice cake and wheat cake batter increased from 682.66 cp (control sample) to 3518.44 cp (30% pumpkin powder) and from 699.50 cp (control sample) to 4036.92 cp (30% pumpkin powder), respectively (p < 0.05). As the replacement level of rice and wheat flour with pumpkin powder increased, the volume, porosity and lightness of the samples were decreased and the hardness, fiber, and ash were increased (p<0.05). The rice and wheat cakes containing the 20% of pumpkin powder received the highest sensory scores (color, taste, odor, texture, and overall), as compared to control (p<0.05). Addition of pumpkin powder in gluten free rice cake formulation compared with wheat cake formulation improved the lightness and decreased the redness and yellowness of the samples that was acceptable to customers. These achievements will pave the way for using the combination technologies involving the mixing the pumpkin powder and rice flour for improving physicochemical and sensory characteristics of gluten free cakes.

This study aimed to investigate the effect of aloe vera gel coating (Aloe barbadensis Miller) with different concentration on quality and shelf life of fresh fish fillets Asian sea bass (Lates calcarifer) during refrigerated storage (4º) was performed. The desired concentration of 40%, 70%, 100% and a treatment of uncoated as controls. Chemical and microbial tests including TVB-N, TBA, PH , TVC and sensory analysis (color, odor, tissue and general) for treatments on days 1, 6, 11,16 was conducted. The treatments coated with the gel TVB-N and TBA from the sixth day showed a significant difference with the control treatment(p<0/05) And on the sixteenth day of treatment was seen in 40% best results. PH value also increased over time and was higher in the control of other treatments on the final day minimum value PH of the treatment was 70% sample. TVC value is significantly (p<0/05)  higher than the sixth day after the treatment was greater than the other and 40% on the final day had the lowest bacteria count. At the end of the control of chemical and biological indicators on the situation was unacceptable and sensory assessment higher than other treatments to control. As a result of this study, covering 40% and 70% Aloe Vera Gel addition to chemical factors and Asian sea bass fillet also had good effects on sensory index. And cover the gel with a concentration of 40% and 70% for the eleventh day is recommended.

Starch is the most abundant carbohydrate in legumes. On the other hand, due to its non-reactive nature and insolubility in cold water, natural leguminous starch has limited use in the food industry. Natural legume starch can be modified by chemical, physical, and enzymatic methods. Modified legume starches have gained importance in the food industry due to their improved functional properties. Ultrasound is one of the physical methods of starch modification examined in this article. Also, ultrasound is increasingly used as a green technology for the physicochemical modification of food systems. This study aims to investigate the effect of ultrasonic treatment (bath-probe) on the functional, rheological, thermal, morphological, and crystal structure characteristics of modified starch samples. The change in the properties of ultrasonically modified starch is mainly due to the depolymerization of amylose and amylopectin chains. After ultrasound treatment, molecular weight, viscosity, and crystallinity decrease; Therefore, it can be concluded that ultrasound is an alternative technology for modifying the properties of leguminous starch.

Dairy sludge is one of the main and inexpensive wastes of the dairy industry, which contains the nutrients necessary for the growth of lactic acid bacteria (LAB) to produce microbial metabolites, and for its efficient use, optimization of fermentation conditions is critical. In order to optimize the production of dry biomass, three independent variables of dairy sludge concentration (5, 12.5 and 20%), pH (6, 7 and 8) and the inoculation rate of Lactobacillus fermentum strain 4-17 (1, 3 and 5%) were used. Before fermentation, the cell growth and morphology of this bacterium were examined in order to determine the function of the growth rate and confirm the presence of bacteria in this medium. The independent variables were optimized using response surface method (RSM) with central composite design (CCD) in order to maximize dry biomass production by this bacterium. The optimization results showed that the maximum amount of dry biomass production related to the optimal treatment included 20% dairy sludge concentration, 1% inoculation rate and pH 8. Also, according to the results, the dairy sludge substrate is suitable for the fermentation of this bacterium. As a result, the effect of dairy sludge bed concentration and pH on dry biomass production by this bacteria was very significant.

Enrichment is one of the ways to increase the nutritional value of foods. In this research, enrichment of yogurt with Saccharomyces cerevisiae yeast was done as a cheap source of fiber, protein, vitamins and minerals to produce a functional food. Physico-chemical and sensory characteristics of enriched treatments were evaluated. Cow's milk was mixed at 3 levels of fat (1.2, 1.8 and 3%) with yeast at 4 levels (0, 0.3, 0.6 and 0.9%) and used in preparing yogurt samples. The results showed that, in general, fat percentage, yeast percentage and duration of storage on pH and acidity changes were significant at the 95% confidence level. With increasing fat percentage, pH increased and acidity decreased. Increasing the percentage of yeast caused a decrease in pH and an increase. Synergy decreased with increasing the percentage of fat or yeast and also with increasing the duration of storage. The stifness of the tissue increased due to the increase of fat and decreased due with the increase of yeast. The highest level of tissue stifness was 0% in the yeast level and the lowest level was 0.9% in the yeast level. The percentage of fat, percentage of yeast and also the interaction of these two variables were significant and effective on the color index a*, b* with 95% confidence. However, only the variable of yeast percentage had a significant effect on the color index L*. Sensory evaluation results showed that only the variable of fat percentage had a significant effect on aroma, mouthfeel, internal texture, spoon acceptability and overall acceptance.

Honey has been in the interest of mankind for a long time due to its favorable nutritional, medicinal and organoleptic properties. The reputation, price and high demand for this complex matrix of nutrients with antioxidant properties have increased the possibility of adulteration. In this study, 12 samples of natural honey were collected from the farms of Mazandaran province, and their physicochemical and antioxidant properties were compared with 12 commercial honey samples purchased from market in Sari. Honey samples were compared in terms of pH, acidity, moisture, and ash content, electrical conductivity, hydroxymethyl furfural, sucrose content, glucose, fructose, fructose to glucose ratio, refractive index, viscosity, content of total phenolic compounds and antioxidant activity. The results showed that in terms of average pH, acidity, total phenol, moisture, electrical conductivity and ash, almost all natural and commercial samples were within the standard range. The sucrose content and hydroxymethylfurfural in none of the commercial samples was within the standard range. Only three natural honey samples had sucrose content less than 5%. Ten samples of natural honey had less than 40 % hydroxymethylfurfural. Although total reducing sugars in natural and commercial honey samples had no statistically significant difference (p<0.05), all of the natural honey samples and three commercial honey samples had fructose to glucose ratio higher than 0.9. Considering the lower quality of commercial honeys, it is suggested that the inspection organizations pay more attention to the production units of this product.