مجله تحقیقات مهندسی صنایع غذایی
سال بیستم شماره 2 (پیاپی 71، پاییز و زمستان 1400)

Dairy products, due to high daily consumption among the people as a carrier of beneficial compounds and probiotics can be the first option for enrichment. In this study, the production of beneficial products was investigated in cocoa milk containing vitamin D3 at four levels (IU 0, IU 300, IU 400, IU 500 and IU 600) with probiotic Lactobacillus acidophilus (108 CFU / ml). The results showed that the use of vitamin D3 even at a concentration of 600 IU had no significant effect (p> 0.05) on the microbial growth of cocoa milk treatments. The results of physicochemical tests showed that the pH decreased and the acidity increased (p≤0.05). However, other physicochemical parameters such as dry matter percentage and fat content of treatments did not show significant changes (p> 0.05). However, the viscosity of probiotic milk cocoa treatments reached 8.46 milliseconds on the tenth day. Sensitivity to oxidation of the treatments did not show a significant change (p> 0.05) due to the high level of saturated fatty acids in milk, however, probiotic treatments had a higher peroxide index on the tenth day. The results of sensory evaluation showed that enrichment of probiotic and non-probiotic milk cocoa treatments with vitamin D3 had no significant effect. According to the results of tests performed on cocoa milk treatments, the production of probiotic milk fortified with vitamin D3 in the amount of 600 IU was introduced as the superior treatment.

Rapeseed contains one of the highest quality oils with balanced components of saturated and unsaturated fatty acids. During the 2018-2019 academic year, the Bayekola Agricultural Research Station in Neka City conducted a randomized complete block design experiment with three replications. Factors included planting arrangement in two levels: one-row and two-row; and weed control in seven levels of application of herbicides: Treflan lontral herbicide 1 liter per hectare before planting and mixed with soil; butisan star 2.5 liters per hectare before planting and before emergence of rapeseed and weeds; lontral herbicide 1 liter per hectare in stages of 2 to 4 leaves of weeds; paraquat herbicide 2 liters per hectare in stages of 4 to 6 weed leaves; weed control and without weed control. The results showed that changing the arrangement of planting and application of guided herbicide in two rows increased canola seed protein percentage by 21.31%, linoleic acid by 24.22%, linoleic acid by 10.08%, oil yield and yield of canola by 78.46% and 78.48%, respectively. Also, palmitic acid decreased by 11.06% when application of this treatment was made. Therefore, by managing canola agronomy and adjusting the row spacing to utilize guided herbicide paraquat, in addition to weed control, canola also increased protein content, unsaturated fatty acids, oil yield, and rapeseed grain.

The present study was carried out with the aim of optimizing the use of apple pomace as an agricultural residue and apple juice factories. To achieve this, pomace apple extract was extracted using the subcritical water method (extraction temperature of 137 C, extraction time of 29.91 minutes, and water to pomace ratio of 31 ml/g), and the product was coated using different walls (maltodextrin with dextrose equivalents of 7 and 20, and pectin) and the freeze-drying method. The design of the wall composition was done using the software of the response surface and one-way network design with augmented axial points in mixture design(14 mixture walls). Evaluation of the physicochemical properties of microcapsules (moisture content, yield of microencapsulation, total phenolic compounds, strength of the antioxidant component) showed that using a mixture of maltodextrin and pectin walls at the central point of the triangular design (33.33 %) improved physicochemical properties more than the walls alone. Optimizing the concentration of different walls for microporous pomace apple extract using numerical optimization and optimization diagram showed that the optimal wall composition contains 33.41% of maltodextrin wall with dextrose equivalent 7, 35.84% of pectin and 30.75% of the maltodextrin wall with dextrose equivalent 20, dextrose. Also, the effects of free extract (with a concentration of 300 mg/l) and microcapsulated extracts with mixing the optimal walls (with concentrations of 3000 and 4500 mg/l) compared with the addition of synthetic preservative of potassium sorbate (100 mg/l) and the control sample (without any additive substance) on the sensory properties (aroma or taste, smell, and overall acceptance), total phenolic and microbial contamination (the total number of mould and yeast) of oily cakes were evaluated. The results showed that the pomace extract was able to control the growth of mould and yeast by maintaining the sensory and phenolic characteristics in the oily cakes, and the lowest growth of yeast and mould after 9 days of storage in environmental conditions was observed in samples containing 4500 mg/l microcapsulated extract that was approximately equivalent to the effect of the chemical preservative potassium sorbate (100 mg/l).

Potato peel is a by-product of starch production and other potato products. It has notable functional properties and has been considered due to its high absorption properties in the food industry. This study was performed to investigate the effect of potato peel powder on biscuit dough rheology and biscuit properties. The flour was substituted by potato peel powder at the levels of 0, 5, 10 and 15 percent (samples P1 to p4) and the effects were investigated. The results showed that by increasing the amount of potato peel powder, the amount of protein, color indices (L* and b*) and the cohesion of the samples decreased significantly and the amount of fiber, a* index and hardness of biscuit samples increased (p≤ 0.05). No significant differences were observed among moisture, fat and adhesion of samples (p≤ 0.05). The results of sensory analysis also showed that the highest score of taste and smell belonged to samples P1 (no potato peel fiber) and P2 (containing 5 percent potato peel fiber). Also, the highest score of color, texture and overall acceptance belonged to the P1 and P2 samples (p≤0.05) and potato skin fiber caused a significant decrease in color and texture scores of other samples. P2 treatment (containing 5 percent potato skin fiber) was introduced as the best treatment. In general, it can be stated that the addition of potato peel powder, up to 5 percent does not create undesirable changes in the sensory properties of the biscuit and can be applied to fortify the product with fiber.

Cake is one of the most popular bakery products and contains a lot of sugar. In recent years, low-calorie foods with a sugar substitute have had a special place due to consumers' interest in eating healthier foods and a reduced calorie intake. In this study, the feasibility of producing cupcakes with the replacement of sucrose with Quercus was investigated. At the same time, characteristics such as specific gravity, volume, bulk density, physical density, porosity, weight loss, crust and crumb color of cake, hardness, and cake sensory evaluation were studied. Results showed that there was a significant difference in the characteristics of specific gravity dough, volume, bulk density, porosity, and firmness of the cakes compared to the control. As the percentage of Quercus replacement increased, the color of the crust and crumbs of the cake became darker. The highest sensory evaluation score belongs to the 25% Quercus sweetener. The results showed that using 25%, 50%, and 75% substitution of Quercus instead of sucrose improved the quality of the cupcake compared to the control, and the cake sample with 25% Quercus with a maximum volume of 68 cm3 and a specific gravity of 1.13 had the highest quality. With the increase in the amounts of Quercus, some of the quality characteristics decreased, but due to the high score in the sensory test and the beneficial effects of Quercus sweetener, it seems that the Quercus sweetener can be used as a substitute for sugar in the cake.

Food safety and shelf life are the most important concerns of the food industry. Using biodegradable materials as a new method in the packaging industry and combining it with technologies such as nanotechnology and the use of natural herbal materials with antimicrobial properties can improve these terms. The present study was carried out to evaluate the antimicrobial properties of gelatin-Nano cellulose films containing different concentrations of Polylophium involucratum essential oil (PIE) (0, 0.3, 0.6, and 0.9% v/v), Ziziphora clinopodioides essential oil (ZME) (0, 0.3, 0.6, and 0.9% v/v), and tragacanth gum (0 and 1% w/v). The antimicrobial activity of films was evaluated by the disk diffusion method. Antimicrobial results of films revealed that pure gelatin or gelatin/tragacanth films or gelatin/tragacanth films containing 0.3%v/v of ZME did not show any inhibitory effects on tested microorganisms. The maximum inhibition zone was observed for gelatin films containing a combination of 0.9% of both essential oils that created a 22.22 mm inhibition zone for listeria monocytogenes. In this study, the inhibition zone was increased with an increasing concentration of EO, but this was not significant for all concentrations of the four tested microorganisms. According to the findings of this study, gelatin-nanocelulose film containing the ZME, PIE, and Tragacanth can be used in food because of its desired antimicrobial properties.

Optimization of extraction conditions of bioactive compounds from red beet (Beta vulgaris) was performed using response surface methodology. For this purpose, three independent variables were temperature (40, 60, and 80 °C), time (20, 40, and 60 min) and pressure (90, 135 and 180 bar) for modeling and then optimization using Box–Behnken design. Optimization of extraction conditions was determined based on maximum extraction efficiency, maximum total phenolic content, maximum betacyanine content, and lowest IC50 index. The results showed that increasing the temperature (from 40 to 80 °C), time (from 20 to 60 min), and pressure (from 90 to 135 bar) increased extraction efficiency significantly (p<0.05). Also, increasing the pressure from 90 to 135 bar, the temperature from 40 to 60 °C and the extraction time from 20 to 60 min significantly increased total phenolic content, antioxidant activity and betacyanine content of the extract (p<0.05). For red beet extract, the optimum conditions for supercritical carbon dioxide extraction were 58.74 °C and 60 minutes of extraction at 133.99 bar.Under these conditions, extraction efficiency was 1.87, phenolic compounds were 35.67, antioxidant activity was 0.12, and betacyanine content was 3.34.

In this study, the effect of sugar beet fiber on the survival of Bifidobacterium bifidum and the physicochemical and sensory properties of fruit yogurt containing kamquat during storage at 4±1°C was investigated using the response surface methodology (RSM). The amount of sugar beet fiber was in the range of zero to 3%, and storage time was 1 to 21 days. The results of statistical analysis of the data showed that with increasing the amount of fiber and the storage time, the number of Bifidobacterium bifidum increased significantly (P<0.05). With increasing the amount of fiber, the moisture, syneresis, and L* and b* indices decreased, and the a* index increased significantly (P<0.05). During the storage time, the L* and a* indices increased and decreased significantly, respectively (P<0.05). The amount of acidity also increased during the storage period (P<0.05). The results of sensory evaluation showed that with increasing the amount of fiber, color and flavor scores decreased significantly, and during storage time, texture scores increased significantly. Finally, the amount of 2.5% sugar beet fiber was determined as optimal conditions for the production of probiotic fruit yogurt containing kumquat during its 21-day storage time.

Today, due to the high consumption of snacks, improving the nutritional properties and improving the quality of these products is very important. On the other hand, the production of these snacks should be considered for patients with gluten intolerance. So, the aim of this study was to investigate rice flour replacement by germinated and non-germinated soybean and millet flour in level of 20% in gluten free doughnut formulation and evaluation physicochemical, textural, visual, sensory properties and shelf life in a completely randomized design with factorial arrangement (P≥0.05). Based on the results, replacing rice flour by germinated and non-germinated soybean and millet in gluten-free doughnut formulation increased the amount of moisture, protein, and fat in the final product, which the effect of soy flour was higher than millet flour. The findings of this study showed that by replacing rice flour by germinated and non-germinated soybean and millet, the special volume and porosity of the product increases, which affects the germinated soy flour more than other additives. The results also showed that the germinated millet flour sample had the lowest firmness in 2 h, 4 and 7 days after production. On the other hand, the results showed the amount of crust L* value decreased and a* value increased. The results also showed by adding germinated and non-germinated soybean and millet, the amount of total phenolic compounds and antioxidant activity of final products were increased, and the effect of germinated millet flour more than other additives. Finally, the sample containing 20% rice flour and 80% germinated millet flour which had desirable quantitative, qualitative, shelf life and sensory properties, was introduced as the best sample.

Bamboo fiber is extracted from a plant called bamboo belonging to the poaceae family and has no caloric role. This study aims at investigating the possibility of producing breakfast chocolate, while replacing oil with this fiber at five levels, zero, 2.5, 4.5, 6.5, 8.5%. The results showed that replacing oil with fiber up to the level of 8.5% did not have a significant effect on pH values and water activity. It was found that moisture and ash increased significantly (p <0.05), as the fiber increased in the breakfast chocolate formulation). Also, the result of calorie analysis showed that by replacing oil with fiber up to the level of 8.5%, the level of caloric content decreased by 13.42%. The five sensory evaluation of breakfast chocolate formulation also indicated a higher acceptance of the sample prepared with 4.5% bamboo fiber. The results of tissue analysis and measurement of visual viscosity showed that the parameters of visual viscosity, stiffness, cohesion, adhesion and consistency index increased significantly (p <0.05) as the fiber percentage in the formula increased. In general, breakfast chocolate made with 4.5% bamboo fiber can be a good substitute for fat in breakfast chocolate and the optimal formula is able to reduce the caloric content by 6.35%.

Consuming ready-to-eat breakfast cereals has become very popular. Considering that children and teenagers are their main consumers, it is necessary to improve their nutritional value. In the food industry, during food production, preparation and consumption, especially in the process of fruits and vegetables, a large scale of byproduct is obtained, which contains a large amount of protein, essential fatty acids, dietary fibers and minerals that are beneficial for health. In this research, a central composite design was used to investigate the effect of formulation variables including cantaloupe seed flour (20-10%), moisture content (20-12%) and screw speed (120-180 rpm) on the responses of expansion ratio, bulk density, hardness. Texture, water absorption index, water solubility index, color, porosity and sensory acceptance were used. The results showed that increasing the level of cantaloupe flour in the corn grits-wheat flour mixture increases the bulk density, hardness and redness index of the product and decreases the expansion ratio, porosity, and water absorption index in the product. The optimal conditions of the extrusion process were determined at 10% cantaloupe seeds, 19.68% feed moisture and screw speed 180 rpm.

In the present study, WPI (Whey Protein Isolate) based films containing 0, 1, 2.5, 5, and 10% essential oil of thyme were prepared and physicochemical properties (thickness, inflation index, water solubility, water vapor penetration, color parameters, total phenol content, and antioxidant activity) and mechanical properties (tensile strength and elongation percentage) of films, as well as antimicrobial activity against penicillium cryzogenum (stored pita bread at ambient temperature for 7 days) and sensory quality of packaged pita bread were evaluated. The results showed that application of thyme essential oil in WPI-based films significantly (p<0.05) increased the thickness, prolongation, and yellowing index (b*) of films. Thyme essential oil decreased significantly (p<0.05) the inflation index, water solubility, steam permeability, L* and a* indexes, and the tensile strength of active films. By increasing levels of thyme essential oil, phenolic compounds increased and IC50 (Inhibitory Concentration) decreased. Antifungal activity was increased due to the concentration of thyme oil in films. Increasing the concentration of thyme essential oil resulted in a significant decrease in the growth of penicillium cryozogenum in pita bread during storage. Based on the results of sensory evaluation, packaged bread with active WPI films containing 10% Thyme essential oil had the highest sensory rating, but bread packed with WPI films had the lowest sensory rating in terms of overall acceptance.