دکتر محمدهادی خوش تقاضا

With the global population increasing, coupled with rising incomes and growing health consciousness, the demand for milk and dairy products is expanding rapidly. Cavitation, has emerged as an effective technique for enhancing milk processing in the dairy industry. This review focuses on exploring different cavitation induction methods used in milk processing and analyzing their impact on the nutritional value of milk.

 Using a scoping review methodology, this study collected data from both authoritative Persian databases, including SID and ISC, and international platforms like Google Scholar, Scopus, PubMed, and Web of Science. The search covered documents published between January 1, 2010,
and January 1, 2024, in accordance with predefined research questions and inclusion criteria.

 The initial search yielded 873 documents, of which 15 met the criteria for detailed analysis. The effects of various cavitation induction methods on the nutritional content of milk were categorized into five key areas: fats, proteins, vitamins, minerals, and organoleptic characteristics.

 Cavitation significantly reduces the time and energy needed for pasteurization and homogenization by minimizing thermal processing, thereby improving milk quality. Among the two primary cavitation methods, hydrodynamic cavitation is particularly effective at preserving milk’s nutritional value and enhancing its flavor profile. As a result, it offers a promising alternative or complementary approach to conventional milk processing techniques.

More than half of foodborne illnesses are attributed to pathogenic bacteria, posing considerable health and economic dangers. Salmonella enterica serovar Enteritidis (SESE) is a prevalent bacterial pathogen responsible for a higher number of hospitalizations and fatalities compared to other bacteria. Non-thermal plasma, an innovative decontamination technique, exhibits the potential to serve as an intervention strategy for food safety. The study aimed to explore the possibility of deactivating SESE through a brief industrial treatment utilizing non-thermal atmospheric cold plasma of dielectric barrier discharge (DBD) devices. To assess the reduction of SESE, air was used as the process gas under different experimental circumstances, with Petridishes containing an initial concentration of 107 CFU/mL. Emission spectroscopy was employed to monitor the key factors of plasma deactivation, namely ultraviolet radiation and reactive species. The application of the DBD cold plasma device resulted in a decrease in SESE concentration by over 7 log CFU/mL following a 60-second treatment. Moreover, scanning electron microscopy revealed that atmospheric cold plasma treatment caused significant physical damage to the cells.

Iran is one of the world's largest and most important raisin-producing countries. Considering the amount and value of raisin exports in Iran, mechanizing this product's collection and maintaining its mechanical quality is one of the most necessary tasks in this field. Therefore, the main purpose of this study is to design and construct a collection head in a Rover for collecting raisin products from the ground and then evaluate the mechanical damage of raisin crops during collection from the ground by the collecting head. After performing the software design, the necessary calculations were performed to select different device parts. The rover was evaluated on raisins spread on the ground at three forward speeds of the rover (1, 2 and 3 km/h) and three heights of the head (2, 5 and 10 mm) from the ground surface. The constructed head with a length of 80 cm was mounted on a rover with dimensions of approximately 70 × 50 cm. The working capacity of this machine at the rotational speed of 25 rpm of the collecting brush is equal to 3.3 kg/min, and it is able to fill the 80 kg container every 15 minutes. The evaluation results showed that the effect of forward speed and head height on mechanical damage was significant (p <0.01), but their interaction was not significant. Also, the lowest mechanical damage (11%) was related to the height of 2 mm from the ground. Mechanical damage of the product was reduced by 8% at the forward speed of 1 km/h compared to the other two speeds.

Orange is one of the most important citrus species in the economy and industry. This study aimed to dry the oranges with a combined pretreatment of osmotic solution and ultrasound waves to reduce the drying time and improve the quality of the dried product. In this study, a hot air dryer was used to investigate and optimize drying time, water reabsorption capacity of dried samples and shrinkage index of dried samples of orange slices. The samples were pretreated by immersing them in an osmotic solution with brix at three levels of 15, 30 and 45 degrees and applying ultrasonic waves to the samples at three-time levels of 10, 20 and 30 min in the ultrasonic bath. The pretreated samples were dried at three temperature levels of 70, 80 and 90℃ and three hot air velocities of 1, 1.5 and 2 m/s. The results showed that by increasing the concentration of an osmotic solution from 15 to 45 and increasing the ultrasonic time from 10 min to 30 min, the total drying time and the shrinkage index of the product decreased. The water reabsorption of the dried samples was dependent on the variables of ultrasonic time and osmotic solution concentration (P<0.01). The best state of water reabsorption, which was 8.9, occurred at 15° Brix and 30 min of ultrasound. The optimization results showed that the optimal point with the highest desirability index (0.808) occurred at 45° Brix of the osmotic solution, 30 min of ultrasound, 70°C and 1.07 m/s of hot air dryer.

Microbial contamination of spices and medicinal plants at various stages of the production leads to low quality and shorter shelf life. As a result, sterilization is required to decrease the microbial load. The purpose of the current study was qualitative comparison of the two methods induction heating technology (115, 135 and 155 °C for 45, 60 and 75 s) with gamma irradiation (5 and 10 kGy) for sterilization of cumin seeds. For this purpose, microbial load (total microbial count, mold and yeast and coliform), total color differences and essential oil content were studied as quality properties of cumin seeds. After examining the influence of various induction heating system treatments on the specified parameters, process optimization was carried out by using the response surface methodology. Optimal decontamination conditions were obtained with a combined treatment of 151 °C -46 s. In these conditions, total microbial count, mold and yeast, coliform, total color differences and the amount of essential oil were 3.06 CFU/g, 3.1 CFU/g, 2.28 CFU/g, 4.15 and 2.57%, respectively. The optimal points of the induction heating method were validated and compared with the gamma irradiation method. The results showed that gamma irradiation caused in the greatest decrease of microbial load (1.52 CFU/g) (10 kGy). The least amount total color differences were found at 5 kGy treatment with a value of 2.76. No significant effect on total color differences was identified between gamma irradiation (10 kGy) and induction heating system. The highest and lowest levels of essential oil were found in the induction heating treatment (151 °C -46 s) and gamma irradiation (5 kGy), with the values of 2.45 and 1.7 %, respectively. According to the results of scanning electron microscope, induction heating led to a change in the surface structure, pores and cracks in the seed surface compared to gamma irradiation.

In the recent years, agricultural products packaging was faced with some challenges. One of these challenges is measuring the oxygen and carbon dioxide amount during the respiration of stored products. Due to the high cost of the sensors and measuring devices of oxygen and carbon dioxide, the researchers have been looking for alternative methods for those measuring. The major aims of this study is to find a mathematical measurement method based on temperature, humidity ratio, and absolute and differential pressure during the respiration of lettuce storage. The present study was conducted at three temperature levels (5, 15, and 25 °C) and three storage time levels (24, 48 and 72 h). Based on the results of the mathematical model, the accuracy of prediction at the storage temperature of 5, 15, and 25°C for oxygen measurement were 96%, 98% and 97% and for carbon dioxide measurement were 95%, 99% and 98%, respectively. The statistical analysis of the variation parameters of carbon dioxide, humidity ratio and absolute and differential pressure with the variation of temperature and storage time of lettuce was significant at 1% levels.

A novel approach for bio-lubricant production from rapeseed oil-based biodiesel using ultrasound irradiation: Multi-objective optimization Moringa oil is used as a useful oil in the food, medicinal, cosmetic and health industries. Also past research has shown that microwaves can increase the extraction efficiency of oil by disintegrating the cellular structure of oil seed. Therefore, in this research, for increasing oil extraction efficiency, microwave pretreatment was used before oil extraction from Moringa seeds by spiral press. In this study, the optimization of oil mechanical extraction from Moringa seeds was done using the Response Surface Methodology. In this study, extraction experiments were done with microwave pretreatment at different level of times (2, 3 and 4 min) and powers (200, 400 and 600 W). The results showed that the extraction efficiency increases and then decreases by increasing microwave time and microwave power. The optimum extraction efficiency was 56.55% during the microwave action time of 3.02 min and the microwave power intensity of 380.92 W. Due to the high values of correlation coefficients (R2 = 0.97) the predicted model for oil extraction efficiency can be evaluated properly.

This study was conducted to evaluate the influence of gamma irradiation doses and packaging materials on the shelf life of edible button mushroom )Agaricus bisporus). To do so, the fresh mushrooms were packed in two different packages: (polyethylene and nanocomposite) and immediately irradiated (0, 1, 2 and 3 kGy) then stored (2–3°C). The effect of these parameters on qualitative characteristics of mushrooms (weight loss, cap diameter, pH, total soluble solids, firmness, and whiteness) during storage (1, 5, 10, 15 and 20 days after irradiation) was evaluated. Our findings showed that the mutual interaction of irradiation dose and packaging material, also irradiation dose and storage time were significant (p < 0.01) in all measured properties except firmness. It can be concluded that using proper doses of irradiation (1-2 kGy) and appropriate packaging material (nanocomposite) could significantly increase the shelf life of edible button mushrooms for 20 days.

In this study, the effect of ultrasound on the germination and vigor index of Iranian black cumin (Bunium persicum Boiss.), was studied. Response surface methodologhy and central composite design were used ti analyze the data and optimize the experiment. A factorial experiment based on completely randomized design was conducted. Experimental factors included time of ultrasound treatment (5, 7 and 9 minutes), ultrasonic power (130, 180 and 230 watts) and sonication temperatures (10, 20 and 30 °C) as well as control and germination percentage and seed vigor index were measured. The highest germination percentage and seed vigor index were determined by Response Surface Methodology (RSM). The results indicated significant effect of time and ultrasound power on studied traits, but temperature had no significant effect on them. The highest germination percentage (61%) and seed vigor index (800) were observed at 180 W and 7 min duration time and 20 °C. The lowest germination percentage (24.5%) and seed vigor index (462) were observed in 230 W ultrasound power, 9 min duration time and 20 °C. Also, the optimization results showed that the best points for power, time and temperature for achieving the highest values of germination percentage and seed vigor index were 175.47 W, 6.37 min and 19.36 °C, respectively and the output values (germination and seed vigor index) were obtained the this points 63.02% and 808.39 respectively. Finally it seems that the increasing or decreasing time and power of ultrasonication in a certain range decreases the seed germination percentage and vigor index.

In the processing of vegetables as well as preparation for fresh consumption, the leaf part of the vegetable is separated from the stem manually and non-mechanically. This research was carried out in order to design and development an automatic system for precise cutting of vegetable stems harvested from the field. Machine vision was used to determine the appropriate cutting position. In this way, after placing the product on the conveyor, it is automatically photographed and after identifying the cutting location, a cutting mechanism separates the leaf part of the plant from its stem. The designed cutting system performed the cutting of the samples with an accuracy of about 3 mm. It takes about 4 seconds to identify the cutting location and perform cutting, so the maximum capacity of the machine is 15 cuts per minute. The output of the machine had acceptable quality in cases where the incoming vegetables were evenly and freshly harvested.

One of the most important and sensitive steps after walnut harvesting is the separation of the kernel from its shell. Walnut rupture force is an appropriate criterion for design with high performance and better quality, which can be used as the basis for designing and adjusting the various parts of machines that are in contact with walnut. The lower rupture force caused the less energy requirement to separate the walnut kernel from the shell. The use of ultrasound in ambient fluids is well known to cause turbulence and biological cell rupture. These effects arise principally from the phenomenon known as cavitation which can scour surfaces and damage cellular material. Therefore the object of this study is to find the effect of ultrasound factors on the amount of walnut rupture force and quality of kernel extraction.

Walnut paper variety was selected from a Qazvin province orchard for this study. To determine the initial moisture content of the nuts, the samples were dried in an oven at 105°C for 24 h. Initial moisture content was found 5.5 (%w.b). The ultrasounds bath system (D-78224 Singen/htw, Elma, Germany) was used with a nominal frequency of 50 kHz and power of 1000 W. In this research, based on the pretest results and previous studies (Cao et al., 2010; Entezari et al., 2004) walnut samples were treated with three ultrasound time duration (5, 10 and 15 min) and three ultrasound bath temperature (20, 35, and 50ºC). Moisture content of the walnuts after ultrasound treatment was 8.8 (%w.b). After the walnut samples were treated by ultrasonic factors, a material testing machine (H50 K-S, Hounsfield, England) was used to determine the rupture force of the walnuts. The walnut was placed between two plates, and loaded at three loading speeds (0.5, 1.5, and 2.5 mm s-1) and pressed until the walnut ruptured. Rupture force was applied along with X and Y axes. The X-axis was in the longitudinal axis through the hilum to the tip (length) and the Y-axis was in the latitudinal axis (width) at right angles to the X-axis. Kernel extraction quality was classified into grades according to size and number of broken pieces of the kernel. Central composite design (CCD) of resound surface method was used to optimize the effect of ultrasonic factors on walnut kernel extraction.

The results indicated that the loading speed, ultrasound time duration, loading direction, and moisture content had a highly significant effect (P<0.01) and ultrasound bath temperature (P<0.05) on the rupture force and kernel extracting quality. Regarding the sum of squares of ANOVA results, the ultrasound time duration factor had the most effect on the rupture force and the loading direction factor had the most effect on kernel extraction quality. By increasing bath temperature and ultrasound time duration, walnut rupture force was decreased. The minimum walnut rupture force was obtained in 25 min ultrasound time duration, 50ºC bath temperature, 1.5 mm s-1 loading speed, and width loading direction for wet walnut. By increasing bath temperature, walnut kernel losses were increased. The best kernel extraction quality was obtained in 2.5 mm s-1 loading speed, 25 min ultrasound duration, 20ºC bath temperature, and longitudinal loading direction. The proposed optimal point was obtained at 64.4 N rupture force, and two half of the kernel at 1.3 mm s-1 loading speed,  25 min ultrasound duration, 50ºC bath temperature, and longitudinal loading direction for wet walnut.

The walnut ultrasound treated samples had minimum rupture force and the best quality kernel extraction. It was observed that by increasing the loading speed and ultrasound time duration, the percentage of whole kernels and the quality degree of broken kernels increased.

Drying of medicinal and aromatic plants (MAPs) is a widely spread method offering physico-chemical stabilization by taking away part of the moisture content, producing different products with different qualitative properties and economical value. The main purpose of MAPs drying is to extend product shelf life, minimize packaging requirements and reduce shipping weights. Drying is used to stop the growth of microorganisms and preserve the quality of MAPs. There are different drying methods and their suitability can be determined by energy efficiency, drying time, preservation of active substances and other quality properties of the product, depending on market demand. Therefore, determining a suitable drying method to achieve higher active substances in medicinal plants is very important. Advantages of infrared drying include high efficiency of conversion of electrical energy into heat, a suitable alternative source for thermal energy, and uniform heating of the product surface. The aim of this study was to investigate the effect of infrared drying on drying time and the qualitative characteristics of sumac fruit (total color changes, total phenolic content, organic acids, and vitamin C).

Sumac fruits (from the forests of Sardasht city in West Azerbaijan Province, Iran) were used after complete separation from clusters and additional parts for drying and performing the desired treatments. In this research, an infrared dryer was used to dry the sumac sample which was made by the Department of Biosystems Engineering of Tarbiat Modares University. For this study, a factorial experiment was performed based on a completely randomized design. In this experiments, three levels of radiation intensity (0.2, 0.3 and 0.5 watts per square centimeter) and three levels of air velocity (0.5, 1 and 1.5 meters per second) were used. The sample tray inside the dryer was connected by a rod to a digital scale at the bottom of the dryer. The scale had a computer connection port that could measure and record the weight of the fruits continuously during drying. To determine the initial moisture content, 3 samples (50 g) were placed in an oven at 105 °C and after three hours, the samples were taken out of the oven and weighed, and finally the moisture content of the product was calculated on wet basis. The initial moisture content of sumac fruits was approximately 17%. Drying was continued until the product reached a moisture content of 7%. Drying time and quality characteristics of sumac fruit (color changes, total phenolic content, organic acids, and vitamin C) were measured. Colorimeter (Hunterlab, Color Flex model, USA) was used to check the color changes of sumac fruits during drying and the total color changes ( ) compared to the fresh sample were calculated. To measure the total phenolic content, Folin-Ciocalteu phenol reagent was used by a spectrophotometer (Samsung, Smart Spec Flus model, South Korea). Titration method was used to measure vitamin C and organic acids. Finally, based on all the mentioned parameters, the optimization was performed by Design Expert software (version 10) and the best score was obtained based on the utility index.

The results showed that the intensity of infrared radiation and air velocity had a significant effect on the studied characteristics except total phenolic content. The minimum and maximum drying times were obtained at the highest and lowest infrared intensities and air velocities, respectively. Increasing the infrared intensity and subsequently increasing the temperature had a negative effect on the total color changes, organic acids and vitamin C, so that the least total color changes and the highest amount of organic acids and vitamin C were obtained by reducing the intensity of infrared radiation. The lowest total color change and the highest amount of organic acids were obtained in the treatment of 0.2 W cm-2 × 1.5 m s-1 and the highest amount of vitamin C in 0.2 W cm-2 × 1 m s-1 and 0.3 W cm-2 × 0.5 m s-1 treatments, respectively. The values obtained from the optimization parameters for the studied indicators (drying time, total color changes, organic acids, and vitamin C) showed that the best point for drying of sumac fruit was the infrared radiation intensity of 0.3 W cm-2 and air velocity of 0.5 m s-1. In this treatment, the highest utility index obtained by software was 0.71.

Infrared drying reduced the drying time of sumac fruit compared to traditional drying methods (shade and sun drying). In addition to reducing the drying time, infrared drying was a suitable method for preserving the phytochemical properties and color changes of sumac fruits.

In this study, the effect of microwave drying method (at five power levels: 200, 400, 600, 800 and 1000 watts) on drying time, color change, amount of organic acids and vitamin C of sumac fruit (Rhus coriaria L.) was investigated. The experiment was conducted in a completely randomized design with three replications and the response surface methodology (RSM) was used to find the optimum points for the minimum drying time and color changes or the maximum organic acids and vitamin C during drying. The results showed that microwave drying had significant effect on the color, the amount of organic acids and vitamin C at 5% probability level but it had significant effect on drying time at 1% probability level. Among the different microwave powers, the highest and lowest organic acids were obtained at 1000 and 600 watts with values of 1.46 and 1.11 mg/100 g, respectively, and the highest and lowest vitamin C was obtained at 600 and 1000 watts with values of 0.40 and 0.26 mg/100g, respectively. The best situation for microwave drying (with the lowest drying time and color variations and the maximum phytochemicals) was obtained at 815 watts. Finally, the lowest color changes and the highest amount of organic acids and vitamin C were observed in the shade drying method.

The tendency toward research on the production and application of renewable energy, such as biodiesel, to reduce greenhouse gases and emissions of fossil fuels, is one of the most important issues in the world policies which has been discussed. Dielectric properties (ε’, dielectric constant and ε", dielectric loss factor) of materials play a major role in the microwave design and process of biodiesel production. The purpose of this research is to investigate and evaluate the biodiesel's dielectric properties in a pilot-scale using microwave technology and the relationship between its various effective parameters. In this study, the effects of reaction time (1, 3 and 9 minutes), catalyst concentration (1, 1.5 and 2% of oil weight) and temperature changes (30, 45 and 60°C) were studied. The probe reflection system was used at a frequency of 2450 MHz to measure the dielectric properties. The results showed that, with increasing reaction time and decreasing temperature, the dielectric constant values increased, and by decreasing catalyst concentration, temperature and reaction time, the dielectric loss factor decreased.

The usage of biodiesel quality monitoring system (online and batch) is always the basic requirement of its production which requires to research in this area. The purpose of this study is to predict and optimize the palm biodiesel characteristics using its permittivity properties. The parameters of biodiesel permittivity properties (ε’, dielectric constant and ε″, loss factor) at microwave frequencies of (434, 915 and 2450 MHz) were used as input variables. The palm biodiesel characteristics as fatty acid methyl ester (FAME) content and flash point (FP) at three different level of reaction time (3, 9 and 27 min) and catalyst concentration (1, 1.5 and 2 % w/woil) were selected as output parameters for the models. The response surface methodology was developed for prediction and optimization of FAME content and flash point. The optimum condition was obtained using RSM by FAME content of 95.87% and flash point of 162.7 °C with desirability of 0.999.

The final quality of drying product should be considered as one of the most important indicators in the drying process.In this research, the effects of gamma irradiation doses (0, 1.2, 2.4 and 3.6 kGy), drying temperature (50, 60 and 70°C) and slice thickness of mushrooms (3 and 5 mm) on the surface shrinkage and rehydration ratiowere studied.Thin-layer dryer based on machine vision was used for the experiment.The results showed that the simple and intraction effects of the factorson the surface shrinkage and rehydration ratio weresignificant(P<0.01)in most cases.By increasing irradiation dose, shrinkage slightly increased, and rehydration ratio in dried samples were increased. Also,the maximum rehydration ratiowas 3.43g/gin dose of 3.6 kGy anddryingtemperature of 60°C in the thickness of 3 mm.Finally, shrinkage increased by increasing drying temperature and decreasing slicethickness of mushroom.So that the minimum and maximum values of surface shrinkagewere 0.461 and 0.667, respectively.

Drying is used as a suitable method for increasing shelf life of agricultural different products. In this research, kinetics modeling of parboiled rice drying in a combined infrared-hot air dryer was investigated. The effect of hot air temperature at 3 levels of 40, 50 and 60oC, infrared radiation intensity at 2 levels of 0.32 and 0.49 w/cm2 and air velocity 1 m/s were evaluated during drying of parboiled rice on head rice yield in a completely randomized design. The results showed that the effect of hot air temperature and infrared radiation intensity on the drying time of parboiled rice was significant (P

It is important to increase storage quality of orange by using of natural coatings. In this research, quality of Thomson oranges coated with chitosan-clay nano composite edible coating and fogger - wax (fog production from Ortho Phenil Phenol by electro fogger with nano dimension) was compared with the sample without coating during storage. Orange quality properties were evaluated during storage for 3 months in a cold storage at 6oC temperature and 85-90% relative humidity. Results showed that fruits coated with chitosan-clay had highest pH, chroma, peel moisture and firmness compared to the other samples. Therefore, this nano coating increased fruit resistance to fungal diseases, retained peel fruit color and inner texture strength during storage. Amount of total soluble solid and acid total of fruit juice for fogger - wax coating decreased and increased during storage, which this trend could indicate fermentation phenomenon in the fruit. So using of chitosan-clay nano composite edible coating can be offered for prevention of decrease fruit quality during storage.

In this study, pomegranate arils were dried by infrared dryer to find a suitable mathematical model, effective moisture diffusion coefficient and activation energy. The experiments were performed at four air velocity levels (0.3, 0.5, 0.7 and 1 ms-1) and three infrared radiation levels (22, 31 and 49 W cm-2). Experimental data with semi-theoretical and empirical models were evaluated to find the best model. Among the models, Midili's Model was selected based on R2, χ2 and RMSE criteria. Effective diffusion coefficient of pomegranate arils was in the range of 0. 4×10-9 to 3.21×10-9 m2 s-1. Activation energy was calculated by using Arheneus exponential model. The values of activation energy were determined in first method between 0.43 to 1.17 W g-1 cm-1 and second method between 1.1 to 0.72 W g-1 cm-1.

The common method used for juice pasteurization is the thermal method since thermal methods contribute highly to inactivating microbes. However, applying high temperatures would lead to inefficient effects on nutrition and food value. Such effects may include vitamin loss, nutritional flavor loss, non-enzyme browning, and protein reshaping (Kuldiloke, 2002). In order to decrease the adverse effects of the thermal pasteurization method, other methods capable of inactivation of microorganisms can be applied. In doing so, non-thermal methods including pasteurization using high hydrostatic pressure processing (HPP), electrical fields, and ultrasound waves are of interest (Chen and Tseng, 1996). The reason for diminishing microbial count in the presence of ultrasonic waves could be due to the burst of very tiny bubbles developed by ultrasounds which expand quickly and burst in a short time. Due to this burst, special temperature and pressure conditions are developed which could initiate or intensify several physical and/or chemical reactions. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. In order to supply uniform ultrasonic waves, a 1000 W electric generator (Model MPI, Switzerland) working at 20±1 kHz frequency was used. The aim of this study is to evaluate the non-thermal ultrasonic method and its effective factors on the E.coli bacteria of sour cherry. For this purpose, a certain amount of sour cherry fruit was purchased from local markets. First, the fruits were washed, cleaned and cored. The prepared fruits were then dewatered using an electric juicer. In order to separate pulp suspensions and tissue components, the extracted juice was poured into a centrifuge with the speed of 6000 rpm for 20 min. For complete separation of the remaining suspended particles, the transparent portion of the extract was passed through a Whatman filter paper using a vacuum pump (Mehmandoost et al., 2011). Afterwards, the samples were poured into a reactor with diameter and height of 80 and 50 mm, respectively. It is necessary to mention that the dimensions of the reactor were optimized during pretests. Probe design: One of the most common types of horns used for ultrasonic machining technologies is step type horn (Naď, 2010). For obtaining the governing equations on deformation along the step type horn in steady state conditions, Eq. (1) was used. In the solution of the mentioned differential equation, the answers are divided into two subsets and each of the answers is obtained considering the boundary conditions (Hosseinzadeh et al., 2013): (1) c^2.[(∂S/∂x)/(S(x)).(∂u(x,t))/∂x+(∂^2 u(x,t))/〖∂x〗^2]=(∂^2 u(x,t))/〖∂t〗^2 From Eq. (1), it can be concluded that: (2) u(x,t)=(A cos⁡〖ωx/c〗+B sin⁡〖ωx/c)(C cos⁡〖ωt+D sin⁡ωt 〗 〗)The boundary conditions for Eq. (2) are written as follows: (3) {■(a) (∂u(x))/∂x=0,x=0@b) (∂u(x))/∂x=0,x=l@c) u(0)=u_in)} One of the most important parts in probe design is preventing stress concentration in locations in which the area changes. To avoid this problem, the displacement in this section must be equal to zero (Hosseinzadeh et al., 2013). For obtaining the probe length, the displacement equation and the l1 parameter are used:σ=-E.u_in.ω/c.sin⁡〖(ω.x)/c〗 (4) In order to determine the maximum axial stress in step type probe, Eq. (3) and (4) are derived and set equal to zero. Therefore, the maximum stress will be equal to:σ_max=π.E.u_in/l (5) Optimization and Modeling using Response Surface Response surface methodology (RSM) has an important application in the design, development and formulation of new products, as well as in the improvement of existing product designs. It defines the effect of the independent variables, alone or in combination, on processes. In addition, to analyzing the effects of the independent variables, this experimental methodology generates a mathematical model which describes the chemical or biochemical processes (Anjum et al., 1997, Halim et al., 2009). In order to obtain the optimum value, Eq. (1) will be used: (6) Y_i=β_0+∑▒〖β_i X_i+∑▒〖β_ij X_i X_j+〗〗 ∑▒〖β_ij X_i^2 〗+εwhere, β0, βj, βij, βjj are regression coefficients for intercept, linear, interaction and quadratic coefficients, respectively, while Xi and Xj are coded independent variables and ε is the error. For this purpose, four factors of ultrasonic power (200 to 600 W), wave exposure time (5 to 15 min), probe diameter (20 to 40 mm), and probe penetration depth in sour cherry juice container (0 to 40 mm) were selected. First, the probes with the desired diameters were designed using the related formulas by using CAD-CAM. Surface Method (RSM) indicated that the quadratic model with 0.96 coefficient of friction, standard error of 1545.3, and coefficient of variation of 14% is the best model for estimating the number of E.coli bacteria among the different studied treatments. The results showed that with increasing probe diameter and probe depth, the destructive effects of ultrasonic wave increase. It was also revealed that as the probe diameter and penetration depth increase, the destructive effect of ultrasonic wave is initially increased and then follows by a decreasing trend. With the increasing power of ultrasonic, ultrasonic intensity increases and leads to reducing number of E.coli in sour cherry juice. The increase in time of treatment with ultrasonic causes a decrease in the number of E.coli in sour cherry juice. This is due to the fact that the increase of ultrasonic exposure time leads to the increase of sonic stream in reactor and results in higher contributions of ultrasonic waves to E.coli. Finally, the examined variables were optimized by RSM and the values of ultrasonic power, waves exposing time, probe diameter, and probe penetration depth were obtained as 600 W, 15 min, 35.31 mm, 20.83 mm, respectively. Considering the mentioned values, the amount of E.coli bacteria reduction was estimated to be 1.97 logarithmic period. 1. Increasing probe diameter and probe depth increasesthe destructive effect of ultrasonic wave. 2. The examined variables were optimized by RSM and the values of ultrasonic power, waves exposure time, probe diameter, and probe penetration depth were obtained as 600W, 15 min, 35.31 mm, 20.83 mm, respectively. Considering the optimum values, the amount of E.coli bacteria reduction was estimated to be 1.97 logarithmic period. 3. With the increasing power of ultrasonic waves, ultrasonic intensity increases and leads to a reduction of the number of E.coli in sour cherry juice. 4. The increase in time of treatment with ultrasonic causesa decrease in the number of E.coli in sour cherry juice.