فصلنامه پژوهش های صنایع غذایی
سال سی و سوم شماره 3 (پاییز 1402)

Anthocyanins are the most important flavonoid pigments which have health benefits for concumers due to their high antioxidant activity. These compounds are non-toxic and water-soluble, and with attractive and bright colors of red, blue, and purple, are good alternatives to harmful chemical dyes. Blackberry fruit is one of the rich sources of anthocyanins in nature. Blackberry anthocyanins have been considered as healthy and effective food colors in the food industry due to the presence of dark purple color along with abundant nutrients. However, unfavorable physical and chemical conditions may cause spoilage and color changes in the natural pigments of this fruit. Blackberry fruit is a good source of vitamins A, B, C, E and K as well as iron, potassium, manganese, magnesium, niacin, riboflavin, folic acid, glucose and tannin. The presence of many nutrients along with high antioxidant activity has made this fruit to be considered as a suitable source for meeting the daily need for various micronutrients. Based on this, with the correct processing of blackberry extract, its anthocyanins can be used not only as a natural color but also as a harmless sweetener and a substance with excellent micronutrient properties in various food industries.

the purpose of this study is a comprehensive study on the degradation factors of blackberry anthocyanins to find appropriate protection methods, and their subsequent use in the food industry.

In this research, various methods of extracting color from blackberry fruit were investigated, including the use of different solvents and different temperatures, and finally it was determined to use acidic ethanol and acidic methanol solvents and then evaporate the solvent in a vacuum and low temperature. It has the best efficiency in extracting color from blackberry fruit. These results show that the more the structure of the solvent is similar to the structure of the extracted pigment, the higher the percentage of extraction. Considering less toxicity, 0.1% acidic ethanol solution (ethanol + hydrochloric acid) was considered as the extraction solvent. In summary, liquid-solid phase extraction method, extractive phase separation and subsequent evaporation of the extraction solvent in vacuum and low temperatures of 30 to 40°C were used to extract anthocyanin. After extracting and enriching the anthocyanins of blackberry fruit and determining its properties, the effect of various physical and chemical parameters such as temperature, light, presence of enzymes, different pHs, presence of oxygen, and the addition of authorized food additives on the quality and stability of this pigment was investigated and ways of optimization them were evaluated.

By performing various tests, it was found that the use of acidic ethanol solution provides the highest color extraction efficiency with the lowest amount of degradation. Examining the physical and chemical properties of the extracted anthocyanin showed the presence of 15% dry matter, 85% moisture and 14.5% soluble solids. Also, the extracted color has acidic properties. Based on the obtained HPLC chromatogram analysis, five anthocyanins were identified in the blackberry extract, and cyanidin 3-glycoside was the dominant type of blackberry color anthocyanin. The amount of absorption and total anthocyanin in the enriched extract of blackberry fruit was found to be 0.32 and 24.3 mg/liter, respectively, which is a significant amount and indicates the appropriate enrichment of the extracted anthocyanin. It was also found that by using the wind tunnel it is possible to dry and powder the paint without reducing the quality. Investigating the stability of enriched anthocyanin pigments showed that light and temperature are two important factors in the stability of blackberry anthocyanins, and by removing light and reducing temperature, the stability of anthocyanins can be increased to a great extent. . The natural enzymes present in the blackberry fruit destroy the chemical structure of cyanidins, and by deactivating them, the color of the product is well preserved. Also, the enzyme helps to prevent the growth of molds. The highest concentration of anthocyanin and the highest color intensity were obtained in the range of pH = 3-4, which corresponds to the natural pH of the extracted solution (pH = 3.2) and the further away from the natural pH of the product, the concentration anthocyanin decreases. However, anthocyanin is more stable under acidic conditions and has a higher concentration. Oxygen also destroys anthocyanins. However, the use of nitrogen gas not only prevents the destruction of pigment by oxygen, but also prevents the growth of mold. By adding food additives such as sorbitol, glucose, carbon dioxide and citric acid, the color stability of the extracts increases and citric acid prevents the growth of molds. Finally, according to the quality and intensity of the enriched anthocyanin color obtained in this research, it is possible to use it in the food industry.

The results demonstrated that cyanidin-3-glycoside is the main anthocyanin in blackberry fruit. Light, temperature, changing pH, and the presence of oxygen reduce the stability of anthocyanins by 56.5 to 88.2%. On the other hand, the addition of authorized food additives such as carbon dioxide, citric acid, glucose, sorbitol, and nitrogen gas helped stabilize the pigments. Thus, the samples retained their color up to 98.8, and 93.6%. in darkness, and indirect light, respectively.Keywords: Anthocyanin, Blackberry, Stability factors, Natural pigments

Unit operation of heat processing is common in food process industries. Most unit operations such as canning, pasteurization, and sterilization are based on the heat process. In the traditional food heating process, the food is filled in a package and then the heat process starts, but in some new technologies such as the aseptic process, the food heat processing is before the packaging and after heating, food will be packaged in a sterilized condition. The aseptic process needs a high temperature for sterility. But in comparison with traditional heating sterilization can destroy the microorganisms at high rates and also can more deserve the texture, flavor, color, and nutritional elements of food. The foods which are processed under aseptic conditions show higher shelf-life, and nutritional characteristics and their packaging in different types and sizes is possible. These factors make the aseptic process more attractive for use in food sterilization. Today the numerical simulation is used for investigating the temperature and lethality to insurance how the food fluids reach the determined temperature during the aseptic heating process. Since the viscosity and velocity of the fluid and the design of an aseptic heat exchanger are effective on the temperature profile of fluids, in this manuscript the numerical simulation was used for studying the lethality and temperature profile inside a broken heating non-Newtonian fluid.

In this study, a 3.5% starch dispersion was used for simulation. Since the starch dispersion is a broken heating fluid, three temperature limitations were assumed for viscosity changes during sterilization. The first limit was 78-89℃, which relates to the starch pre-gelatinization limit and shows the starch dispersion viscosity is increasing to make a starch paste, and the second at 89.5-92.5℃ which relates to starch gelatinization and shows the starch dispersion viscosity is reaching the highest level, and the third at 92.5-121℃ which is for post-gelatinization of starch and shows the decrease in starch dispersion viscosity. This decrease relates to granules rupturing basically due to temperature increasing to the 121℃. For the simulation in this study, the two factors of inlet velocity of the fluid (0.5 and 1m/s) and inner tube diameter (inner tubes 4 and 8 cm) were considered. The lethality and F-value were calculated simultaneously with simulation in COMSOL software. The COMSOL 5.3a was used for simulation. The general alpha method and backward Euler time steps were used for solving the laminar flow and mass transfer equations. The geometry consists of a double tube heat exchanger of 2m in length. The outer tube diameter was 18cm. The steam with 121℃ is assumed as the heating medium for sterilization. 3.5% starch dispersion with an inlet temperature of 40℃ was used. The mesh quality in the simulation was 0.8. the tube material was stainless steel. The vapor is injected between two tubes. The lethality and F-value for Clostridium botulinum spores were calculated numerically. The simulated graphs and temperature were extracted from COMSOL after validation of the simulated data. The heat resistance of the inner tube and cooling phase was ignored. It was assumed that the fluid is hemogenic, and the velocity near the wall is zero.

The changes in diameter and fluid inlet velocity had a significant effect on lethality and F-value. Reducing the inlet velocity leads to increasing the lethality. When the diameter of the inner tube was 4cm, the lethality in lower velocity shows a 3-fold increase. While the lethality at the inner diameter of 8cm was 6.5-fold which is considerable. This shows despite fluid flow, changes in tube diameter have a high effect on microorganisms’ lethality. When the inlet velocity was low, the temperature changes during the tube length were low but finally, at the end of the exchanger, the changes in temperature were high. This shows when the fluid velocity reduces, the needed holding time for reaching a determined temperature will be achieved. Temperature also is a function of the starch dispersion viscosity. The viscosity of starch at the first parts of the tube increases due to gelatinization. But after, from the center to the end of the tube the viscosity decreases. These changes in viscosity are a result of gelatinization and pos-gelatinization of starch. The heat leads to starch gelatinized in the first part of the tube and the temperature changes were high due to inconsistency of viscosity in all layers of fluid. When the diameter of the inner tube and the inlet velocity of the fluid increased, the increase of viscosity happened in total flow. Finally, the simulated data show that the changes in fluid viscosity in different places in a heat exchanger led to changes in temperature distribution and finally changes in the sterilization process. This is important when the fluid viscosity change with temperature or other unit operations combined with temperature.

The results show both factors of inner tube diameter and inlet fluid velocity have a significant effect on the temperature profile of fluid and the lethality and F-value of aseptic sterilization. Especially the flow behavior is a function of the tube diameter. This is important when the starch is a broken heating fluid and its viscosity changes during the heating process. These viscosity changes in the starch fluid are also dependent on temperature profile and show very exact calculations for lethality. The changes in inlet velocity of fluid, temperature, pumping conditions, and tube diameter are the most important factors that affect the viscosity of food fluids. This study shows that simulation of fluid behavior during heat processing is important before designing and manufacturing the food machinery. This can be helpful for reducing the challenges during unit operations, and errors, and can assure the sterility of the final food product.Keywords: Numerical simulation, Aseptic, Double tube heat exchanger, Lethality

Garlic (Allium sativum L.), is one of the most perennial spice crops, which is grown all over the country and especially in plains of India and is used as the spices or condiment throughout the world. Fresh garlic clove has a high moisture content of around 70%, which can be easily spoiled due to microbial contamination also sprouting and rotting are the main causes of losses during storage (Zhou et al. 2017; Malakar et al. 2021). Drying is an energy-intensive unit operation in food preservation, as it removes the excess moisture content and enhances the shelf life of food products (Salehi 2020b). Garlic has found uses in its dried form, as an ingredient of precooked foods and instant convenience foods including sauces, gravies and soups, has led to a sharp increase in the demand of dried garlic (Sharma and Prasad 2006). Infrared radiation (IR) is developed in recent years with the advantages of higher puffing rate, energy saving, and uniform temperature distribution giving a better quality (Salehi 2020b). When exposed to infrared rays, samples absorb the radiation, leading to uniform molecular heating without impacting the temperature of the air in the drying chamber. As a result, drying rates are improved, foods are dried faster, energy consumption is decreased, and product quality is greatly preserved (Doymaz et al. 2015). Artificial neural network (ANN), known as connected machine model, which can simulate the basic process of biological nervous system to deal with external things. It was a computing system, which developed based on modern neuroscience, computer science, biology, and other disciplines, and it can simulate the human brain and nerve tissue (Saffari et al. 2009; Salehi 2020a). The ANN has attracted the attention of scholars in many fields due to its good fault tolerance and excellent nonlinear approximation ability of self-learning and self-organization. The structure of the ANNs model is formed using experimental data under consideration and therefore can represent and predict the data with high accuracy. ANNs has been used for modeling drying kinetics, with high accuracy (Onwude et al. 2016; Satorabi et al. 2021). In this study, the effect of the infrared treatment time, the samples distance from the infrared lamp (at three levels of 5, 7.5 and 10 cm) and the samples thickness (at three levels of 3, 6 and 9 mm) on the change in the moisture content of garlic slices inside an infrared dryer was investigated.

Slices of garlic (at three levels of 3, 6 and 9 mm) were prepared with the aid of a cutter. The garlic slices were dried in an infrared dryer (250 W infrared radiation lamp (NIR), Noor Lamp Company, Iran). The weight changes of garlic slices was measured by using Lutron GM-300p digital balance (Taiwan, the sensitivity of ±0.01 gr). All measurements were done in triplicate. In this study, the Neurosolution software (release 5, NeuroDimension, Inc., USA) was employed for making the ANN model. The experimental data order was first randomized and then total data were randomly separated into 3 partitions: training (20%), validating (20%), and testing data (60%). The testing data were used for prediction of the trained network performance on unseen data. In the hidden layers and output layer a hyperbolic tangent activation function was used. The Levenberg–Marquardt (LM) optimization method was applied to network training. Also, a sensitivity analysis was done to supply the measure of relative significance between the inputs of the ANN model and to show how the model output changed in response to input changes.

The results showed that by reducing the samples distance from the infrared lamp and also reducing the samples thickness, the amount of removed moisture from the samples increases and the drying time decreases. The time required to reach the moisture content of garlic slices with a thickness of 9 mm to about 10% at distances of 5, 7.5, and 10 cm was 50, 54, and 64 minutes, respectively. Also, the time needed to drying of garlic slices with thicknesses of 3, 6, and 9 mm was 28, 33, and 40 minutes, respectively (the distance between the samples and the radiation lamp was 10 cm). This process was modeled by an artificial neural network with 3 inputs (the treatment time by infrared, the samples distance from the infrared lamp and the samples thickness) and 1 output (moisture content). The results of artificial neural network modeling showed that the network with 12 neurons in a hidden layer and using the Hyperbolic tangent activation function can predict the moisture content of garlic slices during drying by infrared dryer (r=0.964). Also, the values of mean squared error (MSE), normalized mean squared error (NMSE) and mean absolute error (MAE) for optimum network were 20.637, 0.070 and 3.494, respectively.

The use of artificial neural network approach for modeling the drying kinetic and moisture content changes of garlic slices helps in programming and developing smart control systems, which is very useful for automated food processing systems.

In most countries, especially developing and underdeveloped, bread has high nutritional importance. Bread provides 40 to 45% of bioavailable carbohydrates, is an essential source of proteins, and plays a vital role in the digestive system (Aminpour and Shariatzadeh, 2013). Traditional Iranian bread is usually thin, flat and compact, and non-porous, and their bake has become commonplace in the past in Iran. The average per capita global consumption of bread is 60 to 70 kg. Large quantities of bread are wasted every year because different factors affect the number of waste products, including flour quality, bread production technology, and the storage condition of the bread. Among the factors affecting the quality of the flatbread, technological factors, including the source and method of heating the dough and the type of baking bed, are very critical. Those factors affect the quality and staleness of the bread and the amount of energy consumed per ton of the produced flatbread. Cast iron baking bed is used in industrial flatbread production in Iran. The heat transfer coefficient of cast iron is high and accelerates the baking process, which leads to drying the bread instead of baking. Therefore, lack of deep baking will result in staling of bread. Baking bread on this bed increases its staling rate and leads to the transfer of the heavy metal from the bed to the dough and bread. The objective of this study was to introduce the new baking bed, improve existing systems and increase product quality and storability.

In this research, it has been attempted to replace the two new baking beds with a cast iron one. These new baking beds were circular earthenware and ceramic (Cordierite-Mullite). The circular earthenware has made from 50% of SiO2, 10% of Al2O3, and 40% of MgO, Fe2O3, and CaO. The formulation of Cordierite-Mullite was 5SiO2.2Al2O3.2MgO-3Al2O3.2SiO2. Thermal shock resistance, surface hardness, and bending strength of the circular earthenware and Cordierite-Mullite were evaluated. A rotary bread-baking machine with a size of 210× 210 cm and a height of 150 cm is selected to install the new beds and cast iron ones. After installing the baking bed, they were evaluated by baking the flatbread. Baking the flatbread was conducted with wheat flour (18% bran). For this purpose, the dough was prepared according to the common practices in the industry and baked by a skillful operator. The flatbread was also baked simultaneously in the baking machine on all the all using the same dough and was stored in double-layer plastic bags in the same conditions in the refrigerator. To examine the changes in the physical and sensory attributes over time in the same product and the differences between the flatbreads baked using different beds, the bread underwent mechanical tests (using instrumental measurements) and sensory evaluations (by an experienced panel) three times: on the 24, 48 and 72hr after baking. Thus, the quality measurements of the flatbreads (both mechanical and sensory) were conducted during the storage of the products so that the variations in the quality of the flatbreads over time were determined. A puncture test was performed to evaluate the mechanical properties of the flatbread. In performing the sensory evaluations, 15 semi-trained judges (from daily users of flatbread) were asked to assign scores from one (very bad) to 5 (very good) to each identified sensory attribute. Attributes were selected based on the quality criteria of the product according to the AACC standard 01/30-74 (American Association of Cereal Chemists, 2000). The sensory panel evaluated the product 24, 48, and 72hr after baking. In addition, based on the scores assigned to each listed attribute in the quality and customer acceptance evaluations of the flatbreads, weight coefficients were developed for each attribute. The overall acceptability of each type of flatbread was calculated separately for the data from each evaluation date. It is noteworthy that the criteria and environmental conditions for conducting the sensory evaluations were the same during all sensory evaluations. Finally, the total score for each type of flatbread, baked on each baking bed at each time point, was compared with each other, and the trends of changes in the quality of the bread were determined.

Bending strength of Cordierite-Mullite and circular earthenware plate in the three-point bending test were 23.5, and 9.3 kN, respectively, and their Fracture load was 5.3 and 2.8 kN, respectively. The bending strength of cast iron was higher, but the Cordierite-Mullite plate has enough strength for the baking process. Thermal shock resistance of the Cordierite-Mullite and cast iron beds during the baking operations was too high, and no strain was observed during the heating process at 300 to 35 ◦C for 12 to 14 h. Therefore, the thermal shock resistance, surface hardness, and bending strength of new beds during the baking operations were acceptable. The results showed that these beds were suitable for installation on the baking machine and had enough strength for a long baking operation. The quality index of bread baked on the circular earthenware, and Cordierite-Mullite beds were 4.5, 4.3, and 2.9 at 24, 48, and 72 hours after baking, respectively. It was 4.2, 4, and 2.7 for bread that were baked on the cost iron bed at the exact times, respectively. These results indicated the durability and satisfactory quality of bread baked on the circular earthenware and Cordierite-Mullite beds. The compression force of baked bread on the circular earthenware, and Cordierite-Mullite beds at 24, 48, and 72 hours after baking were 10.4, 12.6, and 16.9 N, 9.3, 13.2, and 18.8 N, respectively. Compared with the bread baked on a cast-iron bed, the compression or stiffness values on the two new beds were relatively lower, implying a good marketable, and shelf life of bread. These results showed that the baked bread on these new beds not only had higher quality but also had a longer shelf life.

In general, the results of the current study indicated that the circular earthenware and Cordierite-Mullite beds have acceptable thermal shock resistance, surface hardness, and bending strength. In addition, bread baked on these beds had higher quality and longer shelf life.

Chicken meat is considered as an easily available source of high-quality protein and other necessary nutrients which are essential for body functioning. In order to meet the consumers’ growing demands for high-quality protein, the poultry industry focused on selection of fast-growing broilers, which reach a body mass of about 2.5 kg within 6-week-intensive fattening. Relatively low sales prices of chicken meat, in comparison to other types of meat, speak in favor of the increased chicken meat consumption. In addition, chicken meat is known by its nutritional quality, as it contains significant amount of high-quality and easily digestible protein and a low portion of saturated fat. Composition of chicken meat can be influenced through modification of chicken feed composition (addition of different types of oils or essential oils, vitamins, microelements and amino acids), to produce enriched meat with functional ingredients (n-3 PUFA, carnosine, selenium and vitamin E). By this way, chicken meat becomes a foodstuff with added value, which, in addition to high-quality nutritional composition, also contains ingredients that are beneficial to human health. Eugenol is the major constituent [70% to 90%] in the aromatic oil extract from cloves (Syzygium aromaticum), also found in lower concentrations in cinnamon and other aromatic spices. In vitro, eugenol has been shown to have antibacterial, antifungal, antioxidant and antineoplastic activity. Butyric acid is a short-chain organic acid with a direct influence on stimulating the growth of enterocytes, as it is also used as an energy source for these cells. Thus, they help to improve intestinal integrity, acting as a barrier to pathogens and increasing nutrient absorption capacity, which consequently improves animal performance Butyric acid glycerides (mono-, di- and triglycerides of butyric acid) and are stable at pH and are therefore released directly into the intestine and being more efficient than the free butyric acid salts. The main aim of this research was to investigate the effect of adding glycerides of butyric acid and eugenol essence to the diet of broilers on meat chemical and qualitative properties.

To achieve this goal, 300 broiler chickens of commercial strain Ross 308 were selected in a completely random design. Six experimental diets including experimental diets containing two levels of butyric acid glycerides (0 and 0.2% w/w) and three levels of eugenol (0, 500, 1000 mg per kg of diet) and the control diet in the form of five replicates and 10 pieces. After 42 days, the broilers were slaughtered, cleaned, and fillets were moved to zip pack packaging, maintained at refrigerator until tests. The assays including chemical compounds, L*a*b* color parameters, volatile nitrogen substances (TVN) and thiobarbituric acid (TBA) were conducted on the fillets at programed times during 60 days of storgae. The data from the tests were analyzed by means of one-way Analysis of variance (one-way ANOVA) with SAS statistical software.

The results of the data analysis showed that the addition of eugenol along with glycerides of butyric acid in the diet of broilers had no significant effect on the moisture and ash content of the fillets (p>0.05), while fat and protein extent of some treatments decreased significantly (p<0.05). L* values of T3 (fed by 1000 ppm eugenol) and T6 (fed by 0.2% w/w butyric acid glycerides and 1000 ppm eugenol) samples were highest and lowest, respectively. The b* values of all enriched diets were higher than that of the control. There was no significant difference among a* of all samples. The reason for decreasing L* of the samples fed by glycerides of butyric acid was pertain to higher pH of them, which cause to increase the intracellular water content and increasing light absorbance of chicken fillets. Overall color difference (ΔE) of the fillets collectd from the chickens fed by only eugenol (T2) and only 0.2% w/w butyric acid glycerides (T4) were highest and lowest, respectively. TBA values were not affected significantly by treatments, whereas storage time had a significant influence. Treatments containing 0.2% w/w butyric acid glycerides and eugenol indicated relatively lower TBA value than other treatments, and with increasing eugenol contents TBA more decreased due to antioxidant components (carvacrol, thymol, etc) of the essence. Similar to TBA, TVN values of the fillets increased significantly during 60 days of storage, without significant observation among different treatments at the same time. Against to TBA, chickens fed by only eugenol showed a decreased TVN values compared to other treatments.

According to the results, adding eugenol and glycerides of butyric acid to the diet of broiler chickens decreased fat content of fillets, which maybe considered as a beneficial function. Redness of meat (a*) wich is attended by consumers was not greatly influenced by diet. Oxidative resistance of fillets measured by TBA assays relatively improved specially by feeding butyric acid glycerides. The fillets ghatherd from broilers fed by only eugenol showed to some extent reduced proteolytic activity during storage. Consequently, incorporation of eugenol and butyric acid glycerides to broilers diet could improve the chemical traits of fillets, and to select an appropriate diet other physicochemical, textural and sensory properties of the fillets should be determined. Also, other edible sections of broilers such as legs and individual muscles, physiological properties of carcass and gastrointestinal microbial flora can be evaluated to better understanding the diet changing effects.

Dunaliella salina unicellular alga belonging to the Chlorophyceae family has been introduced as a extensive source of carotenoids (Zenouzi et al., 2013; Mendiola et al., 2008). The Carotenoids are strong antioxidants and bright pigments, and for this reason are used as human food and aquatics diets pigments (Denery et al., 2004). Investigations have shown that increasing the drying temperature will decrease the volatile and phenolic compounds of algae, and by decreasing the drying temperature, the amount of these compounds in the algae will be increased (Ling et al., 2015). According to the other research, the amount of beta-carotene after drying has been greatly decreased in conventional drying methods. (Ihns et al., 2011; Karabulut et al., 2007). The supercritical drying is an extraction process, that the supercritical fluid is the extraction solvent and water is the soluble substance (Brown 2010). The advantage of this drying method is that it is possible to prevent vapor-liquid contact in the homogeneous phase. For this reason, the tensile stress caused by the capillary that occurs during the air drying process does not exist in supercritical drying, and protects the structure of the material (Namatsu et al., 1999). In addition, carbon dioxide easily reached to critical temperature (31.1°C), so operating at low temperature (significantly lower than common dryers) prevents thermal damage (Brown 2010). Also Ultrasonic power at low frequency (20 to 100 kHz) is used for bacterial inactivation, improving process speed, heat and mass transfer, and water removal. In addition, the phenomenon of cavitation occurs in this composition and it causes an increase in the micro-mixing and communication between the solvent and microorganisms, and as a result, water exit and bacterial inactivation are improved (Morbiato et al., 2019). Non-contact ultrasonic, such as airborne processes, in which there is no contact surface or liquid to connect the transducer and the desired surface, can be used in various applications, including food drying. This system in combination with the other methods can overcome the limitations. For example, high temperature drying can damage the components of the material (color, texture, volatile compounds, etc.), while the combination with airborne can decrease the temperature and thus reduce the drying time, and the quality of the product and its nutritional ingredients should be maintained. The present work focused on investigation of the kinetics and drying rate of the Dunaliella salina algae by the supercritical carbon dioxide method in combination with airborne ultrasonic power, as well as the modeling of drying using mathematical and response surface methods.

The studied algae in this research was Dunaliella salina, which was obtained from the Artemia & Aquaculture Research Institute of Urmia University. In this research, 2.8 grams of algae paste with a thickness of 3 mm was placed in the drying vessel and methanol was added directly to the sample as a co-solvent. And the Suprex (MPS/225) in combination by airborne ultrasonic was used. The vessel that used in devise was made by stainless steel 316. Face center design consisting of 20 experimental runs with six replications at the central point was utilized to determine the effects of three independent variables in three levels: -1, 0, +1. The independent variables were Pressure at three levels (80, 110, 140 bar), temperature at three levels (40, 50, 60 °C) and airborne ultrasonic power at three levels (0, 20, 40 w) and the samples were weighed in dynamic mode in 30 minute intervals. The software of Design-Expert 13.0.5 (Stat-Ease, Minneapolis, MN, USA) was used for design experiment, data analysis and surface responsible diagram.

In 80 bar of pressure, the reduction of moisture content was constant for 150 min in temperature of 40 °C and without ultrasonic power and then was reduced. In other treatment the reduction of moisture content was continued for 120 min. In this pressure, after 180 min the moisture content in 40°C reached to 52% and in 60 °C and 40 w ultrasonic power reached to 31%. In 110 bar of pressure, the lowest moisture reduction was reached to 44% at 40 °C and 20 w. and the highest moisture reduction was 33% at 60°C and 20 w. The moisture reduction was constant for 120 min in temperature of 40°C and 20 w, while in temperature of 60°C and 20 w, the moisture content was constant for 90 min. in pressure of 140 bar, the maximum of moisture content was in 40 °C and without ultrasonic power and the minimum moisture content was 22% in 60 °C and 40 w. These results are due to the low viscosity, high diffusion rate and the near-absence of surface tension of the supercritical fluid. These properties allow the supercritical fluid to easily penetrate into the micro pores and surface and internal cells. Furthermore, new pores or channels could have been made by the supercritical fluid (Lee et al., 2011). The Midilli et al. model was the best ftting model. The highest values of R2, and the lowest values of SSE and RMSE obtained for the Midilli et al. model were 0.99925, 0.00023 and 0.0004, respectively. In RSM modeling, the results show that the changes of pressure, temperature and ultrasonic power had significant effect on moisture ratio in weighting time. While the interaction effect of independent variables had no significant effect on the factors. and the model has been investigated linearly. In the drying rate curve, at the beginning, drying was increased with a great slope, and then the curve decreases with a lower slope. The lowest drying rate at a pressure of 80 bar was occurred, in temperature of 40°C and the without ultrasonic power. And the highest drying rate was observed, in 60 °C and 40 w. the lowest drying rate in pressure of 110 bar was occurred in 40°C and 20w.

According to the results, the supercritical carbon dioxide method in combination with airborne ultrasonic power was suitable for dunaliella salina drying at low pressure and temperature. But in order to reduce the drying time and final moisture content, the pressure, temperature and ultrasonic power can be increased.

Herbal teas can be used for various therapeutic or nutritional purposes, depending on the chemical constituents. Quality control of products containing medicinal plants is important. Today, consumers' desire for herbal teas that have good aroma, taste and sensory properties is increasing. Herbal tea ingredients include one or more herbal species that are combined to improve taste and increase health. Quality control of herbal teas, like other nutritional supplements, is important to ensure safety and efficacy. Current methods are chromatography-based and require sample preparation. In some countries, researchers have used the ultra spectral imaging method as a fast and non-destructive method for quality control of medicinal plants and herbal teas. In this research, the quantitative and qualitative control of five herbal tea bags including Chamomile, Fennel, Lavender, Spearmint and Thyme were conducted. In terms of the kind of the plant, the ash content, the essential oil and their active substance were determined. Microscopic tests were carried out to ensure the type of plant, total ash and acid-insoluble ash were done with the method introduced in the references. Extraction of essential oils was done by water distillation and analysis of essential oil and determination of the major compounds was done by gas chromatography (GC). The essential oil of each sample was diluted with normal hexane solvent at a ratio of 1 to 10 and injected into the gas chromatography with the following information: Agilent 7890A GC device, injection temperature 250°C, thermal programming 60-220°C, column type HP-5MS, nitrogen as carrier gas, flow intensity 2 ml/min, temperature increase speed 6°C per minute, column length 30 meters, internal diameter 250 microns and FID detector. The ionization voltage was 70 electron volts, the ionization method was EI, and the temperature of the ionization source was 250 degrees Celsius. The temperature program of the column was set as follows: the initial temperature of the oven was 50 °C and stopped at this temperature for 5 minutes, the thermal gradient was 3 °C per minute, the temperature increased to 250 °C and stopped at this temperature for 10 minutes, the temperature of the injection chamber was 290 degree Celsius and the carrier gas was used with a flow rate of 1.1 mm/min.: By micrographic study, compatibility of the herbal contents were confirmed in tea bags with Iranian Herbal Pharmacopoeia (IHP). According to the TLC tests results, Rf values of anethol in Fennel essential oil, linalool and linalyl acetate in Lavender essential oil, thymol and carvacrol in Thyme essential oil and carvone in Mint were 0.88, 0.3, 0.75, 0.55 and 0.5 respectively. Chamomile sample had not essential oil. The total ash and acid-insoluble ash were respectively 1% and 8% for fennel, 5% and 13% for lavender, Were2.03 % and 7.5%, respectively for chamomile, 2.5% and 8% for Spearmint and 1% and 11% for Thyme. Based on GC analysis, amount of anethole in the essential oil of fennel, carvone in Spearmint essential oil, thymol in Thyme essential oil and linalool in Lavender essential oil were 0.098, 0.621, 0.019, 0.164 gr/ ml respectively.Discussion and In recent years, people's approach to medicinal plants and their products has increased. Every year, 50% are added to people who turn to the use of medicinal plants. Participating in such a large market and creating and developing the herbal medicine industry requires special attention to the production, processing, quality enhancement, standardization and safety of these products. It should be noted that factors such as the age of the plant, place and time of harvesting, drying method, storage conditions, production process, packaging method, etc. are effective on the quality of the plant and of course its effects, and therefore quality control and standardization are important. Post-harvest processes of the medicinal plants are very important in the production cycle of herbal products. Preservation of color, smell, taste, chemical nature and quality of active substances of medicinal plants has always been important for researchers and many studies have been done in this regard in recent years. Choosing the right method for drying medicinal plants depends on the type of organ, its moisture content and the purpose of drying. Finally, in the newer technologies, the minimization of changes is focused on plant raw materials.According to the results, Rf values were corresponded with standard indicators mentioned in the references. The total ash and acid-insoluble ash of Fennel, Spearmint and Chamomile were also correspond with the values available in Iranian Herbal Pharmacopoeia (IHP) but the mentioned values for Lavender and Thyme were not in compliance with reference. It is recommended to carry out periodic tests on herbal products after entering the market (PMS) to ensure the proper quality of the products. The outcome of this study can help to establish quality parameters for the standardization of herbal teas at the supply level.Keywords: Thyme, Lavender, Chamomile, Fennel, Spearmint, Quality control, Herbal tea

In this study, the two-dimensional equations of energy, mass, and momentum were solved using Comsol Multiphysics 5.2 software for pasteurizing date syrup in polyethylene terephthalate (PET) packaging. The importance of date syrup has been quite studied before in terms of its valuable nutritional values (especially heat-sensible vitamins). Research has shown that the appropriate heating process is required to maintain these values. Modeling (especially numerical modeling) is a robust method to predict the product temperature profile at every sample point during the process. It accurately predicts the slowest heating zone (SHZ), which should be reached at the pasteurization temperature and remain quiet enough at that temperature. In this way, not only are resistant microorganisms deactivated and killed but the product's nutritional values are also maintained. Comsol Multiphysics was applied in this research to predict the accurate position of the slowest heating zone, the dominant heat transfer method, and fluid velocity.

Thermophysical properties are necessary for heat transfer models. We estimated thermal conductivity (k) using the Krischer model. This model estimates a more logical thermal conductivity because both series and parallel models are incorporated into this model. The ratio of parallel and series models was assumed to be the same (f = 0.5) in our research. Specific heat was modeled using a suit model based on the mass fraction of components and their specific heat by temperature through a parallel model. Density is measured using a defined volume container. For this purpose, a pycnometer was used, and its volume was measured using distilled water filled in. The weight of syrup divided into its volume gave the density. The surface heat transfer coefficient (h) was determined by unsteady temperature measurements. This method measured the temperature of an aluminum container exactly at the same size as the PET, and h was obtained using the slope of ln(T ±Tal) diagram. The container's geometry should be drawn at the first modeling stage. In our case, the container was a hard part as the container did not have a specific geometric shape and had a thickness with thermal resistance. Second, the physics based on appropriate equations were selected, followed by defining initial and boundary conditions. The density, thermal conductivity, and surface heat transfer values were 1376 kg/m3, 0.4 W/m℃, and 43 W/m2℃, respectively, and specific heat was temperature-dependent. Next, meshes were defined. In the present study, the number of meshes used in the model was 6532 triangular elements, 405 of which were in boundaries. There should be logical assumptions to be able to model a process. In our study, the assumptions of Ghani were used. Finally, the model was run. In the experimental part of this research, heating was performed at 70℃ for 3000 s. Then, the temperatures of different container parts and syrup were collected using a K-type thermocouple and a data logger. Finally, the collected data at different parts of the package were used to verify the model.

The comparison criteria between the predicted and experimental figures used to evaluate the goodness of fit (GoF), namely the correlation coefficient (r =0.999), indicated that the model was valid and we could benefit from the model results. The results showed that the cold point migrated towards the top of the container because of the high product viscosity and the big can geometry. In fact, the dominant way of heat transfer was conduction. The explanation is that when heat transfer is molecule-by-molecule, the position of the cold point migrates toward the top of the container as at the top boundaries. Therefore, vacuum condition at headspace is considered. The accurate position of the slowest heating zone was at r = 9.5 cm and z = 0. The fluid velocity was maximum near the can wall and at a lower height and minimum at the beginning and the end of the process due to less temperature gradient.The mean velocity value in this situation was 1.562 ×10 -7 m/s. The plots of fluid velocity versus container radius and height showed that by increasing the height, fluid velocity rose because the fluid warmed up and flew toward the top of the can. The velocity in the interior radius after about 50 min of the heating part was more than the wall vicinity because the warmed fluid migrated toward the top of the can would be immobilized, and heat exchange with the cold parts would occur there. As a result, the fluid with a lower temperature would return to the bottom. In this process, after about 50 min when the fluid around the wall reached the environment temperature, there would be a temperature gradient near the core with colder fluid and the wall, which resulted in higher fluid velocity. The results of fluid velocity during the heating time show that this factor would decrease by increasing heating time due to the reduction in a temperature gradient. Obviously, the minimum velocity would be at the beginning and the end of the heating process when the temperature gradient was minimum. Different velocity plots demonstrated that at the beginning times of the heating process, the maximum velocity was near the wall (r = 4.5 cm). In addition, at the end of the process, it was at the interior parts near the center (r = 0.5 cm) regarding the difference in the magnitude of the temperature gradient at different parts of the fluid. We can also compare heat transfer by conducting or combining conduction-convection in our model. The model showed that the maximum heat flux is 320 W/m2 for conduction and 30 W/m2 for the convection part. These figures indicate the importance of conduction in the date syrup sample is more than ten times convection. The magnitude of heat flux in both conditions after around 35 min and by temperature stabilization at 70℃ reduced dramatically.

The simulation showed that the required time for pasteurization was 35 min, and the cold point reached the autoclave temperature.