JOURNAL OF INNOVATIVE FOOD TECHNOLOGIES (JIFT)
Year:2018 | Volume:6 | Issue:1 |Papers Count:12

Drying is one of the conservation methods of food that reduces moisture through the simultaneous transfer of heat and mass. In this study, the drying kinetics of biodegradable film based on Carrageenan and using microwave was investigated as a new, fast and relatively inexpensive method and it was introduced as the most suitable mathematical model for describing drying kinetics. For this purpose, the prepared films were dried using microwave oven at 350, 500, 750 and 900 W. Also, 10 mathematical models were fitted to test data and their fitting quality was analyzed. The fitting quality of the proposed models was evaluated based on the parameters of the coefficient of explanation (R2), square mean square error (RMSE) of the square (χ 2). Comparison between different models showed that the Midley model could be the most suitable model for estimating moisture variations and describing the film drying behavior. The highest effective moisture penetration coefficient was also obtained at a power of 900 watts of 41. 7 × 10-4 and the lowest effective moisture penetration coefficient at 350 watts was found to be 2. 78-10. 5-5. The results showed that microwave power has an important effect on drying rate and drying time is decreased by increasing the dryer power. The initial drying rate at 900 watts 9. 8 g/min and it was 4. 3 g/min at 350 watts. The longest drying time was observed at 350 watts which lasted 425 minutes. Also, the drying time of films with this method was significantly reduced by 97% compared to the conventional method (at 25° C warm air).

The high viscosity of pure chitosan solution, limits the production of pure chitosan nanofibers. One approach to overcome this limitation is to mix some other natural biopolymers including proteins with chitosan solution. Visia ervili is a natural protein with low cost and high content of energy. The aim of this study was to produce chitosan visia ervili nanofibers via electrospinning. Firstly, chitosan/visia ervili solutions were prepared in trifluroacetic acid solvent. Secondly, nanofibers were produced at the voltage 20 kV and tip to collector distance of 15 cm. Then the fiber morphology, FTIR, and XRD patterns were investigated. According to the result, nanofibers had diameter average of 100 to 250 nanometers. Crystalline structure was decreased after production of nanofiber. In the next step, mint essential oil was encapsulated within chitosan/ visia ervili nanofibers. Finally, according to the results, the ratio of 20% was selected as the best ratio and the morphology, FTIR, XRD of the nanofibers investigated. Also, the release and storage stability of essential oil were examined. FTIR results confirmed the presence of peppermint essential oil in the prepared nanofibers. The encapsulation efficiency of the peppermint essential oil was 71%. Encapsulation of peppermint essential oil in chitosan-protein nanofibers increased the essential oil shelf life from 4 days to 16 days. According to the findings, hydrophobic bioactives such as mint essential oil could be encapsulated within chitosan/visia ervili electrospun nanofibers.

In recent years, much consideration has been paid to use of essential oils and aromatic plants with anti-oxidant and antimicrobial properties in the food and pharmaceutical industries because of increasing in consumers’ tendency in using foods without Chemical preservative. However, the essential oils are volatile compounds, sensitive towards heat and insoluble in water, which limits their application. Therefore, this study aimed to investigate the capability of encapsulation technique as a suitable method for protecting essential oil against environmental conditions and assessing the colloidal properties of nanocapsules. For this purpose, identification of active compounds of Citrus Limon L. essential oil was performed using Gas Chromatography (GC). Then, Oil-in-water emulsion with a ratio of 1: 4 Essential oils: coatings with chitosan and modified starch with different ratios (0. 5: 9. 5, 1: 9 and 1. 5: 8. 5 % w/v) using freeze drying method was prepared by sonication. The effect of different wall concentrations on the physical and chemical properties of emulsion and nanocapsules were measured. The results showed that increasing in chitosan concentration resulted in higher stability and viscosity of nano-emulsion prepared with 1. 5: 8. 5% chitosan: Modified starch. Nano-emulsion which coated with higher concentration of chitosan showed smaller droplets and more uniform size distribution than the other treatments. The study of nano-capsule properties determined a significant difference (P≤ 0. 05) based on the different ratios of wall materials on moisture content, encapsulation efficiency and particle size. The morphology of the nanocapsules confirmed that the capsules with higher encapsulation efficiency had smooth surfaces, without gaps and with the least porosity.

Drying process has a major effect on the color, odor and taste of fresh saffron. In this research, effect of traditional including sun and shadow drying and industrial drying methods such as electrical oven at 50 and 80 oC and microwave at 300 and 800 watt on the saffron of Kurdistan province for reaching the optimal condition, was investigated. Results showed that the drying methods had significant effects (p <0. 01) on the physiochemical, microbial and sensory properties of saffron. Crocin content for dried saffron with microwave at 800watt that was about 171 and for 300 watt was 263. 5 and with electric oven at 80 oC was about 220. 5, respectively, not only were higher than the acceptable level according to national standard of Iran (220), but also they were significantly higher than other methods (p <0. 01). The highest level of picrocrocin and safranal content were measured in samples dried with microwave at 800 watt (113. 75, 30. 25), electronic oven at 80 oC (115. 5, 29. 05), and shadow (105, 29. 35), respectively. The lowest levels of crocin (146. 5), picrocrocin (86. 7) and safranal (23. 4) were measured in sundried saffron. As microwave power level and electronic oven temperature increase, the crosin and picrocrocin contents of saffron increase significantly (p <0. 01). The lowest microbial load was found in saffron dried with microwave at 800 W and then sunlight (p <0. 01). Overall, sensory attributes were ranked highest for the samples dried with microwave at 800 W and electronic oven at 80 oC, respectively. However, microwave drying at high power at 800 watt in comparison to other methods, could be the best drying method for saffron due to several advantages including reducing the drying time, keeping qualitative characteristics, decreasing microbial contamination and obtaining the highest score in organoleptic evaluation of dried saffron.

Purification is one of the main step in the sugar production, in which the purity of the raw juice increases by elimination of impurities. In this study, the efficiency of pectinase enzyme was studied to remove the pectic substance and improve the quality of raw sugar beet juice. Therefore, the effect of enzymatic pre-treatment in combination with lime treatment (4-20 kg/m3) on purification indexes (viscosity, turbidity, color, purity and colloid concentration and total proteins) was investigated. The results showed that the combination treatment significantly reduced the viscosity in comparison with the conventional purification process. The removal efficiency of colloidal and proteins was also facilitated by enzymatic treatment. In addition, the results showed that the improving of purity was approximately equal in the combined treatment of 8 kg/m3 with lime treatment of 20 and 30 kg/m3, and did not show significant differences (P 50%) and save the cost of sugar production.

Roasting is one of the important processing methods which is widely used in the nut industry to improve the flavor, color, texture and overall acceptability. In this study, four different roasting methods (superheated steam, hot-air, frying and infrared) were applied to roast wild almond kernels. Effect of processing conditions including air and oil temperatures (160 and 180° C), infrared power (200 W, 300 W) during roasting (15, 25 and 35 min) on moisture content, chemical properties, color and sensory properties were investigated. The results showed that increasing the temperature in hot air roasting, infrared power and roasting time decreased pH and the moisture content. The highest moisture content and acidity was for superheated steam and infrared roasting, respectively. Frying roasting showed the highest total acceptance while infrared roasting (300 W and 35 time) showed the minimum acceptance. Finally, infrared (200 W, 15 min), hot-air (160 ͦ C, 15 min) and frying (160 ͦ C, 25 min) were the recommendable processes for the wild almond roasting.

Rosewater is one of the main products of rosa damascena and is a traditional long-lasting product in the Kashan region that has a global reputation. Regarding the use of rosewater in the treatment of rheumatic, cardiovascular, and also in the baking of different types of sweets and the preparation of ice creams, the main detection or adulteration of the produced rosewater is of particular importance. In this research, the ability to use an olfactory machine system (electronic nose) based on metal oxide semiconductor sensors as a non-destructive tool for detecting different levels of adulteration in rosewater and its authenticity assessment was studied. Principal component analysis (PCA), linear discriminant analysis (LDA), loading analysis, support vector machine (SVM) and decision tree (DT) were the methods used to achieve this goal. Based on the results, the PCA with the two main components of PC1 and PC2 described 92% of the variance of the data set for the used samples. In the sensor array, MQ4, TGS2620 and FIS sensors revealed the highest loading coefficient values and TGS822 and MQ8 sensors devoted the lowest ones. Based on the results of LDA method, the accuracy of the classification was 94%. By use of support vector machine with linear kernel function, in the C-SVM method, training and validation accuracy were obtained 98. 75% and 87. 5%, respectively. Also, the accuracy of the decision tree method in the classification of samples of rosewater was 80%. Based on the results, the olfactory machine system based on MOS sensors in combination with the pattern recognition methods has the ability to detect adulteration in rosewater and the LDA method has the highest classification accuracy. The research team also suggests using the system ability to detect adulteration in other products with potential for adulteration.

The importance of chicken meat as a safe and nutrient food product is considerable for people all over the world. So checking of its quality has the great value. Therefore, the main objective of the current study is the diagnosis of chicken meat freshness using the estimation of elapsed time from slaughter helping of image processing and response surface methods. In order to achieve this goal, chicken thighs were selected as the case study and they were stored in the fridge temperature and desired images were prepared at the specified times. After that statistical features of texture images were extracted of different color channels, by application of sensitivity analysis method, effective features were selected in elapsed time from slaughter. At the end response surface method was applied to design and optimize the regression models in order to estimate the elapsed time from slaughter. The applied statistical indicators for validation of optimized regression models include R-Squared، Adj R-Squared، Pred R-Squared، RMSE and Press RMSE. The value of these indicators for the with skin part of chicken meat (optimized) were obtained 0. 901, 0. 899, 0. 898, 27. 31 and 27. 44 and for the skinless part of chicken meat (optimized) were 0. 866, 0. 865, 0. 864, 29. 66 and 29. 7. The acceptable obtained results indicate that image processing and response surface methods have the ability to diagnosis the elapsed time from slaughter as well.

Pretreatment of osmotic dehydration in hot-air drying process is used with the aim of improvement in the nutritional, sensory and quality properties of the final dried product. In present study, the pretreatment of osmotic dehydration of quince slices and then hot air drying of it was performed. Osmotic dehydration was done in concentrations of 40, 45 and 50% sucrose and hot-air drying temperatures of 40, 50 and 60 ° C. The ratio of sample to osmotic solution and also the temperature of osmotic solution were considered as 1: 10 and 30 ° C, respectively. Mathematical modeling of hot-air drying process of quince was evaluated using models of Newton, Page, modified Henderson and Pabis, simplified Fick diffusion, Modified Page equation-II, two-term, Wang and Singh, and logistics. The fitting of the experimental data with models was done in order to determine the optimum model to describe the drying process, determination of effective diffusivity coefficient and activation energy. Drying time for untreated sample at 40, 50 and 60 ° C was 509. 671± 1. 527, 491± 1. 732 and 459. 500± 0. 707 min, respectively. In addition, for samples with pretreatment of osmotic dehydration, drying time at studied temperatures of air drying was decreased with increase of sucrose concentration in osmotic solution. Page model was determined as the best model for describtion of mass transfer kinetic during drying of quince. The concentration of 50% osmotic solution and temperature of 60 ° C resulted to effective diffusivity coefficient of 2. 817×10-10 (m2/s) and drying time of 286± 1. 413 min. Furthermore, effective diffusivity coefficient was increased with an increase in air drying temperature. The concentration of osmotic solution was also related inversely to activation energy. Sensory evaluation showed an increase in concentration of osmitic solution caused an increase in overall acceptability.

The aim of this study was investigation optimum conditions of four Iranian commercial pistachio kernels (Fandoghi, Ahmad Aghaei, Akbari and Kale Ghoochi cultivars) infrared roasting. The roasting process was optimized by response surface methodology. Optimization was done by central composite design for every cultivar separately. The independent variables were infrared lamp voltage (V) and sample-lamp distance (m). The responses were chosen based on different aspects of quality factors: texture, color, taste, and time of roasting. For texture, the first and second fracture point; for color, browning index (BI); for taste, roasting taste; and for time, the roasting time to 2% moisture samples. The samples first fracture point were in range 20-40/5 N, second fracture point were in range 37-55 N, browning index were in range 38-41, roasting taste score were in range 4-9/12, and roasting time were in range 127-746 S, in the optimum points. A full quadratic model was fitted for responses by considering trial and error. The fitted model was significant based on ANOVA and R2. At last, results shown optimized points were different for every cultivar. The fitted model and experimental responses had a good correlation ( P ≤ 0. 05). Considering final products quality, it seems that pistachio kernels IR roasting can be a useful method to pistachio nut kernel roasting and can reduce the process time, at least 50%.

Tomato is the second most important crop in the world, which is often consumed freshly. One of the most importance tomato products is paste that considered being the stuffing ingredient in Iranian foods. Therefore, the safety of tomato paste is so important. The aim of this study was diagnosis adulteration in tomato paste. For this purpose, olfactory machine system based on five gas sensors (TGS2600, TGS2620, MQ3, TGS880, TGS2610) was constructed and its potential was evaluated in determining the different levels of pumpkin adulteration in tomato paste (0, 5, 10, 15 and 20%). Pure tomato paste detection from adulteration samples was based on the samples smell in the head space and the receipt of smell by sensors. The principal component analysis (PCA), linear discriminant analysis (LDA), support vector machine (SVM) and partial least squares (PLS) were used to classify and analyze the extracted features of the sensor response. Results of PCA and PLS indicated that 99 and 94 percent of data variance was covered by two main components. TGS2610 and MQ-3 sensors and TGS880 sensor had the highest and lowest application in detection of tomato paste adulteration. The accuracy of the classification by the LDA method was 79. 7%. The polynomial function with accuracy of 77. 78% of the training and 76. 66% validation in the C-SVM method and the radial base function with a precision of 98. 8% of the training and 88. 14% of Validation in the Nu-SVM method had the highest classification accuracy. In total, the olfactory machine system had acceptable performance in separation of different levels of adulteration.

Film forming capabilities of gelatin as well as chitosan have been used as edible films with suitable physical and mechanical properties in the packaging and food preserving industry. In this study, the effect of various chitosans (water-soluble, acid-soluble, oligosaccharide) was investigated with ratio of 50: 50 chitosan-gelatin. The latter was extracted from farmed Huso huso skin. In order to evaluate the effect of chitosan kinds in combination with gelatin extracted from the fish, physical, mechanical experiments, and then optical and infrared spectroscopic tests, and thermal characteristics of the films were assessed. In this study, the highest tensile strength and elongation at break point was obtained in films containing 100% gelatin and 50-50% soluble chitosan and gelatin one, respectively. In the chitosan oligosaccharide film, the highest moisture and solubility was observed while in the pure gelatinous film the lowest amounts of them were portrayed. Regarding swelling rate results, all films (soluble in gelatin / chitosan) were dissolved, while the lowest percentage of swelling rate was found in the pure gelatinous film. The results of the water vapor permeability of the films showed that the gelatinous films combined with the acid-soluble and oligosaccharide chitosan showed the lowest and the highest permeability to water vapor, respectively. The optical properties and transparency of the films showed a significant difference. The results of the infrared spectroscopy indicated that the gelatin-chitosan oligosaccharide film due to the less breaking process and the stronger absorption of band in amide 1, demonstrated better properties. In addition, the thermal stability and the weighted remainder of the combined films were more than that of the pure gelatinous film, which can be attributed to the incorporation of chitosans in the film matrix.