Iranian Journal of Nutrition Sciences and Food Technology, 2013
Conclusions: The results of this study found that GA and PL are potential wall materials for the ... more Conclusions: The results of this study found that GA and PL are potential wall materials for the encapsulation of canthaxanthin using the spray-drying method.
Background and Objectives: Stock price prediction has become one of the interesting and also chal... more Background and Objectives: Stock price prediction has become one of the interesting and also challenging topics for researchers in the past few years. Due to the non-linear nature of the time-series data of the stock prices, mathematical modeling approaches usually fail to yield acceptable results. Therefore, machine learning methods can be a promising solution to this problem. Methods: In this paper, a novel machine learning approach, which works in two phases, is introduced to predict the price of a stock in the next day based on the information extracted from the past 26 days. In the first phase of the method, an automatic clustering algorithm clusters the data points into different clusters, and in the second phase a hybrid regression model, which is a combination of particle swarm optimization and support vector regression, is trained for each cluster. In this hybrid method, particle swarm optimization algorithm is used for parameter tuning and feature selection. Results: The accuracy of the proposed method has been measured by 5 companies' datasets, which are active in the Tehran Stock Exchange market, through 5 different metrics. On average, the proposed method has shown 82.6% accuracy in predicting stock price in 1-day ahead. Conclusion: The achieved results demonstrate the capability of the method in detecting the sudden jumps in the price of a stock.
Kinetic analysis and effect of culture medium and coating materials during free and immobilized c... more Kinetic analysis and effect of culture medium and coating materials during free and immobilized cell cultures of Bifidobacterium animalis subsp. lactis Bb 12
The purpose of this study was to evaluate feasibility of near infrared (NIR) spectroscopy with fi... more The purpose of this study was to evaluate feasibility of near infrared (NIR) spectroscopy with fibre optic probe for predicting fatty acids profile of Beluga caviar. Measurement was performed on 100 samples of Beluga. The wild caviar samples caught sturgeon comprised Huso huso. NIR calibrations were developed using partial least square regression (PLSR). Selected models for the estimation of fatty acids in this specie of caviar exhibited coefficients of determination for cross validation which ranged 0.81-0.91 % with root mean square errors of (RMSE) between 2.1 and 3.0. This information suggested that in general, NIR interactance spectroscopy could provide an opportunity to measure fatty acids contents of caviars.
It is important to improve the quality of the enzyme inulinase used in industrial applications wi... more It is important to improve the quality of the enzyme inulinase used in industrial applications without allowing the treatment to have any adverse effects on enzyme activity. We achieved preferential chemical modification of the non-catalytic domain of endoinulinase (EC 3.2.1.7) to enhance the thermostability of the enzyme. We used pyridoxal 5′-phosphate (PLP) to modify the more accessible lysine residues at
Many chemical changes in beer aroma occur during storage (aging), and monitoring these changes co... more Many chemical changes in beer aroma occur during storage (aging), and monitoring these changes could give guidelines to the brewers how to manage and control the brewing process to obtain the final product with a high stability in flavour after packaging. In this regard, our laboratory aimed at a research into the application of an electronic nose in order to get the fingerprint of the change of non alcoholic beer aroma during aging. Th discriminatory power of the sensor array of this system was evaluated. Principal Component Analysis (PCA) and Soft Independent Modelling of Class Analogy (SIMCA) techniques were used for this purpose. The results obtained can direct us to performing other parts of our project. Considering the discriminatory power of the sensor array used, we can develop the application of a specific electronic nose system by picking up the most effective sensors or ignoring the redundant sensors.
A fundamental study on the phase-solubility, storage stability and antioxidant activity of the in... more A fundamental study on the phase-solubility, storage stability and antioxidant activity of the inclusion complex of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) with canthaxanthin (CTX) biosynthesized by Dietzia natronolimnaea HS-1 in a continuous bioreactor was designed. A variety of in vitro chemical methods including reducing power (RP), nitrite-scavenging activity (NSA), and 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2'-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and hydroxyl radicals scavenging capacities was used to determine antioxidant activities of the CTX and CTX/HP-β-CD complex. Results revealed that the apparent stability constant of the inclusion complex was 669 M(-1) in a 1:1 stoichiometric ratio. The complexation of CTX with HP-β-CD significantly improved its water solubility and storage stability. An increased dose-dependent manner was found for the NSA and RP values of the CTX and CTX/HP-β-CD complex. The CTX/HP-β-CD complex showed higher scavenging capacity than native CTX against DPPH, ABTS and hydroxyl radicals. It can be used as a promising strategy to improve the food application of CTX.
Skim milk, milk fat, cumin powder, olive and fish oils used to produce fortified feta cheese with... more Skim milk, milk fat, cumin powder, olive and fish oils used to produce fortified feta cheese with 8.4% mixed fat and its chemical, textural and sensory analyses compared with control or low only milk fat (again at 8.4%)feta cheese during 2 months cold storage. The measured hardness and sensorial scores of fortified cheese became very close (with no significant differences) to control samples after 30 days of storage due to the use of respectively whey protein concentrate and cumin seed powder. Additionally, the rheological properties (storage modulus, loss modulus and loss tangent) of fortified cheese reached to 85% of the parallel parameters in control sample throughout the 2 months cold storage. Although the peroxide and thiobarbituric acid values of fortified cheese increased to some extent, it did not exceed the standard levels and sensory panel did not detect any fishy flavour and unpleasant aroma even after 60 days storage. The unsaturated and saturated fatty acids of fortified cheese after 0, 30, and 60 days of storage, respectively were 120, 124 and 156% more and 27, 28 and 30% less than the similar values in control. Since the fortified samples of feta cheese had 30 mg or 10% of daily dose of EPA and DHA, it can be used as a rich source of omega 3 instead of normal feta cheese.
... by E-nose 6 7 Authors 8 Mahdi Ghasemi-Varnamkhasti a,b *, Seyed Saeid Mohtasebi a, Maryam Sia... more ... by E-nose 6 7 Authors 8 Mahdi Ghasemi-Varnamkhasti a,b *, Seyed Saeid Mohtasebi a, Maryam Siadat b, Jesus Lozanoc, 9 ... 427 [48] S. Sohrabvandi, SM Mousavi, SH Razavi, AM Mortazavian, K. Rezaei, Alcohol-free 428 beer: methods of production, sensorial defects, and ...
The fish oil (FO), and fish oil powder (FOP) at 10 % of recommended daily intake (RDI) were used ... more The fish oil (FO), and fish oil powder (FOP) at 10 % of recommended daily intake (RDI) were used to make two types of fortified feta cheeses. The physicochemical, rheological and sensory properties of ripened samples at 0, 30, and 60th days of cold store (5°C) showed that the FO samples had a faster pH reduction, higher MSNF (milk solid non-fat) increase (p <0.05) and more pores formation. Storage (G') and loss (G") moduli for both samples decreased until the 30th day of cold storage and then increased until the end of the storage time but both of them were higher for FOP samples. The index of secondary lipid oxidation or thiobarbituric acid reactive substances (TBARS) of FO was lower than FOP samples. Although the polyunsaturated fatty acids of both samples were much higher than common feta cheese, their degradation in FO was less than FOP samples after storage. The sensory scores of FO were significantly higher than FOP sample (P <0.05), and it obtained up to 70 % of overall acceptability after 30 and 60 days storage for its better hardness, texture and flavor.
This study optimized the production formulation for fortifying Iranian UF-feta cheese with fish o... more This study optimized the production formulation for fortifying Iranian UF-feta cheese with fish oil. The effects of the formulation parameters of cheese fat (8, 12, 16%), fish oil (0.4, 0.8, 1.2%), whey protein concentrate (0.54, 1.08, 1.62%), cumin (0, 0.25, 0.5%) and storage time (0, 30 and 60 days) on the pH, nonfat milk solids, acidity, fat, protein, texture hardness, peroxide value and sensory properties were determined using response surface methodology. The optimum conditions were determined to be 8% cheese fat, 0.4% fish oil, 0.72% whey protein concentrate, 0.5% cumin and 30 days of storage time. Practical Application Iranian UF-feta cheese made from bovine milk is manufactured in modern dairy plants from ultrafiltered and pasteurized milk with mesophilic starter cultures and commercial microbial rennet. The main characteristics of this cheese are about 35% (w/w) total solids, 6% protein content (w/w), 16% fat content and a maximum pH of 5.2. Substitution of milk fat with a combination of oleic acid and fish oil is a good nutritional strategy to reduce the intake of saturated fatty acids in favor of healthier fatty acids.
ABSTRACT The fish freshness was evaluated using machine vision technique through color changes of... more ABSTRACT The fish freshness was evaluated using machine vision technique through color changes of eyes and gills of farmed and wild gilthead sea bream (Sparus aurata), being employed lightness (L*), redness (a*), yellowness (b*), chroma (c*), and total color difference (ΔE) parameters during fish ice storage. A digital color imaging system, calibrated to provide accurate CIELAB color measurements, was employed to record the visual characteristics of eyes and gills. The region of interest was automatically selected using a computer program developed in MATLAB software. L*, b*, and ΔE of eyes increased with storage time, while c* decreased. The a* parameter of fish eyes did not show clear a trend with storage time. The L*, b*, and ΔE of fish gills increased with storage time, but a* and c* decreased. Regression analysis and artificial neural networks approaches were used to correlate the eyes and gills color parameters with the time of storage and a strong correlation was found between color parameters and storage day. Gills color changes were more precise than those found for eyes in order to evaluate the fish freshness. However, the gills cover should be removed for taking the images and thus, the method is destructive and time-consuming. Therefore, the color parameters of fish eyes can be used as a green, low cost and easy method for fast and on-line assessing of fish freshness in food industry.
In fermented products containing Bifidobacteria, factors such as organic acid concentration and β... more In fermented products containing Bifidobacteria, factors such as organic acid concentration and β-galactosidase activity are important in the development of flavor and texture of final products. Both the process conditions and medium components have significant effects on fluctuation of such factors. The effects of whey permeate powder and yeast extract concentrations, as nitrogen sources was investigated, on metabolic activity of Bifidobacterium animalis subsp. lactis Bb 12 in skim milk based media. Development of organic acids, growth rate and β-galactosidase activity under uncontrolled pH conditions was also monitored. Media with high concentrations of nitrogen sources showed maximum viable counts of B. animalis. The activity of β-galactosidase increased during the logarithmic phase and the initial stage of the stationary phase of growth and then decreased thereafter. Increasing the yeast extract concentration resulted in an increase in the specific sugar consumption rate with concomitant reduction in formation of acetic acid and formic acid. Consequently, the molar ratio of acetic acid to lactic acid was decreased. Using limited amounts of nitrogen sources resulted in more organic acid production in the tested microorganism. During the early hours of fermentation in which the amounts of nitrogen levels were limited, the specific rate of β-glactosidase activity was very high. Therefore, by evaluating the activity of this enzyme we can estimate the amount nutrient components in the medium.The production of succinic acid was observed during logarithmic and stationary phase in all fermentation media. Citric acid that naturally exists in whey and skim milk powder was consumed during the stationary phase of growth by B. animalis and its consumption correlated significantly with the production of succinic acid at this stage.
The compositions and structures of bovine and camel milk proteins are different, which define the... more The compositions and structures of bovine and camel milk proteins are different, which define their functional and biological properties. The aim of this study was to investigate the effects of enzymatic hydrolysis of camel and bovine whey proteins (WPs) on their antioxidant and antimicrobial properties. After enzymatic treatment, both the antioxidant and the antimicrobial activities of bovine and camel WPs were improved. The significantly higher antioxidant activity of camel WPs and their hydrolysates as compared with that of bovine WPs and their hydrolysates may result from the differences in amounts and/or in accessibilities of antioxidant amino acid residues present in their primary structures and from the prevalence of alpha-lactalbumin and beta-lactoglobulin as proteolytic substrates in camel and bovine whey, respectively. The results of this study reveal differences in antimicrobial and antioxidant activities between WP hydrolysates of bovine and camel milk and the effects of limited proteolysis on these activities.
Iranian Journal of Nutrition Sciences and Food Technology, 2013
Conclusions: The results of this study found that GA and PL are potential wall materials for the ... more Conclusions: The results of this study found that GA and PL are potential wall materials for the encapsulation of canthaxanthin using the spray-drying method.
Background and Objectives: Stock price prediction has become one of the interesting and also chal... more Background and Objectives: Stock price prediction has become one of the interesting and also challenging topics for researchers in the past few years. Due to the non-linear nature of the time-series data of the stock prices, mathematical modeling approaches usually fail to yield acceptable results. Therefore, machine learning methods can be a promising solution to this problem. Methods: In this paper, a novel machine learning approach, which works in two phases, is introduced to predict the price of a stock in the next day based on the information extracted from the past 26 days. In the first phase of the method, an automatic clustering algorithm clusters the data points into different clusters, and in the second phase a hybrid regression model, which is a combination of particle swarm optimization and support vector regression, is trained for each cluster. In this hybrid method, particle swarm optimization algorithm is used for parameter tuning and feature selection. Results: The accuracy of the proposed method has been measured by 5 companies' datasets, which are active in the Tehran Stock Exchange market, through 5 different metrics. On average, the proposed method has shown 82.6% accuracy in predicting stock price in 1-day ahead. Conclusion: The achieved results demonstrate the capability of the method in detecting the sudden jumps in the price of a stock.
Kinetic analysis and effect of culture medium and coating materials during free and immobilized c... more Kinetic analysis and effect of culture medium and coating materials during free and immobilized cell cultures of Bifidobacterium animalis subsp. lactis Bb 12
The purpose of this study was to evaluate feasibility of near infrared (NIR) spectroscopy with fi... more The purpose of this study was to evaluate feasibility of near infrared (NIR) spectroscopy with fibre optic probe for predicting fatty acids profile of Beluga caviar. Measurement was performed on 100 samples of Beluga. The wild caviar samples caught sturgeon comprised Huso huso. NIR calibrations were developed using partial least square regression (PLSR). Selected models for the estimation of fatty acids in this specie of caviar exhibited coefficients of determination for cross validation which ranged 0.81-0.91 % with root mean square errors of (RMSE) between 2.1 and 3.0. This information suggested that in general, NIR interactance spectroscopy could provide an opportunity to measure fatty acids contents of caviars.
It is important to improve the quality of the enzyme inulinase used in industrial applications wi... more It is important to improve the quality of the enzyme inulinase used in industrial applications without allowing the treatment to have any adverse effects on enzyme activity. We achieved preferential chemical modification of the non-catalytic domain of endoinulinase (EC 3.2.1.7) to enhance the thermostability of the enzyme. We used pyridoxal 5′-phosphate (PLP) to modify the more accessible lysine residues at
Many chemical changes in beer aroma occur during storage (aging), and monitoring these changes co... more Many chemical changes in beer aroma occur during storage (aging), and monitoring these changes could give guidelines to the brewers how to manage and control the brewing process to obtain the final product with a high stability in flavour after packaging. In this regard, our laboratory aimed at a research into the application of an electronic nose in order to get the fingerprint of the change of non alcoholic beer aroma during aging. Th discriminatory power of the sensor array of this system was evaluated. Principal Component Analysis (PCA) and Soft Independent Modelling of Class Analogy (SIMCA) techniques were used for this purpose. The results obtained can direct us to performing other parts of our project. Considering the discriminatory power of the sensor array used, we can develop the application of a specific electronic nose system by picking up the most effective sensors or ignoring the redundant sensors.
A fundamental study on the phase-solubility, storage stability and antioxidant activity of the in... more A fundamental study on the phase-solubility, storage stability and antioxidant activity of the inclusion complex of 2-hydroxypropyl-β-cyclodextrin (HP-β-CD) with canthaxanthin (CTX) biosynthesized by Dietzia natronolimnaea HS-1 in a continuous bioreactor was designed. A variety of in vitro chemical methods including reducing power (RP), nitrite-scavenging activity (NSA), and 1,1-diphenyl-2-picryl-hydrazyl (DPPH), 2,2&amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;amp;#39;-azinobis-3-ethylbenzothiazoline-6-sulphonic acid (ABTS) and hydroxyl radicals scavenging capacities was used to determine antioxidant activities of the CTX and CTX/HP-β-CD complex. Results revealed that the apparent stability constant of the inclusion complex was 669 M(-1) in a 1:1 stoichiometric ratio. The complexation of CTX with HP-β-CD significantly improved its water solubility and storage stability. An increased dose-dependent manner was found for the NSA and RP values of the CTX and CTX/HP-β-CD complex. The CTX/HP-β-CD complex showed higher scavenging capacity than native CTX against DPPH, ABTS and hydroxyl radicals. It can be used as a promising strategy to improve the food application of CTX.
Skim milk, milk fat, cumin powder, olive and fish oils used to produce fortified feta cheese with... more Skim milk, milk fat, cumin powder, olive and fish oils used to produce fortified feta cheese with 8.4% mixed fat and its chemical, textural and sensory analyses compared with control or low only milk fat (again at 8.4%)feta cheese during 2 months cold storage. The measured hardness and sensorial scores of fortified cheese became very close (with no significant differences) to control samples after 30 days of storage due to the use of respectively whey protein concentrate and cumin seed powder. Additionally, the rheological properties (storage modulus, loss modulus and loss tangent) of fortified cheese reached to 85% of the parallel parameters in control sample throughout the 2 months cold storage. Although the peroxide and thiobarbituric acid values of fortified cheese increased to some extent, it did not exceed the standard levels and sensory panel did not detect any fishy flavour and unpleasant aroma even after 60 days storage. The unsaturated and saturated fatty acids of fortified cheese after 0, 30, and 60 days of storage, respectively were 120, 124 and 156% more and 27, 28 and 30% less than the similar values in control. Since the fortified samples of feta cheese had 30 mg or 10% of daily dose of EPA and DHA, it can be used as a rich source of omega 3 instead of normal feta cheese.
... by E-nose 6 7 Authors 8 Mahdi Ghasemi-Varnamkhasti a,b *, Seyed Saeid Mohtasebi a, Maryam Sia... more ... by E-nose 6 7 Authors 8 Mahdi Ghasemi-Varnamkhasti a,b *, Seyed Saeid Mohtasebi a, Maryam Siadat b, Jesus Lozanoc, 9 ... 427 [48] S. Sohrabvandi, SM Mousavi, SH Razavi, AM Mortazavian, K. Rezaei, Alcohol-free 428 beer: methods of production, sensorial defects, and ...
The fish oil (FO), and fish oil powder (FOP) at 10 % of recommended daily intake (RDI) were used ... more The fish oil (FO), and fish oil powder (FOP) at 10 % of recommended daily intake (RDI) were used to make two types of fortified feta cheeses. The physicochemical, rheological and sensory properties of ripened samples at 0, 30, and 60th days of cold store (5°C) showed that the FO samples had a faster pH reduction, higher MSNF (milk solid non-fat) increase (p <0.05) and more pores formation. Storage (G') and loss (G") moduli for both samples decreased until the 30th day of cold storage and then increased until the end of the storage time but both of them were higher for FOP samples. The index of secondary lipid oxidation or thiobarbituric acid reactive substances (TBARS) of FO was lower than FOP samples. Although the polyunsaturated fatty acids of both samples were much higher than common feta cheese, their degradation in FO was less than FOP samples after storage. The sensory scores of FO were significantly higher than FOP sample (P <0.05), and it obtained up to 70 % of overall acceptability after 30 and 60 days storage for its better hardness, texture and flavor.
This study optimized the production formulation for fortifying Iranian UF-feta cheese with fish o... more This study optimized the production formulation for fortifying Iranian UF-feta cheese with fish oil. The effects of the formulation parameters of cheese fat (8, 12, 16%), fish oil (0.4, 0.8, 1.2%), whey protein concentrate (0.54, 1.08, 1.62%), cumin (0, 0.25, 0.5%) and storage time (0, 30 and 60 days) on the pH, nonfat milk solids, acidity, fat, protein, texture hardness, peroxide value and sensory properties were determined using response surface methodology. The optimum conditions were determined to be 8% cheese fat, 0.4% fish oil, 0.72% whey protein concentrate, 0.5% cumin and 30 days of storage time. Practical Application Iranian UF-feta cheese made from bovine milk is manufactured in modern dairy plants from ultrafiltered and pasteurized milk with mesophilic starter cultures and commercial microbial rennet. The main characteristics of this cheese are about 35% (w/w) total solids, 6% protein content (w/w), 16% fat content and a maximum pH of 5.2. Substitution of milk fat with a combination of oleic acid and fish oil is a good nutritional strategy to reduce the intake of saturated fatty acids in favor of healthier fatty acids.
ABSTRACT The fish freshness was evaluated using machine vision technique through color changes of... more ABSTRACT The fish freshness was evaluated using machine vision technique through color changes of eyes and gills of farmed and wild gilthead sea bream (Sparus aurata), being employed lightness (L*), redness (a*), yellowness (b*), chroma (c*), and total color difference (ΔE) parameters during fish ice storage. A digital color imaging system, calibrated to provide accurate CIELAB color measurements, was employed to record the visual characteristics of eyes and gills. The region of interest was automatically selected using a computer program developed in MATLAB software. L*, b*, and ΔE of eyes increased with storage time, while c* decreased. The a* parameter of fish eyes did not show clear a trend with storage time. The L*, b*, and ΔE of fish gills increased with storage time, but a* and c* decreased. Regression analysis and artificial neural networks approaches were used to correlate the eyes and gills color parameters with the time of storage and a strong correlation was found between color parameters and storage day. Gills color changes were more precise than those found for eyes in order to evaluate the fish freshness. However, the gills cover should be removed for taking the images and thus, the method is destructive and time-consuming. Therefore, the color parameters of fish eyes can be used as a green, low cost and easy method for fast and on-line assessing of fish freshness in food industry.
In fermented products containing Bifidobacteria, factors such as organic acid concentration and β... more In fermented products containing Bifidobacteria, factors such as organic acid concentration and β-galactosidase activity are important in the development of flavor and texture of final products. Both the process conditions and medium components have significant effects on fluctuation of such factors. The effects of whey permeate powder and yeast extract concentrations, as nitrogen sources was investigated, on metabolic activity of Bifidobacterium animalis subsp. lactis Bb 12 in skim milk based media. Development of organic acids, growth rate and β-galactosidase activity under uncontrolled pH conditions was also monitored. Media with high concentrations of nitrogen sources showed maximum viable counts of B. animalis. The activity of β-galactosidase increased during the logarithmic phase and the initial stage of the stationary phase of growth and then decreased thereafter. Increasing the yeast extract concentration resulted in an increase in the specific sugar consumption rate with concomitant reduction in formation of acetic acid and formic acid. Consequently, the molar ratio of acetic acid to lactic acid was decreased. Using limited amounts of nitrogen sources resulted in more organic acid production in the tested microorganism. During the early hours of fermentation in which the amounts of nitrogen levels were limited, the specific rate of β-glactosidase activity was very high. Therefore, by evaluating the activity of this enzyme we can estimate the amount nutrient components in the medium.The production of succinic acid was observed during logarithmic and stationary phase in all fermentation media. Citric acid that naturally exists in whey and skim milk powder was consumed during the stationary phase of growth by B. animalis and its consumption correlated significantly with the production of succinic acid at this stage.
The compositions and structures of bovine and camel milk proteins are different, which define the... more The compositions and structures of bovine and camel milk proteins are different, which define their functional and biological properties. The aim of this study was to investigate the effects of enzymatic hydrolysis of camel and bovine whey proteins (WPs) on their antioxidant and antimicrobial properties. After enzymatic treatment, both the antioxidant and the antimicrobial activities of bovine and camel WPs were improved. The significantly higher antioxidant activity of camel WPs and their hydrolysates as compared with that of bovine WPs and their hydrolysates may result from the differences in amounts and/or in accessibilities of antioxidant amino acid residues present in their primary structures and from the prevalence of alpha-lactalbumin and beta-lactoglobulin as proteolytic substrates in camel and bovine whey, respectively. The results of this study reveal differences in antimicrobial and antioxidant activities between WP hydrolysates of bovine and camel milk and the effects of limited proteolysis on these activities.
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