Food Engineering
Fatemeh Sabzmeidani; Masoud Taghizadeh; Mohammad Saleh Hemati Hasan Poor
Abstract
IntroductionIce cream is a frozen product, which is obtained from milk by adding compounds such as sweeteners, emulsifiers, stabilizers and flavoring agents. The structure of ice cream is a complex physicochemical system composed of three phases: liquid, solid and gas. Scientific results have shown that ...
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IntroductionIce cream is a frozen product, which is obtained from milk by adding compounds such as sweeteners, emulsifiers, stabilizers and flavoring agents. The structure of ice cream is a complex physicochemical system composed of three phases: liquid, solid and gas. Scientific results have shown that there is a connection between high fat consumption and cardiovascular diseases. Considering that ice cream is an almost fatty product and is particularly popular among people in the society, there is a greater demand for consuming low-fat varieties of this product. The food industry is also looking for new alternatives to minimize the negative effects of fat reduction on quality of ice cream. Hydrocolloids, are carbohydrate-based fat substitutes, which can mimic the mouthfeel and flow characteristics of fat cells due to their emulsifying and water binding capabilities. Eremurus luteus is one of the rhizome plants belonging to the Asphodelaceae family, cultivated around the world, including Iran. Cerise root gum is a new source of hydrocolloid with a glucose to mannose ratio of 1:1 to 1 from the family of glucomannans. The intrinsic viscosity of this gum was measured as 6.32 and 6.35 dl/g according to Huggins and Kramer equations, respectively, and it has the highest foam stability in concentrations of 0.2 to 0.5%. The rheological properties of cerise root gum have proven its important role as a new thickener, stabilizer and foaming agent.Materials and MethodsIn this research, sterilized and homogenized milk (1.5% fat) from Mihan Dairy Industries Company, sterilized and homogenized cream (25% fat) from Pegah Khorasan Dairy Industries Company, emulsifier 471 E from Beldom Belgium Company, powdered skim milk from Pegah company.Sugar and vanilla from confectionery store. Serish root gum was prepared according to the method of Salahi et al. (2020).The amount of ingredients required for the normal sample (high-fat control) was determined based on primary sources, including 10% fat, 11% fat-free milk solids, 12% sugar, 0.25% stabilizer, 0.15% emulsifier and 0.1% vanilla. According to the definitions for reduced-fat ice cream, 75% fat reduction was made from the normal sample (10% fat). In this regard, the investigated treatments were as follow: the amount of fat (2.5% fat: L), the type of gum (SRG) and the concentration of gum (at four levels: 0.2, 0.3, 0.4, 0.5%) compared to the control sample as high fat (10% fat: F).First, the liquid ingredients, including milk and cream, were continuously stirred while heating up to a maximum of 5 °C. After that, the mixture of solid materials (sugar, milk powder, gum, etc.) was added to the liquid part and mixed with a stirrer for three minutes after dissolving thes solids. The resulting mixture was pasteurized at 80°C for 25 seconds and homogenized with a homogenizer at 22,000 rpm for 1 minute and transferred to a water, salt, and ice bath and cooled to 50°C. Then, it was kept in the refrigerator at a temperature of 5°C for 24 hours. Finally, the mixture was transferred to a non-continuous ice cream machine for 15 minutes for the freezing stage, and the samples were poured into special containers with lids and coded, and placed in a freezer at -18 °C for at least 24 hours.Results and DiscussionBy adding gum and increasing its concentration, the amount of apparent viscosity, consistency coefficient, yield stress, plastic viscosity, textural characteristics (hardness, adhesion, continuity and apparent modulus of elasticity) increased. In the sensory evaluation section, the characteristics of creaminess, sweetness, viscosity, roughness, coldness and hardness were evaluated by transient dominant sensation test and these changes were significant in most cases. Sample containing 0.3% gum had the highest overall acceptance after the control sample compared to other samples. The results showed that these variables have the ability to simulate rheological properties (apparent viscosity, consistency coefficient, yield stress and plastic viscosity), melting speed and sensory characteristics such as creaminess, roughness, cryogenicity, viscosity, hardness and overall acceptance of the control sample with high fat as effective factors on the texture production process and the mouthfeel of the product in low-fat ice creams. On the other hand, due to the absence of significant differences between the data obtained from the pH and dry matter measurement tests, the applicability of Serish gum can be confirmed as a fat substitute.ConclusionThe examined samples all showed the loosening behavior with cutting. In the sample containing 0.2% gum, the melting speed increased (from 0.32 to 0.39), also with the increase in the amount of gum in the samples, the freezing temperature decreased by one degree Celsius (from39.4 to 39.5). Overall acceptance, pH and dry matter did not change significantly, which indicates the usefulness and applicability of this method. Also, regarding the rheological characteristics, the highest consistency coefficient in the 0.5% gum sample was 2.2605, similarly, the highest yield stress was in 0.5% gum sample and was 6.7076 pa. Similarly, the highest amount of Plastic viscosity and apparent viscosity belonged to the sample containing 0.5% gum. It was also shown that in the rheological characteristics, with the increase in the amount of gum in the samples, the amount of the relevant parameter increased significantly, and in all these parameters, sample containing 0.2% showed a lower amount than the control sample.
Food Technology
Maryam Khosravani; Seyyed Moein Nazari; Gholamhasan Asadi
Abstract
Introduction In recent years, increasing consumer awareness of the dangers of consuming high-fat products, sensitivity to proper nutritional patterns and the impact of health factors has increased consumer demand for low-fat or free-fat foods. Scientific researchers have provided a great quantity ...
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Introduction In recent years, increasing consumer awareness of the dangers of consuming high-fat products, sensitivity to proper nutritional patterns and the impact of health factors has increased consumer demand for low-fat or free-fat foods. Scientific researchers have provided a great quantity of evidence between the consumption of high-fat products and the development of diseases such as obesity, hardening of the arteries, chronic hypertension, etc. Fat removal is not an easy task because fat, in addition to nutritional aspects, affect rheological and sensory properties such as mouth feel and texture properties of the final product. Using alternative materials that can be completely or partially replaced fat in the formulation of low-fat products by imitating the properties of fat is great important. Unlike fat, which its high consumption causes many problems; fiber can play a vital role in many of the nutritional, functional, and sensory properties of food products, Some types of fiber act as fat substitutes, while producing less energy, provide a large effect of fat function properties. Increasing consumption of easy-cook meat products such as sausages induced replacement the fat content in the formulation of these products, by fat substitutes such as maltodextrin. The aim of this study was to evaluate the chemical and sensory properties of low fat German sausages produced by maltodextrin. Materials and Methods In this study, 0, 6, 12, and 18% of fat was replaced by maltodextrin in the formulation of German sausage. The chemical and sensory properties were then investigated. Chemical properties including moisture, protein, ash, and fat were accomplished according to the ISIRI standard. Evaluation of sensory properties was done by 5-point hedonic method according to Click et al. (2006). Data analysis was performed using SPSS software in a completely randomized design with a 95% confidence level. Results and Discussion The results showed that with increasing the level of maltodextrin, the amount of moisture, ash, and starch of sausage samples increased significantly. As the concentration of maltodextrin increased, the protein content of the samples decreased. The highest protein content observed in the control sample and the sample contained 6% maltodextrin and in contrary, the lowest protein content was in the sample containing 18% maltodextrin and there was no statistically significant difference between the test samples (p>0.05). Changes in maltodextrin concentrations had a significant effect on the fat content of sausage samples so that with increasing the concentration of maltodextrin in the sausage formulation, the fat content of the samples decreased (p≤0.05). Also, with increasing the percentage of maltodextrin replacement in German sausage samples, the cooking yield decreased significantly (p≤0.05). In the evaluation of sensory properties, it was found that the use of maltodextrin reduced the score in all parameters studied so that the lowest score in terms of color, texture, flavor, and total acceptance of sausage samples was related to sample with 18% maltodextrin replacement. Conclusion The vital role of the effect of dietary fiber on improving and managing the health has been proven by researchers for many years. Due to the need to reduce fat in products such as sausages, which considered as a popular meat product and based on the results observed in the present study, it is recommended to use maltodextrin fiber at the level of 6% as a fat substitute in the formulation of German sausages.
Reyhaneh Dakhteh; Mohammadreza Khani; Shahriar Dabiriyan
Abstract
Introduction: Because of the relationship between fat intake and obesity and the incidence of cardiovascular diseases, the demand for low-fat products has been increased. There are several methods to produce low fat products, which one of these methods is the use of fat replacer. The present study was ...
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Introduction: Because of the relationship between fat intake and obesity and the incidence of cardiovascular diseases, the demand for low-fat products has been increased. There are several methods to produce low fat products, which one of these methods is the use of fat replacer. The present study was aimed to partial substitution of fat in table cream by Qodume shirazi (Alyssum homolocarpum) and Persian (Amygdalus scoparia) gums. Materials & Methods: The fat content of cream was decreased from 25% (in control sample) to 18% and 15%, and each of these gums were added to the low-fat cream formulation in 0.2%, 0.3%, and 0.4% (w/w), separately to make 12 treatments. All samples were examined for physicochemical (including pH, acidity, dry matter, moisture, synersis, and viscosity) and organoleptic (including color, aroma, taste, texture and overall acceptability) properties. Results and Discussion: The results showed that the effect of type and amount of gums was significant for the pH, acidity, dry matter, moisture, syneresis, and viscosity of produced samples (P<0.05). In both types of cream (with 15 and 18 percent fat), pH of treatment containing 0.4% Qodume gum (6.81) was significantly higher than control (6.69) and other treatments (P<0.05). Moisture content of the control sample (68.7%) was lower than other treatments (73-78.7%) but dry matter of the control sample (31.3%) was higher than other treatments (21.2-26.9%) and in both creams containing 18% and 15% fat, the higher dry matter was devoted to sample containing 0.4% of Persian gum. The viscosity of cream with 18% fat containing 0.4% Qodume shirazi gum (21915 cP) and Persian gum (21919 cP) was significantly higher than the control sample (21507 cP) and other treatments. Moreover, syneresis of treatments with 18% fat containing 0.4% Qodume and Persian gums (0 ml), and also cream sample with 15% fat containing 0.4% Qodume gum (0 ml) was not observed as in the control sample (P>0.05). Evaluation of sensory properties revealed that the type of gums only had significant effect on color and the effects of cream type and amount of gums were mostly significant on texture and overall acceptance. In general, low-fat cream with 18% fat containing 0.4% Qodume and Persian gums had showed the best physicochemical and sensory results comparing to other treatments.
Sara Jamehdor; Sara Movahhed; Babak Ghiassi Tarzi
Abstract
Introduction: The cake is considered as the bakery products and has the different kinds with different calorie and often high calories in the kinds of cakes is due to the oil, eggs and sugar that is used in its formulation .In the present study the carbohydrate-based fat replacements are used instead ...
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Introduction: The cake is considered as the bakery products and has the different kinds with different calorie and often high calories in the kinds of cakes is due to the oil, eggs and sugar that is used in its formulation .In the present study the carbohydrate-based fat replacements are used instead of fats for consuming. The flaxseed with the scientific name of "Linum usitalissmum" is an annual plant from the family of flax and in terms of nutritional value it is a good source of omega-3 (alpha-linolenic acid, ALA), Lignans (such as phyto-estrogenic), fiber, protein, minerals and vitamins. The high amount of water absorption by flaxseed in bakery products leads to increase the volume and improve the quality of bread and also increase the shelf life of the product produced. The oat is a plant from the family of grains and from the genus of "Avena" called in English "Oat". One of the major compounds in the oat is β-glucan. The said compound is the common name of glucose polymers that is found in the endosperm cell walls of barley and oat and usually forms 3-7% of the seed weight and is classified as soluble dietary fiber and carbohydrate-based fat replacements. The purpose of this study was to add different levels of flaxseed and oat bran as a part of fat replacement in cake. Different Levels of shortening were replaced with Oat bran and flaxseed powder and their effects on the chemical characteristics, volume, color, staling and sensory characteristics of the cakes were examined.
Materials and methods: Raw materials needed to bake a cake included the null wheat flour (Mehbod Company) with extraction rate of 70%, sugar (Pardis Company), nonfat dry milk (IDI France Company), egg white powder (Talavang Company), table salt (Golha company), baking Powder (Golhan Company), oil (Ladan Company), flaxseed and oat bran (Sarv Company). Chemical tests performed on wheat flour, oat bran and flaxseed meal and samples of cakes included the measurement of moisture, ash, protein, fat, fiber, peroxide and pH were performed. For the production of cake the raw materials were prepared and were weighed. Then, the oil and sugar mixed for 2 minutes and then some water was added and mixed for 2 other minutes. Then, the null wheat flour, oat bran and flaxseed powder sieved with other materials were mixed. Finally, the cake was added to the mold and located in the tunnel oven at 170°C for 35 minutes for baking. in all the tests the control treatment (cake containing 100% fat and null wheat flour) with the code of C, the treatment containing the oat bran and flaxseed with the ratio of 20:40 (weight– weight of fat consumed) plus 40% of fat with the code of A1, the treatment containing the oat bran and flaxseed with the ratio of 40:20 (weight – weight of fat consumed) plus 40% of fat with the code of A2, the treatment containing the oat bran and flaxseed with the ratio of 30:30 (weight– weight of fat consumed) plus 40% of fat were determined with the codes of A3 revealed. The method proposed by Henry Simon British Company and device of volumeter were used to determine the volume of cake samples produced. The test of determining the color the Hunter Lab device was used. In order to determine the amount of staling of the cake samples, the device of evaluating the texture or Instron was used. In this study, examined by 10 trained evaluators was used for organoleptic test of samples. In determining the amount of staling in the cake samples produced the sensory method was used. This test was conducted at the intervals of 3, 7 and 10 days after baking of the samples. In order to investigate the quantitative characteristics of data considering to the presence of four treatments and three replications, randomized block design, the analysis of variance and the software "SPSS", version 16, were used.
Results & discussion: The amount of protein and fiber in treatment of A1 and in the control treatment was the highest and the lowest, respectively. In addition, the amount of ash and moisture in the treatment of A2 and in the control treatment was the highest and the lowest, respectively. The treatment of A1 and the control samples had the highest and the lowest amount of peroxide, respectively. Results of specific volume test indicated that the treatment of A2 and the control samples had the highest and the lowest amount of specific volume, respectively. The results of colorimetric test of cake samples indicated that the lightness (L*) in the control cake and in the treatment of A1 was the lowest and the highest amount, respectively. Moreover, the amount of redness in treatment of A1 and control treatment was the highest and the lowest, respectively. The amount of yellowness in the control treatments and treatment of A2 was the highest and the lowest, respectively. The results of evaluating the sensory characteristics of cake samples produced by panelists showed that most sensory characteristics of the cake samples containing flaxseed and oat bran compared with the control had higher rating. The results of staling test in the cake samples produced by sensory method showed that the control treatment had the highest amount of staling and the treatments of A1, A2 and A3 had the lowest amount of staling, respectively. The results of staling test using device method showed that the control treatment had the highest amount of staling and the treatments of A1 and A2 had the lowest amount of staling, respectively. Finally, the treatment of A2 was introduced as the best treatment. In the present study, oat bran and flaxseed seed were used as a part of carbohydrate-based fat replacements in the cake to produce a healthier products with less fat and better nutritional compounds while improving the qualitative characteristics.
Sima Shamsaei; Seyed Mohammad Ali Razavi; Bahareh Emadzadeh; Esmaeil Atayesalehi
Abstract
Introduction: An emulsion is made of dispersed particles through the continuous phase, while not dissolving happens between two phases. Mayonnaise is oil-in- water emulsion (James and Dakin, 1962), as one of the most sauces used in the world. It has a mild odor and taste, creamy to pale yellow color ...
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Introduction: An emulsion is made of dispersed particles through the continuous phase, while not dissolving happens between two phases. Mayonnaise is oil-in- water emulsion (James and Dakin, 1962), as one of the most sauces used in the world. It has a mild odor and taste, creamy to pale yellow color and a pH in the range of 3.6- 4.0, which does not exceed 4.1 (Iranian National Standard, No 2454). Emulsion products are naturally instable. Different factors such as temperature, particles size, stirring, mechanical movements, constituents’ concentration, presence or absence of stabilizers and thickeners may affect the emulsion stability (David, 1999). Ocimum basilicum L., known as basil (or ‘‘Reyhan” in Iran), is a common herb plant grown in Iran. Soaking in water, basil seeds become gelatinous. The high mucilage content of basil seeds can make it a novel source of edible gum (Razavi et al., 2008). The objective of this paper was to investigate the effect of basil seed gum as well as xanthan as fat replacers on some physical and rheological properties of low fat mayonnaise. Materials and methods: Emulsion stability determination: Mayonnaise samples were centrifuged at 5000 rpm for 30 minutes. Emulsion stability (ES) was then determined using the following relation (Worrasinchai S et al., 2006): Stability index= (Total volume/ Volume of emulsion remaining)100. Particle size measurement: Particle size distribution of low-fat mayonnaise samples was determined using laser light diffraction technique (Fritsch Analysette 22, Germany). Rheological measurements: A rotational viscometer (Visco 88, Malvern, UK) equipped with a thermal circulator was used to measure the steady shear rheological properties of samples at the shear range of 14-300 s-1 and constant temperature of 25 oC. Power law, Bingham, Casson, and Herschel-Bulkley models were fitted on the experimental data and the rheological parameters of these models were determined using Slidewrite plus-bar Graph software (1983, Advanced Graphics Software, Inc, USA). Image processing: A scanner was used to capture the samples’ image and the scanner resolution was set to 300 dpi. 7g sample was placed onto a plate and then 152×210 Pixel parts was cut from the obtained image. All images were stored in JPEG format for further analysis. The Clemex image processing software (Clemex Vision Professional, PE4, Canada) was used to determine the color parameters (L*, a* and b*). Results and Discussion: Steady shear flow behavior: The results showed that all samples are classified rheologically as non-Newtonian shear thinning fluids. According to R2 values, Power law was considered as the best rheological model to describe the flow behavior of samples. The maximum and the minimum consistency coefficients of Power law model were observed for the formulation containing 0.75% xanthan gum and 0.45% basil seed gum, respectively. In this study, the apparent viscosity of mayonnaise (in shear rate 42 s-1) raised with increasing gum concentration that this increase in samples 4 and 5 were not significant (P>0.01). The highest apparent viscosity was observed in sample 3 that was prepared with a concentration 0.75% of xanthan gum, while the lowest viscosity was related to sample 4 that was contained of 0.45% basil seed gum. With increasing gum concentration, Bingham viscosity of the samples increased, but this increase in the samples (1, 7, 8) and (2, 6, 9) was not significant (P> 0.01). Yield stress values of Herschel-Bulkley (τH), Bingham (τB) and Casson (τC) models raised with the increasing of gum concentration. Highest yield stress value was related to mayonnaise containing 0.45% xanthan gum and the lowest yield stress value related to mayonnaise prepared with 0.45% basil seed gum. Particle size distribution: Particle size distribution of mayonnaise at concentration of 0.6 % xanthan gum, basil seed gum and mixture of xanthan- basil seed gum had mono-modal particle size distribution. Emulsion stability: Among samples, formulations of 1, 2, 3, 8, and 9 were quite stable and there was no instability (two-phase state). Higher stability in emulsions containing xanthan gum was probably due to higher viscosity of this gum compared to basil seed gum. Color: The best color was observed in sample 6. In this study, with increasing concentration of gum in three samples (1, 2, 3), the amount of L* decreased, it means that the brightness of the product was reduced while in samples containing a mixture of gums (xanthan- basil seed gum), increasing the gum concentration resulted in an increase in L* parameter.
Seyed Mohammad Ali Razavi; Mostafa Mazaheri Tehrani; Bahareh Emadzadeh
Abstract
Introduction: Recently, consumers have directed their interest towards low fat products as they associated them with a reduced risk of well-known health problems such as obesity and coronary heart diseases. Fat is a multifunctional ingredient in ice cream system. Thus, in attempts to provide desirable ...
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Introduction: Recently, consumers have directed their interest towards low fat products as they associated them with a reduced risk of well-known health problems such as obesity and coronary heart diseases. Fat is a multifunctional ingredient in ice cream system. Thus, in attempts to provide desirable flavor and physical characteristics of full fat ice cream, manufactures looking for fat replacers (Drake et al. 1999). Hydrocolloids have functionalities such as thickening, gelling, fat replacing, which allow them to use in different industries (Roller and Jones, 1996; Williams and Phillips, 2000). Guar gum is used as a stabilizer in ice cream and provides smoothness in texture, retards ice crystal growth, and increases freeze-thaw stability (Wielinga, 2000). The rheological properties and potential of basil seed gum (Rayhan) as a novel stabilizer for structure formation and reducer for ice recrystallization in regular ice cream have been recently investigated (Hosseini-Parvar, 1388; Bahram-Parvar, 1391). In this research, the physicalproperties of light (5% fat) and low fat (2.5% fat) ice creams as a result of replacement of milk fat by guar gum (as a commercial hydrocolloid), basil seed gum (as a novel hydrocolloid) and their blend (50:50) at different concentrations were investigated and compared to those of control sample (10% fat). Materials and methods:The ice cream formulations were prepared based on the following composition: 2.5% (L), or 5% (R) or 10% (B) milk fat, 11% MSNF, 15% sugar, 0.1% vanilla, 0.15% emulsifierand 0.35%, 0.45%, 0.50% or 0.55% selected gums (guar gum, basil seed gum or blend (50:50) of them). Liquid materials including milk and cream were mixed together and warmed up to 50˚C. After that, the pre-weighed and mixed dry ingredients were dispersed into them, under agitation. The mixes were pasteurized at 80˚C for 25 s, homogenized at 23000 rpm for 2 min, cooled rapidly to 5˚C and then aged at constant temperature overnight (12 h) at 5˚C. The freezing was carried out in a batch soft ice cream maker. Apparent viscosity of ice cream mixes were evaluated using a rotational viscometer at 5˚C and 51.8 s-1. Before melting rate determination, samples were tempered at –18°C overnight, Ice cream samples (30 g) were put on a wire screen mesh and allowed to melt at ambient temperature. Melting rates were measured from the slop of linear portion of drained mass vs.time graphs. The pH values for mix samples were measured with a pH meter. After the mix was frozen in a batch freezer, Draw temperature of ice creams was obtained using a digital thermometer.Mix and ice cream samples (3 g) were diluted 1: 500 in two steps with deionized water and absorbance was measured by a spectrophotometer at 540 nm. Turbidity (%) was calculated as (absorbance in mix - absorbance in ice cream)/absorbance in mix 100%. A known volume of ice cream and mix were weight and overrun was determined as (weight of the mix - weight of the ice cream)/ weight of the mix 100%. Results & discussion: Reducing fat in any food formulation will cause a decrease in viscosity (Cody et al., 2007). Fat reduction decreased apparent viscosity (P0.05), ranging from 6.31 to 6.34. Draw temperature as a measure of freezing point of ice cream is dependent on the type and concentration of the soluble constituents and varies with the composition. Addition of some ingredients such as sweeteners, lactose and salts decrease the freezing point. Fat is immiscible with the aqueous phase and carbohydrate polymers are very large molecules, depression of the freezing point is caused indirectly by using of these materials, as a result of decreasing the water content (Marshall and Arbuckle, 1996). In this study, a reduction of fat content of full fat ice cream resulted in higher draw temperature. However, there was not a specific trend in the temperature values of samples with same fat content and different fat replacer levels. There was no significant difference between turbidity of samples with same kind of gum. Similar results were obtained by Schmidt et al. (1993), which related to sufficient amount of milk fat (2.1 and 4.8 %), milk proteins and emulsifiers in ice cream formulations. Conclution: Decreasing the fat content generally caused an increase in the value of overrun. But, very high viscosity of mix may prevent vigorous agitation and air incorporation that seems the reason of why increasing fat replacer concentration resulted in overrun reduction
