Maryam Mohammad Khani; Mohammad Fazel
Abstract
Introduction: Increasing society's desire to consume healthy and low-calorie foods has led to the production of low-fat and healthy foods. In this study, the effect of oil replacement with tofu cheese and Persian gum on physicochemical, textural, rheological and sensory properties of Mayonnaise sauce ...
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Introduction: Increasing society's desire to consume healthy and low-calorie foods has led to the production of low-fat and healthy foods. In this study, the effect of oil replacement with tofu cheese and Persian gum on physicochemical, textural, rheological and sensory properties of Mayonnaise sauce as well as its particle size, were investigated. Tofu was replaced with fat at three concentration levels of 20, 35 and 50% and Persian gum was added to the sauce at three concentrations of 2.5, 3, and 3.5%. The control sample contained 60% fat and guzanthan gum. With increasing tofu, pH and acidity increased and with increasing Persian gum acidity decreased. With increasing tofu, histological test (hardness, adhesiveness, adhesive force, work done to hardness, apparent modulus) decreased and with increasing Persian gum, their increased. With increasing tofu, decreased particle size. With increasing gum until 3%, average of particle size decreased and with more increase of gum, average of particle size increased. The rheological behavior of all samples at a shear rate of 0.01 to 1000 (on second) showed that the viscosity decreased with increasing tofu decreased and with increasing gum, increased. In all samples, with increasing shear rate, the viscosity was decreased, and the behavior of the samples was pyseudoplastic and the parameters followed the power law model. Sample with 20% tofu cheese and 3.5% Persian gum as top samples, whose properties are closer to fatty mayonnaise and can be called Mayonnaise with reduced fat. Materials and methods: Physical and thermal stability tests of the emulsion were performed with a centrifuge machine. PH test was performed using pH meter and acidity test in terms of acetic acid percentages. The fat percentage was performed with a Soxhlet. The texture properties were performed by back extrusion test and the parameters of hardness, adhesiveness, adhesiveness force, apparent modulus and force required to squeeze were calculated. The particle size was measured using a dynamic light dispersion apparatus, and the average particle size, mod, and D50 of the emulsion particles of oil were investigated. The rheological behavior was performed by the rheometer and sensory evaluation was conducted by the hedonic method. Statistical analysis was performed by using SPSS software and the mean comparison test at 5% probability level and in the form of factorial test. Results & Discussion: In the physical and thermal stability test of the emulsion, no two phases were observed in the samples. This could be due to the strong structure of the emulsion and the high viscosity of the continuous phase. By increasing the tofu value, the pH increased, which can be attributed to the decrease in the concentration of hydrogen ion or the increase of the aqueous phase. With increasing amount of gum, there is no change in pH, because the Persian gum has a neutral nature. Increasing the amount of gum did not affect acidity. As the tofu increased, acidity increased, and this increase was very slight, which can be attributed to buffering mode of tofu due to high amounts of high amino acids. By increasing the tofu percentage, the percentage of fat decreases because the percentage of fat in tofu cheese is law and its protein content is much. The increase in gum did not affect the amount of fat, because Persian gum structure was made up of saccharides. The tofu increase up to 35% reduced the texture properties, because the aqueous phase increased, with increasing gum percentage, texture properties increased because it produced a strong gel structure.With the increase in tofu content, the particle size of the oil decreased, because with increasing the amount of fat, the particle size increased. By adding gum the particle size decreased to 3% and then increased, because in the Persian gum structure, there are insoluble branches and the solubility of these branches is low. In the evaluation of rheological behavior, flow behavior test was investigated; viscosity of all samples was reported at shear rates of 0.1, 1, 10, 100/ sec. In all samples, the viscosity decreases with increasing frequency. By increasing the gum at a constant shear rate, the viscosity increased, which can be explained by the fact that the formation of a stronger structure in the presence of higher concentrations of gum. By increasing the shear rate at a constant concentration of gum, the viscosity decreased, and the increase in gum with increasing shear rate also reduced the viscosity and sauce had profit and plastic behavior that could be due to the opening of the bonds. As the tofu percentage increased in all shear rates, viscosity decreased and by increasing the tofu value at a constant shear rate, the viscosity decreased, and the increasing tofu with increasing shear rate reduced viscosity due to high moisture content of the cheese. The rheological parameters of mayonnaise sauce were checked in accordance with the power law. As the gum increased, the consistency coefficient increased , because the number of molecules with high molecular weight in the liquid phase increased, with increasing the percentage of tofu cheese, the coefficient of consistency decreased. The flow behavior coefficient does not have a clear trend, and since it is less than 1, the samples are non-Newtonian. In the strain scan test in lower strains, mayonnaise always has linear viscoelastic behavior. By increasing the gum concentration, both the elastic and viscous components are transported to higher values, which can be due to more interaction between the Persian gum and the components of the emulsion. In the sensory evaluation of the samples, the addition of gum and tofu percentage was not effective.With regarding the data of the tests, mayonnaise sample was identified with the replacement of 20% tofu cheese and 3.5% Persian gum as a superior sample, which its properties are closer to fatty mayonnaise and can be classified as Mayonnaise with law Fat. An extensive medicinal property of Persian gum with tofu cheese in mayonnaise sauce makes it a rich and very good source.
Laleh Golchoobi; Mazdak Alimi; Hossein Yousefi
Abstract
Introduction: Mayonnaise, a semisolid oil in water emulsion containing vegetable oil, vinegar, egg yolk and optional ingredients such as salt, sugar and mustard, is a conventional old condiment containing high fat ingredient (minimum of 65%). The need to reduce the amount of saturated fat in diets, has ...
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Introduction: Mayonnaise, a semisolid oil in water emulsion containing vegetable oil, vinegar, egg yolk and optional ingredients such as salt, sugar and mustard, is a conventional old condiment containing high fat ingredient (minimum of 65%). The need to reduce the amount of saturated fat in diets, has led to the development of alternative processes to produce law fat mayonnaise. Cellulose and its physically-treated derivatives i.e. microcrystalline cellulose (MCC) and microfibrillated cellulose (MFC) lately investigated as NFC is one of the conventional fat replacers used in low-fat products formulation such as mayonnaise. Nanofiber cellulose (NFC) is a glucose polymer connecting together by β (1-4) glycosidic bonds. This low-cost new kind of cellulose can be obtained from physical modification of cellulose as naturally occurring carbohydrate that is renewable, biodegradable and nontoxic. Increased specific surface area, enhanced mechanical and hydrophilic properties of nanoscale cellulose are affected by the number of hydrogen bond in nanofiber chain of cellulose and low concentration of NFC suspension can form a stront and viscous semi-gel network. As a result, because of all the functional properties, NFC can be employed as a fat replacer in reduced or low calorie food products, and as an improver of the product structure consistency. In fact, because of downsizing cellulose to nanoscale, the surface to volume ratio of NFC increases and the surface hydroxyl groups participate in the formation of hydrogen bonds in the network. Hence, more appropriate mechanical properties for NFC are achieved, even in a lower dosage. Therefore, NFC is theoretically a proper thickener and stabilizer for low-fat systems. Carboxy methyl cellulose (CMC) is a synthesized derivate of cellulose which is gained by adding carboxy methyl groups (- CH2- COOH) to cellulose. CMC is used in different food systems with the E number E466 as emulsions stabilizer, control and modification of texture in various products. In this research, application of combination of nanofiber cellulose (0%-1%) and CMC (0%-1%) to optimize rheological properties and production of low-fat mayonnaise (30% oil) with desirable characteristics were studied. Due to the hydrophilic nature of cellulose derivatives, several research works have been focused on the stabilization of oil-in-water (o/w) emulsions specially salad dressing or low-fat and fat free mayonnaise by NFC. However, no information is available on NFC/CMC mixtures. The main aim of this study was to investigate the possible mutual interactions between NFC and CMC in mayonnaise formulation regarding to the nutritional benefits that each can be individually contribute to low-fat healthy products. Rheological characterization and particle size of low fat mayonnaise, containing NFC and CMC, were conducted to validate the practical applicability of the proposed formulation in food industry.
Materials and methods: The nanofiber cellulose of each formulation (0.25, 0.5, 0.75 and 1%) was first mixed with the related formulation water and pasteurized using a EUROSTAR power control-visc 6000 homogenizer for 5 min inside water bath at 85°C. Then, it was added to the raw materials of its treatment. After production of 5 samples, viscosity test was performed using a rotational viscometer. Then, particle size measurement (D[4,3] with distilled water as the solvent, a Mastersizer 2000 equipped to quartz cell and laser beam with ƛ= 634 nm), light microscopy (optical microscope, magnification of 100×) and rheological tests such as flow behavior (shear rate: 0.01-200 1/s), complex viscosity and frequency sweep (frequency: 0.01-100 Hz) were performed on 3 selected samples (stress-controlled rheometer with a serrated parallel-plate geometry). Commercial low fat mayonnaise (30% fat) produced by Behrouz factory was selected as the control sample.
Results & discussion: Overall, the viscosity results revealed that by the addition of NFC and CMC, only the sample containing 0.5% nanofiber cellulose and 0.5% CMC did not show significant difference compared to the commercial control sample (pG˝) that has revealed the predominating of the elastic features in the mentioned samples, similar to the trend of commercial control sample. The obtained data of complex viscosity was in consistency with this data. With respect to the obtained results of particle size distribution, the sample containing 0.5% nanofiber cellulose and 0.5% CMC were considered to have the minimum value of D[4,3] and desirable uniformity in comparison with other samples.
Conclusion: Considering the aforementioned results, in this study NFC50/CC50 sample containing 0.5% nanofiber cellulose and 0.5% CMC was employed to formulate low-fat mayonnaise with interesting particle size and rheological properties that is attributed to the synergistic interaction between 0.5% NFC and 0.5% CMC. In fact, the effect of fat reduction is balanced by replacing of 0.5% nanofiber cellulose and 0.5% CMC. Therefore, these hydrocolloids generated a robust gel-structure in the network of this sample. In addition, tridimensional gel structure was formed by physical entanglements among polymeric chains along with the development of the crosslinked network formed between both hydrocolloids. On the other hand, reduction of dispersion phase size and suitable uniformity of droplets in NFC50/CC50 sample resulted in appropriate monodispersity, which increases the resistance to deformation and the enhancement of its viscosity.
Amin Rangriz; Seyed Ali Mortazavi; Morteza Khomeiri; Soheil Amiri
Abstract
IntroductionTraditional mayonnaise is probably one of the oldest and most widely used sauces in all over the world. Mayonnaise is a product with particular consistency and is classified as a type of oil in water emulsions. Vegetable oil, acetic acid, and egg yolk are main components of mayonnaise. In ...
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IntroductionTraditional mayonnaise is probably one of the oldest and most widely used sauces in all over the world. Mayonnaise is a product with particular consistency and is classified as a type of oil in water emulsions. Vegetable oil, acetic acid, and egg yolk are main components of mayonnaise. In addition, mayonnaise may contain salt, sweeteners, spices, effective flavor materials, preservatives and stabilizers. It must contain at least 78.5 % of total fat and 6 % pureegg yolk. Due tohigh levels of oil present in mayonnaise, continuous usageof this product may result in diseases such as obesity,arteriosclerosis, hypertension and cardiovascular diseases.Therefore, consumers tend to consume low-fat products.Yoghurt is a very useful fermented milk products in terms of lactic acid bacteria that have beneficial effects on human health and Because of the similarity between this productand mayonnaise in terms of rheological properties, Yoghurt have been selected as a fat mimetic in mayonnaise.Therefore, the objective of present study was to investigate the effects of partial fat substitutionby yoghurt on physicochemical, rheological and sensory properties of low fat mayonnaise.Materials and methodsMayonnaise preparationOne kilogram of each mayonnaise sample was prepared.Different recipes of mayonnaise contained yoghurt asfat mimetic (as % of oil and yoghurt) including (49.5 % & 25%), (33% & 50%), (16.5% & 75%). All formulations contained 13 % Egg yolk, 10 % Vinegar, 1 %Mustard, 1 % common salt ,4 % sugar , sodium benzoate 0.07 % , Xanthan gum 0.2%.Mayonnaise preparation procedure was as follows; firstlyegg and vinegar were mixed together and then all otherIngredients(including Yoghurt for the low fatmayonnaise recipes) except oil were added and mixed well. The oil was finally poured insidethe mixer very slowly and homogenized for 1 min. Subsamples (250 g) of mayonnaise were aseptically transferredto sterile 250 ml, Duran glass bottles withpolypropylenescrew caps and left for one-day at 5 °C.Proximate composition analysisMoisture, protein, and ash contents were determined accordingto AOAC (2005) official methods. Fat content wasmeasured by Bligh and Dyer (1959) method, and totalcarbohydrate content was calculated by difference.Rheological measurementsRheological measurements were performed after 24 hstorage using a Brookfield viscometer Model RVDV-IIwith aspindle no.6 at 5 °C and 25 °C. Shear stress data wereplotted versus shear rate for each mayonnaise sample ata range of spindle speed (10–200 rpm). Plots of Lnshear stress versus Ln shear rate (for each sample) werethen used to calculate values including flow behaviorindex (n) andconsistency coefficient (K).Texture analysisMayonnaise samples were stored in refrigerator for 24 huntil texture analysis. The measurements were carriedout using a Brookfield texture analyzer (BrookfieldLFRA texture analyzer model number 4500 texture prolite) equipped with a 38 mm diameter cylindrical probeat 25 °C.The condition of the analysis was as follows; one cyclewas applied, at a constant crosshead velocity of 1 mm/s to asample depth of 30 mm, and then returned. From the resultingforce-time curve, the values for texture attributes, i.e.firmness, adhesiveness, and consistency were obtained usingtexture pro lit software.pH measurement and stability testpH was determined using AOAC standard method at 25 °C. The samples were assessed for the stabilitytest after 24 h storage at 35 °C. Mayonnaise stability wasdetermined after centrifugation (10 min, 2,500 rpm), andwas expressed as the volume of separated phase to the totalemulsion volume.Color measurementMayonnaise samples were measured for color in the L*, a*,b* system using a Lovibond Colorimeter.Sensory analysisAfter 1 day storage Sensory characteristics including appearance,color, odor, texture, taste, and overall acceptabilitywere evaluated by 14 semi-trained panel on 5-point hedonicscale (1 = the least or the lowest; 5 = the most or thehighest).Statistical analysisAll the tests were performed in triplicate. The data collectedwere analyzed by one-way analysis of variance (ANOVA),and significant differences of means were compared usingDuncan test at 5 % significance level using SAS softwareprogram.Results and Discussion: In present study, physicochemical, texture, sensory and rheological properties were evaluated in mayonnaise formulation with dairy-based. Fat was partially substituted by yoghurt at levels of 25, 50 and 75% which were referred respectively as SM1 (25% fat substitution level), SM2 (50% fat substitution level) and SM3 (75% fat substitution level) and the full fat mayonnaise (S) with 66 % oil was used as control sample. Results indicated that low-fat mayonnaise samples had considerably lower energy content compared with control sample, but higher water content than it. In terms of texture, SM3 had lower hardness compared with control sample. The samples exhibited thixotropic and shear thinning behavior through rheological studies and all samples were classified in the group of solid viscoelastic materials because, in all samples, storage modulus was greater than loss modulus. Also, the loss tangent of low-fat mayonnaise samples were higher than the control sample which reflects the tendency of these samples behavior to pseudo-liquid behavior. Results of sensory evaluation demonstrated that SM2 and SM3samples, were more acceptable. It was concluded that yoghurt can be used as a suitable fat replacer in mayonnaise formulation.
