Document Type : Research Article

Authors

• Azam Ayoubi ¹
• Mahda Porabolghasem ²

¹ Department of Food Science and Technology, Faculty of Agriculture, Shahid Bahonar University of Kerman, Kerman, Iran.

² Department of Mechanical Engineering of Biosystem, Shahid Bahonar University of Kerman,Kerman, Iran.

Abstract

Introduction: Increased intake of calorie and decreasing physical activity might increase the risks for cancer, obesity, cardiovascular diseases, diabetes mellitus and hypertension. Using natural sweeteners instead of sugar in food formulations can be a good method to reduce the calorie intake. World Health Organization recommends limiting added sugar intake to <10% of total energy. Many sugar substitutes were used in food products such as glucose syrup, molasses, fructose syrup, invert syrup and malt extract. Utilization of fruits in food preparation while requiring sweet taste is a wise strategy to reduce the added sugar intake. Dates are ideal fruits to substitute added sugar in foods, and they play an important role in daily nutrition of many people in the arid regions. Date fruits are rich in dietary fiber, phenolic compounds, minerals, vitamins, antioxidant and antimutagenic compounds. Date syrup that produces from date is one of the suitable replacements that can be used for substituting sugar. Date syrup is a high energy food rich in carbohydrate, a good source of minerals; but it is also contains a very complex mixture amino and organic acids, polyphenols and carotenoids. Date syrup contains fructose, glucose and small amount of sucrose. Low quality date cultivation occupies about 60% of the total plantation. These dates are poor in size and taste, unsuitable for consumption. The presence of high sugar content in these low quality varieties makes them suitable for producing date syrup. The purpose of this research was study the effects of substituting sugar with date syrup on physicochemical and sensory properties of cupcake.
 
Materials and methods: Date syrup purchase from Dambaz Company and wheat flour purchase from Tavakkol factory of Kerman.  Other materials purchased from local market of Kerman. In this research four different level of date syrup (25, 50, 75 and 100%) were used in cake formulations as a sugar substitution and the effects of dates syrup on the physicochemical (including weight loss, pH, porosity, density, moisture, hardness of texture and color of crust and crump) and sensory (texture, crust color, taste and total acceptance) properties of cupcake were studied. The weight loss calculated by measuring difference of weight before and after baking. pH was measured by a digital pH meter. cake moisture content was determined by drying samples at 130±2°C in a hot air oven. The volumes of the cake samples were measured by the seed displacement method and then density was calculated by dividing the volume by the weight. For evaluation of porosity used Image j method. Hardness of the cake samples were measured with Instron testing machine. Color measurements were done using a Hunterlab Colorimeter. Analysis of variance (ANOVA) was conducted for data using MSTAT-C software. Differences among the mean values were also determined using Duncan’s Multiple Range test. A significant level was defined as a probability of 0.05.
 
Results & Discussion: Data analysis showed that the date syrup, significantly affected the physiochemical and sensory properties of the cake. It was discovered that by increasing the percentage of date syrup in cake formulation, weight loss decreased and moisture increased. Sugars make hydrogen bonds with water molecules due to their hydroxyl groups, because of the molecular structure of the sugars like sucrose, fructose and glucose, it seems that increasing functional groups in date syrup sugars compared with sucrose, resulted in the formation of more hydrogen bonds, which caused the reduction in the mobility of free water and therefore make an increase in moisture of cake. According to the results, pH and porosity of the cake decreased as the date syrup level increased. The results showed that increasing date syrup level caused an increase in density. By decreasing the volume of cake density increased. The volume probability decreased because of affecting reduced sugars and changing viscosity and density of the cake batter. Based on the results, hardness increased significantly with increasing replacement of sugar with date syrup. The possible reason for this result was due to decreasing volume and porosity of cake with increasing date syrup content. The color of the cake is due to the Maillard and caramelization reactions during baking. A key element in Maillard reaction is reducing sugar which is abundant in date syrup and able to enhance the brown color. The results showed that the crust and crump lightness (L) decreased significantly with increasing the levels of date syrup. The crust and crump yellowness (b) were significantly less than control. With reducing sucrose level, the redness of the crust and crump increased significantly. According to sensory evaluation results, scores of crust color, texture and total acceptance of the cake remained unchanged when up To 50% date syrup was used. However, further addition of date syrup significantly reduced these scores. The results showed that the cake formulation with 100% date syrup date obtained the lowest score by panelists in terms of taste. Least value of weight loss (19/2%), porosity (19/5%) and most value of density (0/5 g/cm³), darkness of crust (32/47) and crump of cake (35/64) were related to substitution level of 100%. Present study demonstrated that the date syrup could replace up to 50% of the sugar without affecting the quality of cupcakes.

Keywords

• Color
• Cupcake
• Date syrup
• Hardness
• porosity