The Science of Sensory Evaluation - Assignment Example

Full and section number of Introduction The Science of Sensory Evaluation Sensory evaluation is the science that refers to the measurement and study of evaluation of food and drink items on the basis of their texture, taste, temperature, odor and appearance. Sensory analysis is performed with different purposes. Sensory evaluation would help discover the differences and likenesses between different food items or drinks. Food products are examined, analyzed and rated using the process of sensory evaluation. Food items and drinks are analyzed using sensory evaluation to find out whether any enhancement is required in any of the factors. Sensory evaluation is sometimes done to label a product as acceptable or unacceptable. Sensory evaluation gives information about the typical characteristics of the food product or any of its ingredients so that any necessary change can be made to the food item or any ingredient can be avoided or replaced. A sensory analysis on a final product or newly introduced product would judge whether the food item is in line with its original specification. Feedback is collected after sensory evaluation so that any small or big amendment may be made to improve the product. Further evaluation would include the analysis of the food properties. Properties of the food and its ingredients are scientifically measured. These measured scientific properties are analyzed and interpreted to get the results. Sensory evaluation of food items and newly developed food products Sensory analysis would tell how the assessed food item is perceived through the five senses. Appearance, taste, smell, touch and hearing are the five factors that are used as parameters to analyze the food item. The color of the food item, its smell, its taste, its physical nature and sound would grade it. The color of a food item would reveal some of its properties. For example, deep fried items and those with artificial color would reveal its nature through its color. The smell of gravy will reveal the presence of absence of spices in it. Taste of a food item would disclose majority of its ingredients. Taste would reveal what is included and what is missing. As we touch a cake we will understand how much cream is used for making it. If you want to test a piece of banana or potato chips you just need to bite it once. Sensory evaluation would thus give complete analysis of a food item. Sensory evaluation is very much required for newly developed products. Sensory analysis would check whether a newly developed product is unique or comparable to another product of same range. Some products may be complete imitations of another product which is already established. Some may be having wonderful new properties that make it different from the already established product. When a product is newly developed, sensory quality of the product should be checked and analyzed so that the quality, uniqueness or comparability of the product would be found out. Sensory analysis would give information about the relative acceptability of the product. It would also help to understand the marketability of the product. Goat’s milk yoghurt sensory evaluation – Sample preparation Fresh goat’s milk is collected from a goat farm and yoghurt is prepared using different research experiments. The newly developed goat’s milk yoghurt is compared to cow’s milk yoghurt using descriptive analysis tests, flavor profile analysis test and texture profile analysis. Sample of the newly developed goat’s milk yoghurt and sample of cow’s milk yoghurt is taken and provided for analysis. The team of panelists compared the different characteristics of both varieties of yoghurt. Texture, taste, color, aroma, creaminess, thickness, and other sensory characteristics are analyzed for both varieties of yoghurt. Sensory evaluation by panelists using different tests This test supplied comprehensive information about the perceptible aroma and flavor details (flavor components) of goat’s milk yoghurt. A comparative analysis is done on cow’s milk yoghurt and goat’s milk yoghurt using sensory analysis. Flavor notes and aroma notes are provided and compared for both types of yoghurt. The intensity of each taste is measured in the analysis process. A panel of two members examined the product using different criteria. Both the panelists independently analyzed the product and gave descriptive notes about the flavor and aroma of the product. The flavor profile gave information that can be presented in a descriptive report. The flavor profile doesn’t require statistical analysis. Further detailed data report is not considered as the product under study is not of multiple ingredients. Further, goat’s milk yoghurt being the natural product with no other special ingredient packaging details, processing details and other similar product related data are not analyzed. The report or the following information is derived from the interaction made by the panelists. The judgment of the panelists gave the comparative information between the two varieties of yoghurt. Apart from flavor profile analysis, texture profile analysis (Sensory Evaluation Division of the Institute of Food Technologists, 1981) is performed though the sensory evaluation process. Texture profile analysis is also done through description data and the result information is provided as descriptive information. Using the principles of flavor profile method a descriptive texture profile analysis is performed. Comparison of sensory characteristics of goat’s milk yoghurt and cow’s milk yoghurt Comparisons of goat’s milk yoghurt to cow’s milk yoghurt, done through sensory evaluation reveal the differences between the two. The criteria of analysis used in sensory evaluation determine to what extent goat’s milk yoghurt is comparable to cow’s milk yoghurt. The analysis questions of sensory evaluation describe the characteristics of the food product. These questions further give the result that would tell if there is real difference between the products. Analysis would also measure the degree of difference between the products. Flavor, thickness, fat presence, creaminess, aftertaste, texture and few other characteristics of goat’s milk yoghurt is compared to that of cow’s milk yoghurt. Yoghurt prepared from goat’s milk is evaluated for its sensory characteristics. The sensory properties of goat’s milk yoghurt are further compared to the respective characteristics of cow’s milk yoghurt. The sensory factors considered for review include the characteristics goaty, salty, creamy, sour, sweet, throat burn, pungent and astringent. Sensory evaluation study revealed that the sensory attributes of cow’s milk yoghurt is comparatively less intense than that of goat’s milk yoghurt. Cow’s milk yoghurt is found to be having low levels of salty, sweet and other flavors. Cow’s milk yoghurt also do not have intense milk taste unlike goat’s milk yoghurt that has a typical flavor that makes people recognize it. The astringent pungent flavor is absent in cow’s milk and cow’s milk yoghurt. Goat’s milk yoghurt has intense flavors compared to cow’s milk yoghurt. These intense flavors often make goat’s milk yoghurt less preferable than cow’s milk yoghurt. This is the reason why fruit pieces and other essences are added to goat’s milk yoghurt so that the typical goaty and pungent flavors disappear. Flavor attributes are weak for cow’s milk yoghurt while comparing with goat’s milk yoghurt. Goat’s milk yoghurt is sometimes mixed with cow’s milk yoghurt to make a balance of the taste attributes. Goat’s milk yoghurt has a soft texture compared to cow’s milk yoghurt. Goat’s milk yoghurt has a creamy appearance that makes it different from cow’s milk yoghurt (C, Uysal-Pala et al, 2006). Cow’s milk yoghurt has an uneven texture with fat particles separated and separated to the top layer of the yoghurt. High amount of fat particles makes it thicker but uneven and less creamy (C, Uysal-Pala et al, 2006). Goat’s milk yoghurt is however made of small fat particles that do not rise to the top. This makes a big difference between the texture of cow’s milk yoghurt and goat’s milk yoghurt. Having small fat globules that remain suspended, goat’s milk yoghurt is soft, thin and easily digestible (Chye, S. J. et al 2012). Goat’s milk yoghurt remains creamy with even fat particles and cream unlike cow’s milk. The corresponding difference is present in yoghurt version of goat’s milk and cow’s milk. In cow’s milk and cow’s milk yoghurt fat particles would rise to the top and stay there. Fat modules are not evenly distributed in cow’s milk and cow’s milk yoghurt. In goat’s milk and yoghurt however, fat particles would remain suspended, not rising to the top. Because of this even distribution of fat modules, goat milk and goat milk yoghurt has a natural homogenization. This would also give it a creamy nature. Casein found in cow’s milk and that in goat’s milk is different. As goat milk contain low amounts of fat, protein and lactose, yoghurt made from goat’s milk is lighter and softer compared to the yoghurt made from cow’s milk. Being more alkaline, goat’s milk and goat’s milk yoghurt is whiter and thinner than cow’s milk and cow’s milk yoghurt. Curd prepared from goat’s milk is not thick or firm like that prepared from cow’s milk. The reduced presence of fat modules makes the difference. Cow’s milk yoghurt is naturally thicker than goat’s milk yoghurt. Goat’s milk yoghurt is creamy but not thick. Goat’s milk when converted to yoghurt would give a creamy curd. It will not form lumps or clots like cow’s milk yoghurt. The reduced level of lactose and fat makes goat’s milk yoghurt easily digestible than cow’s milk yoghurt. The allergen lactose makes cow’s milk yoghurt unbearable for people with lactose intolerance. Goat’s milk curd is found to be having a natural sweet and salt taste unlike cow’s milk curd that is plain and needs either sugar or salt for a good flavor. The natural sweetness of goat’s milk yoghurt makes it tasty without adding sugar or salt. Further the creamy nature of goat’s milk yoghurt makes it better than cow’s milk yoghurt which is mostly constituted of lumps. Separation of curd and whey is more evident in cow’s milk curd compared to goat’s milk yoghurt. Flavor profile analysis gives the flavor differences between cow’s milk yoghurt and goat’s milk yoghurt. Cow’s milk yoghurt has the popular sour taste with no sweetness or pungent taste. Cow’s milk does not have any typical flavor unlike goat’s milk which is blamed to be having a typical ‘goaty’ flavor. The pungent or goaty flavor was not considered severe or undesirable by the members of the sensory analysis panel. Goat’s milk yoghurt has a tangy, light sweet taste which is different from the taste of cow’s milk yoghurt. Goat’s milk taste is sometimes identified as a pungent taste unlike cow’s milk. It is slightly sweet with a different flavor. The comparison of color of the two types of yoghurt is also done through sensory analysis. According to the results given by the panelists, goat milk yoghurt is whiter in appearance compared to cow’s milk yoghurt. Cow’s milk yoghurt turns yellowish as hours pass. This is because of the heavy presence of fat in cow’s milk yoghurt. Goat’s milk yoghurt remains whiter because of the absence of heavy fat particles in it. Conclusion Yoghurt made from cow’s milk yoghurt is compared to yoghurt made from cow’s milk yoghurt using sensory evaluation tests. The textures, thickness, creaminess, color, taste and aroma of goat’s milk yoghurt is compared to that of cow’s milk yoghurt. Sensory analysis tests are used for evaluating the sensory properties of goat’s milk yoghurt. Flavor profile analysis and texture profile analysis is performed on goat’s milk yoghurt and it is compared to the corresponding parameters of cow’s milk. A panel of sensory evaluation specialists performed the sensory analysis and gave the sensory evaluation report of goat’s milk yoghurt. Cow’s milk yoghurt is found to be thicker and fattier compared to goat’s milk yoghurt. Goat’s milk yoghurt is less fatty but creamy compared to cow’s milk yoghurt. The texture of cow’s milk yoghurt is different from that of cow’s milk yoghurt. Cow’s milk yoghurt has an uneven texture while goat’s milk yoghurt has a creamy even texture. Goat’s milk yoghurt has a typical goaty flavor with light sweetness or salty taste. Cow’s milk yoghurt however does not have this typical taste. Cow’s milk yoghurt has a plain taste with curd and whey separated and fat particles floating at the top. References Abdel Moneim E, S,, Rania M, A, Zakaria A, S (2011) Effects of Storage on Quality of Yoghurt Prepared from Cows and Goat’s Milk and Pure Strains of Lactic Acid Bacteria, J.Sc. Tech. Chye, S. J., Ahmad, R. Noor Aziah, A. A. (2012) Studies on the physicochemical and sensory characteristics of goat’s milk dadih incorporated with tropical- fruit purees, International Food Research Journal 19(4). C, Uysal-Pala, Y, Karagul-Yuceer, A, Pala and T, Savas, (2006) Sensory properties of drinkable yogurt made from milk of different goat breeds. Sensory Evaluation Division of the Institute of Food Technologists (1981), Sensory Evaluation Guide for Testing Food and Beverage Products, Food Technology. Read More