Master of Science / Department of Food, Nutrition, Dietetics and Health / Edgar Chambers IV / Smoking of food is one of the oldest methods of food preservation and still is used widely to help preserve foods such as meats, fish and cheeses. Apart from its conservation function, the smoking process also has a considerable influence on the sensory characteristics of the products. A highly trained, skilled descriptive sensory panel identified, defined and referenced 14 attributes related to the flavor of food products labeled as smoked or smoky. The lexicon included: Smoky (Overall), Ashy, Woody, Musty/Dusty, Musty/Earthy, Burnt, Acrid, Pungent, Petroleum-Like, Creosote/Tar, Cedar, Bitter, Metallic and Sour. Definitions of these attributes were written and references were found that anchor a 0-15 point scale. This lexicon was used to evaluate the differences among smoked products under different circumstances such as products on the market versus products smoked at home, different woods used to smoke products and the length of time a product spends in the smoker. There are many methods used to impart this smoky flavor and due to health, environmental and economic concerns, many producers use nontraditional methods while hobbyists thrive on the traditional methods. Descriptive analysis was used to see if there are differences between products smoked using an at-home smoker and market products. Using principal component analysis, cluster analysis and analysis of variance, it was found that market products were significantly different than products smoked using an at home smoker. The market products were significantly more Sour and less Smoky, Ashy, Woody, Musty/Dusty and Acrid. Many types of woods are used to smoke products and many market products distinguish themselves based on the wood used. Six highly trained panelists evaluated pork that was smoked with either hickory, mesquite, cherrywood or Applewood and was smoked for 1, 2 or 4 hours. The flavor profiles of the smoke flavor was similar between the types of woods although as the length of time in the smoker increased and the intensities of most attributes rose, the differences among products smoked with different woods became more pronounced. Apple wood smoked products had higher intensities for Overall Smoky, Ashy, Burnt, Pungent, Petroleum-Like, Creosote/Tar and Cedar, while cherry wood smoked products had lower intensities for all attributes. Hickory and Mesquite smoked products were not significantly different from each other and typically scored between the other two woods. Smoking is a slow process and many popular restaurants that smoke their own products find that their claims of smoking for long periods of time are beneficial to their image. Descriptive analysis was used to see how the flavor changes based on the length of time the product (pork) was in the smoker. The samples of pork ranged from not smoked to smoked for 15 hours, with samples at every 2.5 hour increment. For most attributes, the intensities went up with the amount of time the product was in the smoker. The only exceptions were Musty/Earthy and Sour. The regression analysis revealed that Smoky, Ashy, Acrid, Creosote/Tar and Bitter are all at least moderately correlated with the time the product spent in the smoker.

Human assessors are currently the best instruments for evaluating the sensory properties of both food and non-food consumer products. In the early stages of descriptive sensory panel training, a lexicon is still undergoing refinement and assessors are only beginning to understand the identities of sensory attributes and how to use the scale to communicate the intensity of sensations. To expedite training, the panel leader provides structure and feedback. Several statistical approaches have been proposed that indicate training status. In this thesis several approaches are reviewed, and a multistage process that involves scrubbing data, estimating parameters, reviewing fit, and exploring multivariate relationships is developed. The process reveals attribute misunderstandings, considers candidate training targets for subsequent training sessions, and explores data to better understand product properties.

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Master of Science / Food Science Institute - Human Nutrition / Kadri Koppel / Pecan [Carya illinoinensis(Wangenh.) K. Koch] is a native North American nut tree that has progressed into a significant agricultural crop. Flavor characteristics were evaluated for sixteen pecan cultivars: ‘Giles’, ‘Hirschi’, ‘Maramec’, ‘Oswego’, ‘Lakota’, ‘Chetopa’, ‘Colby’, ‘Witte’, ‘Dooley’, ‘Kanza’, ‘Pawnee’, ‘Stuart’, ‘Chickasaw’, ‘Peruque’, ‘Major’, and ‘Henning’ using descriptive sensory analysis. A trained panel consisting of six panelists first developed a vocabulary for the raw pecans and scored the intensities of the samples for 20 flavor attributes. Results showed that the sixteen samples differed significantly (P ≤ 0.05) on 10 of the attributes. ‘Giles’, ‘Lakota’, and ‘Pawnee’ differed from the other 13 cultivars for the majority of the attributes. The remaining thirteen cultivars showed few differences in individual attribute ratings, but did show differences when mapped using multivariate techniques indicating as many as two clusters of pecan cultivars based on flavor. The same sixteen cultivars were then roasted and evaluated using descriptive sensory analysis by the same trained panel using the same 20 flavor attributes. Three texture attributes were also evaluated. These results were compared to the results from the raw pecans. Results showed that 4 attributes differed significantly across all cultivars when raw and roasted flavor was compared. Ten of the flavor attributes had higher intensities for the roasted pecans than for the raw pecans. Most of these attributes fell within the categories of ‘nutty’ and ‘sweet’. When pecans were roasted many flavor attributes were intensified, as compared to when they were raw. How the flavor of the sixteen cultivars changed over a 12 month period was then evaluated. Raw pecans were evaluated when fresh, at 3 months, 6 months, 9 months, and 12 months by descriptive sensory analysis. A trained six member panel evaluated four flavor attributes at all five time points. Results showed that bitter had the highest intensity scores for all 16 cultivars at all 5 time points. Rancidity increased over time and sweetness decreased over time for all attributes. The results from these studies can be used as a baseline for future pecan research.

Master of Science / Food Science Institute -- Human Nutrition / Delores H. Chambers / This research aimed to determine the sensory characteristics of commercially-available plain yogurts and examine how three "more sustainable" prototypes compared. Three experimental non-fat set-style yogurts were provided – one control and two samples that differed in fermentation time. These shortened fermentation times could result in energy reductions and potentially substantiate a “sustainable” marketing claim, a concept gaining traction with consumers. Twenty-six commercially-available yogurts varying in percent milk fat, milk type (organic or conventional), and processing (set-style, stirred, or strained/Greek-style) were also included. Using descriptive sensory analysis, a six-person highly-trained panel scored the intensity of 25 flavor, six texture, four mouth feel, and two mouth coating attributes on a 15-point numerical scale. Three replications were conducted, and all samples were tested at least 10 days prior to the end of their shelf-lives. The samples differed for 19 flavor and all texture, mouth feel, and mouth coating attributes. Cluster analysis indicated approximately seven flavor and five texture (texture, mouth feel, and mouth coating combined) clusters, resulting in 15 unique combinations of flavor and texture. Although no legal definitions exist for “sustainable,” the prototypes’ sensory characteristics were comparable to those of top-selling yogurts indicating potential market viability. This research also demonstrated potential growth opportunities. Despite the current diversity, several combinations of flavor and texture were not represented.

Master of Science / Food Science - Human Nutrition / Delores Chambers / Researchers evaluated the flavor characteristics of seven black walnut (Juglans nigra L.) cultivars: Brown Nugget, Davidson, Emma K, Football, Sparks 127, Sparrow, and Tomboy using descriptive sensory analysis. Seven trained panelists developed a lexicon for the black walnuts and scored the intensities of the samples for 22 flavor and taste attributes. Results showed that the 7 samples differed significantly (P ≤ 0.05) on 13 of the attributes. For the majority of the attributes, only Emma K differed from the rest of the cultivars by being characterized with lower scores for black walnut ID, overall nutty, nutty-grain-like, nutty-buttery, floral/fruity, oily, and overall sweet. It also was higher in acrid, burnt, fruity-dark, musty/earthy, rancid, and bitter attributes. Researchers then incorporated the black walnut cultivars into a simple cookie recipe and evaluated the samples for differences in flavor attributes using the same trained panelists. Nine of the 25 attributes differed significantly across cultivars: black walnut ID, overall nutty, nutty-buttery, brown, toasted, acrid, rancid, overall sweet, and sweet (P ≤ 0.05). Lower mean scores in black walnut ID, overall nutty, and sweet and higher mean scores in rancid and acrid characterized the Emma K cookie. A PCA biplot revealed that cookies with Football, Sparks 127, and Sparrow walnuts related with one another and the attributes nutty-woody, leavening, and piney. A consumer acceptance test for six of the cookies (Tomboy cultivar was excluded) was also performed. There were four significant clusters of consumers that differed in their acceptance of the cookie samples. Cluster 1 preferred Football, clusters 2 and 3 each showed no overall preference, and cluster 4 preferred Emma K suggesting a set of niche consumers for black walnut cookies. Results presented in this paper can assist black walnut growers in determining which cultivars to plant and harvest. By knowing which cultivars have the most desirable flavor characteristics, growers can focus time and resources on select cultivars, therefore resulting in higher quality black walnuts as products to be sold to consumers in various formats. By consciously choosing which cultivars to harvest, black walnut growers can meet market demand and increase profit.

Master of Science / Department of Food Science / Edgar Chambers IV / Sparkling wines represent an important part of the full wine category. Currently, no lexicon exists that includes aroma, flavors, and mouthfeel for sparkling wine. The objectives of this research were to:1) develop an aroma, flavor, taste and mouthfeel lexicon for sparkling wines, 2) train a panel to use this lexicon on white sparkling wines, which represent the majority of sparkling wines, and validate the panel’s performance with white sparkling wines. For lexicon development, 25 sparkling wines were selected from 132 by a team of sensory professionals and winemakers. The lexicon developed included 13 mouthfeel and taste, 48 aroma, and 48 flavor (aromatic) attributes (109 total attributes). For lexicon training, 22 experienced wine panelists participated in 10, 3-hour sessions over two weeks. After training was complete, panel performance was validated with a practice phase and two studies. Analysis of panel discrimination (i.e. sample p-value) and within panel reproducibility (i.e. correlation of panelist with panel intensity) indicated that the new lexicon differentiated sparkling wines consistently. Further, principal components analysis for studies two and three revealed grouping by wine type (e.g. brut, extra dry, etc.) again validating the new lexicon.

Doctor of Philosophy / Department of Food, Nutrition, Dietetics, and Health / Kadri Koppel / The pet food industry represents a competitive and growing part of the food industry that is constantly looking for innovation to differentiate products in the market. In recent years, the pet food market has undergone a humanization trend that has transformed pet owners into parents. In the light of this trend, pet owner acceptance has become even more crucial to product developers as the owners are the ones who make purchasing decisions. Performing descriptive sensory analysis on pet foods utilizing a human panel can assist in understanding the sensory characteristic of products. Knowing the sensory profile of pet food can then be useful in product development, in order to relate the descriptive data with palatability data from pets and to understand specific sensory attributes that drive pet liking. At the same time descriptive analysis can help understand what drives consumer acceptance of the products. The first objective of the research was to develop a sensory lexicon that could assist researchers and sensory professionals working in the pet food industry to describe appearance, aroma, flavor, and texture characteristics of dry dog food. More than seventy sensory terms were identified, defined, and referenced. The second objective was to utilize this sensory lexicon to understand relationships between sensory properties of products and pet owners’ liking. Results indicated that appearance played a major role in driving consumer liking of dry pet food. The next objective of the research was to understand sensory qualities and acceptance of extruded dry dog food manufactured with different fractions of red sorghum through some of the developed concepts. Sorghum is an important crop to Kansas that represents the first producer in USA. Sorghum characteristics such as a low glycemic index and antioxidant properties make it a perfect fit for pet food industry. A process such as extrusion may then help improve some negative characteristics such a lower digestibility that has been associated with sorghum in the past. Descriptive sensory analysis was performed and results indicated that aroma and flavor profile of the sorghum diets were not dissimilar to the ones of a control diet manufactured with rice, wheat, and corn, grains that are typically used by the pet food industry. Acceptance of pet owners was then assessed through a Central Location Test involving 105 consumers. The whole sorghum diet resulted to be the most liked sample by consumers, at the same level of the control diet. The next objective was then to understand how the experimental diets would be accepted by pets compared in a home situation. Thirty dogs were fed the diets in their own household environment over 20 consecutive days. No differences in acceptance for the diets were found. The last portion of the research was to determine volatile compounds present in the four diets and try to identify possible relationship with the sensory properties of the samples. Thirty-six compounds were identified with aldehydes being the most abundant volatiles group. Several relationships with sensory characteristics of samples were found.

Master of Science / Department of Human Nutrition / Kadri Koppel / Palatability of pet food is an important factor influencing food purchase decision of pet owners. In industry, single- or two-bowl methods are traditionally used to determine food acceptance or preference by pets but shortcomings exist to these methods. The first objective of this study was to propose and develop a preference ranking procedure. Preliminary testing consisted of five phases each lasting five days. Each day twelve beagles were presented 5 treats encased in identical rubber toys (“kongs”). The order of selection was considered as the ranking of preference. The five phases consisted of training, testing lab-baked treats formulations with five varieties of fats, starches and proteins, and commercial foods. The dogs generally ranked 1-2 flavors above others, indicating this procedure could be a more efficient method to determine preference since more samples can be evaluated simultaneously. The second objective was to validate this procedure by following the same process as the preliminary test. The results from phases 2 to 4 showed a similar pattern. For phase 5, various treat formulations were tested by combining the most to least preferred ingredients in each category. The results proved that the ranking of the formulations resembled the preference of the dogs for individual ingredients. Therefore, this procedure was concluded to be reliable. The third objective was to use descriptive sensory analysis to study the sensory characteristics of the treats and gain insights on the drivers of dogs’ preference. Five highly trained panelists profiled the aroma of the treats and the data was analyzed with the preference results collected from the dogs. The external preference maps showed that fish and meaty aromatics tended to be liked by the dogs and grain and musty/dusty aromatics appeared to be disliked. The last objective of this study was to further explore the applications of this procedure by studying the effect of toy/puzzle toy of the treat and ingredient dosage/ratio. With the same dogs, Styrofoam cups (puzzle toy alternative) and kongs were evaluated separately with the same treats. The results collected with Styrofoam cups were similar but less discriminating than kongs. It potentially suggested that the difficulty level of the toy can affect the significance of the dogs’ preferences. No significant preference was observed when testing the treats with different ratio of the most and the least preferred protein sources, although the human descriptive panel was able to provide different profiles for the samples. In conclusion, the preference ranking procedure is a reliable test method but more research is necessary to further explore applications.

The US cider market has expanded in recent years, but limited research-based information is available on fermentation management. This study investigates how apple cultivar and yeast inoculation affect the chemical and sensory properties of cider. Four ciders were produced in triplicate using combinations of two different apple cultivars - Harrison, a cider cultivar and GoldRush, a dessert cultivar - and two fermentation strategies - inoculated with dry active yeast EC1118 or Pied de Cuvé ambient fermentation. Ciders were analyzed for alcohol content, free/total SO2, titratable acidity, volatile acidity, malic acid, pH, and residual sugar. Sensory evaluation was conducted using Descriptive Analysis with trained panelists. Results were analyzed via ANOVA and Principal Component Analysis. Apple cultivar and fermentation method resulted in significant differences for chemistry and sensory parameters. Malic acid concentration was greater in the control ciders while concentrations of both residual sugar and volatile acidity were higher in the PDC ciders. The interactions effect of cultivar*fermentation method influenced both malic acid and residual sugar concentrations, where concentration differences between control and ambient ciders is smaller for GoldRush than for Harrison, showing that fermentation style produces different results across cultivars. Volatile acidity produced opposite interaction effects as differences between fermentation styles was larger for GoldRush. For sensory attributes, Harrison ciders produced high intensities for multiple attributes, but also higher variability. Multiple sensory descriptors displayed interaction effects as the fermentation method produced different results in different cultivars. This study demonstrates that increasingly popular practices in the industry can produce significantly different ciders. / Master of Science in Life Sciences / The US cider market has grown rapidly in recent years, with many new products entering the market. However, there is limited research-based information available on cider fermentation management. This study investigates how production variables, namely apple cultivar and yeast inoculation, affect the chemical and sensory properties of the cider created. The overall goal of this project is to assess the chemical and sensory characteristics that come from cider production treatments. In this study, four experimental ciders were produced using combinations of two different apple cultivars – Harrison, a cider cultivar and GoldRush, a dessert/fresh market cultivar – and two fermentation management strategies – inoculated with dry active yeast strain EC1118 or indirect inoculation through a natural fermentation method. Ciders were analyzed for alcohol content, free and total SO2, titratable acidity, volatile acidity, malic acid, pH and residual sugar. Sensory evaluation was conducted by a trained panel providing descriptive terms and intensities for each sample. Both chemical and sensory results were analyzed to reveal significant differences in samples based on not only apple type and inoculation method, but also the interactions between those two variables. This study demonstrates that increasingly popular practices in the cider industry – like natural fermentation or the use of cider-apple varieties – can produce significantly different ciders. This highlights the idea that producers need to treat each apple cultivar differently, as they behave differently throughout production.