Master of Science / Department of Food Science / Kadri Koppel / Pomegranate fruits are seasonally produced and require processing to provide year round availability. Effects of processing on phenolic compounds, color, and other physical properties have been examined but few studies have examined the sensory effects. Juice prepared from fresh Wonderful pomegranates was used to prepare fresh frozen juice, batch pasteurized juice, and reconstituted juice from dried arils. These juices were evaluated using analytical and affective sensory methods to increase the understanding of processing effects on pomegranate juice properties. A modified consensus flavor profile showed that a large number of small differences existed. The accumulation of these changes demonstrates the distinction among processing methods. Time intensity multi-evaluation (TIME) profiling, a new method, was used to further understand how multiple attributes, including aromatics, feeling factors, and basic tastes, changed over the course of one sip. Fruity flavor was consistently the first to appear in the profile while bitterness and astringency lasted the longest. The attribute woody displayed longer peak times in the pasteurized and reconstituted samples than seen in fresh frozen juice. Semi-Continuous Consumption (SCC) profiling, another new method, explained product differences over 25 sips that mimicked consumption. Overall, astringent and bitter components increased while fruity and overall sweet attributes declined. These profile changes differed by sample with reconstituted juice showing the least increase in astringency over consumption. The juice samples were subjected to an acceptance test that showed four liking clusters, one that accepted all three juices and three clusters that disliked one of each juice type. The results from these studies are an initial step in describing how processing of pomegranate juice can effect flavor. Understanding the flavor differences is beneficial to processors for marketing products and for purchasers of these products for ingredient usage. Furthermore, the process of TIME and SCC profiling are described which are beneficial for understanding how multiple flavors change over single and multiple consumption events of a product respectively. These new methodologies are useful in explaining the experience of complex products such as teas and coffees or products exhibiting build-up such as nutrition aides.

Master of Science / Food Science Institute / Kadri Koppel / Pomegranate fruits have grown in popularity due to their known beneficial health properties. The objectives of this study were to: 1) determine if flavor differences existed among and within fruits, 2) understand appropriate numbers of replications needed for products that are naturally variable, and 3) compare individual and consensus scores for descriptive sensory analysis over 10 replications of the same product to determine whether differences are found between the methods. Three different sections of the pomegranate fruit were individually evaluated (top, middle and bottom) to determine if flavor differences existed among the fruit sections. Furthermore, the number of repetitions needed in order to obtain small differences in a descriptive panel was calculated. Results showed that pomegranate fruits have natural variation of flavor in the different sections, as well as differences among fruits of the same cultivar. The number of repetitions increased as the differences that wanted to be detected became smaller, and they decreased, as these differences increased. After each sections of fruit were individually evaluated, the panel discussed results and set consensus scores for each attribute. Analysis on mean individual scores and consensus data, along with Principal Component Analysis (PCA) showed that both, individual and consensus methods, provided the same reliable and reproducible information. However, this was evaluated using highly trained panelists. Besides pomegranate juice (PJ), green tea (GT) is one of the most consumed beverages in the world, and has the highest polyphenol content of all teas. Six PJ and GT blends were prepared at different ratios: 90-10, 80-20, 70-30, 60-40, 50-50, 40-60 vol/vol. Lipton GT and Wonderful pomegranates were used to prepare the samples. The objectives of this study were to: 1) determine sensory differences in the samples, 2) consumer acceptance before and after antioxidant information of the samples was provided, and 3) determine their total phenolic content (TPC). Results showed that samples with lower PJ were higher in attributes intensities for Green, and Tea like flavor, while attributes like Berry, Cranberry, Cherry and Sweetness were lower. Consumers liked samples higher in PJ, and sample 40-60 was the least liked. However, overall liking of all samples increased when antioxidant information was given. TPC results showed that pure PJ had the highest content, and as it was mixed with GT, TPC was the sum of the individual percentages of each component. Addition of claims in beverage labels might be a good strategy for consumers to purchase these type of products high in antioxidant content.

The aim of this study was to investigate the effect of high hydrostatic pressure (HHP) treatment (200, 300, 400 MPa / 5

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