In 2013, the wooden breast defect in broiler breast meat was characterized by hardened and pale areas at both the caudal and cranial regions of the breast. The objective of this study was to determine the flavor differences between severe woody and normal breast meat in both breast and patties using gas chromatography-mass spectrometry, gas chromatography-olfactometry, and sensory descriptive analysis. Forty-eight individual volatile flavor compounds were identified in both the ground and whole breast chicken samples including aldehydes, ketones, and other functional groups. Minimal differences existed in the volatile fraction of normal and severe woody breast meat. In contrast, woody breast patties had greater concentrations of many oxidation products, including aldehydes, alcohols, and hydrocarbons. The most intense aroma compounds were hexanal, 1-octen-3-ol, 2-pentylfuran, 2-ethylhexyl acetate, and 1-nonanol. The descriptive and volatile results indicated that in patties, woody breast meat was more susceptible to oxidation and off-flavors than normal breast meat.

Pacific bluefin tuna (PBT; Thunnus orientalis) has grown significantly in popularity in recent years due to the globalization of Japanese cuisine. PBT is highly sought after for sushi and sashimi products due to its great quality and taste. Wild populations of this species have been affected by their increasing popularity, pushing innovators in the food industry to create meat alternative versions of PBT. The muscle composition of PBT varies, leading to different types (cuts) of meat in a way that is analogous to various cuts of beef. This study evaluated the differentiation amongst the 6 distinct cuts, including otoro, ventral akami, dorsal akami, ventral chu-toro, dorsal chu-toro, and wakaremi conducting volatile analysis, proximate analysis, and fatty acid analysis. The results from these analyses can then be used as a base standard for companies seeking to create alternatives versions of PBT. Samples analyzed in this study were cultured PBT species that were caught as juveniles and raised in captivity on a PBT farm in Mexico. Volatile analysis was conducted using a SPME GC/MS method. Overall, 41 aroma compounds were identified in PBT that met the identification criteria, including 9 aldehydes, 7 alcohols, 14 alkanes, 2 ketones, 4 alkenes, 3 aromatic compounds, and 2 miscellaneous compounds. Proximate analyses were conducted using standard methods. Significant differences (p <0.05) were found between each cut for the proximate analysis. The fatty acid analysis determined that there were twenty-two identifiable fatty acids found in the different cuts. The omega-3 fatty acids eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) with DHA being present at a higher amount than EPA in each cut. Overall, there are similarities and differences among the different cuts of bluefin tuna that researchers would need to mimic to provide adequate nutritional and sensorial properties of PBT. / Master of Science in Life Sciences / Pacific bluefin tuna (PBT; Thunnus orientalis) is a fish that has gained tremendous popularity over the years due to the globalization of Japanese cuisine. This tuna species is synonymous with high quality and great taste, making it key for sushi and sashimi dishes. The increased demand for this species has caused wild populations to decrease; therefore, the food industry has sought to create meat alternatives for the species. The PBT has 6 distinct cuts that make up the composition of the fish, similar to the differences that can be found in beef cuts. These 6 distinct cuts are otoro, ventral akami, dorsal akami, ventral chu-toro, dorsal chu-toro, and wakaremi. The purpose of this study is to determine the aroma composition, fatty acid composition, and fat, moisture, ash, and protein contents of the different cuts. To measure the aroma composition, gas-chromatography mass spectroscopy (GC-MS) was used; it is a machine that can be used to identify and measure the aroma compounds of products. Standard procedures were used for the other analyses. Overall, 41 aroma compounds were identified in PBT that met the identification criteria, consisting of aldehydes, alcohols, alkanes, ketones, alkenes, aromatic compounds, and some miscellaneous compounds. The cuts displayed distinguishable differences in their fat, ash, moisture, and protein contents. The fatty acid analysis concluded that there were twenty-two identifiable fatty acids found in the different cuts. In this study, close attention was paid to omega-3 fatty acids due to their health benefits for consumers. The omega-3 fatty acids eicosapentaenoic acid (EPA, 20:5n-3) and docosahexaenoic acid (DHA, 22:6n-3) were found in all cuts with DHA being present at a higher amount than EPA in each cut. From this study, researchers have the foundation for understanding the composition of PBT to create a meat alternative that meets consumer expectations.

Peanuts are grown around the world and in United States where most peanuts are consumed after roasting. Peanuts are roasted to a specified color on L*a*b* scale as it is correlated with quality and acceptability. Two batches of Virginia type peanuts were acquired, one normal and other a high oleic variety. A surface response model using the Box-Behnken design was developed for Behmor 2000AB and GeneCafe coffee roasters, for normal and high oleic peanuts respectively with sample size, roast time and power/temperature as dependent variables and L* as a response variable. The model for Behmor was not significant (p>0.05 and R2 =0.87) but with effect contribution of roast time while the GeneCafe model was significant (p<0.05 and R2=0.98) with multiple first and second order effect contributions from temperature and roast time. Each model was validated and Behmor was found to be more consistent and predictable compared to GeneCafe. Both varieties of peanuts were roasted on each roaster and tested for volatile analysis using SPME GC/MS with high variation observed within samples which may be caused by uneven roasting. The volatile results showed similar trends for seventeen compounds between normal and high oleic samples. The Behmor roaster was more effective at predictable roasting for 50 to 100 g sample and more validation is needed on GeneCafe to improve its model. The results can help with quality testing of new varieties of Virginia type peanuts quickly without relying on large sample size typically used in other lab scale studies. / Master of Science in Life Sciences / Peanuts are grown around the world and in United States where most of it is consumed as a confection. They are roasted to a specified color on scale as it is correlated with quality and optimization. We wanted to develop a method of small-scale peanut roasting that allows peanut breeders to roast and evaluate quality of small samples of peanuts. We used an optimization method to test two different coffee roasters for peanut roasting (Behmor and GeneCafe roasters), with normal and high oleic peanuts. Behmor was more sensitive to changes in roast time while GeneCafe was more sensitive to temperature, roast time and combined effects. The models were validated on each machine and Behmor was found to be more consistent and predictable compared to GeneCafe. Peanuts were roasted on each roaster and tested for aroma compounds. The aroma compounds were similar between normal and high oleic samples. The Behmor roaster was more effective at predictable roasting of peanuts with sample size ranging from 50 to 100 g. Our results allow us to predictably roast very small lots of peanuts to support determination of flavor quality for peanut breeding research.