Master of Science, The Ohio State University, 2014, Food Science and Technology
Tomatoes are the second most important crop after potatoes around the world and most of them are consumed as processed tomatoes such as tomato paste, tomato sauce and ketchup. Several quality parameters need to be controlled during processing in order to ensure the desirable quality of the final product. Some of the most commonly used quality traits in tomato industry are pH, °Brix, Bostwick consistency, predicted paste Bostwick, Ostwald value, serum viscosity, color, reducing sugar and organic acids content. One alternative that has been studied to provide rapid and reliable analysis of quality traits in tomato products is infrared (FT-IR) spectroscopy which has shown good prediction of the soluble solids, titratable acidity, pH, reducing sugars, organic acids and carotenoids content in different tomato products with little sample preparation; however, rheological properties had not been predicted using this novel technology. Previous studies for determination of quality traits in tomato products using FT-IR spectroscopy have required some sample preparation, such as filtration and centrifugation, which reduces the rapidness of the methodology and increases the cost of the analysis since filters and syringes are required. Therefore, our objective was to develop a rapid and reliable method using a portable FT-IR spectrometer for the determination of important quality traits in tomato juice, including rheological characteristics, using direct measurements on the tomato juice. Tomato juice samples (n=180) from varieties and breeding lines encompassing a wide range of quality characteristics were obtained from California. At the time the juice was produced, serum viscosity (Ostwald), consistency (Bostwick), pH and °Brix (refractive index), were measured. Juice samples were shipped to The Ohio State University where spectra were collected in duplicate using a portable FT-IR in the transmittance mode (50µm) and reducing sugars (glucose, fructose) concentrations were dete (open full item for complete abstract)
Committee: Luis Rodriguez-Saona Dr. (Advisor); Lynn Knipe Dr. (Committee Member); Monica Giusti Dr. (Committee Member)
Subjects: Food Science