Blackberry (Rubus spp.) is a popular fruit due to its delightful taste and notable health benefits. With a growing demand for regional blackberry production, this study aims to provide Virginia blackberry growers with information on the effectiveness of pre-harvest foliar treatments and shade application on yield, white drupelet disorder, post-harvest attributes, and the aroma profile of two blackberry cultivars, Prime-Ark® Traveler and Prime-Ark® Freedom. The field study was repeated in the 2021 and 2022 growing seasons at the Hampton Roads Agricultural Research and Extension Center in Virginia Beach, VA, in a completely randomized design. Grower standard control (GSC), shade cloth with 30% light reduction (SHA), calcium (CAL), and salicylic acid (SAL) foliar applications were randomly assigned to each variety. Fruit yield and physicochemical attributes of the blackberry were collected and analyzed, and aroma-active compounds in blackberries were identified by use of headspace-solid-phase microextraction-gas chromatography-mass spectrometry-olfaction (HS-SPME-GC-MS-O). Shade cloth significantly reduced the white drupelet disorder (WDD) in Prime-Ark® Freedom but it also reduced the total soluble solid content (°Bx) and °Bx/% titratable acidity (a ratio indicates the sweet and sour balance for fruit) for both cultivars. No significant improvement was found in the TSS, TA, firmness and yield of blackberries treated with CAL and SAL. In total, 16 consistent aroma-active compounds were found across treatments for both varieties and growing seasons. Foliar and shade application did not alter the aroma profile of either blackberry cultivar. However, higher volatile contents were found in 2021 than in 2022, possibly due to climate variation. A clear distinction on aroma profiles of the above two cultivars were also observed: PrimeArk® Freedom was higher in compounds possessing "fruity" and "floral" notes, while PrimeArk® Traveler featured more "green" and "fresh" characteristics. Regional berry growers should be more conservative when adopting foliar and shade applications due to potential seasonal variations surpassing the significance of agronomic treatments. / Master of Science in Life Sciences / Blackberry (Rubus spp.) with its inky purple color, juicy bursts of sweet and tart flavor, and various health benefits has become more popular recently. With growing demands for locally produced blackberries with better flavor, this study will provide Virginia blackberry growers with information on the effectiveness of pre-harvest foliar treatments and shade applications on yield, white drupelet disorder, post-harvest attributes, and aroma profile of two blackberry cultivars, Prime-Ark® Traveler and Prime-Ark® Freedom. The field study was repeated for two growing seasons 2021 and 2022 at the Hampton Roads Agricultural Research and Extension Center in Virginia Beach, VA. All blackberry plants received standard fertigation, with plots receiving additional either calcium or salicylic acid foliar spray, or shade cloth (black mesh cloth) application to reduce 30% direct sunlight. Fruit yield and post-harvest attributes such as sugar content, firmness, phenolic content, and aroma of the Virginia-grown blackberries were studied. Shade cloth (light reduction) was effective in mitigating discoloration in Prime-Ark® Freedom, but it also reduced the sugar content and sweet and sour balance for both varieties. Calcium and salicylic acid were not effective in improving the yield and fruit quality of blackberries. Fruit harvested in 2021 had a more intense aroma and taste when compared to the 2022 season, likely due to the excessive heat and drier climate in year 2. The two cultivars have different aroma profiles, with PrimeArk® Freedom being more "fruity" and "floral" and PrimeArk® Traveler featuring more "green" and "fresh" notes. This study suggests that regional berry growers should be more conservative when adopting agronomic practices such as foliar spray and shade applications due to seasonal variations (temperature, rainfall) possibly surpassing the effectiveness of agronomic treatments.

The unique flavor of high quality Swiss cheese is difficult to reproduce in commercial market cheese. Swiss cheese flavor has never been duplicated or thoroughly understood. New techniques and advances in flavor research have enabled better definition and understanding of food flavors. Therefore, it was desirable to make a detailed investigation of Swiss cheese flavor. Neutral volatile flavor compounds were isolated from Swiss cheese fat by low-temperature low-pressure distillation. The compounds were separated by temperature programmed gas chromatography. Direct analysis of cheese fat and whole cheese from four domestic and two imported good flavored cheeses by gas entrainment and on-column trapping provided a further means of isolation of volatile flavor compounds in Swiss cheese. Gas chromatography in conjunction with rapid scan mass spectrometry and relative retention time data were used to identify compounds. Compounds positively identified by the distillation and on-column trapping techniques were as follows: methanol, ethanol, 1-propanol, 1-butanol, 2-pentanol, trans-2-hexene-1-ol, 2-phenylethanol, acetaldehyde, 2-methyl propanal, 2-methyl butyraldehyde, benzaldehyde, phenylacetaldehyde, acetone, butanone, 2-pentanone, 2-hexanone, 2-heptanone, 2-nonanone, 2-undecanone, 2-tridecanone, 2-pentadecanone, hexane, octane, 1-octene, nonane, 1-nonene, dodecane, pentadecane, toluene, α-pinene, methyl acetate, methyl hexanoate, methyl octanoate, methyl decanoate, ethyl propionate, ethyl butanoate, ethyl hexanoate, ethyl octanoate, ethyl decanoate, ethyl dodecanoate, butyl acetate, 3-methyl butyl acetate, γ-valerolactone, γ-dodecalactone, δ-octalactone, δ-decalactone, δ-dodecalactone, dimethyl sulfide, diacetyl, benzothiazole, o-dichlorobenzene, 1, 2, 4-trichlorobenzene, di-isobutyl adipate, and chloroform. Compounds tentatively identified include an aromatic hydrocarbon, pinane, α-fenchene, ethyl benzene, a di-methyl benzene, methyl benzoate, 2-phenyl-2-methyl butane, 5-methyl-5-ethyl decane, 3-methyl butyl octanoate, 2, 5-dimethyl tetra decane, methyl vinyl ether and 2-methyl propenal. The concentration of selected volatile compounds identified by the on-column trapping technique were determined by relating their peak heights to known quantities of compound. Average concentrations calculated from the mean values for all the six cheeses and expressed in parts per million were as follows: dimethyl sulfide. 0.107; diacetyl, 0.8; acetaldehyde, 1.4; acetone, 1.6; butanone, 0.3; 2-methyl butyraldehyde, 0.42; 2-pentanone, 0.98; 2-heptanone, 0.45; ethanol, 16.3; 2-butanol, 0.3; 1-propanol, 2.9; 1-butanol, 0.7; methyl hexanoate, 1.5; and ethyl butanoate, 0.6. Liquid-liquid partition chromatography and gas chromatography were utilized to determine quantitatively the major free, fatty acids in the six Swiss cheeses. 2-Methyl butyric acid was detected in all cheeses and varied from 9.0 to 100.0 mg/kg cheese. The other isomeric acid, 3-methyl butyric, was detected in only two cheeses. Formic acid was detected in only one cheese. No n-valeric or 2-methyl propionic acids were detected. A synthetic Swiss cheese flavor was prepared utilizing the data obtained in this investigation and that available in the literature for free amino acids. A satisfactory reproduction of Swiss cheese flavor could be achieved only if the mixture contained free fatty acids, volatile constituents, and free amino acids and was adjusted to the pH of natural cheese. / Graduation date: 1966

8 leaves of plates in pocket / Bibliography: leaves 148-154 / 154 leaves : ill ; 30 cm. / Title page, contents and abstract only. The complete thesis in print form is available from the University Library. / Thesis (Ph.D.)--Dept. of Organic Chemistry, University of Adelaide, 1983

Master of Science / Food Science Institute / Edgar Chambers IV / Sorghum (Sorghum bicolor [L.] Moench), is an ancient grain that possesses many health and economic values. Understanding the differences in the flavor profiles among cultivars is essential to increase the usage of the grain for food application purposes. The main objectives of this study were to 1) develop a model system to taste grain varieties and 2) develop a sensory lexicon to describe the flavor profile of sorghum grains. Fifty-seven sorghum cultivars including US commercially available samples as well as important breeding lines from around the world were included and investigated in the study. After thorough investigations, this study developed a model which includes cooked grain and cookie applications to facilitate flavor characterization among different cultivars. The cooked grain and cookie recipes developed in this project are neutral and consistent. Therefore, they can serve as systems prototypes for identification of a grain’s flavor profile and support descriptive analysis studies of flavor among grain cultivars. The developed model has been applied in sorghum and wheat to successfully characterize the flavor profile among different cultivars. Moreover, a sensory lexicon with 28 descriptive terms was developed by the trained panel to describe the flavor of sorghum in grain form and in finished products. Some of the terms in the lexicon were starchy, beany, cardboard, oil-heated, brown-sweet, buttery, umami, overall green, musty dusty, woody, wheat like, sweet, salty, sour, bitter and metallic. Each attribute has a descriptive definition to describe the term and two to three descriptive references. The panel validated the effectiveness of the developed lexicon using a set of 20 sorghum cultivars, which were presented to the panelists in two forms: cookies and cooked grains. The descriptive analysis results were analyzed using PCA to produce sensory maps with key attributes associated with each sample. The generated maps for both cooked grain and cookies application showed clear differentiation in flavors among sorghum cultivars indicating that the lexicon can be used to effectively characterize sorghum’s flavors in multiple applications. Such understanding will help to support researchers, food producers, food manufacturers and contribute to promoting the use of sorghum grains in food applications.

No description available.

Call number: LD2668 .T4 1984 W33 / Master of Science

Call number: LD2668 .T4 1955 B36 / Master of Science

Response Surface Methodology (RSM) was used to study the effect of two variables, sugar level (12-16 °Brix) and acid level (0.3-0.7 % T.A.) on sensory qualities and desirability of blackberry juice drinks. Three blackberry juice levels (10%, 15%, and 20%) were used to study the influence of juice flavor on sensory qualities and desirability of the juice drinks. A trained panel evaluated three attributes, blackberry flavor, sweetness, and sourness intensities, of the juice drinks. The consumer panel gave desirability and three attributes just-right ratings. A Balanced Complete Block Design was used. Blackberry flavor intensity was enhanced by sugar level. Blackberry flavor intensity was enhanced by acid level to a point about 0.5% T.A., and then decreased. Blackberry flavor intensity was not related to °Brix:acid ratio and was only related to the sweetness:sourness ratio at the 20% juice level. Sweetness and sourness intensities increased with increasing sugar and acid levels. There was a suppression effect of sugar and acid on each other in the juice drink. The relationships of sweetness, sourness, and sweetness:sourness ratios to °Brix:acid ratios were all linear. Desirability rating was related to °Brix:acid and sweetness:sourness ratios for the 10% and 20% juice levels, for 15% juice level no association was found. The formula which received the closest to "just right" ratings and highest overall desirability rating had in a °Brix of 15.4 and a % titratable acidity of 0.64, resulting in a °Brix:acid ratio of 24 and a corresponding sweetness:sourness ratio of slightly less than 1.0. In general, the 15% juice level was the best because of its sugar and acid tolerance and high desirability. / Graduation date: 1989

Experiments were conducted to establish whether or not calcium and pectin treatments might improve the typically ragged appearance of canned freestone peaches without impairing other desirable characteristics. and thereby make freestone varieties more acceptable for canning. Accordingly, Elberta peaches were subjected to three types of prepacking treatments, dipping for 30 minutes in 0.00%, 0.05%, 0.10% and 0.50% calcium in the form of calcium lactate and calcium chloride, application of 0%, 1% and 3% low-methoxyl pectin applied as a ten-minute dip and in the syrup along with 0.00% and 0.05% calcium, also as a ten-minute dip, and lastly treatments with 0.00%, 0.02% and 0.03% pectin esterase combined with 0.00%, 0.05%, and 0.10% calcium levels in a 30-minute dip. The peaches were then canned and stored for six months. To determine the effects of the treatments the peaches were evaluated organoleptically for appearance, flavor, and texture and objective measurements of density, soluble solids, shearing strength and sediment in the syrup were made. Although treatments of this nature have proven effective for other fruits and frozen peaches, no outstanding improvement was noted in this project. Pectin esterase at the 0.02% and 0.04% levels, however, did improve appearance slightly and also reduced the amount of sediment in the syrup without impairment of the flavor. Calcium treatment alone did not affect appearance, but did reduce sediment and increase shearing strength although in amounts over 0.05% calcium was detrimental to flavor with calcium chloride being the worst offender. Pectin treatment was actually harmful to both appearance and flavor, probably because of the occurrence of some gellation in several treatments. No differences were noted for texture and although differences in soluble solids and density were observed, they were of small magnitudes. / Graduation date: 1953

Call number: LD2668 .T4 1951 B45 / Master of Science