Pediococcus cerevisiae, Lactobacillus casei, Lactobacillus plantarum,
Leuconostoc mesenteroides, Lactococcus diacetylactis Bifidobacterium
bifidum, Leuconostoc oenos, and mixed cultures of Propionibacterium
shermanii and P. cerevisiae were used to ferment cucumber juice brine
(CJB) at 22-26°C for 1.5 months. Sugar utilization ranged from 14.6 to 86.1%.
pH of the fermented CJB ranged from 3.24 to 4.12 and titratable acidity ranged
from 0.30 to 0.93%. All strains tested degraded malic acid and citric acid. Leu.
mesenteroides and Leu. oenos did not utilize citric acid for diacetyl-acetoin
production. The concentration of acetic, propionic and lactic acids varied
among the fermentation treatments. The heterofermenters produced high
concentrations of CO₂, ethanol and mannitol and CJB with high
volatile/nonvolatile acid ratios. The fermentation balance indicated that
sugars had been used to produce compounds not measured in this study.
Twelve aroma and six flavor by mouth descriptors were used to
describe flavor of the final products in the trained panel descriptive
analysis. Sourness intensity was the only sensory descriptor that correlated
with the chemical analysis data. The intensities of seven aroma and three
flavor by mouth descriptors were significantly different (p < 0.05) among
treatments. Aroma preference mean scores from 9-point hedonic scale
ranged from 4.69-5.39; they were not significantly different (p > 0.05).
Formation and Potential Industrial Applications of An Insoluble
Polyelectrolyte Complex: Chitosan-Polyacrylic Acid
Chitosan and polyacrylic acid mixtures were prepared in different
mole ratios and at different ionic strengths (0.025-0.300). No insoluble
complex formation at pH=2 was detected. In the 3 to 6 pH range, the maximum
complex formation occurred at different mole ratios. The complex
composition is affected by pH but not by ionic strength. An electrostatic
interaction between -COO⁻ and -NH₃+ groups was involved in complex
formation. This study suggests that process recommendations for industrial
application of chitosan as a coagulating agent can be made based on the ionic
strength, pH and charge group concentration of the fluid to be treated. / Graduation date: 1990
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/27283 |
| Date | 16 June 1989 |
| Creators | Chavasit, Visith |
| Contributors | Hudson, J. Michael |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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