In the present study, the textural changes induced in Chinese
waterchestnuts by physical and chemical means were of prime concern.
After being subjected to chemical and heat treatments, the
corms were analyzed to relate the chemical changes with the physical
changes in the corms.
Chinese waterchestnuts were peeled, filled in cans with one
hundred ml of various concentrations of hydrochloric acid and sodium
hydroxide, and heated in the retort for one hour at 240°F
(115.6°C). Distilled water was used for the control samples.
Physical and chemical examinations followed, and the results of
the texture measurements were compared with the chemical composition
of the corms.
A physical measurement of texture was obtained by using the
Maryland Shear-press.
The drained weights, total solids, alcohol insoluble solids,
ash, total sugars, cellulose, starch, total pectins including three
pectic fractions, phosphorus, calcium and potassium were determined.
Measurements of pH, degrees Brix, and color intensity were made on
the processed liquid.
The results indicated the following conclusions:
1. Processing in both acid and alkali had a definite softening
effect on the Chinese waterchestnut corm.
2. The highest correlation was obtained between texture (as
measured by maximum force and total work) and cellulose in both
the acid and alkali series.
3. The hydrolysis of cellulose and starch was more complete
in the acid series.
4. A linear relationship existed between the pH of the acid
series and texture.
5. The samples processed in acid showed more consistent
trends than did the alkali processed samples.
6. There was a darkening in color as the concentration of
both the acid and alkali increased.
7. The percentages of total solids and AIS showed a definite
trend when compared with the texture measurements.
8. The relationship between firmness of the corms and the
pectic substances in this study was a complex relationship due to the
reactive nature of the pectic compounds. / Graduation date: 1964
| Identifer | oai:union.ndltd.org:ORGSU/oai:ir.library.oregonstate.edu:1957/28168 |
| Date | 28 February 1964 |
| Creators | Wong, Marianne Mui-Ling |
| Contributors | Dietz, James H. |
| Source Sets | Oregon State University |
| Language | en_US |
| Detected Language | English |
| Type | Thesis/Dissertation |
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