• Korean Journal of Food Science and Technology
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• v.36 no.4
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• pp.594-597
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• 2004

Effects of various levels and molecular weights (MWs) of chitooligosaccharides and chitosan with pork salt-soluble protein (SSP) on pH, moisture (%), viscosity, and hardness of protein-chitosan mixtures were determined in a model study. Mixtures of 0.15, 0.3, and 0.45% chitosan at various MWs (Low, 1.5 kDa; Medium, 30-50 kDa; High, 200 kDa) were dissolved in 3% SSP solution for measurement of pH and viscosity at $20^{\circ}C$. pH value increased with addition of 0.45% low MW of chitooligosacchearides into SSP (p<0.05), whereas decreased with addition of 0.45% medium MW and 0.3% or higher level of high MW chitosan. Viscosity increased with addition of more than 0.3% either medium or high MW chitosan (p<0.05), as compared to mixture with low MW chitolligosaccharide and control (p<0.05). No differences in gel pH, moisture, and hardness values were observed among treatments (p>0.05). Further study will be performed to evaluate rheological properties actual meat products with various levels and MWs of chitosan.

• Journal of Microbiology and Biotechnology
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• v.23 no.1
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• pp.15-21
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• 2013

We previously observed that Bacillus subtilis spores from sspE mutants presented a lower germination capacity in media containing high salt concentrations (0.9M NaCl). This deficiency was attributed to the absence of SASP-E (gamma-type small-acid-soluble protein), rich in osmocompatible amino acids released by degradation. Herein we observed that, in addition, this mutant spore presented a reduced capacity to use L-alanine as germinant (L-ala pathway), required longer times to germinate in calcium dipicolinate ($Ca^{2+}$-DPA), but germinated well in asparagine, glucose, fructose, and potassium chloride (AGFK pathway). Moreover, mild sonic treatment of mutant spores partially recovered their germination capacity in L-ala. Spore qualities were also altered, since sporulating colonies from the sspE mutant showed a pale brownish color, a higher adherence to agar plates, and lower autofluorescence, properties related to their spore coat content. Furthermore, biochemical analysis showed a reduced partition in hexadecane and a higher content of $Ca^{2+}$-DPA when compared with its isogenic wild-type control. Coat protein preparations showed a different electrophoretic pattern, in particular when detected with antibodies against CotG and CotE. The complementation with a wild-type sspE gene in a plasmid allowed for recovering the wild-type coat phenotype. This is the first report of a direct involvement of SASP-E in the spore coat assembly during the differentiation program of sporulation.

• Asian-Australasian Journal of Animal Sciences
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• v.28 no.7
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• pp.1020-1027
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• 2015

The combined effect of tumbling marination methods (vacuum continuous tumbling marination, CT; vacuum intermittent tumbling marination, IT) and effective tumbling time (4, 6, 8, and 10 h) on the water status and protein properties of prepared pork chops was investigated. Results showed that regardless of tumbling time, CT method significantly decreased the muscle fiber diameter (MD) and significantly increased the total moisture content, product yield, salt soluble proteins (SSP) solubility, immobilized water component (p<0.05) compared with IT method. With the effective tumbling time increased from 4 h to 10 h, the fat content and the MD were significantly decreased (p<0.05), whereas the SSP solubility of prepared pork chops increased firstly and then decreased. Besides, an interactive effect between CT method and effective tumbling time was also observed for the chemical composition and proportion of immobilized water (p<0.05). These results demonstrated that CT method of 8 h was the most beneficial for improving the muscle structure and water distribution status, increasing the water-binding capacity and accelerating the marinade efficiency of pork chops; and thus, it should be chosen as the most optimal treatment method for the processing production of prepared pork chops.

• Food Science of Animal Resources
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• v.25 no.3
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• pp.285-294
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• 2005

The objective of this study was to evaluate the physico-chemical properties and flavor compounds of sausages with various levels and molecular weight (MWs) of chitosans, during storage at $4^{\circ}C$. Various MWs (Low: 1.5 kDa; Medium: $30{\sim}50$ kDa; High: 200 kDa) and two levels (0.3 and $0.6\%$) of chiosans were dissolved and measured the viscosity at $4^{\circ}C$, pH values were not affected (p>0.05) by either MWs or levels of chitosans. The addition or high MWs or chitosan into the pork salt soluble protein (SSP) increased the viscosity, whereas no differences were observed in low and medium MWs of chitosan. Textural profile analysis (TPA) was affected by the addition of medium or high MWs of chitosan. As a result, the addition of medium of chitosan increased the hardness, gumminess, chewiness, cohesiveness and springiness values, whereas increased level of chitosan didn't affect TPA values, except few cases. Approximately twenty-nine flavor compounds were identified in the low-fat and regular-fat sausages, however the addition of chitosans didn't impair the flavor composition of the sausages, These results indicated that the addition of chitosans didn't affect the flavor profiles, but affected the textural properties in the sausages, especially MWs higher than 30 kDa.