| Topic: | The influence of pulsed vacuum stimulation (PVS) on diffusion coefficients of
calcium ion, surface textural properties, and microstructural characteristics of
calcium alginate gel |
| Abstract: | A number of novel applications of calcium alginate (CA) have been recently proposed. However,
the gelation process of CA gel is time and energy consuming, as well as costly, leading to limited
practical applications. This is partially attributed to the poor calcium ion diffusion rate under the
ambient pressure. Presently, the application of puled vacuum stimulation (PVS) has been
implemented as an alternative treatment to improve the diffusion behavior. Therefore, the utilization
of PVS could be a promising strategy to enhance the rate of calcium ion diffusion in CA gel. In this
study, we investigated the effect of PVS at different depressurization levels (8, 35, 61 kPa) and
intermittent depressurized cycles (3, 6, 9 cycles at 35 kPa) on the diffusion coefficients of calcium
ion (D), textural and microstructural characteristics of CA gel. The result showed that PVS increased
the gel thickness (approximately 2-10%) and improved D by 1-3 times when compared with the
control case that was processed under ambient pressure (~101 kPa). An increase of depressurization
levels and intermittent depressurized cycles resulted in a significant increase of Young’s modulus
of the CA gel, whereas surface rupture strength and shrinkage were decreased. This was because
under depressurization, the internal air bubbles tended to move from the core toward the outer crust
of the CA gel, leading to a more compact and dense core but a more porosity inside the outer crust
of the CA gel. The scanning electron microscope (SEM) images exhibited the surface roughness and
multiple layer formation in the outer crust of PVS treated CA gel. For an optimal performance, an
application of PVS at the depressurization level of 35 kPa with 6 intermittent depressurized cycles
was recommended because a more intense stimulation showed extremely poor D and created huge
internal voids, which were caused by a merging of soluble gas in the CA matrix. Understanding the
effect of PVS on the diffusion coefficients of calcium ion, structural and textural characteristics of
CA gel is the key to accelerate the design of delivery system in food and biotechnological
applications. |
| Author: | 59403801 : Miss Janjira Jinnoros
Asst. Prof. Bhundit Innawong, Ph.D |
| File: | แฟ้มข้อมูล(pdf)
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| Journal ranking: | มีการตีพิมพ์ในวารสารวิชาการระดับนานาชาติที่ปรากฎในฐานข้อมูลการจัดอันดับวารสาร SJR(SCImago Journal Rank:www.scimagojr.com)โดยวารสารนั้นถูกจัดอยู่ในควอไทล์ที่ 1 หรือ 2 (Q1 หรือ Q2) ในปีล่าสุด ใน subject category ที่ตีพิมพ์ หรือมีการตีพิมพ์ในวารสารวิชาการระดับนานาชาติที่ปรากฎในฐานข้อมูลสากล ISI |