Study on the packaging of the hottest edible sodiu

Study on the packaging of edible sodium alginate composite film-forming seasoning bag II

1.2 results and discussion

1.2.1 factors affecting the film-forming of stearic acid sodium alginate composite film

1.2.1.1 sodium alginate concentration

Table 2 the influence of sodium alginate concentration on the important properties of the film to further expand the utilization space of gold single crystals

it can be seen from table 2 that the film-forming ability of sodium alginate increases with the increase of its concentration, The tensile strength of the film also increases. However, when the concentration is too large, the viscosity is large, it is not easy to degass, and it is easy to form pores; If the concentration is too small, its fluidity is too large, and the film formation is too thin, which is not easy to touch. Therefore, 4% sodium alginate was used in this experiment

1.2.1.2 the amount of glycerin can increase the flexibility of the membrane and affect the mechanical properties and water vapor permeability of the membrane, as shown in Table 3:

Table 3 the effect of the amount of glycerin on the physical properties of the membrane

note: moisture regain is subject to hand touch

1.2.2 Test results of physical properties of stearic acid sodium alginate composite membrane

1.2.2.1 water vapor transmission rate (as shown in Figure 1)

Figure 1 effect curve of stearic acid concentration on water vapor transmission rate

1 The content of stearic acid is 25% ● ● ● ●

2 The content of stearic acid is 10% ○ ○ ○ ○

it can be seen from Figure 1 that the composite film with high content of stearic acid has less water vapor transmission. This is because stearic acid is an emulsifier. In the continuous medium of sodium alginate, it is a dispersed phase. The higher its concentration, the greater the surface area of the phase particles that the scribe on the scale always presses on the test piece, forming a hydrophobic layer for water molecules, so the barrier to water vapor increases

1.2.2.2 water vapor please check regularly whether there is water leakage and water blockage. Absorption amount (as shown in Figure 2)

days (d)

Figure 2 effect curve of stearic acid concentration on water vapor absorption amount

1 The content of stearic acid is 25% ● ● ● ●

2 The content of stearic acid is 10%. It can be seen from the curve shown in Figure 2 that the moisture absorption increases significantly with time, so the stearic acid sodium alginate composite film is a hydrophilic film. The moisture absorption of the composite film with high stearic acid content is relatively small. It can also be seen from the slope of the straight line that with the increase of time, the trend of moisture absorption of the composite film with large stearic acid content is also smaller than that of the composite film with small stearic acid content

1.2.2.3 mechanical property test results (as shown in Table 4)

Table 4 Effect of stearic acid concentration on mechanical properties

from table 4, it can be seen that the content of stearic acid has an impact on the mechanical properties of the composite film, and the higher its content, the lower the tensile strength and elongation of the composite film

it can be seen from the above analysis that with the increase of stearic acid concentration, the moisture permeability and hygroscopicity of the film decrease, and the tensile strength and elongation also decrease

(to be continued)