Physico-fracture Characteristics of Makhana (Euryale ferox) Seeds

Figures & data

Table 1. Axial dimensions of Makhana seeds as influenced by moisture content.

Moisture content (% d.b.)	Length (mm)	Breadth (mm)	Thickness (mm)	Da (mm)*	Dp (mm)*	Dg (mm)*
14.5	12.06	11.88	11.88	11.82 ± 0.98	11.88 ± 0.95	11.80 ± 0.98
14.3	11.6	11.6	11.18	11.46 ± 0.97	11.4 ± 0.96	11.43 ± 0.99
13.8	11. 29	11.07	10.71	11.02 ± 0.95	11.02 ± 0.97	11.02 ± 0.98

*Values are represented as means ± standard deviation (n = 5).

Table 2. Physical properties of Makhana.

Sl No	Moisture (% d.b.)	Sphericity	Angle of repose (°)	Static coefficient of friction			Bulk density (kg/m^3)	True density (kg/m3)
				Mild Steel	Stainless Steel	Glass
1	14.5	0.975	50.19	0.29	0.27	0.29	638.46	1106.66
2	14.3	0.985	48.24	0.27	0.25	0.26	587.12	1090.10
3	13.8	0.978	46.12	0.25	0.23	0.24	515.38	957.142

Table 3. Effect of temperature on moisture content, rupture force, and deformation at rupture for makhana seed hull.

Sample	Temperature °C	Moisture content (% d.b.)	Rupture force (N)*		Deformation (mm)*		Rupture energy (mJ)
			2 min	4 min	2 min	4 min	2 min	4 min
1	150	15.15	588.59 ± 2.3	557.81 ± 3.2	3.66 ± 0.6	2.95 ± 0.4	1077.12	822.77
2	175	14.22	542.36 ± 3.1	525.68 ± 2.8	3.39 ± 0.4	2.86 ± 0.5	919.30	751.72
3	200	13.32	510.45 ± 1.9	489.29 ± 3.5	3.20 ± 0.5	2.31 ± 0.2	816.72	565.13
4	225	11.89	495.29 ± 2.5	449.03 ± 2.4	2.81 ± 0.3	2.01 ± 0.3	695.88	451.27
5	250	10.28	433.45 ± 2.8	369.42 ± 2.6	2.71 ± 0.5	1.69 ± 0.4	587.32	312.16

*Values are mean ± standard deviation (n = 5).

Figure 1. Force-deformation characteristics of Makhana seed under different period of roasting.

Figure 2. Effect of moisture content of Makhana seed on energy absorbed per unit volume at rupture.

Figure 3. Microscopic view of ruptured Makhana seed roasted for 4±0.5 min at (a) 150°C and (b) 250°C.