Studies on some important physical properties of Char (Buchanania lanzan) seeds
Abstract
Physical and mechanical properties of Chironji (Buchanania lanzan) seeds are necessary for the design of equipment for decortications of chironji seeds and to be handle, transport, and process and store the chironji kernels. The physical properties of chironji seeds and kernels have been evaluated as a function of chironji seeds moisture content varying from 8.97% to 13.09% (wb) seeds. In this range, seeds length, width, thickness and mass with geometrical mean diameter increases from 8.90 mm to 9.30 mm, 7.93 mm to 8.50 mm, 6.02 to 6.60mm, 0.19 to 0.22 g respectively; the seeds sphericity, aspect ratio and 1000 seeds mass increases from 84.40 to 87.50, 89.10 to 91.39 and 228g to 252g respectively; the seeds bulk density, true density, porosity and coefficient of friction increases from 562.5 to 527.5 kg/m3, 906.6 to 815.0 kg/m3, 35.58 to 37.75 and 0.643 to 0.717, 0.263 to 0.326, 0.673 to 0.821 and 0.347 to 0.400 for rubber, glass, stainless steel and sun-mika respectively; the seeds and angle of repose and specific heat increases from 19.29° to 24.70° and 0.05 to 0.10 kJ/g°c respectively.
Full Text
Tables and figures are in the full-text PDF.
Introduction
Chironji (Buchanania lanzan) is common tree in dry deciduous forests. It is endemic to tropical dry deciduous forest of India. Chironji (Buchanania lanzan), belongs to family Anacardiaceae. It is a medium sized tree, with straight, cylindrical trunk, up to 10-15 m height and tomentose branches. This multipurpose tree provides food, fuel, fodder, timber and medicine to the local community [7]. Bark is rough, dark grey or black, fissured into prominent squares, 1.25-1.75 cm thick, and is reddish inside. Its leaves are thickly coriaceous, broadly oblong with a rounded base. Leaves have 10-20 pairs of straight, parallel veins. Fruits are drupe, ovoid or globose, black, 8-12 mm in diameter with hard stones. Unripe fruit are green in colour. The chironji seed is small sized slightly flattened and has an almond-like flavor and highly nutritious. There is a problem in the storage due to high oil content and an association of fungi with seeds.
Materials and Methods
The raw material chironji was collected from different region of the Chhattisgarh for the present investigation. The material was properly cleaned and drying after remove of outer skins or pulps from the chironji seeds to have a uniform sample. They were further cleaned manually to remove foreign matters and other impurities like stones. Different properties of chironji such as moisture content, thousand grain mass, size and shape, specific gravity, bulk density, true density, porosity, and angle of repose were determined using standard techniques. In order to study the effect of moisture content on different physical and engineering properties of chironji seeds, the moisture content of the sample was varied. The moisture content of the chironji seeds was increased by adding the water on it. Calculated amount of water was added to the known weight of samples to obtain the samples of desired moisture content.
Moisture Content
To calculate the moisture to be added, the sample of weight W 2 at higher moisture M 2 was found out by the following expression:
Where, M 1 = Initial moisture content; M 1 = Final moisture content; W 1 = Initial weight of the sample; and W 2 = Final weight of the sample.
Thousand Grains Mass
The 1000 grain mass was determined by selecting different lots of 1000 sound grains by counting from general lot, weighing them using electronic balance. The average value of 3 replications was taken.
Size and Shape
The geometric mean diameter (Dp) of the calculated by using the following relationship [11] D p = (LWT) 1/3 (2)
The degree of sphericity () was calculated the following formula as described by [11] ∅ = (L × B × T) Where, L = Length, (mm); W = Width, (mm); and T = Thickness, (mm).
True Density
The true density of a nut or seed is defined as the ratio of the mass of a sample of a nut or seed to the solid volume occupied by the sample. The nuts and seeds volume and their true density were determined using the liquid displacement method. Toluene (C 7 H 8 ) was used.
Bulk Density
Bulk density (b) = weight of the grains volume occupied by grains (6)
Porosity (ε)
Where, t = True density; and b = Bulk density.
Angle of Repose
Where, = Angle of repose (°); H a = Height of the cone, (cm); H b = Height of the platform, (cm); and D = Diameter of the platform, (cm).
Co-efficient of Internal Friction
Where, µ = Co-efficient of internal friction; N = Normal forces in the internal friction (N); and F = Frictional forces in internal friction (N).
Specific Heat
Specific heat = (amount of heat) (mass of substance) (temperature changes) (10)
Results and Discussion
Angle of Repose
Table 1 shows the experimental values of the angle of repose for the chironji seeds at various moisture levels in the range of 8.97 to 13.09 (wb). A plot of the experimentally determined data on angle of repose corresponding to various moisture contents is represented in Fig. 2. It increased linearly from 19°29' to 24°70' with the increased in seed moisture. It may be due to the rough surface of chironji seed imposing resistance to the seeds from sliding on each other.
Linear Dimensions of Seeds
The variation of the length, width and thickness with mass of the seeds and kernels is displayed in Fig. 2 and3. All the dimensions increase linearly with seeds moisture content is increases.
Sphericity ()
The effect of moisture content on sphericity of chironji seed is given in the consolidated Table 1 and its graphical representation is also provided in Fig 3. This is due to the fact that the seed swells initially from its breadth and thickness axes to some extent upon moisture absorption, but beyond a certain limit due to further soaking the seed tends to expand on its major diameter. Major diameter as denominator in the expression sphericity decreased. The relationship between moisture content and sphericity of chironji seeds was found to be non-linear.
Thousand -Grain Mass
The thousand-grain mass for chironji seed was determined at different moisture contents ranging from 8.97 to 13.09 per cent (wb) increased linearly with increase in moisture content respectively. The increase in mass of the seeds ranged from 228 -252 g. The graphical representation of effect of moisture content on thousand-grain mass is shown in Fig. 4.
Geometric Mean Diameter
Table 1 show that the equivalent diameter of the chironji seed increased with the increase in moisture content. The equivalent diameter varied from 7.79 to 8.05 mm. This was due to the fact that with the increase in moisture content the size of the seeds increased upon swelling which in turn increased the diameters (all the three). The change in equivalent diameter of the chironji seed with the increase in moisture contents is also shown in Fig. 4.
Bulk Density
The bulk density of chironji seeds decreased from 562.5kg/m 3 to 527.5 kg/m 3 Table 2 and. Statistical analysis showed that the values of bulk density at all moisture levels are showing significant difference with each other. The grand mean was observed as 544.92kg/m 3 and the standard deviation among the values was 15.49 per cent.
True Density
The true density of chironji seeds determined at different moisture contents ranging from 8.97 to 13.09 per cent (wb) decreased with the increase in moisture content Table 2.
True density of chironji seeds was observed in the range of 906.6 kg/m 3 to 815 kg/m 3 . Statistical analysis showed that the values of true density at all moisture levels are showing significant difference among each other. The grand mean was 865.4 g/ml and the standard deviation was observed as 39.74 per cent.
Porosity ()
The estimated porosity of chironji seeds was found to decrease with the increase in moisture content Table 2. The porosity value for chironji seeds was calculated to be 37.74 to 35.58 per cent for the moisture range of 8.97 to 13.09 per cent (wb) Fig. 6. The reason for this decrease is that as the chironji seeds gain moisture, its volume increases, thus the number of seeds and in a fixed volume decreases. Since the number of seeds per unit volume decreases, the porosity, i.e. the per cent pore spaces between the particles also decrease. Further, porosity depends on the bulk density as well as true densities of the material and the magnitude of variation also depends on the values of densities. Statistical analysis showed that the standard deviation was 1.05 per cent. The grand mean of porosity of the seeds and kernels was observed as 36.79 per cent.
From Table 2 it can be noticed that all the values of porosity are showing non-significant difference with each other.
Coefficient of External Friction (µ)
The static coefficient of friction for external surfaces for chironji seeds determined with respect to four different structural surface is shown in Table 2. It is observed that the static coefficient of friction for chironji seeds increased with increase in moisture content on all surfaces. The static coefficient of friction was greatest on mild steel surface (0.673 to 0.821) than rubber (0.643 to 0.717) and plywood (0.347 to 0.400) followed by the least for glass (0.243 to 0.326) respectively.
Specific Heat (Cp)
The variation in specific heat with moisture content and temperature of chironji seeds is presented in Table 1 and Fig
6.
The specific heat of chironji seed varied from 0.05 to 1.0 kJ/g°C for the experimental range of variables studied.
Conclusion
Angle of repose was increased linearly with the increase in seeds moisture. The variation of the length, width, thickness and mass of the seeds is increase linearly with moisture content. The value of sphericity decreased if moisture content of seeds increased. The thousand-grain mass for chironji seeds moisture contents increases linearly with increase in moisture content. The equivalent diameter of the chironji seeds increased with the increase in moisture content. The bulk density of chironji seeds decreased with increases moisture content. The true density of chironji seeds was decreased with the increase in moisture content.
The porosity value for chironji seeds was increases for increasing of moisture content. It is observed that the static coefficient of friction for chironji seeds increased with increase in moisture content on all surfaces. The variation in specific heat with moisture content and temperature of chironji seeds.
References
- Aghbashlo M, Kianmehr MH, Beygi SRH. Specific heat and thermal conductivity of berberis fruit (Berberis vulgaris). Am J Agric Biol Sci. 2008;3(1):330-336.
- Amin MN, Hossain MA, Roy KC. Effect of moisture content on some physical properties of lentil seed. J Food Eng. 2004;65(1):83-87.
- Aydin C. Physical properties of almond nut and kernel. J Food Eng. 2003;60:315-320.
- Calisir S, Marakoglu T, Ogut H, Ozturk O. Physical properties of rapeseed. J Food Eng. 2005;69:61-66.
- Deshpande SD, Bal S, Ojha TP. Physical properties of soybean. J Agric Engg Res. 1993;56(1):89-98.
- Dutta SK, Nema VK, Bhardwaj RK. Physical properties of gram. J Agric Engg Res. 1988;39(5):259-268.
- Dwivedi SV, Singh SN, Singh R. Conservation of chironji and cultivation of off-season rainfed tomato. Curr Sci. 2012;102(2):25-26.
- Gupta RK, Das SK. Physical properties of sunflower seeds. J Agric Engg Res. 1997;66(1):1-8.
- Hsu MH, Mannapperuma JD, Singh RP. Physical and thermal properties of pistachios. J Agric Engg Res. 1991;49:311-321.
- Joshi DC, Das SK, Mukherjee RK. Physical properties of pumpkin seeds. J Agric Engg Res. 1993;54(3):219291.
- Mohsenin NN. Physical properties of plant and animal materials. New York: Gordon and Breach Science Publishers; 1996.
- Singh KK, Goswami TK. Physical properties of cumin seed. J Agric Engg Res. 1996;64(1):93-98.
- Viswanathan R, Varadharaju N, Gothandapani L, Sreenarayan VV. Effect of moisture content on angle of repose and bulk density of selected food grains. J Food Sci Technol. 1990;27(3):133-135.
How this paper connects to the literature. Drag to explore, click any node to open that paper.