- Email: [email protected]
Nutritional and physical properties of hackberry (Celtis australis L.)
Journal of Food Engineering 54 (2002) 241–247 www.elsevier.com/locate/jfoodeng
Nutritional and physical properties of hackberry (Celtis australis L.) Fikret Demır a
€ zcan b, Haydar Hacisefero , Hakan Do gan a, Musa O gullari
a,*
a
Faculty of Agriculture, Department of Agricultural Machinery, Selcßuk University, 42031 Konya, Turkey b Faculty of Agriculture, Deparment of Food Engineering, Selcßuk University, 42031 Konya, Turkey Received 3 June 2001; accepted 30 October 2001
Abstract Nutritional and physical properties of ripe hackberry fruits (Celtis australis L.) from Kastamonu were determined. Ash, crude oil, crude energy, crude fiber, crude protein and minerals (Na, P, K, Ca, Mn, B, Ba, Se, etc.) contents of completely ripe fruits were determined. Also, physical properties such as length and diameter of fruit, unit mass, volume of fruit, geometric mean diameter, sphericity, surface area, bulk density, fruit density, porosity, projected area, terminal velocity, 1000 fruits mass, static and dynamic coefficient of friciton were measured at three moisture content levels. The average length, diameter, unit mass, volume of fruit, the geometric mean diameter, sphericity and surface area were established as 9.34 mm, 8.07 mm, 0.233 g, 277:85 mm3 , 8.37 mm, 0.89 and 206:4 mm2 at 15.25%, respectively, moisture content (w.b.). Studies on rewetted fruit showed that as moisture content increased from 15.25% to 50.42% wet basis (w.b.), bulk density decreased from 595.1 to 535:9 kg=m3 , fruit density increased from 826.1 to 1105:9 kg=m3 . The porosity, projected area, terminal velocity, 1000 fruit mass increased from 30.97% to 53.84%, from 54.91 to 74:63 mm2 , from 4.73 to 10.47 m/s, from 247.5 to 594 g, respectively, for the same moisture increase. The coefficient of static friction on rubber, plywood and galvanized steel increased from 0.5 to 0.55, 0.41 to 0.54 and 0.30 to 0.48, respectively, when the fruit moisture content increased from 15.25 to 50.42%. The coefficient of dynamic friction increased from 0.36 to 0.5, 0.31 to 0.43 and 0.22 to 0.35 on rubber, plywood and galvanized steel, respectively, for the same moisture range. 2002 Elsevier Science Ltd. All rights reserved. Keywords: Hackberry (Celtis australis L.); Ulmaceae; Nutritional properties; Physical properties
1. Introduction Hackberry (nettle tree, ßcitlembik, ßcıtlak, ßcıtlık, ßcitemek, ßcitemik, ılıcß) are the fruits of Celtis australis in the Ulmaceae family. Hackberry wildly grows in various regions (especially in mediterranean, north, west and north-west Anatolia) of Turkey (Baytop, 1994). Any of the several trees of the genus Celtis, with about 70 species in the elm family (Ulmaceae), that are valued for their wood or ornamental qualities. They are distributed primarily in the temperate and tropical areas. The eastern North American tree called hackberry or nettle tree is C. occidentalis. It has bright green elmlike leaves, which often have three prominent veins arising from the base of the blade and edible pea-sized purplish-black fruits attractive to birds. The bark is sometimes covered with wartlike bumps. It is often
*
Corresponding author. E-mail address: [email protected] (F. Demır).
planted as a street tree, attaining heights of from 12 to 30 m. Mississippi hackberry or sugarberry (C. laevigata) is a shorter tree native to moist soils of central North America. The Mediterranean hackberry or European nettle tree (C. australis) is an ornamental tree that has lance-shaped, gray-green leaves and larger edible fruits. Some West African species produce valuable timber (Anonymous, 2000; Bean, 1981; Chiej, 1984; Facciola, 1990; Huxley, 1992) The fruits are astringent, lenitive and stomachic (Chevallier, 1996; Chiej, 1984). The fruit, unripe fruit, is often considered to be very effective medicinally (Chevallier, 1996). A decoction of both leaves and fruit is used in the treatment of amenorrhea, heavy menstrual and intermenstrual bleeding and colic (Chopra, Nayar, & Chopra, 1986; Duke & Ayensu, 1985). The decoction can also be used to astringe the mucous membranes in the treatment of diarrhea, dysentery and peptic ulcers (Anonymous, 2001; Chevallier, 1996). Eighty species were found in the northern hemisphere and southern Africa. About 17 species are known in
0260-8774/02/$ - see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S 0 2 6 0 - 8 7 7 4 ( 0 1 ) 0 0 2 1 0 - 2
242
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Nomenclature D Dg L M Mc M1000 P Pb Pk q R
diameter of fruit (mm) geometric mean diameter (mm) length of fruit (mm) unit mass of fruit (g) moisture content (%) 1000 fruit mass (g) projected area ðmm2 Þ bulk density ðkg=m3 Þ fruit density ðkg=m3 Þ torque arm (cm) (10.5 cm) Correlation coefficient
horticulture. The pollen of some species is suspected to cause hayfever (Wodehouse, 1971). To optimum of threshing performance, processes of pneumatic conveying, storing and other processes of hackberry fruits, its physical properties must be known. No detailed study concerning nutritional and physical properties of hackberry fruits have been performed up to now. The purpose of this study is to determine the nutritional and physical properties of wild Turkish hackberry fruits.
R2 S Ta Tm V Vt W Ø e ls ld
Coefficient of determination surface area ðmm2 Þ beginning value of the torque (N cm) average value of the torque (N cm) volume of fruit ðmm3 Þ Terminal velocity (m/s) sample weight (10 N) sphericity porosity (%) static coefficient of friction dynamic coefficient of friction
cooled at 0 C for 1 h. The sample was prepared for mineral analysis and determined in a ICP–AES (Varian– Vista) see below (Skujins, 1998). Instrument RF power Plazma gas flow rate (Ar) Auxilary gas flow rate (Ar) Viewing height Copy and reading time Copy time
ICP–AES (Varian–Vista) 0.7–1.5 kW (1.2–1.3 kW for axial) 10.5–15 l/min (radial) 15 l/min (axial) 1.5 l/min 5–12 mm 1–5 s (max 60 s) 3 s (max 100 s)
2.2. Determination of physical properties 2. Materials and methods Ripe wet mature hackberry fruits were used for all the experiments in this study. The crop was harvested at Kastamonu (Tasßk€ opr€ u) during the summer season of 2000. Hackberry fruits were kept in cooled bags for transport to the laboratory. The fruits were cleaned in an air screen cleaner to remove all foreign matter such as dust, dirt, stones and chaff as well as immature and damaged fruits. The initial moisture content of fruits was determined by using a standard method (Brusewitz, 1975; USDA, 1970). The remaining material was packed in a 2000 ml hermetic glass vessel and kept in cold storage until use. Vessels were selected randomly from the chamber, and the required fruits were taken randomly from the vessels and dried down to the desired moisture content by the vacuum oven method (Baryeh, 2001; Joshi, Das, & Mukherjee, 1993; Singh & Goswami, 1996; Suthar & Das, 1996) before tests were conducted on them. The nutritional properties of the fruits were analyzed according to AOAC (1984). Results were analyzed for statistical significance by analysis of randomized plots of factorial experimental design (Minitab, 1991).
To establish the sizes and projected areas of fruits, 10% samples were randomly taken and their linear dimensions, i.e. length (L), diameter (D) and projected area (P) were measured. Projected area of a fruit was determined using a digital camera (Kodak DC 240) and Sigma Scan Pro5 program (Ayata, Yalcßın, & Kirisßßci, 1997; Trooien & Heermann, 1992). Linear dimensions were established by using a digital vernier caliper with a sensitivity of 0.01 mm. The mass of fruit was determined on 100 randomly selected fruits and converted to a 1000 fruits basis. Fruit unit mass (M) and 1000 fruit mass ðM1000 Þ were measured with an electronic balance of 0.001 g sensitivity. € zcan, Several investigators (Baryeh, 2001; Demir & O 2001; Dehspande, Bal, & Ojha, 1993; Dutta, Nema, & Bhardwaj, 1988; Joshi et al., 1993; Mohsenin, 1970; Shepherd & Bhardwaj, 1986; Singh & Goswami, 1996) have measured these dimensions for other grains and seeds in a similar manner to determine size and shape properties. The geometric mean diameter ðDg Þ of the fruit was calculated by using the following formula (Mohsenin, 1970):
2.1. Determination of nutritional properties
Dg ¼ ðLD2 Þ1=3 :
About 1 g ground hackberry fruit was put into a small glass bottle and 5 ppm of standard was added and
The fruit volume (V) and fruit density ðPk Þ, were determined as a function of moisture content using the liquid
ð1Þ
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
displacement method. Toluene ðC7 H8 Þ was used rather than water because it is absorbed by fruits to a lesser extent. Also its surface tension is low, so it fills even shallow dips in a fruit and its dissolving power is low € €t, 1998; Singh & Goswami, 1996; (Mohsenin, 1970; O gu Sitkei, 1976). According to Jain and Bal (1997) and Mohsenin (1986), the degree of sphericity (Ø) can be expressed as follows: Ø ¼ ðLD2 Þ
1=3
=L ¼ Dg =L:
ð2Þ
This equation was used to calculate the sphericity of the fruits in the investigation. The surface area (S) of the fruit was calculated by using the following formula (Mohsenin, 1970): S ¼ ðpD2 L2 Þ=6ð2L DÞ ¼ pD2g :
ð3Þ
The bulk density ðPb Þ was determined with a weight per hectoliter tester which was calibrated in kg per hectoliter (Dehspande et al., 1993; Jain & Bal, 1997; Suthar & Das, 1996). The fruits were filled into the calibrated bucket from a height of about 15 cm and excess fruits were removed by a strike off stick. The fruits were not compacted in any-way. The porosity ðeÞ was determined by the following equation: e ¼ 1 Pb =Pk ;
ð4Þ
in which Pb and Pk are the bulk density and the fruit density, respectively, (Mohsenin, 1970; Thompson & Isaacs, 1967). The terminal velocities (or critical velocities) of fruits at different moisture content were measured using an air column. For each test, a sample was dropped into the air stream from the top of the air column, through which air was blown upwards to suspend the fruits in the air stream. The air velocity near the location of the fruit
243
suspension was measured by electronic anemometer having a least count of 0.1 m/s (Hauhouout-O‘hara, Criner, Brusewitz, & Solie, 2000; Joshi et al., 1993; Mohsenin, 1986). The coefficient of friction of fruit was measured using a friction device modified by Tsang-Mui-Chung, Verma, and Wright (1984) and improved by Chung and Verma (1989). Also, both the static and dynamic coefficient of friction with an applied torque were measured and calculated using the equation (Chung & Verma, 1989): ls ¼ Ta =Wq;
ð5Þ
ld ¼ Tm =Wq;
ð6Þ
where ls equals static coefficient of friction, Ta equals beginning value of torque, ld equals dynamic coefficient of friction, Tm equals average value of the torque, q the length of torque arm, and W is the weight of fruits to calculate the dynamic and static coefficients of friction, the average value of the torque during the rotation of the disk and the maximum value of torque obtained as the disk started to rotate were used on the rotating surface.
3. Results and discussion 3.1. Nutritional properties The nutritional properties of hackberry fruits are given in Table 1. Crude oil, crude protein, crude fiber, crude energy and ash contents were found as 6.70%, 19.32%, 4.40%, 16.2 kcal/g and 15.29%, respectively. Also, Na, K, P, Mn, Ca, B, Ba, Ms and Se were established as major minerals in fruits. Some minerals such as Na, K, P, Ca, Mg, Mn and Zn of hackberry fruits were found to be higher compared with those of
Table 1 Nutritional properties of fruits Ash (%) Dry matter (%) Crude oil (%) Na (mg/kg) P (mg/kg) K (mg/kg) Fe (ppm) Zn (ppm) Mn (ppm) Ca (ppm) Ag (ppm) Al (ppm) As (ppm) B (ppm) Ba (ppm) Ti (ppm) V (ppm)
15.29 90.23 6.70 59.515 5.755 1519.59 31.1 3523.66 143.04 21.365 1.725 3.46 0.15 22.495 1.245 43973.09 251.11 2.587 0.267 18.63 1.43 12.88 1.35 64.4 1.56 264.42 5.63 1.145 0.125 0.845 0.005
Crude energy (kcal/g) Crude fiber (%) Crude protein (%) Bi (ppm) Co (ppm) Cd (ppm) Cr (ppm) Cu (ppm) Ga (ppm) In (ppm) Li (ppm) Mg (ppm) Ni (ppm) Pb (ppm) Se (ppm) Sr (ppm)
16.2 4.40 19.32 11.895 0.355 2.30 0.121 2.20 3.105 0.595 1.105 0.105 0.18 0.11 2.43 0.135 4.66 0.168 6732.5 69.93 1.275 0.125 4.17 0.147 18.28 0.315 234.615 7.115
244
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Table 2 Means and standard errors of fruit linear dimensions and linear dimensional dependent properties at different moisture content levels Fruit dimensions
15.25% w.b.
32.65% w.b.
50.42% w.b.
Diameter (D), mm Length (L), mm Volume (V), mm3 Geometric mean diameter (Dg ), mm Sphericity (Ø) Surface area (S), mm2
8.069 0.129 9.347 0.154 277.854 12.822 8.374 0.124 0.895 0.007 206.411 6.339
9.0964 0.093 10.2611 0.247 395.5629 13.464 9.3552 0.134 0.9119 0.009 260.7075 6.063
9.4702 0.272 10.7295 0.460 448.36 39.433 9.7534 0.296 0.9099 0.020 283.2485 16.793
The coefficients of correlation (Table 3) show that the D=L, D=V , D=Dg , D=Ø and D=S rations are highly significant. This indicates that the length, mass, volume, the geometric mean diameter, sphericity and surface area are closely related to the diameter of fruit. The relationship between the diameter (D) and other dimensions (M; V ; Dg ; Ø; S) for fruit can be represented by the following regression equation: D ¼ 3:41 0:00277M þ 0:00163V þ 0:906Dg þ 4:24Ø 0:00224S
Fig. 1. Frequency distribution curves of fruit dimensions at 15.25% m.c.w.b.
€ zcan, 2001; rosa and peanut (Baryeh, 2001; Demir & O € Ozcan & Akbulut, 1998). 3.2. Physical properties Table 2 shows the size distribution of the hackberry fruits. The frequency distribution curves (Fig. 1) for the mean values of the dimensions show a trend towards a normal distribution. About 83% of the fruits had a diameter ranging from 8.0 to 8.3 mm. The following general expression can be used to describe the relationship among the average dimensions of the fruits at 15.25% (w.b.) moisture content: D ¼ 0:863L ¼ 34:56M ¼ 0:029V ¼ 0:963Dg ¼ 9:007Ø ¼ 0:0390S:
ð7Þ
ðR2 ¼ 1Þ:
ð8Þ
The fruit (true) density of hackberry fruits at different moisture levels varied from 826.1 to 1105:9 kg=m3 (Fig. 2) and indicated an increase in fruit density with an increase in moisture content. The variations in fruit density with moisture content of hackberry fruit can be represented by the following correlations: Pk ¼ 704:93 þ 7:957Mc
ðR2 ¼ 1Þ:
ð9Þ
The values of the bulk density for fruits at different moisture levels varied from 595.1 to 535:9 kg=m3 (Fig. 3) and indicated a decrease in bulk density with an increase in moisture content. The bulk density ðPb Þ of fruit was found to have the following relationships with moisture content ðMc Þ: Pb ¼ 619:06 1:6815Mc
ðR2 ¼ 0:9904Þ:
ð10Þ
Since the porosity depends on the bulk as well as true or fruit densities, the magnitude of variation in porosity depends on these factors only. The porosity of hackberry fruit was found to increase with increase in moisture content from 15.25% to 50.42% w.b. as shown
Table 3 Correlation of fruit linear dimensions and linear dimensional dependent properties at 15.25% moisture content Particulars
Ratio
Degrees of freedom
Correlation coefficient ðR2 Þ
D=L D=V D=Dg D=Ø D=S
0.863 0.0290 0.963 9.007 0.0390
99 99 99 99 99
0.625 0.978 0.960 0.459 0.950
• Significant at 1% level. • D=L diameter/length, D=V diameter/volume, D=Dg diameter/geometric mean diameter. • D=Ø diameter/sphericity, D=S diameter surface area.
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
245
Fig. 2. Effect of moisture content on fruit density.
Fig. 5. Effect of moisture content on projected area.
Fig. 3. Effect of moisture content on bulk density.
Fig. 6. Effect of moisture content on terminal velocity.
Fig. 4. Effect of moisture content on porosity.
Fig. 7. Effect of moisture content on 1000 fruit mass.
in Fig. 4. The relationship between the porosity ðeÞ and moisture content ðMc Þ for fruit derived from the data was: e ¼ 21:806 þ 0:6498Mc
ðR2 ¼ 0:9876Þ:
ð11Þ
The form of the plot is similar to that for pigeon pea as found by Shepherd and Bhardwaj (1986). C ß armen (1996) reported a similar increase in porosity from 27.5% to 32.2% for lentil. The projected area of hackberry fruit (Fig. 5) increased by about 35.9%, while the moisture content of hackberry fruit increased from 15.25% to 50.42% w.b. Similar trends were reported for many other seeds (Mohsenin, 1970; Sitkei, 1986). Dehspande et al. (1993) found that the projected area of soybean grain increased from 0.813 to 0:952 cm2 , when the moisture content was increased from 6% to 26% d.b. The variation in pro-
jected area (P) with moisture content ðMc Þ of hackberry fruit can be represented by the following equation: P ¼ 47:718 þ 0:5599Mc
ðR2 ¼ 0:948Þ:
ð12Þ
The experimental results of the terminal velocity for the hackberry fruit at different moisture levels are plotted in Fig. 6. As moisture content increased, the terminal velocity was found to increase linearly. The results are similar to those reported by Kural and C ß arman (1997), but the values were higher than those for pumpkin seeds and cereals (Gorial & Callaghan, 1990; Joshi et al., 1993). The increase in terminal velocity with increase in moisture content can be attributed to the increase in mass of an individual fruit per unit frontal area presented to the air stream. The variation can be represented mathematically as:
246
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Fig. 8. Effect of moisture content on static coefficient of friction.
Fig. 9. Effect of moisture content on dynamic coefficient of friction.
Table 4 Relationships between friction coefficients and moisture content of hackberry fruit for various material surfaces
Galvanized steel Plywood Rubber
Vt ¼ 2:3975 þ 0:1631 Mc
Static
Dynamic
ls ¼ 0:2291 þ 0:0051 Mc R2 ¼ 0:9822 ls ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ls ¼ 0:3835 þ 0:0043 Mc R2 ¼ 0:999
ld ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ld ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ld ¼ 0:3835 þ 0:0043 Mc R2 ¼ 0:999
ðR2 ¼ 0:9915Þ:
ð13Þ
It can be seen from Fig. 7. that the 1000 fruit mass increases linearly with moisture content. A similar trend was reported Dehspande et al. (1993). The value of the 1000 fruit mass of hackberry at different moisture levels varied from 247.5 to 594 kg. The following linear relationship was fitted to the data: M1000 ¼ 105:2 þ 9:8475 Mc
ðR2 ¼ 0:994Þ:
The bulk density decreased from 595.1 to 535:9 kg=m3 and the fruit density increased from 826.1 to 1105:9 kg=m3 while the moisture content increased from 15.25% to 50.42% w.b. As increasing moisture content, porosity, projected area, terminal velocity, 1000 fruit mass, increased from 30.97 to 53.84%, from 54.91 to 74:63 mm2 , from 4.73 to 10.47 m/s, from 247.5 to 594 g.
ð14Þ
The static and dynamic coefficients of friction for hackberry fruit determined with respect to rubber, plywood and galvanized steel surfaces are represented in Figs. 8 and 9. At all moisture contents, both the static and dynamic coefficients of friction were greatest for hackberry fruits on rubber and least for galvanized steel, with plywood in between. As the moisture content of the fruit increased, the static and dynamic coefficients increased significantly. The relationship between the friction coefficients and moisture content of the fruit on the various surfaces is presented in (Table 4).
4. Conclusion At 15.25% m.c.w.b., the average diameter, length, unit mass, volume of fruit, the geometric diameter, sphericity and surface area of hackberry fruits were 8.07 mm, 9.34 mm, 0.233 g, 277:85 mm3 , 8.37 mm, 0.89 and 206:4 mm2 , respectively.
References Anonymous (2000). Available: http://www.britannica.com/. Anonymous (2001). Available: http://www.gardenbed.com/. AOAC. (1984). Officials methods of analysis. Association of Official Analytical Chemist (14th ed.). VA, USA: Arlington. Ayata, M., Yalcßın, M., & Kirisßßci, V. (1997). Evaluation of soiltine interaction by using image processing system. In National Symposium on Mechanisation in Agriculture (pp. 267–274). Turkey: Tokat. Baryeh, E. A. (2001). Physical properties of bambara groundnuts. Journal of Food Engineering, 47(4), 321–326. Baytop, T. (1994). The dictionary of plant in Turkey. Turkish Language Association. Publications No: 578, Ankara, Turkey (in Turkish). Bean, W. (1981). Trees and Shrubs Hardy in Great Britain. (Vols. 1–4 Suppl.). Murray. Brusewitz, G. H. (1975). Density of rewetted high moisture grains. Transactions of the ASAE, 18, 935–938. C ß armen, K. (1996). Some physical properties of lentil seeds. Journal of Agricultural Engineering Research, 63, 87–92. Chevallier, A. (1996). The encyclopedia of medicinal plants. London: Dorling Kindersley. Chiej, R. (1984). Encyclopaedia of medicinal plants. MacDonald.
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247 Chopra, R. N., Nayar, S. L., & Chopra, I. C. (1986). Glossary of Indian Medicinal Plants (Including the Supplement). Council of Scientific and Industrial Research, New Delhi. Chung, J. H., & Verma, L. R. (1989). Determination of friction coefficients of beans and peanuts. Transactions of the ASAE, 32, 745–750. Dehspande, S. D, Bal, S., & Ojha, T. P. (1993). Physical properties of soybean. Journal of Agricultural Engineering Research, 56, 89–98. € zcan, M. (2001). Chemical and technological properties Demir, F., & O of rose (Rosa canina L.) fruits grown wild in Turkey. Journal of Food Engineering, 47, 333–336. Duke, J. A., & Ayensu, E. S. (1985). Medicinal Plants of China Reference Publications. Dutta, S. K., Nema, V. K., & Bhardwaj, R. K. (1988). Physical properties of gram. Journal of Agricultural Engineering Research, 39, 259–268. Facciola, S. (1990). Cornucopia – a source book of edible plants. Kampong Publications. Gorial, B. Y., & Callaghan, J. R. (1990). Aerodynamic properties of grain/straw materials. Journal of Agricultural Engineering Research, 46, 275–290. Hauhouout-O‘hara, M., Criner, B. R., Brusewitz, G. H., & Solie, J. B. (2000). Selected physical characteristics and aerodynamic properties of cheat seed for seperation from wheat. The GIGR Journal of Scientific Research and Development, 2. Huxley, A. (1992). The new RHS dictionary of gardening. New York: MacMillan Press. Jain, R. K., & Bal, S. (1997). Physical properties of pearl millet. Journal of Agricultural Engineering Research, 66, 85–91. Joshi, D. C., Das, S. K., & Mukherjee, R. K. (1993). Physical properties of pumpkin seeds. Journal of Agricultural Engineering Research, 54, 219–229. Kural, H., & C ß arman, K. (1997). Aerodynamic properties of seed crops. In National symposium on mechanisation in agriculture (pp. 615–623). Turkey: Tokat. Minitab, C. (1991). Minitab reference manual (Release 7.1) Minitab Inc., State Coll., PA 16801, USA.
247
Mohsenin, N. N. (1970). Physical properties of plant and animal materials. New York: Gordon and Breach Science Publishers. Mohsenin, N. N. (1986). Physical properties of plants and animal materials (pp. 616–647). New York: Gordon and Breach Science Publishers. € gu €t, H. (1998). Some physical properties of white lupin. Journal of O Agricultural Engineering Research, 56, 273–277. € zcan, M., & Akbulut, M. (1998). Some physical and chemical O properties of myrtle (Myrtus communis L.) fruits. Gıda, 23, 121–123. Shepherd, H., & Bhardwaj, R. K. (1986). Moisture-dependent physical properties of pigeon pea. Journal of Agricultural Engineering Research, 35, 227–234. Singh, K. K., & Goswami, T. K. (1996). Physical properties of cumin seed. Journal of Agricultural Engineering Research, 64, 93–98. Sitkei, G. (1976). Mechanics of agricultural materials, Budapest, Akademia Kiado. Sitkei, G. (1986). Mechanics of agricultural materials. Budapest: Akademiai Kiado. Skujins, S. (1998). Handbook for ICP–AES (Varian–Vista). A short guide to vista series ICP–AES Operation. Varian Int. AG, Zug, Version 1.0, Switzerland. Suthar, S. H., & Das, S. K. (1996). Some physical properties of karingda seeds. Journal of Agricultural Engineering Research, 65, 15–22. Thompson, R. A., & Isaacs, G. W. (1967). Porosity determination of grains and seeds with air comparison pycnometer. Transactions of the ASAE, 10, 693–696. Trooien, T. P., & Heermann, D. F. (1992). Measurement and simulation of potato leaf area using image processing I, II, III. Transactions of the ASAE, 35(5), 1709–1722. Tsang-Mui-Chung, M., Verma, L. R., & Wright, M. E. (1984). A device for friction measurement of grains. Transaction of the ASAE, 27, 1938–1941. USDA, (1970). Official grain standards of the United States. US Department of Agricultural Consumer and Marketing Service Grain Division, (Revised). Wodehouse, R. P. (1971). Hayfewer plants (2nd rev.). New York: Hafner.
Nutritional and physical properties of hackberry (Celtis australis L.) Fikret Demır a
€ zcan b, Haydar Hacisefero , Hakan Do gan a, Musa O gullari
a,*
a
Faculty of Agriculture, Department of Agricultural Machinery, Selcßuk University, 42031 Konya, Turkey b Faculty of Agriculture, Deparment of Food Engineering, Selcßuk University, 42031 Konya, Turkey Received 3 June 2001; accepted 30 October 2001
Abstract Nutritional and physical properties of ripe hackberry fruits (Celtis australis L.) from Kastamonu were determined. Ash, crude oil, crude energy, crude fiber, crude protein and minerals (Na, P, K, Ca, Mn, B, Ba, Se, etc.) contents of completely ripe fruits were determined. Also, physical properties such as length and diameter of fruit, unit mass, volume of fruit, geometric mean diameter, sphericity, surface area, bulk density, fruit density, porosity, projected area, terminal velocity, 1000 fruits mass, static and dynamic coefficient of friciton were measured at three moisture content levels. The average length, diameter, unit mass, volume of fruit, the geometric mean diameter, sphericity and surface area were established as 9.34 mm, 8.07 mm, 0.233 g, 277:85 mm3 , 8.37 mm, 0.89 and 206:4 mm2 at 15.25%, respectively, moisture content (w.b.). Studies on rewetted fruit showed that as moisture content increased from 15.25% to 50.42% wet basis (w.b.), bulk density decreased from 595.1 to 535:9 kg=m3 , fruit density increased from 826.1 to 1105:9 kg=m3 . The porosity, projected area, terminal velocity, 1000 fruit mass increased from 30.97% to 53.84%, from 54.91 to 74:63 mm2 , from 4.73 to 10.47 m/s, from 247.5 to 594 g, respectively, for the same moisture increase. The coefficient of static friction on rubber, plywood and galvanized steel increased from 0.5 to 0.55, 0.41 to 0.54 and 0.30 to 0.48, respectively, when the fruit moisture content increased from 15.25 to 50.42%. The coefficient of dynamic friction increased from 0.36 to 0.5, 0.31 to 0.43 and 0.22 to 0.35 on rubber, plywood and galvanized steel, respectively, for the same moisture range. 2002 Elsevier Science Ltd. All rights reserved. Keywords: Hackberry (Celtis australis L.); Ulmaceae; Nutritional properties; Physical properties
1. Introduction Hackberry (nettle tree, ßcitlembik, ßcıtlak, ßcıtlık, ßcitemek, ßcitemik, ılıcß) are the fruits of Celtis australis in the Ulmaceae family. Hackberry wildly grows in various regions (especially in mediterranean, north, west and north-west Anatolia) of Turkey (Baytop, 1994). Any of the several trees of the genus Celtis, with about 70 species in the elm family (Ulmaceae), that are valued for their wood or ornamental qualities. They are distributed primarily in the temperate and tropical areas. The eastern North American tree called hackberry or nettle tree is C. occidentalis. It has bright green elmlike leaves, which often have three prominent veins arising from the base of the blade and edible pea-sized purplish-black fruits attractive to birds. The bark is sometimes covered with wartlike bumps. It is often
*
Corresponding author. E-mail address: [email protected] (F. Demır).
planted as a street tree, attaining heights of from 12 to 30 m. Mississippi hackberry or sugarberry (C. laevigata) is a shorter tree native to moist soils of central North America. The Mediterranean hackberry or European nettle tree (C. australis) is an ornamental tree that has lance-shaped, gray-green leaves and larger edible fruits. Some West African species produce valuable timber (Anonymous, 2000; Bean, 1981; Chiej, 1984; Facciola, 1990; Huxley, 1992) The fruits are astringent, lenitive and stomachic (Chevallier, 1996; Chiej, 1984). The fruit, unripe fruit, is often considered to be very effective medicinally (Chevallier, 1996). A decoction of both leaves and fruit is used in the treatment of amenorrhea, heavy menstrual and intermenstrual bleeding and colic (Chopra, Nayar, & Chopra, 1986; Duke & Ayensu, 1985). The decoction can also be used to astringe the mucous membranes in the treatment of diarrhea, dysentery and peptic ulcers (Anonymous, 2001; Chevallier, 1996). Eighty species were found in the northern hemisphere and southern Africa. About 17 species are known in
0260-8774/02/$ - see front matter 2002 Elsevier Science Ltd. All rights reserved. PII: S 0 2 6 0 - 8 7 7 4 ( 0 1 ) 0 0 2 1 0 - 2
242
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Nomenclature D Dg L M Mc M1000 P Pb Pk q R
diameter of fruit (mm) geometric mean diameter (mm) length of fruit (mm) unit mass of fruit (g) moisture content (%) 1000 fruit mass (g) projected area ðmm2 Þ bulk density ðkg=m3 Þ fruit density ðkg=m3 Þ torque arm (cm) (10.5 cm) Correlation coefficient
horticulture. The pollen of some species is suspected to cause hayfever (Wodehouse, 1971). To optimum of threshing performance, processes of pneumatic conveying, storing and other processes of hackberry fruits, its physical properties must be known. No detailed study concerning nutritional and physical properties of hackberry fruits have been performed up to now. The purpose of this study is to determine the nutritional and physical properties of wild Turkish hackberry fruits.
R2 S Ta Tm V Vt W Ø e ls ld
Coefficient of determination surface area ðmm2 Þ beginning value of the torque (N cm) average value of the torque (N cm) volume of fruit ðmm3 Þ Terminal velocity (m/s) sample weight (10 N) sphericity porosity (%) static coefficient of friction dynamic coefficient of friction
cooled at 0 C for 1 h. The sample was prepared for mineral analysis and determined in a ICP–AES (Varian– Vista) see below (Skujins, 1998). Instrument RF power Plazma gas flow rate (Ar) Auxilary gas flow rate (Ar) Viewing height Copy and reading time Copy time
ICP–AES (Varian–Vista) 0.7–1.5 kW (1.2–1.3 kW for axial) 10.5–15 l/min (radial) 15 l/min (axial) 1.5 l/min 5–12 mm 1–5 s (max 60 s) 3 s (max 100 s)
2.2. Determination of physical properties 2. Materials and methods Ripe wet mature hackberry fruits were used for all the experiments in this study. The crop was harvested at Kastamonu (Tasßk€ opr€ u) during the summer season of 2000. Hackberry fruits were kept in cooled bags for transport to the laboratory. The fruits were cleaned in an air screen cleaner to remove all foreign matter such as dust, dirt, stones and chaff as well as immature and damaged fruits. The initial moisture content of fruits was determined by using a standard method (Brusewitz, 1975; USDA, 1970). The remaining material was packed in a 2000 ml hermetic glass vessel and kept in cold storage until use. Vessels were selected randomly from the chamber, and the required fruits were taken randomly from the vessels and dried down to the desired moisture content by the vacuum oven method (Baryeh, 2001; Joshi, Das, & Mukherjee, 1993; Singh & Goswami, 1996; Suthar & Das, 1996) before tests were conducted on them. The nutritional properties of the fruits were analyzed according to AOAC (1984). Results were analyzed for statistical significance by analysis of randomized plots of factorial experimental design (Minitab, 1991).
To establish the sizes and projected areas of fruits, 10% samples were randomly taken and their linear dimensions, i.e. length (L), diameter (D) and projected area (P) were measured. Projected area of a fruit was determined using a digital camera (Kodak DC 240) and Sigma Scan Pro5 program (Ayata, Yalcßın, & Kirisßßci, 1997; Trooien & Heermann, 1992). Linear dimensions were established by using a digital vernier caliper with a sensitivity of 0.01 mm. The mass of fruit was determined on 100 randomly selected fruits and converted to a 1000 fruits basis. Fruit unit mass (M) and 1000 fruit mass ðM1000 Þ were measured with an electronic balance of 0.001 g sensitivity. € zcan, Several investigators (Baryeh, 2001; Demir & O 2001; Dehspande, Bal, & Ojha, 1993; Dutta, Nema, & Bhardwaj, 1988; Joshi et al., 1993; Mohsenin, 1970; Shepherd & Bhardwaj, 1986; Singh & Goswami, 1996) have measured these dimensions for other grains and seeds in a similar manner to determine size and shape properties. The geometric mean diameter ðDg Þ of the fruit was calculated by using the following formula (Mohsenin, 1970):
2.1. Determination of nutritional properties
Dg ¼ ðLD2 Þ1=3 :
About 1 g ground hackberry fruit was put into a small glass bottle and 5 ppm of standard was added and
The fruit volume (V) and fruit density ðPk Þ, were determined as a function of moisture content using the liquid
ð1Þ
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
displacement method. Toluene ðC7 H8 Þ was used rather than water because it is absorbed by fruits to a lesser extent. Also its surface tension is low, so it fills even shallow dips in a fruit and its dissolving power is low € €t, 1998; Singh & Goswami, 1996; (Mohsenin, 1970; O gu Sitkei, 1976). According to Jain and Bal (1997) and Mohsenin (1986), the degree of sphericity (Ø) can be expressed as follows: Ø ¼ ðLD2 Þ
1=3
=L ¼ Dg =L:
ð2Þ
This equation was used to calculate the sphericity of the fruits in the investigation. The surface area (S) of the fruit was calculated by using the following formula (Mohsenin, 1970): S ¼ ðpD2 L2 Þ=6ð2L DÞ ¼ pD2g :
ð3Þ
The bulk density ðPb Þ was determined with a weight per hectoliter tester which was calibrated in kg per hectoliter (Dehspande et al., 1993; Jain & Bal, 1997; Suthar & Das, 1996). The fruits were filled into the calibrated bucket from a height of about 15 cm and excess fruits were removed by a strike off stick. The fruits were not compacted in any-way. The porosity ðeÞ was determined by the following equation: e ¼ 1 Pb =Pk ;
ð4Þ
in which Pb and Pk are the bulk density and the fruit density, respectively, (Mohsenin, 1970; Thompson & Isaacs, 1967). The terminal velocities (or critical velocities) of fruits at different moisture content were measured using an air column. For each test, a sample was dropped into the air stream from the top of the air column, through which air was blown upwards to suspend the fruits in the air stream. The air velocity near the location of the fruit
243
suspension was measured by electronic anemometer having a least count of 0.1 m/s (Hauhouout-O‘hara, Criner, Brusewitz, & Solie, 2000; Joshi et al., 1993; Mohsenin, 1986). The coefficient of friction of fruit was measured using a friction device modified by Tsang-Mui-Chung, Verma, and Wright (1984) and improved by Chung and Verma (1989). Also, both the static and dynamic coefficient of friction with an applied torque were measured and calculated using the equation (Chung & Verma, 1989): ls ¼ Ta =Wq;
ð5Þ
ld ¼ Tm =Wq;
ð6Þ
where ls equals static coefficient of friction, Ta equals beginning value of torque, ld equals dynamic coefficient of friction, Tm equals average value of the torque, q the length of torque arm, and W is the weight of fruits to calculate the dynamic and static coefficients of friction, the average value of the torque during the rotation of the disk and the maximum value of torque obtained as the disk started to rotate were used on the rotating surface.
3. Results and discussion 3.1. Nutritional properties The nutritional properties of hackberry fruits are given in Table 1. Crude oil, crude protein, crude fiber, crude energy and ash contents were found as 6.70%, 19.32%, 4.40%, 16.2 kcal/g and 15.29%, respectively. Also, Na, K, P, Mn, Ca, B, Ba, Ms and Se were established as major minerals in fruits. Some minerals such as Na, K, P, Ca, Mg, Mn and Zn of hackberry fruits were found to be higher compared with those of
Table 1 Nutritional properties of fruits Ash (%) Dry matter (%) Crude oil (%) Na (mg/kg) P (mg/kg) K (mg/kg) Fe (ppm) Zn (ppm) Mn (ppm) Ca (ppm) Ag (ppm) Al (ppm) As (ppm) B (ppm) Ba (ppm) Ti (ppm) V (ppm)
15.29 90.23 6.70 59.515 5.755 1519.59 31.1 3523.66 143.04 21.365 1.725 3.46 0.15 22.495 1.245 43973.09 251.11 2.587 0.267 18.63 1.43 12.88 1.35 64.4 1.56 264.42 5.63 1.145 0.125 0.845 0.005
Crude energy (kcal/g) Crude fiber (%) Crude protein (%) Bi (ppm) Co (ppm) Cd (ppm) Cr (ppm) Cu (ppm) Ga (ppm) In (ppm) Li (ppm) Mg (ppm) Ni (ppm) Pb (ppm) Se (ppm) Sr (ppm)
16.2 4.40 19.32 11.895 0.355 2.30 0.121 2.20 3.105 0.595 1.105 0.105 0.18 0.11 2.43 0.135 4.66 0.168 6732.5 69.93 1.275 0.125 4.17 0.147 18.28 0.315 234.615 7.115
244
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Table 2 Means and standard errors of fruit linear dimensions and linear dimensional dependent properties at different moisture content levels Fruit dimensions
15.25% w.b.
32.65% w.b.
50.42% w.b.
Diameter (D), mm Length (L), mm Volume (V), mm3 Geometric mean diameter (Dg ), mm Sphericity (Ø) Surface area (S), mm2
8.069 0.129 9.347 0.154 277.854 12.822 8.374 0.124 0.895 0.007 206.411 6.339
9.0964 0.093 10.2611 0.247 395.5629 13.464 9.3552 0.134 0.9119 0.009 260.7075 6.063
9.4702 0.272 10.7295 0.460 448.36 39.433 9.7534 0.296 0.9099 0.020 283.2485 16.793
The coefficients of correlation (Table 3) show that the D=L, D=V , D=Dg , D=Ø and D=S rations are highly significant. This indicates that the length, mass, volume, the geometric mean diameter, sphericity and surface area are closely related to the diameter of fruit. The relationship between the diameter (D) and other dimensions (M; V ; Dg ; Ø; S) for fruit can be represented by the following regression equation: D ¼ 3:41 0:00277M þ 0:00163V þ 0:906Dg þ 4:24Ø 0:00224S
Fig. 1. Frequency distribution curves of fruit dimensions at 15.25% m.c.w.b.
€ zcan, 2001; rosa and peanut (Baryeh, 2001; Demir & O € Ozcan & Akbulut, 1998). 3.2. Physical properties Table 2 shows the size distribution of the hackberry fruits. The frequency distribution curves (Fig. 1) for the mean values of the dimensions show a trend towards a normal distribution. About 83% of the fruits had a diameter ranging from 8.0 to 8.3 mm. The following general expression can be used to describe the relationship among the average dimensions of the fruits at 15.25% (w.b.) moisture content: D ¼ 0:863L ¼ 34:56M ¼ 0:029V ¼ 0:963Dg ¼ 9:007Ø ¼ 0:0390S:
ð7Þ
ðR2 ¼ 1Þ:
ð8Þ
The fruit (true) density of hackberry fruits at different moisture levels varied from 826.1 to 1105:9 kg=m3 (Fig. 2) and indicated an increase in fruit density with an increase in moisture content. The variations in fruit density with moisture content of hackberry fruit can be represented by the following correlations: Pk ¼ 704:93 þ 7:957Mc
ðR2 ¼ 1Þ:
ð9Þ
The values of the bulk density for fruits at different moisture levels varied from 595.1 to 535:9 kg=m3 (Fig. 3) and indicated a decrease in bulk density with an increase in moisture content. The bulk density ðPb Þ of fruit was found to have the following relationships with moisture content ðMc Þ: Pb ¼ 619:06 1:6815Mc
ðR2 ¼ 0:9904Þ:
ð10Þ
Since the porosity depends on the bulk as well as true or fruit densities, the magnitude of variation in porosity depends on these factors only. The porosity of hackberry fruit was found to increase with increase in moisture content from 15.25% to 50.42% w.b. as shown
Table 3 Correlation of fruit linear dimensions and linear dimensional dependent properties at 15.25% moisture content Particulars
Ratio
Degrees of freedom
Correlation coefficient ðR2 Þ
D=L D=V D=Dg D=Ø D=S
0.863 0.0290 0.963 9.007 0.0390
99 99 99 99 99
0.625 0.978 0.960 0.459 0.950
• Significant at 1% level. • D=L diameter/length, D=V diameter/volume, D=Dg diameter/geometric mean diameter. • D=Ø diameter/sphericity, D=S diameter surface area.
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
245
Fig. 2. Effect of moisture content on fruit density.
Fig. 5. Effect of moisture content on projected area.
Fig. 3. Effect of moisture content on bulk density.
Fig. 6. Effect of moisture content on terminal velocity.
Fig. 4. Effect of moisture content on porosity.
Fig. 7. Effect of moisture content on 1000 fruit mass.
in Fig. 4. The relationship between the porosity ðeÞ and moisture content ðMc Þ for fruit derived from the data was: e ¼ 21:806 þ 0:6498Mc
ðR2 ¼ 0:9876Þ:
ð11Þ
The form of the plot is similar to that for pigeon pea as found by Shepherd and Bhardwaj (1986). C ß armen (1996) reported a similar increase in porosity from 27.5% to 32.2% for lentil. The projected area of hackberry fruit (Fig. 5) increased by about 35.9%, while the moisture content of hackberry fruit increased from 15.25% to 50.42% w.b. Similar trends were reported for many other seeds (Mohsenin, 1970; Sitkei, 1986). Dehspande et al. (1993) found that the projected area of soybean grain increased from 0.813 to 0:952 cm2 , when the moisture content was increased from 6% to 26% d.b. The variation in pro-
jected area (P) with moisture content ðMc Þ of hackberry fruit can be represented by the following equation: P ¼ 47:718 þ 0:5599Mc
ðR2 ¼ 0:948Þ:
ð12Þ
The experimental results of the terminal velocity for the hackberry fruit at different moisture levels are plotted in Fig. 6. As moisture content increased, the terminal velocity was found to increase linearly. The results are similar to those reported by Kural and C ß arman (1997), but the values were higher than those for pumpkin seeds and cereals (Gorial & Callaghan, 1990; Joshi et al., 1993). The increase in terminal velocity with increase in moisture content can be attributed to the increase in mass of an individual fruit per unit frontal area presented to the air stream. The variation can be represented mathematically as:
246
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247
Fig. 8. Effect of moisture content on static coefficient of friction.
Fig. 9. Effect of moisture content on dynamic coefficient of friction.
Table 4 Relationships between friction coefficients and moisture content of hackberry fruit for various material surfaces
Galvanized steel Plywood Rubber
Vt ¼ 2:3975 þ 0:1631 Mc
Static
Dynamic
ls ¼ 0:2291 þ 0:0051 Mc R2 ¼ 0:9822 ls ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ls ¼ 0:3835 þ 0:0043 Mc R2 ¼ 0:999
ld ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ld ¼ 0:3315 þ 0:0048 Mc R2 ¼ 0:9909 ld ¼ 0:3835 þ 0:0043 Mc R2 ¼ 0:999
ðR2 ¼ 0:9915Þ:
ð13Þ
It can be seen from Fig. 7. that the 1000 fruit mass increases linearly with moisture content. A similar trend was reported Dehspande et al. (1993). The value of the 1000 fruit mass of hackberry at different moisture levels varied from 247.5 to 594 kg. The following linear relationship was fitted to the data: M1000 ¼ 105:2 þ 9:8475 Mc
ðR2 ¼ 0:994Þ:
The bulk density decreased from 595.1 to 535:9 kg=m3 and the fruit density increased from 826.1 to 1105:9 kg=m3 while the moisture content increased from 15.25% to 50.42% w.b. As increasing moisture content, porosity, projected area, terminal velocity, 1000 fruit mass, increased from 30.97 to 53.84%, from 54.91 to 74:63 mm2 , from 4.73 to 10.47 m/s, from 247.5 to 594 g.
ð14Þ
The static and dynamic coefficients of friction for hackberry fruit determined with respect to rubber, plywood and galvanized steel surfaces are represented in Figs. 8 and 9. At all moisture contents, both the static and dynamic coefficients of friction were greatest for hackberry fruits on rubber and least for galvanized steel, with plywood in between. As the moisture content of the fruit increased, the static and dynamic coefficients increased significantly. The relationship between the friction coefficients and moisture content of the fruit on the various surfaces is presented in (Table 4).
4. Conclusion At 15.25% m.c.w.b., the average diameter, length, unit mass, volume of fruit, the geometric diameter, sphericity and surface area of hackberry fruits were 8.07 mm, 9.34 mm, 0.233 g, 277:85 mm3 , 8.37 mm, 0.89 and 206:4 mm2 , respectively.
References Anonymous (2000). Available: http://www.britannica.com/. Anonymous (2001). Available: http://www.gardenbed.com/. AOAC. (1984). Officials methods of analysis. Association of Official Analytical Chemist (14th ed.). VA, USA: Arlington. Ayata, M., Yalcßın, M., & Kirisßßci, V. (1997). Evaluation of soiltine interaction by using image processing system. In National Symposium on Mechanisation in Agriculture (pp. 267–274). Turkey: Tokat. Baryeh, E. A. (2001). Physical properties of bambara groundnuts. Journal of Food Engineering, 47(4), 321–326. Baytop, T. (1994). The dictionary of plant in Turkey. Turkish Language Association. Publications No: 578, Ankara, Turkey (in Turkish). Bean, W. (1981). Trees and Shrubs Hardy in Great Britain. (Vols. 1–4 Suppl.). Murray. Brusewitz, G. H. (1975). Density of rewetted high moisture grains. Transactions of the ASAE, 18, 935–938. C ß armen, K. (1996). Some physical properties of lentil seeds. Journal of Agricultural Engineering Research, 63, 87–92. Chevallier, A. (1996). The encyclopedia of medicinal plants. London: Dorling Kindersley. Chiej, R. (1984). Encyclopaedia of medicinal plants. MacDonald.
F. Demır et al. / Journal of Food Engineering 54 (2002) 241–247 Chopra, R. N., Nayar, S. L., & Chopra, I. C. (1986). Glossary of Indian Medicinal Plants (Including the Supplement). Council of Scientific and Industrial Research, New Delhi. Chung, J. H., & Verma, L. R. (1989). Determination of friction coefficients of beans and peanuts. Transactions of the ASAE, 32, 745–750. Dehspande, S. D, Bal, S., & Ojha, T. P. (1993). Physical properties of soybean. Journal of Agricultural Engineering Research, 56, 89–98. € zcan, M. (2001). Chemical and technological properties Demir, F., & O of rose (Rosa canina L.) fruits grown wild in Turkey. Journal of Food Engineering, 47, 333–336. Duke, J. A., & Ayensu, E. S. (1985). Medicinal Plants of China Reference Publications. Dutta, S. K., Nema, V. K., & Bhardwaj, R. K. (1988). Physical properties of gram. Journal of Agricultural Engineering Research, 39, 259–268. Facciola, S. (1990). Cornucopia – a source book of edible plants. Kampong Publications. Gorial, B. Y., & Callaghan, J. R. (1990). Aerodynamic properties of grain/straw materials. Journal of Agricultural Engineering Research, 46, 275–290. Hauhouout-O‘hara, M., Criner, B. R., Brusewitz, G. H., & Solie, J. B. (2000). Selected physical characteristics and aerodynamic properties of cheat seed for seperation from wheat. The GIGR Journal of Scientific Research and Development, 2. Huxley, A. (1992). The new RHS dictionary of gardening. New York: MacMillan Press. Jain, R. K., & Bal, S. (1997). Physical properties of pearl millet. Journal of Agricultural Engineering Research, 66, 85–91. Joshi, D. C., Das, S. K., & Mukherjee, R. K. (1993). Physical properties of pumpkin seeds. Journal of Agricultural Engineering Research, 54, 219–229. Kural, H., & C ß arman, K. (1997). Aerodynamic properties of seed crops. In National symposium on mechanisation in agriculture (pp. 615–623). Turkey: Tokat. Minitab, C. (1991). Minitab reference manual (Release 7.1) Minitab Inc., State Coll., PA 16801, USA.
247
Mohsenin, N. N. (1970). Physical properties of plant and animal materials. New York: Gordon and Breach Science Publishers. Mohsenin, N. N. (1986). Physical properties of plants and animal materials (pp. 616–647). New York: Gordon and Breach Science Publishers. € gu €t, H. (1998). Some physical properties of white lupin. Journal of O Agricultural Engineering Research, 56, 273–277. € zcan, M., & Akbulut, M. (1998). Some physical and chemical O properties of myrtle (Myrtus communis L.) fruits. Gıda, 23, 121–123. Shepherd, H., & Bhardwaj, R. K. (1986). Moisture-dependent physical properties of pigeon pea. Journal of Agricultural Engineering Research, 35, 227–234. Singh, K. K., & Goswami, T. K. (1996). Physical properties of cumin seed. Journal of Agricultural Engineering Research, 64, 93–98. Sitkei, G. (1976). Mechanics of agricultural materials, Budapest, Akademia Kiado. Sitkei, G. (1986). Mechanics of agricultural materials. Budapest: Akademiai Kiado. Skujins, S. (1998). Handbook for ICP–AES (Varian–Vista). A short guide to vista series ICP–AES Operation. Varian Int. AG, Zug, Version 1.0, Switzerland. Suthar, S. H., & Das, S. K. (1996). Some physical properties of karingda seeds. Journal of Agricultural Engineering Research, 65, 15–22. Thompson, R. A., & Isaacs, G. W. (1967). Porosity determination of grains and seeds with air comparison pycnometer. Transactions of the ASAE, 10, 693–696. Trooien, T. P., & Heermann, D. F. (1992). Measurement and simulation of potato leaf area using image processing I, II, III. Transactions of the ASAE, 35(5), 1709–1722. Tsang-Mui-Chung, M., Verma, L. R., & Wright, M. E. (1984). A device for friction measurement of grains. Transaction of the ASAE, 27, 1938–1941. USDA, (1970). Official grain standards of the United States. US Department of Agricultural Consumer and Marketing Service Grain Division, (Revised). Wodehouse, R. P. (1971). Hayfewer plants (2nd rev.). New York: Hafner.