الفهرس 
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Abstract
Summary and conclusion
Two field experiments were carried out . The first was held in
Salcha Res . St . at Kafer El Sheikh Governorate, Egypt during 1996 -
1997 season to evaluate four varieties of sweet sorghum ”sorghum
biclor(L.) Moench” ( Honey, Dale, MN 1383 and NlN 4512) for yield
components , physical properties and chemical composition of juice and
syrup produced from the studied varieties to determine the possibility of
replacing this syrup with that of sugar cane .
Sweet sorghum yield is considered the third of sugar crops. Using
sweet sorghum in syrup production leads to save the sugar crop to the
sugar production . This leads to close the vast gab resulted from the
increase of sugar consumption. Therefore, this investigation was carried
out to study the differences between sorghum varieties syrup and cane
syrup cultivars.
The juice was extracted and clarified using different
concentrations of bentonite (0.5, 1.0, 1.5 and 2.0 g /L juice) and 15 g
diatomite earth . These concentrations were used with raw juice without
any treatment and juice treated with heating to the boiling point with
removing the foam on the surface to determine the optimum conditions
for juice clarification ; bentonite and diatomite earth concentration, pH
value temperature and contact time . Also , colouring matters removed
from produced syrup were evaluated by using the optimum conditions of
juice clarification and comparing it with the syrup produced from raw
JUlce .
The second experiment was carried out in Mallawi Res . St . , EI
Minia Governorate, Egypt during 1997 - 1998 season to evalute the new
cultivars of sugar cane (G. 85137F 153 and G. 84/70) to use them in
”black syrup” production. Also, comparing it with syrup produced from
”G.T. 54/9” commercial cultivar for yield, yield components, physical
properties ,chemical composition, quality criteria and sensory evalution
of extracted juice and syrup produced from cultivars under study
compared with commercial cane syrup.
Sweet sorghum varieties and sugar cane cultivars were planted and
treated according to the traditional agricultural practices of the region.
After extracting juice by using electric three roller horizontal mills, it
was concentrated by using direct flame untill it reached a concentration
of 75 % for produced syrup .
The rusults obtained in this study can be summarized as
follow:
1_Yield and yield components of sweet sorghum varieties:
Regarding the properties yield of gross stalks, yield of stripped
stalks, juice yield and scum yield , the lowest values were at ”Dale”
variety being 21.969, 12.427,6.057 and 0.350 ton/fed, while the highest
values were at ” MN 4512’~ variety being 37.450,27.300, 16.781 and
0.660 ton Ifed, respectively.
Concerning the forage yield and juice extraction percentage the
lowest values were at ” MN 1383” variety being 8.321 ton Ifed and
40.160 ,while the highest values were in ” MN 4512” variety being
10.150 ton Ifed , and 61.470 , respectively.
As for as bagasse yield and syrup yield, the lowest values were in
”Dale” variety being 6.370 and 0.952 ton Ifed ,while the highest values
were in ”Honey” variety being 12.202 and 2.518 ton I fed, respectively.
For syrup yield ton per ton of gross stalks and syrup extraction
percentage, the lowest values were in” MN 1383” variety being 0.043
ton I ton and 6.652, while the highest values were in ”Honey” variety
being 0.072 ton I ton and 10.107, respectively. For the scum extraction
percentage , ”Honey” variety had the lowest value being 1.726 and ”MN
1383” variety had the highest value being 3.189 .
11_ Yield and yield component of sugar cane cultivars:
Concerning yield of gross stalks , yield of stripped stalks ,forage
yield ,juice yield ,bagasse yield , syrup yield and scum yield, the lowest
values were in ”FI53” cultivar being 44.200,34.000, 10.200 ,..23.569,
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10.200, 4.034 and 0.347 ton / fed ,while the highest values were in” 0 .
84170” cultivar being 74.443,55.972, 18.471 ,40.048 , 15.924,6.332
and 0.593 ton / fed, respectively.
However , for syrup yield ( ton per ton of grorss stalks) , ”0
84170” cultivar had the lowest value being 0.085 ton / ton of gross stalks
,while” F 153” cultivar had the highest value being 0.091 toni ton of
grorss stalks.
Regarding juice extraction percentage and scum extraction
percentage, the lowest values were in” G.85/37” cultivar being 69.055
and 0.99 , while the highest values were in ”G.84/70” being 71.550 and
1.059 , respectively.
For syrup extraction percentage ,the lowest value was in ”
G.85/37” cultivar being 11.312 and the highest value was in” F153”
cultivar reaching 11.86 .
111_ Physical properties of optimum clarified raw juice and
syrup of sweet sorghum varieties:
A- Juice
The specific gravity , colour ,pH value and non - sucrose
substances % of the juice decreased after juice optimum clarification,
while there was an increase in the purity .
The lowest values of specific gravity were in”~ 1383” being
1.093 and 1.081,while the highest values were in” Honey” variety being
1.124 and 1.114 ,in raw and clarified juice ,respectively.
Concerning colour the lowest values were in ” Dale” and ”Honey”
varieties being 2.711 and 1.490, while the highest values were in ”~
1383” and ”Dale” varieties being 2.730 and 1.560, for raw and clarified
juice , respectively .
Regarding the pH value, the lowest values were at” MN1383”
variety being 4.81 and 4.89, while the highest values were at” Honey”
variety being 5.33 and 5.41 ,for raw and clarifiedjuice, respectively.
As for as the non - sucrose substances percentage, the lowest
values were in ”MN 1383” variety being 6.322 and 4.710 ,while the
highest values were at ”Honey” variety being 7.297 and 6.612 for raw
and clarified juice, respectively .
For the purity, the lowest values were at ”:MN 1383” variety being
54.843 and 62.320% , while the highest values were at ”Honey”variety
being 62.579and 65.200% for raw and clarified juice, resectively .
B) Syrup:
The specific gravity, colour, viscosity at 29°C and non - sucrose
substances’ze decreased after juice optimum clarification (turned later
into syrup ) , while there was an increase in the viscosity at 5 °C , pH
value and purity .
Concerning the specific gravity, the lowest values were at
”Honey” variety being 1.407 and 1.399 .while the highest values were at
”MN 1383” variety being 1.430 and 1.421 for raw and clarified syrup,
respectively. As for as the colour, the lowest values were at ”MN 4512”
and ” Honey” varieties being 2.318 and 1.972 , while the highest values
were at ”MN 1383” variety being 2.615 and 2.297 , for raw and clarified
syrup, respectively .
Regarding viscosity at 29°C, the lowest values were at ”MN 4512”
variety being 714.50 and 500 (C.P) ,while the highest values were at
”tvrn 1383” variety being 7799 .75 and 7500 (C.P) , for raw and clarified
syrup , respectively . Concerning the non - sucrose substances % the
lowest values were 48.590 and 43.237 in ”Honey” variety, while the
highest values were at ”MN 1383” variety being 50.307 and 44.296, for
raw and clarified syrup.
For viscosity at 5°C, the lowest values were 4770.75 and 4912.00
(C.P) ,while the highest values were 18937.50 and 17255.00 (C.P) at
”MN 1383” and ’’MN 4512” varieties for raw and clarified syrup ,
respectively .
As for as pH value, ”MN 1383” had the lowest values being 4.46
and 4.59, while the highest values were 4.99 and 5.12 in ’’Honey’’ variety
for raw and clarified syrup, respectively .
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Regarding purity percentage , the lowest values were 32.924 and
40.939 , while the highest values were 35.213 and 42.315 at ”MN1383”
and ~’Honey” varieties for raw and clarified syrup respectively.
IV- physical properties of the juice and syrup extracted from
sugar cane cultivars :
A) Juice:
Concerning colour , the lowest value was in ”G.T. 54 1 9” being
1.415, while the highest value was in” G. 84/70 ” cultivar being 1.775 .
The lowest value of pH was in” G.84 170” cultivar being 4.80,while the
highest value was in ”G.T. 54/9” being 5.39.
Regarding purity, the lowest value was in ”G.T. 54/9” being
80.6140/0, while the highest value was in ” F153 ” cultivar being
80.9020/0.For non - sucrose substances percentage the lowest value was
in ”G.T.54/9” cultivar being 4.071 ,while the highest value was in” F
153” cultivar being 4.106 .
B) Syrup produced in the laboratory from cultivars of sugar cane
compared with commercial cane syrup ( Treacle) :
Concerning specific gravity the lowest value was in ” Treacle”
being 1.353 and the highest value was in ” G. 84170” cultivar being
1.393,while the lowest value of colour was in ” G. 85/37” cultivar
being 1.388 and the highest value was in” Treacle” being 1.543.
As for as viscosity at 5 °C ,the lowest value was in ” Treacle”
being 925 (C.P) and the highest value was in ”G. 85 /37” cultivar being
3361.16 (C.P) , while the lowest value of pH was in” Treacle” being
4.4l.and the highest value was in” G.T. 54/9” being 4.99 .
For purity, the lowest value was in ”Treacle” being 50.468 %,
and the highest value was in” F 153” cultivar being 63.605% ,while the
lowest value for the non - sucrose substances was in” F153” being
27.296% and the highest value was in ”Treacle” being 34.920 % .
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v- Chemical composition of raw ,clarified juice and syrup of
sweet sorghum varieties:
While moisture, sucrose and total sugars increased ,total solids,
reducing sugars ,starch, total nitrogen , ash and titratable acidity
decreased.
A) Juice:
Regarding moisture, the lowest values were in ”Honey” variety
being 79.027 and 80.300 % , while the highest were in ”1\1N 1383”
variety 85.063 and 86.5900/0for raw, clarified juice, respectively.
For sucrose, the lowest values were in ”MN 1383” variety being
7.678 and 7.790%, while the highest were in ’’Honey’’ variety 12.203%
and 12.388%. Also for total sugars content, the lowest values were in
”1\1N 1383” variety being 9.670 and 9.750% , while the highest values
were 14.650 and 14.820 % in ”Honey” variety for raw, clarified juice ,
respectively .
Concerning total solids the lowest values were 14.938 and
13.410% in ”J\.1N 1383” variety, while the highest values were in
”Honey” being 20.972 and 19.700% . For reducing sugars, the lowest
values were 1.502 and 1.460 % in ”Dale” variety ,while the highest
values were In ”Honey” variety being 1.80S and 1.780% for raw,
clarified juice, respectively.
As for as starch content, the lowest were 0.663 and 0.610 % in
”Honey” variety, while the highest values were in ”MN 1383” being
0.970 and 0.933 % . For total nitrogen content, the lowest values were
0.482 and 0.450% in ”Dale” variety, while the highest values were in
”MN 4512” variety being 0.680 and 0.650% for raw ,clarified juice
respectively.
Concerning ash ,the lowest values were in ”Honey” variety. being
0.510 and 0.577 % ,while the highest values were in” MN 4512” variety
being 0.780 and 0.733% . Also for titratable acidity the lowest values
were in ”Honey” being 3.S8 and 3.40 mI. NaOH 0.1 N 110 gjuice ,while
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the highest values were in ” MN 1383” being 4.32 and 4.20 ml .
NaOHO.l Nil 0 g juice for raw, clarified juice respectively.
B) Syrup:
Concerning moisture , the lowest values were in ” Dale” and
”Honey” being 22.330 and 22.330/0 ,while the highest were in
”MNI383” and ” MN 4512” being 24.033 and 24.150% for raw and
clarified syrup , respectively.
For sucrose, the lowest values were in ”MN 1383” being 24.693
and 30.704 % , while the highest were in ” Honey” being 26.410 and
31.763% for raw and clarified syrup, respectively .
Also for total sugars content the lowest value was in” MN 1383”
being 56.895 and 59.180% , but the highest were in ”MN 4512” and ”
Honey” being 59.302 and 61.438% for raw and clarified syrup
respectively .
Regarding total solids ,the lowest values were in ”MN 1383” and
”MN4512” being 75.969 and 75.850% ,while the highest values were in
”Dale” and ” Honey” being 77.505 and 77.670 0/0.
For reducing sugars, the lowest values were in” :MN1383” being
30.902 and 26.860% ,but the highest values were in” MN 4512” and
”Honey” being 32.032 and 28.003% . As for as starch, the lowest values
were in ”Honey” being 0.304 and 0.280%, but the highest values were in
” MN1383” being 0.463 and 0.451% .For total nitrogen content the
lowest were in ”Dale” being 0.338 and 0.314%, while the highest
values were in ” MN 4512” being 0.530 and 0.445% .
Although the lowest values for ash were in ”Honey” being 2.092
and 1.980% , the highest values were in” MN1383” being 2.960 and
2.8400/0 . Also for titratable acidity, the lowest values were in ” Honey”
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being 16.78 and 15.37 ml. NaOH 0.1 N 110 g syrup,while the highest
values were in ”:MN1383” being 20.39 and 19.30 ml. NaOH 0.1 N 110 g
.syrup, for raw and clarified syrup, respectively.
VI - Chemical composition of thejuice and syrup extracted
from studied sugar cane cultivars and samples of
commercial cane syrup:
A) Juice:
It was noticed that” F 153” cultivar recorded the lowest vlaue of
moisture (77.800%) ,while ”G. 85/37 ” cultivar had the highest value (
78.738%) . In contrast, the lowest value of total solids was found in
”G.85/37” cultivar (21.263%), while the highest value was found in ” F
153” cultivar ( 22.200%). Also.the lowest value of sucrose was observed
in ” G. 84/70) cultivar ( 16.416%) and the highest value was found in
”F153” cultivar (17.394%).
Regarding the reducing sugars and starch , the lowest values
(0.550 and 0.193% ) were recorded in” G.T. S4 19” cultivar, while the
highest values (0.658 and 0.267% ) were found in ” G. 84/70” cultivar.
The lowest value of total sugars content was recorded in ”G.85/37”
cultivar ( 17.9300/0) ,while the highest value was observed in ”F153”
cultivar ( 18.8750/0) . As to total nitrogen, the lowest value was in” G .
85 I 37” cultivar (0.270%) and the highest value was found in ”G. 84/
70” cultivar (0.360%).
With regard to ash ,”F 153” cultivar had the lowest value
(0.350%) while” G .84/70” cultivar had the highest value (0.550%) .
, The titratable acidity ranged between ( 1.600 ) ml, NaOH 0.1 N in
”G.T.54/9” cultivar and (1.900) ml. Na OH 0.1 N in ”G. 85/37” cultivar.
B) Syrup:
The results confirm that” G.T.54 /9” cultivar had the lowest value
of moisture ( 22.140 % ), while ” G .841 70” cultivar had the highest
value (23.038 %). The results also indicate that the lowest value of total
solids was observed in ” G . 84 1 70” cultivar ( 76. 963%) ,while the
highest value was found in ”G.T. 54/9” cultivar ( 77.860%).
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Concerning sucrose, the lowest value (35.580%) was found in
”treacle” ,while the highest value ( 47.704%) was found in ”F 153”
cultivar . In contrast, ”F 153” cultivar had the lowest values of reducing
sugars and ash 18.535 and 0.860 % ,while ”Treacle” had the highest
values 28.152 and 2.373%) ,respectively . Also, the lowest value of
starch was recorded in” G.T. 54/9” cultivar ( 0.0100/0) but the highest
value was found in ” treacle” cultivar ( 0.0600/0) .
With regard to the total sugars , ”treacle” had the lowest value
(65.705% ) ,while” G. 85/37” cultivar had the highest value (70.0400/0).
It was noticed that nitrogen varied from ( 0.1850/0) for” G.85/37”
cultivar to ( 0.260%) for” treacle” cultivar . In addition, the titratable
acidity lowest value ( 8.17) mi. NaOH 0.1 N was recorded in ”G.T.54/9”
cultivar ,while the highest value ( 14.07) ml. NaOH 0.1 N was found in
”treacle” .
VII-Minerals content of perpared sweet sorghum varieties
syrup and cane cultivars syrup with commercial treacle:
A) Sweet sorghum varieties syrup:
The resutls confirm that the lowest value of potassium (14460
P.P.m) was recorded in ”MN 1383” variety, while the highest value
(45320.0 P.P.m) was found in” MN 4512” variety. ”MN 1383” had the
lowest value of sodium (1550 P.P.m) and” Dale” vareity had the highest
value (2450 P.P.m ). In contrast, ” Dale” variety had the lowest value of
Magnesium ( 2050 P.P.m) ,while” MN 1383” variety had the highest
value (2710 P.P.m).
Regarding iron and copper , the lowest values ( 150 and
3.50P.P.m) were observed in ”Honey” variety, while the highest values
( 170 and 5.5P.P.m) were found in” MN 1383” variety, respectively.
However ”MNI383” variety had the lowest value of phosphorous (280
P.P. m ),while ”Honey” variety had the highest value ( 490 P.P. m ) .
B) Cane syrup coltivars with commercial treacle:
Concerning potassium and phosphorous, ”F 153” cultivar had the
lowest values (5510 and 54.63 P.P.m), while ”G. 85/37” cultivar had
the highest values (17400and 70.41P.P.m), respectively .In addition,
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”G.85/37” cultivar had the lowest values of sodium and copper ( 460 and
2.5 P.P.m ,while ”Treacle” had the highest values ( 490 and 4.5 P.P.m),
respectively .
It was evident that magnesium ranged between ( 240 P.Pm) in
”G.T. 54/9” cultivar and ( 260 P.P.m ) in” G . 85 137” cultivar .
As to iron , the lowest value ( 70.P.P.m ) was recorded in
”Treacle” cultivar while the highest value ( 80 P.P .m) was found in
”F 153” cultivar .
VIII-Quality criteria of cane and sweet sorghum syrup:
A) Sweet soghum varieties syrup:
It was evident that” MN1383” variety had the lowest value of
total sugarsl total soluble solids % (78.907) , while” Honey” variety had
the highest value ( 81.917) . The lowest value of reducing sugars% 1total
sugars ( 45.387) was recorded in ” MN1383” variety and the highest
value ( 45 . 748 ) was found in ”MN 4512” variety. In addition, the
lowest value of sucrose % 1 total sugars ( 51.540) was found in
”MN4512” variety, while the highest value ( 51.882 ) was observed in ”
MN 1383” variety. With regard to sucrose 1 reducing sugars ratio, the
lowest value ( 1.127) was found in” MN 4512” variety ,while the highest
value ( 1.143) was found in ” MN 1383 ”variety .
As to reducing sugars 1 ash ratio, ”MNI383” variety had the
lowest value ( 9.458) and ” Honey” variety had the highest value
(14.143) .
B) Sugar cane cultivars syrup :
The results confmn that” G. 84/70” cultivar had the lowest value
of total sugars 1total soluble solids % ( 89.533) , while” treacle” had the
highest value ( 93.7Z1) .
Reducing sugars % 1total sugars varied from (28.344) for ”G.841
70) cultivar to ( 42.911 )for ”Treacle” cultivar .
Concerning sucrose % 1total sugars and sucrose 1rducing sugars,
”Treacle” had the lowest values (54.234 and 1.264 ) ,while” F 153”
cultivar had the highest values (69.388 and 2.574 ) . As to reducing
sugars 1 ash , the lowest value ( 11.814) was recorded in ”G. T. 54/9”
cultivar ,while the highest value (21.552) was found in” F153” cultivar .
..
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IX-Clarification of juice :
The heating process gave higher decolourization than the sweet
sorghum juice without heating . The optimum conditions for using
bentonite in clarification of raw sweet sorghum varieties juice were as
follows:
A- Optimum concentrations of bentonite were 1.5 , 1.0 , 1.5 and
2.0 g / liter juice for” Honey” ,” Dale ”” l\1N1383” and ”MN 4512”
varieties , respectively .
B- Optimum pH value of raw juice before treatment with bentonite
was 3 with all varieties .
C- Optimum temperature of raw juice in the clarification process
was 55°C for all sweet sorghum juice varieties.
D- Optimum contact time between bentonite and raw juice was 15
minutes for ” ~ 4512” variety and 20 minutes for the other three
varieties.
X-Sensory evaluations:
A)The sensory evaluation of sweet sorghum varieties syrup produced
from clarified juice compared with raw juice:
1-The best variety of taste , odour, consistancy and colour was
”Honey” variety , while the best variety in purity was ” MN 4512”
variety . However , the syrup produced from raw juice had the least
quality.
2- The best variety of all acceptabilty was in ” Honey” ( 86.1 ). It
has exhibited excellent for syrup ,it has mild sorghum floavor , amber
colour , and excellent quality . Consequently ”Honey” is recommended
for syrup production in Egypt.
B) The sensory evaluation of sugar cane cultivars syrup compared
with commercial ( Treacle) :
1- The best cultivar of taste and purity was” G. 84/70”, while
”G.T.54/9” was the best cultivar of odour ,consistancy and colour .
However, commercial treacle comes after them.
2- The best cultivars of all acceptability were” G.T.54/9” (86.2
degree) and commercial treacle (78.3 degree) .