Transcript Document

Evaluation of Dextran in Sugar
Factories
Presented
WIRAT VANICHSRIRATANA
Department of Biotechnology, Faculty of Agro-Industries, Kasetsart University, Thailand
Research Parties
 Amano Enzyme Inc.
 Cinnamon Company Limited
 Kasetsart University
Outline
 Project Objectives
 Where is dextran
 Factory trial
 Dextran measurement
 Dextranase application
 Process improvement
 Cost analysis
 Conclusion
Objectives
 To evaluate the amount of dextran in cane mixed
juice and in product (raw syrup).
 To reduce dextran in the process.
 To publicize the obtained results and
methodologies to the Thai sugar factories.
Sugarcane in Thailand:
where dextran comes from
Sugarcane
Labors
Transports
Processing
Sugarcane in Thailand
 Sugarcane cultivation in Thailand for the year
2011/2012 was around 98 million tonnes.
Sugar cane harvesting
Sugarcane
Labors
Transports
Processing
Products
Sugar cane burning
 The shortage of labour for harvesting the
sugarcane was the main reason why the cane was
burnt before harvesting.
 In Thailand over 50% of the cane is burnt.
Sugar cane harvesting
Leuconostoc mesenteroides
n Sucrose
Leuconostoc mesenteroides
Dextran
+ Fructose
 the lactic acid bacterium which mainly
attacks the sucrose in the cane and
produces dextran.
Leuconostoc mesenteroides
Dextran
 The straight chain consists of α-1,6 glycosidic
linkages between glucose molecules, while
branches begin from α-1,3 linkages.
 The name dextran refers to a large family of
glucose polymers whose structures and
subsequent properties can vary widely.
This variation in structure poses a huge challenge for any analyst trying to detect the molecules
especially against a substantial background of saccharides with similar structures and properties
Sucrose
Crystals
Sucrose
Crystals
(dextran
contamination)
(without dextran
contamination)
Source: http://www.dextran.co.uk
Economic loss
“1
ppm of dextran in sugar juice”
results in
“a loss of 0.0011 kg of raw sugar / 1 ton of sugarcane”
At 2011/2012; sugarcane production in Thailand
around 98 Million tons, (1 ppm of dextran), results in
“Raw sugar lost of
98,000 kg”
How to reduce dextran:
Sugarcane
Labors
Transports
Processing
Products
Dextranase
 Dextranase is the enzyme that hydrolyses the α -1,6
linkages mainly present in the dextran structure and
is frequently used in the sugar factory to remove
dextran from juice where contamination exists.
Dextranase
(α-D-1,6 glucan-6-glucano hydrolase)
(EC 3.2.1.11)
Dextran
Glucose Chain
(α-1,6)
+
Dextranase
+
Fructose
Dextranase
Factory Trial
1. Factory A (yield 110 kg sugar/TC)
Milling Period: November-May
2.9 MT (Fresh 1.05 + Burnt 1.9)
2. Factory B (yield 101 kg sugar/TC)
Milling Period: November-May
1.9 MT (Fresh 0.3 + Burnt 1.7)
Factory Trial
Determination of dextran contamination
Factory A
Factory B
daily composite
samples
I. Mixed juice
II. Clarified juice
III. Raw syrup
IV. Final molasses
(For the period of 14 days)
Dextran Contamination
“Dextran ELISA Kit”
Determination of dextran contamination
1. Haze method
2. Eliza test kit
Determination of dextran contamination
Determination of dextran contamination
Dextran concentration at factories A and B
before the application of dextranase
4000
Dextran concentration (ppm)
Factory A
Factory B
3000
2000
1000
0
mixed juice
clarified juice
raw syrup
final molasses
The application of dextranase
Clarified Juice
Raw syrup
Evaporator Set (60-70 ˚C, pH 6-7)
Dextranase
Without dextranase
2 ppm of dextranase*
5 ppm of dextranase*
*mg/kg cane
Dextran Determination
Raw syrup
Final molasses
The application of dextranase
Temperature: 60-70 OC
CLARIFICATION
CLARIFIED JUICE
EVAPORATOR
RAW SYRUP TANK
The application of dextranase
Dextran content in raw syrup and final molasses from
factory A, before and after adding dextranase enzyme
Date
(D/M/Y)
18.04.12
19.04.12
20.04.12
21.04.12
22.04.12
23.04.12
25.04.12
26.04.12
27.04.12
29.04.12
01.05.12
03.05.12
05.05.12
07.05.12
09.05.12
11.05.12
Dextranase concentration
(mg/kg cane)
0 ppm
0 ppm
0 ppm
0 ppm
0 ppm
0 ppm
2 ppm
2 ppm
2 ppm
2 ppm
2 ppm
5 ppm
5 ppm
5 ppm
5 ppm
5 ppm
Dextran content (ppm)*
Raw syrup
Final molasses
520
1671
496
4765
3825
4392
331
5629
3919
3629
815
613
393
395
440
467
251
187
138
152
251
235
320
497
600
497
1478
1199
1644
Process improvement
 Dextran quantity depending on cane quality.
 Dextran causes sugar loss.
 High dextran also causes molasses purity to
increased
Parameters for Process improvement
 Yield of sugar per ton cane
 Purity of molasses
Purity and sugar yield in factory A, before and after
adding dextranase enzyme
120
Purity and sugar weight % cane
100
80
purity final molasses
60
sugar weight %cane 10 ccs
Linear (purity final molasses)
Linear (sugar weight %cane 10 ccs)
40
20
0
0
5
10
15
enzyme 27 April - 12 May
20
25
Purity and sugar yield in factory B, before and after
adding dextranase enzyme
140
120
Purity and Sugar wiegh % cane
100
80
purity final molasses
sugar weight %cane 10 ccs
60
Linear (purity final molasses)
Linear (sugar weight %cane 10 ccs)
40
20
0
0
5
10
15
enzyme 25 April - 11 May
20
25
Cost Analysis
Process
Enzyme
Production Improvement
Sugarcane
“High Income”

The application of dextranase enzyme to reduce dextran content in
sugar mill process streams and to demonstrate the effective level of
enzyme.
Sugar yield in factory A, before and after adding
dextranase enzyme
Factory A
120
Yield sugar/ton cane
100
80
82
88
60
40
20
0
0
5
10
15
Day
20
25
Cost Analysis (Factory A)
(Approximation based on estimating yield)
1. Cane crushing during the application of enzyme: 159,900 tons
2. Amount of enzyme dextranase: 500 litres ($35,000)
(@$70 /litre)
3. Yield sugar before application of enzyme: 82 kg/TC (13,110 TS)
4. Yield sugar after application of enzyme: 88 kg/TC (14,070 TS)
5. Increase in sugar: 960 TS ($528,000)
(@550 $/TS)
6. Profit gain: $493,000 ($3.1 /TC)
Sugar yield in factory B, before and after adding
dextranase enzyme
Factory B
Yield 96Pol, 10CCS
100.00
84.8
82.37
80.00
60.00
40.00
20.00
1/4/2555
6/4/2555 11/4/2555 16/4/2555 21/4/2555
29/4/2555 4/5/2555
9/5/2555
Cost Analysis (Factory B)
(Approximation based on estimating yield)
1. Cane crushing during the application of enzyme: 112,000 tons
2. Amount of enzyme dextranase: 300 litres ($21,000)
(@70 $/litre)
3. Yield sugar before application of enzyme: 82.5 kg/TC (9,240
TS)
4. Yield sugar after application of enzyme: 84 kg/TC (9,408 TS)
5. Increase in sugar: 168 TS ($92,400)
(@550 $/TS)
6. Profit gain: $71,400 ($0.64 /TC)
Conclusion
 Dextran formation associated with the processing of a high
portion of burnt sugarcane and long delay times before milling.
 Dextranase is an effective and practical way to reduce the
dextran contamination in the milling processes. Dextranase L
“Amano” was used to reduce dextran in the process.
 The suitable dosing point was at the 4th -5th effect of the
evaporator.
 Temperature was at 60-70OC, pH was around 5.9 to 6.1 and
Retention time was around 30 minutes.
Conclusion
 The suggested enzyme dosage was in the range of 2-5 ppm.
 Based on sugar yield calculation, profit gain of $0.6 - $3 per ton
cane can be obtained due to higher sugar recovery.
 Further test and analysis may be needed to confirmed the
enzyme benefit and determine the return of investment to the
sugar factories.
Research publication
THAILAND SUGAR SEMINAR 2012
“Technology for improving sugar process efficiency ”
October, 5 2012
Royal Hill Golf Resort and Spa
Nakhon Nayok
Acknowledgment
The authors are grateful to the Amano Enzyme for the financial funding
of this research.
Department of Biotechnology, Faculty of agro-industry
Kasetsart University, Thailand