27 temperature 180˚C. the sample cannot dry properly and it stuck in the wall and result the higher
of moisture content.
2.2 Total Polyphenols Content
The Folin-Ciocalteu assay is one ofthe oldest methods developed to determine the content of total poliphenols. The total polyphenols of green tea powder variated from 27.27-30.69 ww
db. The highest total polyphenols content was found in tea powder with treatment 6 solid concentration in feed
and inlet air temperature 180˚C about 30.69 ± 0.17 ww db and the lowest polyphenol content was found in tea powder with treatment 3 solid concentration in
feed and inlet air temperature 220˚C about 27.27 ± 0.04 ww db.
An increase inlet temperature 180- 220˚C decrease polyphenols content and increase feed
concentration not affects and results variated amount of total polyphenols. Another research reported a slight decrease in total polyphenols content of the spray dried soybean extract by
increasing the inlet air temperature Georgetti et al., 2008.
2.3 Antioxidant Activity
Antioxidant activity DPPH free radical scavenging activity was determined with DPPH scavenging activity. The DPPH 2,2-diphenyl-1picrylhydrazyl system offers a stable radical-
generating procedure. It is sensitive enough to detect active principles at low concentrations. Antioxidant activity of green tea powder variated from 218.80 - 247.77 mmol Trolox100 g db.
The highest antioxidant activity was found in tea powder with treatment 6 solid concentration in feed
and inlet air temperature 180˚C about 247.77 ± 5.65 mmol Trolox100 g db and the lowest polyphenol content was found in tea powder with treatment 3 solid concentration in
feed and inlet air temperature 220˚C about 218.80 ± 0.98 mmol Trolox100 g db.
An increase inlet temperature 180- 220˚C decrease antioxidant activity slightly, but an
increase feed concentration , it will increase antioxidant activity. Based on the results, the highest antioxidant activities of green tea powder 247.77 ± 5.65 mmol Trolox100 g db due to
the high content of total polyphenols compounds 30.69 ± 0.17 ww db as well as. It similar with another research that reported the total antioxidant activity of the samples can be
substantially associated with the phenolic substances present in the mountain tea spray dried. There was a significant positive correlation P 0.0001 and r
2
0.98239 between the results of the Total polyphenols and antioxidant activity of the samples Nadeem et al, 2011.
2.4 Catechins and Caffeine g100g db Content of Green Tea Powder
The Catechins of green tea powder variated significantly from 19.28-23.23 g100 g db and the caffeine is not different significantly 4.96-5.64 g100 g db. The highest total catechins
was found in tea powder with treatment 3 solid concentration in feed and inlet air temperature 220˚C and the lowest total catechins was found in tea powder with treatment 6 solid
concentration in feed and inlet air temperature 200˚C. The highest caffeine was found in tea
powder with treatment 3 solid concentration in feed and inlet air temperature 220˚C and the
lowest total catechins was found in tea powder with treatment 6 solid concentration in feed and inlet air temperature 180˚C. An increase inlet temperature and feed concentration results variated
amount of cathechins and not influences significantly to caffeine content. The catechins compound such as GC, EGC, C, EGCG, GCG, and ECG shown in Table 9.
The results shown EGC and EGCG are the higher catechin compound in the powder. The EGC
28 content of green tea powder variated significantly from 5.86-7.37 g100g db with treatment 3
solid concentration in feed and inlet air temperature 220˚C and the lowest total catechins was
found in tea powder with treatment 9 solid concentration in feed and inlet air temperature 220˚C. The EGCG content of green tea powder variated significantly from 4.62-7.02g100g db
with treatment 3 solid concentration in feed and inlet air temperature 220˚C and the lowest
total catechins was found in tea powder with treatment 6 solid concentration in feed and inlet air temperature 200˚C.
Table 9. Catechins and caffeine content g100g db of green tea powder Catechins
and Caffeine
compound Tea Powder with difference Concentration and Inlet Temp. ˚C
3 6
9 180˚C
200˚C 220˚C
180˚C 200˚C
220˚C 180˚C
200˚C 220˚C
Catechins GC
2.70 ±
0.11
c.d
2.54 ±
0.06
d
2.99 ± 0.23
a.b
2.82 ±
0.08
a.b.c.d
2.82 ±
0.10
a.b.c.d
3.09 ± 0.02
a
2.87 ±
0.05
a.b.c
2.75 ±
0.18
b.c.d
3.06 ±
0.05
a
EGC 6.89
± 0.22
a.b
6.67 ±
0.06
a.b
7.37 ± 0.76
a
6.68 ±
0.04
a.b
6.47 ±
0.25
a.b
6.17 ± 0.18
a.b
7.53 ±
1.41
a
7.04 ±
0.22
a.b
5.86 ±
0.13
b
C 1.32
± 0.01
c.d
1.25 ±
0.05
d
1.34 ± 0.13
c.d
1.40 ±
0.15
c.d
1.43 ±
0.04
b.c.d
1.48 ± 0.07
a.b.c
1.59 ±
0.03
a.b
1.59 ±
0.07
a.b
1.64 ±
0.00
a
EC 1.77
± 0.01
b
1.66 ±
0.08
b
1.83 ± 0.18
a.b
1.74 ±
0.04
b
1.75 ±
0.04
b
1.73 ± 0.06
b
1.99 ±
0.14
a.b
1.87 ±
0.03
a.b
2.38 ±
0.67
a
EGCG 6.49
± 0.11
a.b
6.52 ±
0.06
a.b
7.02 ± 0.73
a
5.62 ±
0.32
b.c
4.62 ±
0.74
c
5.43 ± 0.18
b.c
5.89 ±
0.96
a.b
7.06 ±
0.25
a
5.71 ±
0.08
b.c
GCG 1.61
± 0.02
1.53 ±
0.07
a
1.64 ± 0.18
a
1.60 ±
0.14
a
1.45 ±
0.17
a
1.61 ± 0.01
a
1.46 ±
0.18
a
1.58 ±
0.11
a
1.41 ±
0.06
a
ECG 1.02
± 0.01
a.b
0.99 ±
0.05
a.b
1.06 ± 0.08
a
0.86 ±
0.05
a.b
0.74 ±
0.15
b
0.93 ± 0.02
a.b
0.91 ±
0.30
a.b
1.10 ±
0.03
a
1.05 ±
0.03
a
Caffeine 5.37
± 0.04
a
5.09 ±
0.25
a
5.64 ± 0.47
a
4.96 ±
0.52
a
5.02 ±
0.37
a
5.37 ± 0.16
a
5.16 ±
0.61
a
5.63 ±
0.24
a
5.37 ±
0.18
a
Total of
Catechins 21.77 ±
0.45
a.b.c.d
21.14 ± 0.42
a.b.c.d
23.23 ± 2.28
a
20.69 ± 0.81
b.c.d
19.28 ± 1.49
d
20.43 ± 0.21
c.d
22.24 ± 0.09
a.b.c
22.97 ± 0.88
a.b
20.60 ± 0.05
b.c.d 1
Values are mean ± SD n=2
2
Value within a row with different letters are not significant differentp0.05 The GC content of green tea powder variated significantly from 2.54-3.09 g100g db with
treatment 6 solid and inlet air temperature 220˚C and the lowest total catechins was found in
tea powder with treatment 3 solid and inlet air temperature 200˚C. The EC content of green
tea powder variated significantly from 1.73-2.38g100g db with treatment 9 solid and inlet air temperature 220˚C and the lowest total catechins was found in tea powder with treatment 6
solid and inlet air temperature 220˚C. The C content of green tea powder variated significantly
from 1.25-1.64g100g db with treatment 9 solid and inlet air temperature 220˚C and the lowest
total catechins was found in tea powder with treatment 3 solid and inlet air temperature 200˚C.
The GCG content of green tea powder variated significantly from 1.41-1.64g100g db with treatment 3 solid
and inlet air temperature 220˚C and the lowest total catechins was found in tea powder with treatment 9 solid
and inlet air temperature 200˚C. The ECG content of green tea powder variated significantly from 0.74-1.10g100g db with treatment 9 solid and inlet air
temperature 220˚C and the lowest total catechins was found in tea powder with treatment 3 solid
and inlet air temperature 200˚C.
29
2.5. Correlation coefficients r and determination coeffisien r
