F
t
=
C M M M
M M M M
Ft
´ ´ ´
´ ´ ´ ´
2
4
6
1
3
5
9
100
where
C
Ft
=mg fructose/kg diluted solution assayA
2
.
Mal
2
=
C M M M
M M M M
Mal2
´ ´ ´
´ ´ ´ ´
2
4
6
1
3
5
9
100
where
C
Mal2
=mgmaltitol/kg diluted solution assayA
2
.
Gal
2
=
C M M M
M M M M
Gal2
´ ´ ´
´ ´ ´ ´
2
4
6
1
3
5
9
100
where
C
Gal2
=mg galactose/kg diluted solution assayA
2
.
Calculateglucose related fructans(
G
i
)and fructose released from
fructans (
F
i
) as follows:
G
i
=
G
t
–
G
s
–
G
1
–
G
Mal
–
G
lac
F
i
=
F
t
–
F
s
–
F
f
where
G
s
= glucose released from sucrose =
S
/1.9;
G
Mal
= glucose
released frommaltitol = [(Mal
1
–Mal
2
)/1.9];
G
Lac
= glucose released
fromlactose=(Gal
2
–Gal
1
);
F
s
=fructosereleasedfromsucrose=
S
/1.9.
Calculate fructan content (
i
) in% as follows:
i
=
k
(
G
i
+
F
i
)
k
= 180 162 1
180
+ -
(
)
n
n
where
n
=averagedegreeof polymerization= [(
F
i
/
G
i
)+1] for pure
GF
n
mixtures.For inulin fromchicory
n
=10canbeused (
k
=0.91).
For oligofructose,
n
= 4 can be used (
k
= 0.925).
Amount of glucose formed by hydrolysis of lactose may be
calculatedbydividingdifference in lactosecontent beforeandafter
inulinase hydrolysis by 1.9. Amount of glucose formed by
hydrolysis ofmaltitol is the same as the amount of sorbitol formed
by hydrolysis ofmaltitol by inulinase hydrolysis.
Reference:
.
Revised: June 2003, April 2013
ã
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