SLQ – 6A coarse fiber determinator is a set of the instrument
for determining coarse fiber to adopt chemistry and physics technology .The instrument
is applicable to analyze coarse fiber content in food, animal feed and other
The design principle of the instrument is based on
acid and alkali washing method. It gathers the function to handle and flushed
with sour or alkali, is adopted a closing construction and electricity heat method,
which can determine 6 samples at the same time, does not need to transfer
sample, can resolve out fiber in the material. It as well as can regulate
arbitrarily the temperature needed for the single sample. That attains an
accurate and fast purpose. During operate, may control timing, doesn’t overflow
the harmful material, so insure that the test data is dependable and veracious
and be beneficial to the environmental decontamination, operate is convenience for
personnel. Consequently the instrument is an ideal instrument to determine coarse
fiber for the institute, Industry of food and animal feed, also is the instrument
of experience and education for university and college.
Ⅱ. Working Principle
Using definite concentration acid or alkali digests
sample under the particular condition, then using ether and alcohol removes the
material dissolving ether, ignite at high temperature and deduct mineral,
residual material is called as coarse fiber. It is not an accurate chemistry composition,
just in accepted rule measure a compendia composition which contains mainly fiber,
a little half cellulose and lignin.
Ⅲ. Technique Parameter
1. Measurement scope: Coarse fiber content in all kind
of food, animal feed and other agriculture by-products.
2. Measurement accuracy: ≤0.2%.
3. Re-appear: The parallelism test result ≤0.4%.
4. Measurement time: 90min/ batch.
5. Test sample number at the same time: 6/ times
6. Power supply: 220 (V)±10﹪; 50HZ.
7. Power: 2KW
8. Shape size: 560×520×640 mm3.
9. Weight: 30kg
Ⅳ. Usage Elucidation
Coarse fiber determinator;
Analyze balance: min 0.0001 g;
Electrical oven (1500W, 50-150℃);
Desiccator with the silicon of changing color, tow
muffle furnace (2KVA, 200-1000℃);
Pulverizer or mortar for the laboratory;
mm2 aperture (40 mesh)
Sulfuric acid (H2SO4), AR;
Sodium hydroxide (NaOH),AR;
95% Alcohol, AR;
Diatomaceous earth (filter aid)
3. The operation preparation
a. Reagents preparation
1, a solution of sulfuric acid (0.128mol / L): Take
concentrated sulfuric acid (analytical grade) to about 69 mL, diluted to 1000ml
with distilled water, dried calibration solution of known concentration of
NaOH, their concentration adjusted to 1.28 ± 0.005mol / L of liquid sulfuric
acid, can be diluted 10-fold with distilled water before use.
2, an alkaline solution (0.312mol / L): Take about
174ml clarify NaOH solution saturated with CO2-free distilled water to dilute
1000ml Gasser oscillation even with a known concentration of acid after
calibration standard solution to adjust its concentration to 3.12 ± 0.005 mol /
L of a base liquid, can be diluted 10-fold with distilled water before use.
B, sample preparation
1, take a representative sample, pick impurities,
according to quartering take about 25g.
2, the sample was dried in a home 60 ~ 65 ℃ oven for about 8 hours, cooled and
pulverized or grinder, all through 0.84mm2 (20 mesh) sieve, wherein greater
than 0.45mm2 (40 mesh) is not less than 50%; less than 0.25mm2 (60 mesh) shall
not exceed 10%.
3, the fat content of the sample more than 1%
defatted (available residue was determined after analysis of the fat, no fat).
4, the crucible was washed with water, to wash the
crucible without leaving any impurities, placed in a drying oven for about 1
hour (at a temperature of 105 ℃) moved into a desiccator to cool to room temperature, serial
number, and then placed in the oven within the reserve.
(D), the steps
1, in the crucible numbered after the first 1g of Celite, and then accurately
weighed sample average net dry or drying anhydrous defatted sample 1-3g
(cereals 2-3g) accurate to 0.0001g.
2, power, water supply, turn the mains switch (open water as far as possible to
ensure full condensation effect).
3, respectively, the corresponding acids, bases, water hose is connected
properly and host cooking liquor is poured into a solution with a good right
amount (about 1L), turn on the power.
4, open acid, alkali, water preheating power small switch, pre-heated to a boil
(about 80 ℃).
5, the crucible containing the sample transferred to a greenhouse instruments
(note this time remains accurate unbiased position: the lower part of the
crucible into the center seat, the upper part of the hole is aligned Digestion
tube under protective cover; Press the handle and lock check again after tight
crucible position is accurate, the lower valve all closed, pulled out one by
one heater handle.
6. Acid Digestion: first open 1-6 Dosing valve, open acid
valve, then open the dosing switch, has been preheated to about 5ml H2SO4
solution were added to the crucible, after the addition of switching off dosing
switch, and then open the suction switch, one by one under the open valve,
exhausted solution, sucked off all the switches and lower valve. Then H2SO4 has
been preheated to the mark in the middle line (about 150ml), and then add 8 to
10 drops in each Digestion tube octanol, start the timer, respectively, at the
same time as needed to open heater power switch, the selected bit adjustment
knob can be observed a single heater
voltage. And raised to the highest voltage (220V). Digestion liquid boil until
the voltage down individually adjusted to the heating temperature of the sample
without precipitation, start timing knob to 30min, keeping Digestion simmering
liquid (such as found in the sample sticking to the wall can eliminate
additional cooking liquor). When heating is automatically stopped.
7, open the suction switch, and then one by one under the open valve Digestion was deprived of rapid (within 10min
exhausted) and washed with hot distilled water to neutral residue (about three
times), the exhausted wash liquid, such as found in the leaching process is
blocked off suction when the crucible switch, blow open the switch with a jet recoil found after bubbles appear
within Digestion tube blow off switch, open the switch continues to suck sucked
sucking liquid after closing the suction switch.
8 Press (6) Step alkali Digestion.
9, press (7) Step extractor alkali cooking liquor consumption.
10, bleaching and degreasing, all closed lower valve,
with a fat belly straw respectively Digestion tube catchy added in three
portions of 95% ethanol, soak, filtration (each about 20ml, each immersion time
of about 1min), then added in three portions of ether, rinse (each about 20ml),
(Ruoyi defatted sample does not require rinsing with diethyl ether).
11, rinsed with acetone sample 3 times, washed once with distilled water. (Each
12, the left hand pressing the handle locking hook pulled slowly rising, it is
reset with gloves, remove the sample crucible there until the ether and ethanol
all volatiles finished, then shifts in oven at a temperature of 130 ℃, bake 2 hours, was brought out in a desiccator to cool
to room temperature, the weighed (A1).
13, the crucible after weighing, put into a furnace burning 500 ℃ resistor 30min, (must be placed in a cold crucible
furnace, followed by heating) until the furnace temperature dropped to below
200 deg.] C, was brought out in the resistance furnace after weighing
desiccator cooling to room temperature (A2).
14, the measurement results calculated
CF% = (A1-A2) ÷ S1 × 100
Where: CF- percentages of crude fiber (%)
A1- crucible + + crude fiber and ash
residue mass (g)
A2- crucible + ash residue and mass (g)
S1- sample weight (g)