Procedures for Measuring quality of milled rice

Milling degree
Milling degree is computed based on the amount of bran removed from the brown rice. To obtain the weight of brown rice, dehull the paddy samples using the Laboratory Huller.
Estimate the percent milling degree using the following equation:
Milling recovery
Using the Abrasive Whitener, mill the dehulled samples. Compute milling recovery by dividing the weight of milled rice recovered by the weight of the paddy sample, as follows:
Dockage in Milled Rice
Select, segregate and weigh the foreign matter. Record the number of unhulled grains collected from the sample. Determine the percentage of dockage of milled rice using the equation:
Broken grain
Using the Grain Grader, separate the broken grain from the whole grains. Compute the percentage of the head rice and brokens using the following equations:
Chalkiness
A visual rating of the chalky proportion of the grain is used to measure chalkiness based on the standard Evaluation System SES scale presented below:

Scale
% area of chalkiness
1
less than 10
5
10-20
9
more than 20
Select, segregate and weigh the chalky grains (SES Scale 9). Determine the % chalky grain using the equation:
Whiteness
Measure the grain whiteness using the Whiteness Meter. Separate and weigh yellow-fermented grains. Calculate the percentage of yellow/fermented grains using the formula:
Grain Shape
Follow the procedure of determining grain shape of paddy. Based on the length to width ratio, the shape of the milled rice will be determined. L/W ration is given by:
The ISO Classification is as follows:
Scale
Shape
L/W ratio
1
Slender
Over 3.0
3
Medium
2.1 – 3.0
5
Bold
1.1 – 2.0
9
Round
1.0 or less
1000 grain weight
Count and weigh 1,000 whole grains.
Amylose content.
Select twenty grains and ground them in a Cyclone Mill. Amylose content is analyzed using the simplified iodine colorimetric procedure. Samples are categorized into low, intermediate and high based on the following grouping:
Category
%Amylose Content
Waxy
1-2
Very low amylose
2-9
Low
10-20
Intermediate
20-25
High
25-30
Gelatinization temperature (GT)
GT is measured by determining the alkali-spreading value for which the alkali digestibility test is employed. Grains are soaked in 1.7% KOH and incubated in a 30oC oven for 23 hours. Measurement ranges are based on the following: Gelatinization temperature is estimated by the extent of alkali spreading and clearing of milled rice soaked in 1.7% KOH at room temperature or at 39oC for 23 hours. The degree of spreading is measured using a seven-point scale as follows:
1. grain not affected
2. grain swollen,
3. grain swollen, collar incomplete and narrow,
4. grain swollen, collar complete and wide,
5. grain split or segmented, collar complete and wide,
6. grain dispersed, merging with collar; and
7. grain completely dispersed and intermingled.
Category
Temp ranges (oC)
Alkali Spreading Value
Low
55-69
6-7
Intermediate
70-74
4-5
High
75-79
2-3
Gel consistency
Select from two to 10 grains and ground separately in the Wig-L Bug. Gel consistency is measured by the cold gel in a horizontally-held test tube, for one hour. Measurement ranges and category are as follows:
Category
Consistency, mm
Soft
61-100
Medium
41-60
Hard
26-40