Abstract:
Commercially available, fourteen different rice
varieties (improved and traditional) in Sri Lanka were
subjected to determine amylose content and important
physical properties. Under physical properties, milling
parameters (such as brown rice content, husk content and
total milling recovery), hardness and dimensions (length,
width & thickness) including water absorption capacity (by
dipping at 70°C for four hours) were measured. Amylose
content of each rice variety was determined by measuring the
optical density of amylose-iodine complex using
spectrophotometer, while amylopectin content was obtained
using the relationship equation. Results revealed, brown rice
content, husk content, total milling recovery, hardness and
water absorption capacities of these rice varieties were
within the range of 76-78%, 20-23%, 69-72% & 28-30%
respectively. Statistical analysis also indicated, those
physical properties of fourteen rice varieties were
significantly different to each other (p<0.05). Amylose &
amylopectin contents of rice varieties were found in the
range of 20 to 28% and 71 to 79% respectively, were
significantly different (p<0.05) to each other. According to
the correlation analysis, weak positive and weak negative
correlation ships (p<0.05) were observed for amylose
content vs. hardness and amylopectin content vs. hardness
respectively. Further, moderate positive correlation ship
(p>0.05) was reported in between amylose content and water
absorption capacity. While showing negative correlation
(p>0.05) between amylopectin and water absorption
capacity. Between hardness and water absorption capacity,
also had a weak positive correlation ship (p>0.05).
