アセチル化リン酸架橋澱粉糊化液の流動特性に与える澱粉の化学変性程度の影響 <技術論文>

Influence of Chemical Modification Level of Starch on Flow Properties of Gelatinized Phosphate Cross-linked and Acetylated Waxy Corn Starch Suspensions

Asada Hitoshi

Suzuki Kanichi

日本食品科学工学会誌

Waxy corn starch was modified doubly by acetylation and cross-linking with acetic vinyl and phosphorus oxychloride (POCl3). Degree of cross-linking was varied using 0.008∼0.02% phosphorus oxychloride, and acetylated substitution was adjusted to the same degree on all starch samples. Flow properties of these starch suspensions were determined by using a capillary tube viscometer. Flow parameters of these starch suspensions were markedly changed over 1.21×10-4% (w/w) of the phosphorus content. Logarithmic value of the consistency factor, logK and apparent viscosity, logμa, for the power law model, decreased with increasing phosphorus content of starch. When the phosphorus content of these modified starch (cross-linking level) was over 9.00×10-4% (w/w), the swelling of starch granules was retarded. This led to the small change in logK and logμa values. Flow properties of modified starch suspensions were found to be affected rather by the cross-linking modification of starch than by the acetylated modification.

ワキシーコーンスターチを由来澱粉として, アセチル置換度を一定にし, リン酸架橋度を段階的に変えたアセチルリン酸架橋澱粉を試作し, 澱粉の化学変性処理が, その澱粉糊化液の流動特性(レオロジー)に与える影響を検討した結果, 以下の知見を得た.

(1) 天然澱粉にリン酸架橋すると, 1.21×10-4%(w/w)の微量の架橋リン含量で, その糊化液の流動特性などのレオロジー特性は大きく変化した.

(2) 流動特性を流動パラメータで評価すると, リン酸架橋澱粉の糊化液は, 架橋リン含量に伴ってパラメータは減少した. 特に, 架橋リン酸含量の増加に従ってコンシステンシー係数Kとみかけ粘度μaの常用対数値logKとlogμaは, 架橋リン含量に従って減少した.

(3) 架橋リン酸含量が9.00×10-4%(w/w)以上になると, 糊化澱粉の膨潤抑制が強くなり, コンシステンシー係数Kとみかけ粘度μaの架橋リン酸含量に対する減少割合は小さくなった.

(4) 澱粉糊化液の流動特性は, リン酸架橋の程度に大きく影響を受けることがわかった.

Domestic arts and sciences [ 590 ]

jpn

日本食品科学工学会

[ISSN] 1341-027X

[NCID] AN10467499

[URI] http://www.journalarchive.jst.go.jp/japanese/jnlabstract_ja.php?cdjournal=nskkk1995&cdvol=51&noissue=11&startpage=613