鰹節の切削加工に及ぼすガラス転移温度の影響 <技術論文>

Effects of the Glass Transition Temperature on the Shaving Characteristics of Katsuobushi (boiled and dried bonito)

羽倉 義雄

行友 純恵

鈴木 徹

鈴木 寛一

日本食品科学工学会誌

This study assessed the effect of different temperatures on the product yield of flakes derived from shaving commercial Katsuobushi (boiled and dried bonito). The Katsuobushi was shaved using a household Katsuobushi-plane. The chosen temperature was lower than the glass transition temperature (glass state), and higher than the glass transition temperature (rubber state). Also, the load and energy associated with shaving each Katsuobushi was measured and used to compare Katsuobushi processing characteristics at the glass state and rubber state.

The results showed that the product yield in the rubber state was consistently higher than for the glass state. The shaving load of rubber state Katsuobushi was lower than that associated with the glass state. The rubber state Katsuobushi was shaved with a shaving load of between eighty-five and ninety percent that of the glass state. The shaving energy for the rubber state Katsuobushi was less than that required for the glass state. Regarding specific shaving energy, which is the shaving energy necessary to get 1g of Katsuobushi flake, the energy exerted for the rubber state Katsuobushi was less than that of the glass state. The rubber state Katsuobushi was shaved using only twenty-five to forty-six percent of the energy needed for the glass state.

From these results, it was shown that rubber state Katsuobushi could be shaved more efficiently than glass state Katsuobushi. This indicates the potential for laborsaving and boosting material yield in shaving Katsuobushi on a commercial scale.

鰹節の切削に及ぼすガラス転移温度の影響を検討した. 水分11.34%の鰹節をガラス状態(25℃)とラバー状態(70℃)に設定し, それらを鰹節削り器で削り, 削り節の歩留り, 切削抵抗および切削エネルギーを測定した.

切削物量の評価では, ガラス状態よりもラバー状態の鰹節の方が総切削量は多かった. また歩留りについても, ガラス状態よりもラバー状態の鰹節の方が常に高い値を示していた.

切削抵抗の評価では, ガラス状態よりもラバー状態の鰹節の方が切削抵抗は小さく, ガラス状態の85～90%程度の切削抵抗でラバー状態の鰹節を切削することができた.

切削エネルギーの評価でも, ガラス状態よりもラバー状態の鰹節の方が切削エネルギーは小さく, ガラス状態の77～80%程度の切削エネルギーでラバー状態の鰹節を切削することができた. また比切削エネルギー(1gの削り節を得るために必要な切削エネルギー)についても, ガラス状態よりもラバー状態の鰹節の方が小さく, ガラス状態の25～46%程度の比切削エネルギーでラバー状態の鰹節を削り節に切削することができた.

以上の結果, 鰹節の切削工程では, ラバー状態の鰹節の方が, 効率的に切削が可能であることが明らかとなった. これは鰹節を工業的に切削する際の省力化や歩留り向上の可能性を示唆している.

家政学・生活科学 [ 590 ]

日本語

日本食品科学工学会

[ISSN] 1341-027X

[DOI] 10.3136/nskkk.53.518

[NCID] AN10467499

[DOI] http://dx.doi.org/10.3136/nskkk.53.518