影響米穀粉保氣性之因子

Abstract

稻米所含的蛋白質過敏性低，且有多樣化新興的米穀粉加工製品。然而，米穀粉相較於小麥麵粉在加工上並沒有明確的品質規範、加工性質指標參數供加工者參考。但近年來台灣地區稻米的消費量逐年下滑，為了提升稻米消費量，故建立一套米穀粉品質檢測指標，判斷米穀粉的物理性質，選擇適配的米穀粉進行加工製造。本研究選擇三種稉米與四種秈米來源，視直鏈澱粉含量涵蓋13.5~31.6%範圍，乾式研磨有速率快、損失低的特點，利用二種乾磨方式生產不同粒度範圍米穀粉末，評估米穀粉的化學組成與物理性質，利用蒸煮後的保氣性作為指標，建立指標與組成、性質間之關聯性。試驗結果可以歸納出Y=0.366AAC+0.147DS-0.617pH-0.280'G''max'-0.180SP+1.245，米穀粉蒸煮膨發體積(Y)，主要影響因子為米穀粉的新鮮度(pH)，其次是米穀粉視直鏈澱粉含量(AAC)、G''max、米穀粉膨潤能力(SP)、米穀粉破損澱粉(DS)。並從中知道對於需要膨發的產品，視直鏈澱粉含量是最主要的正面影響。

Rice is a typical Asian food ingredient; recently, several novel processed foods utilize rice flour as a major component because of its hypoallergenic characteristic. Compared with wheat flour, rice flour has only a small amount of food-processing and quality inspection indicators for practitioners as a reference. This study aimed to evaluate the physical properties of rice flour and further included gas retention and other indirect factors to construct the relationship between food-processing property and physical factors via multivariate regression analysis. We selected three types of Japonica rice flour and four types of Indica rice flour (apparent amylose content: 13.5 ~ 31.6 %) and conducted dry milling to produce different particle size rice flours. Based on the regression result, Y = 0.366AAC + 0.147DS - 0.617pH - 0.280'G''max' - 0.180SP + 1.245, the primary factors that contributed to the steamed expansion volume were freshness (pH), apparent amylose content (AAC), G''max, swelling power, and damaged starch (DS) in order of importance. Nevertheless, apparent amylose content is a significant positive impact on expanded food products.