本研究是以高直鏈澱粉含量的秈米臺中在來1號為原料，添加不同濃度碳酸鈉製成鹼糕，再以可溶性總醣含量，可溶性直鏈澱粉含量，X-fay繞射分析，示差掃瞄熱分析，掃瞄電子顯微觀察，色差分析，硬度測試，探討高水分含量(85％)、高pH值下，碳酸鈉與米中澱粉的反應對鹼糕品質的影響。結果顯示，鹼糕老化現象隨著貯存時間增長而增加；唯在高水份環墳下，老化現象較緩慢；碳酸鈉能延緩鹼糕之老化。 鹼糕經貯存，在X-ray繞射圖之2θ=16.9°有明顯的老化結晶繞射峰，此老化結晶繞射峰為熱可逆(thermal reversible)，且非單由直鏈澱粉結晶所造成，又與示差掃瞄熱分析之老化吸熱峰之增加量及增加速率呈正相關，因此推測在θ=16.9°之老化結晶繞射峰可能歸因於直鏈澱粉和支鏈澱粉形成的共結晶(co-crystallization)。
The investigation on the change of physicochemical properties of the rice with different concentrations of Na2CO3 solutions under the high water content (85%) was carried out in order to elucidate the influence of reaction between sodium carbonate and starch in rice on the quality of alkaline rice cake. During the study, TCN1 was used as the sample. The result indicated that the degree of staleness on the alkaline rice cake was increased with the storage time prolonged at 5℃. However, the rate of staling was slow because of the high water content. The addition of Na2CO3 would retard the rate of staling. During the staling, the peak at 2θ=16.9° on the X-ray diffractogram was observed. The peak was thermal reversible and could not be due to crystallization of the amylose moiety during the retrograding. The size of the endothermic peak of DSC was proportional to the peak of X-ray diffractogram. It would be concluded that the peak might attribute to the co-crystalIizat[on of amylase and amylopectin.
