Gluten-free industry has experienced consistent growth with increasing the number of individuals with celiac disease. Among gluten-free products, the popularity of rice noodles has been worldwide increasing over the recent years. However, rice noodles have several processing limitations such as high cooking turbidity and long cooking time. Therefore, various ingredients have been incorporated into the formulation of rice noodles in order to improve their quality attributes. In this study, turanose which is known to be a new sugar alternative with low sweetness was applied to rice noodles and their effects were characterized in terms of thermal, rheological, and textural properties. Gluten-free rice noodles were prepared with different levels of turanose (0.5, 1.0, 1.5%, w/w) by using a twin-screw extruder. Rice flour with turanose had higher gelatinization temperature and also showed higher enthalpy values after storage at 4°C. The use of turanose also increased the pasting and mixing parameters of rice flour. In addition, the application of turanose to rice noodles affected their qualities such as texture and cooking loss. Thus, this study demonstrated that turanose could positively contribute to enhancing the qualities of gluten-free rice noodles as a new additive.
본 연구에서는 냉동저장에 따른 제빵용 밀가루 반죽의물리적 특성 변화를 분석하기 위하여, 냉동생지를 제조 후2주간 -20oC에서 냉동 저장하면서 신장특성, 텍스처, 부피,색상 등의 품질 특성을 측정하고 이를 냉동저장을 하지 않은 대조구와 비교하였다. Extensograph를 활용하여 냉동저장한 밀가루 반죽은 신장도와 신장저항도가 증가하였으며 R/E도 증가함을 확인하였다. 냉동생지를 이용하여 빵을제조한 경우 빵의 부피는 감소하고, 이에 따라 경도는 증가하였고 대조구와 비교하여 어두운 표면이 관찰되었다. 이러한 본 연구의 결과는 냉동 저장 반죽을 이용한 제품제조 시 냉동생지의 물리학적 특성을 파악하여 그 품질을 개선 및 보완하는데 필요한 기초 자료로 활용 될 수 있을 것으로 기대된다.
In order to develop an efficient microbial source of cellulase enzyme system, cellulolytic fungal strain was newly isolated from traditional Korean nuruk samples in the present study. The crude enzyme extract of this fungal strain, avicelase, CMCase and β-glucosidase activities reached the maximal points of 6.73, 3.22, and 5.64 units/mL, respectively and was used for the subsequent enzymatic saccharification on pretreated deproteinised and lipid-extracted rice bran. This strain was identified as Penicillium sp. determined by cellular fatty acid composition analysis. Three different pretreatment conditions were evaluated on the deproteinised and lipid-extracted rice bran at 121oC/1.5 psi for 5 different residence times: one with 0.1 N sulfuric acid, another with 0.1 N sodium hydroxide, and the last with distilled water. The greatest enzymatic saccharification yield increased up to 75.2% from acid-catalyzed autoclaving pretreatment for 30 min. The acid-catalyzed autoclaving pretreatment enhanced the saccharifying ability of the newly isolated cellulolytic fungal strain on the deproteinised and lipid-extracted rice bran.