# The Effect of Inulin Addition on Rice Dough and Bread Characteristics
## 1 Introduction  
Inulin is widely found in more than 36,000 plant species as a reserve polysaccharide. It is commonly extracted from inulin-containing plant sources, such as chicory roots (_Cichorium intybus_ L.) and Jerusalem artichoke tubers (_Helianthus tuberosus_ L.), as well as from novel sources, such as globe artichoke inflorescence (_Cynara cardunculus_ L.) and its by-products [1]. Inulin is a linear polydisperse carbohydrate material consisting mainly of \(\beta\)-(1\(\rightarrow\)2) fructosyl-fructose links. Because of the \(\beta\) configuration of the amomeric C2 in its fructose chromosomes, inulin resists hydrolysis by the digestive enzymes found inside the human small intestine, being classified as nondigestible food fiber [2; 3; 4]. Inulin reduces the risk of gastrointestinal diseases, decreases the levels of pathogenic bacteria in the intestine, and relieves constipation. A beneficial effect on bowel function is obtained with a daily intake of 12 g of inulin [2; 5; 6]. It exhibits many other health benefits; it stimulates the human body's immune system, decreases the risk of osteoporosis by increasing mineral absorption, and does not lead to a rise in serum glucose or stimulate insulin secretion, among other benefits [2; 5; 7; 8]. Inulin may be widely used in the food industry as a prebiotic, a fat and sugar replacer, as well as dietary fiber [5]. It is stable in temperatures up to 140 \({}^{\circ}\)C and can, therefore, be processed easily in bread baking [9]. Inulin incorporation into baked goods can increase their nutritional quality as well as technological properties [10]. It is used to replace flour in bread at a rate of 3-10%. Inulin is not considered to be a food additive [11]. Its taste is neutral, being without any off-flavors or an aftertaste [12]. Since it exhibits many health benefits, it can be used ad libitum [9]. Approximately 93% of individuals with celiac disease consume bread daily [13]. Commercially produced breads are often prepared from various blends of starches and flours [14; 15]. The absence of gluten presents a technological challenge, as wheat proteins play crucial roles in bread production and quality [16]. During dough preparation, proteins form a continuous matrix with viscoelastic behavior [17]. Wheat dough exhibits a high capacity to retain CO\({}_{2}\) and has low consistency. These properties result in high-quality bread with a large volume and good textural parameters, such as low hardness, high cohesiveness, and resilience [17]. In contrast, gluten-free doughs display different characteristics, which may be attributed to the molecular weight of the protein molecules and variations in chemical composition, primarily a lower content of the amino acid lysine [18]. Rice flour is frequently used in gluten-free bread baking because of its colorlessness, nutritional characteristics, bland taste, and low hypoallergenic properties. Flours with more distinctive colors, tastes, and flavors compared with wheat may not appeal to some consumers [19; 20; 21]. Although nutritional quality varies among products, gluten-free bread is usually low in fiber, proteins, micronutrients, vitamins, and minerals such as iron, zinc, magnesium, and calcium [14; 19; 20; 22]. Gluten-free breads have a higher glycemic index than gluten-containing products because of the use of starches and sugars [23; 24]. The texture and taste of bread are the most important characteristics and are often the main reasons why people dislike currently available gluten-free bread [13]. Inulin's ability to create a gel might be expected to improve the poor ability of gluten-free dough to trap leavening gas. However, the inulin's ability to form a gel is affected by the length of its chain. Short-chain inulin cannot form a gel, natural inulin forms a gel at concentrations above 30% \(w/w\), and long-chain inulin forms a gel in the range of 20-40% \(w/w\) at room temperature due to its lower water solubility [10].