**1. Introduction**

The glycemic index (GI), which is based on glycemic response, is a well-established indicator of the increase in blood glucose potential of a carbohydrate food [1]. Low GI diets play a vital role in the management and control of diabetes [2]. Previous research reported that the probable effects of a low-GI diet are lowering insulin secretion in type 2 diabetes and decreasing daily insulin requirements in type 1 diabetes [3]. Higher consumption of water-soluble dietary fiber, such as isomaltodextrin, above the level recommended by the

**Citation:** Huang, D.-W.; Chan, Y.-J.; Huang, Y.-C.; Chang, Y.-J.; Tsai, J.-C.; Mulio, A.T.; Wu, Z.-R.; Hou, Y.-W.; Lu, W.-C.; Li, P.-H. Quality Evaluation, Storage Stability, and Sensory Characteristics of Wheat Noodles Incorporated with Isomaltodextrin. *Plants* **2021**, *10*, 578. https://doi.org/ 10.3390/plants10030578

Academic Editor: Ivo Vaz de Oliveira

Received: 16 February 2021 Accepted: 9 March 2021 Published: 18 March 2021

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American Diabetes Association (ADA) enhances glycemic control, reduces hyperinsulinemia, and lowers plasma lipid concentrations in people with type 2 diabetes [4]. However, noodles that are primarily formulated with wheat flour are not suitable for consumption by people with diabetes because of the high GI effects, which are evaluated for glycemic response (higher digestion rate or glucose absorption rate in the small intestine) [5,6].

In 2016, isomaltodextrin was assessed as a food that is generally recognized as safe (GRAS) by the US Food and Drug Administration (FDA) [7]. Isomaltodextrin presented health effects such as inhibition of fat absorption [8], anti-inflammatory properties, reduced risk of developing insulin resistance and associated metabolic diseases [9], diminished postprandial blood glucose [10], positive effects on intestinal flora [11], and inhibition of hen egg ovalbumin allergic response by inducing immune tolerance in mice [12]. Isomaltodextrin, a low-viscosity, water-soluble dietary fiber, which is enzymatically produced from corn starch, is also useful in reducing insulin secretion due to the reduction in sugar absorption by inhibiting the disaccharidase-related transport system in both rats and healthy humans [13]. Furthermore, isomaltodextrin improved glucose tolerance after sucrose, maltose, and maltodextrin loading and also greatly lowered the accumulation of body fat, regardless of changes in body weight in male Sprague–Dawley rats [14]. Hence, because typical noodles will simply increase blood glucose level, fortification of low-GI ingredients (isomaltodextrin) in noodles may benefit people with diabetes and allow then to enjoy noodles as part of a healthy diet. However, few studies have investigated the stability and physicochemical of isomaltodextrin under different storage conditions.

Storage stability studies of food products is a vital characteristic for both manufacturers and consumers, particularly in terms of food safety. Additionally important are physical and chemical features, appearances, and sensorial properties (organoleptic). Storage stability studies can provide important information to manufacturers and consumers to certify a high-quality product throughout the storage period [15]. Meanwhile, the products must be acceptable for consumers and comply with the nutritional value on the labeling. Choosing suitable storage-stability study models and data-analysis techniques are important to anticipate the shelf life, consider the changeability in environmental conditions, and guarantee real-time monitoring of products [16]. Appropriate scientific estimation and calculation of the storage stability of food commodities maintains the safety and quality of the products and can prevent food waste during the distribution and consumption stages of the food chain [17].

Therefore, this study aimed to investigate and evaluate the storage stability study of wheat noodles fortified with isomaltodextrin, in terms of physicochemical characteristics, microstructure features, dietary fiber profile, cooking quality, and sensory attributes during different storage temperature and periods. Meanwhile, it is hypothesized that isomaltodextrin wheat noodles along the 24 months of storage at low temperature, which is 4 and −20 ◦C, with only minor alterations in texture and sensory quality.

### **2. Materials and Methods**

All chemical and reagents used in this study were purchased from Sigma-Aldrich Chemical (St. Louis, MO, USA) (ACS certified grade). Total dietary fiber assay kit (K-TDFR) was provided by Megazyme (Wicklow, Ireland). Isomaltodextrin (GRAS no. 610) was purchased from the Hayashibara (Okayama, Japan). All samples were established and analyzed in triplicate.
