In the quest to enhance the nutritional value and functional properties of staple foods, researchers have made a significant stride by exploring the interplay between rice starch and inulin, a dietary fiber. A recent study led by Yuan Ye from the College of Food Science and Technology at Hunan Agricultural University in China, published in *Food Chemistry: X* (translated as *Food Chemistry: New Frontiers*), sheds light on how inulin with varying degrees of polymerization can transform the structure, properties, and digestibility of rice starch.
The study investigated the effects of three types of inulin on rice starch, revealing that the addition of inulin significantly alters the viscosity, gelatinization, and retrogradation properties of the starch. “The viscosity, breakdown, and setback values of the composite systems decreased, indicating that inulin can modify the pasting properties of rice starch,” explained Ye. This finding is crucial for the food industry, as it suggests that inulin can be used to tailor the texture and stability of starch-based products.
One of the most notable outcomes of the research is the reduction in gelatinization enthalpy and retrogradation enthalpy after 14 days of storage. The gelatinization enthalpy decreased from 9.54 J/g to as low as 8.79 J/g, while the retrogradation enthalpy dropped from 4.58 J/g to around 3.44 J/g. “This indicates that inulin can inhibit the retrogradation of rice starch, which is beneficial for extending the shelf life of starch-based products,” Ye noted.
The study also found that the addition of inulin significantly reduced the relative crystallinity and formation of ordered structures in the composite systems after 14 days of storage. This is a critical insight for the food industry, as it suggests that inulin can be used to control the crystallinity and texture of starch-based products.
Perhaps the most compelling aspect of the research is its impact on the digestibility of rice starch. The study revealed a significant decrease in rapidly digestible starch, from 69.63% to as low as 45.48%, and increases in slowly digestible and resistant starch contents. “This suggests that inulin can be used to create starch-based products with a lower glycemic index, which is beneficial for consumers looking to manage their blood sugar levels,” Ye explained.
The effects of inulin on rice starch were found to depend on its polymerization degree and concentration, with 3.0% short-chain inulin demonstrating the most pronounced improvement in starch properties. This finding opens up new avenues for the food industry to explore the use of inulin as a functional ingredient in a wide range of products.
The commercial implications of this research are substantial. By leveraging inulin to modify the properties of rice starch, food manufacturers can create products with improved texture, stability, and nutritional value. This could lead to a new generation of starch-based foods that are not only more appealing to consumers but also more beneficial for their health.
Moreover, the energy sector could also benefit from this research. As the demand for sustainable and renewable energy sources grows, the development of starch-based materials for bioenergy applications is becoming increasingly important. The findings of this study could contribute to the creation of more efficient and effective starch-based bioenergy materials.
In conclusion, the research led by Yuan Ye and his team at Hunan Agricultural University represents a significant advancement in our understanding of the interplay between inulin and rice starch. By harnessing the power of inulin, the food and energy sectors can unlock new opportunities for innovation and growth. As the world continues to grapple with the challenges of food security and sustainable energy, this research offers a promising path forward.