Effect of Pre-Heating on Enhancing the Anti-Digestive and Antioxidant Properties of Curcumin Rice by Self-Emulsifying...

Area of Science:

• Food Science
• Nutritional Biochemistry
• Materials Science

Background:

• Hydrophobic phytochemicals like curcumin have low bioavailability.
• Turmeric rice is a popular Asian staple, but curcumin's binding mechanism in rice is not well understood.
• Self-emulsifying delivery systems (SEDSs) can improve the absorption of poorly soluble compounds.

Purpose of the Study:

• To develop curcumin instant rice (CIR) using SEDS and pre-heating.
• To investigate the effects of different processing methods (steamer steaming vs. cooker water-boiling) on CIR characteristics.
• To evaluate the impact of processing on starch digestibility, curcumin loading, and antioxidant properties.

Main Methods:

• Curcumin SEDS were prepared and used to create CIR with pre-heating.
• Two processing methods were applied: steamer steaming (SST) and cooker water-boiling treatment (CWBT).
• Analysis included starch digestibility (slowly digestible starch, resistant starch), curcumin content, total phenolic content, antioxidant activity, differential scanning calorimetry (DSC), and X-ray diffraction (XRD).

Main Results:

• CIR produced via SST showed increased slowly digestible starch (26.43-28.38%).
• CWBT significantly enhanced resistant starch (up to 47.81%), curcumin loading (up to 66.50 mg/100 g), total phenolic content, and antioxidant activity.
• CWBT disrupted starch structure, forming amylose-lipid complexes, confirmed by DSC (type II crystals) and XRD (V-type patterns).

Conclusions:

• Pre-heating and CWBT are effective strategies for enhancing curcumin encapsulation and resistant starch formation in CIR.
• The developed CIR exhibits improved bioavailability of curcumin compared to conventional turmeric rice.
• This processing approach offers a promising method for fortifying rice with hydrophobic compounds.