Rice and rice bran proteins: Processing, functionalities, and applications

Rice bran and rice proteins have emerged as valuable plant-based protein sources, garnering attention for their nutritional quality, functional properties, and diverse applications. Rice bran, a by-product of rice milling, contains 10-15% protein, while rice contains about 5%. These proteins, composed of albumins, globulins, glutelins, and prolamins, offer a balanced amino acid profile and are highly digestible, hypoallergenic, and gluten-free, making them ideal for specialized nutrition.

Extraction of rice bran proteins involves sophisticated techniques such as alkaline-acidic extractions, ultrasound, enzymatic treatments, and advanced drying methods. While enzymatic treatments improve protein purity, they are often expensive and require several processing steps. The development of novel and effective extraction strategies is, therefore, vital to overcome low yield and functional quality issues associated with conventional techniques.

Functionally, these proteins exhibit excellent emulsifying, foaming, and water-binding capacities, making them valuable in various food formulations. They can be modified to enhance emulsion and oil-binding properties, expanding their applications in food development. Beyond their functional properties, rice proteins possess bioactive properties that contribute to food preservation and human health, including antioxidant, antimicrobial, antihypertensive, antidiabetic, and cancer-preventive effects.

Rice proteins also show promise in cosmetic and pharmaceutical industries due to their antimicrobial and antioxidant effects. They are being explored in biodegradable packaging materials and edible films. Despite being underutilized, ongoing advancements in processing technologies continue to enhance the extraction and functionality of rice bran proteins, expanding their applications across industries. With their unique properties and sustainability advantages, rice and rice bran proteins are poised to play a crucial role in future food systems and health-promoting products, addressing the growing global demand for high-quality plant-based proteins. As research progresses and new applications are discovered, these proteins are likely to become increasingly important in various sectors, offering sustainable and nutritious alternatives to traditional protein sources.