Gluten-Free Rice Malt Extract Powder: Pilot-Scale Production, Characterization, and Food Applications

TL;DR

A gluten-free rice malt extract powder was successfully produced at pilot scale and shown to be a safe and functional alternative to barley malt extract for food and industrial uses.

Contribution

The novel contribution is the pilot-scale production and characterization of a gluten-free rice malt extract powder from Thai Chainat 1 rice.

Findings

The rice malt extract powder contains high levels of fermentable sugars, protein, GABA, and thiamine, with no detectable gluten or contaminants.

The powder met microbiological safety standards and retained stability and bioactive compounds for up to three years.

It supported microbial growth in culture media and was used to produce a gluten-free malt beverage with acceptable quality.

Abstract

Background/Objectives: This study reports pilot-scale production of gluten-free rice malt extract powder from Thai Chainat 1 rice as a sustainable alternative to barley malt extract. Methods: The process combined controlled malting with sequential enzymatic hydrolysis, optimized through bench-scale validation and scaled up to a 1500 L pilot system. Results: The resulting powder was rich in fermentable sugars (maltose 43.9 g/100 g, glucose 14.3 g/100 g), protein (5.2 g/100 g), γ-aminobutyric acid (GABA, 245.2 mg/100 g), and thiamine (0.64 mg/100 g), while free of detectable gluten, aflatoxins, and heavy metals. Microbiological quality met international safety standards. Shelf-life studies under ambient and accelerated conditions demonstrated chemical stability and bioactive retention for up to three years in laminated and HDPE packaging. Application trials confirmed that the rice malt extract powder supported yeast, bacterial, and mold growth comparably to commercial malt extract in culture media, with optimized yeast–mold agar formulations enabling direct substitution without supplementary glucose. The powder was further applied to a gluten-free malt beverage, yielding a beer-like product with acceptable physicochemical and nutritional quality, though residual alcohol levels exceeded the non-alcoholic threshold and required process optimization. Conclusions: Rice malt extract powder represents a safe, functional ingredient suitable for food, beverage, and industrial microbiology applications, offering opportunities to reduce import dependency and advance gluten-free innovation in emerging markets.

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