The Impact of Enzyme Type, Temperature, and Grinding Roller Interval on Barley Malt-Based Beverages

Malt is a vital ingredient in the brewing and food industries, as it influences the sweetness, flavor, and color of the final products. The quality and soluble solids content of barley-derived malt depends on temperature, enzyme type, and grinding roller interval. This study aimed to determine the optimal conditions for maximizing the soluble solids in Iranian malt.

Malt samples were treated at 57 and 72 °C, employing glucan maltohydrolase (GMH) and glucohydrolase (GH) enzymes, and grinding roller intervals of 0.6, 0.8, and 1 mm. The malt samples were then subjected to chemical analyses, including Brix measurement, iodine test, and pH determination.

The results showed that higher temperatures increased the Brix value and decreased the pH value of the malt samples. No significant differences in Brix and pH were observed between the GMH and GH enzymes. Smaller grinding roller intervals (0.6 mm) increased the Brix value and decreased the pH. The optimal conditions for maximizing the soluble solids content were 72 °C with the GMH enzyme and a 0.6 mm roller interval (Brix = 7.8 g/100 cc, pH = 5.32). The temperature significantly influenced the iodine test, confirming starch hydrolysis into sugar at 72 °C.

This study recommends reducing the grinding roller interval from 0.8 to 0.6 mm and increasing the temperature from 57 to 72 °C to significantly enhance the malting process. Therefore, using a 72 °C temperature and 0.6 mm roller gap is advised for better malting efficiency.