Akademik Veri Yönetim Sistemi
TURKISH JOURNAL OF AGRICULTURE AND FORESTRY, cilt.49, sa.3, 2025 (SCI-Expanded)
Bitterness arising from naringin is a problem in citrus juices, especially grapefruit juice, in terms of consumer preference. Naringinase enzyme is used to eliminate the bitterness. In this study, naringinase was extracellularly extracted, isolated, and characterized from an Aspergillus niger strain in different media. The extracted enzyme was added to grapefruit juice at different concentrations (0.1%, 0.5%, 1%) (0.078, 0.39 and 0.78 EU) and stored at different temperatures (25, 35, and 45 degrees C) for 5 h. At the end of the first and fifth h, the amount of naringin, physicochemical properties, phenolic profiles, and antioxidant activities of the grapefruit juice were determined. The optimum ionic strength of naringinase was determined as 0.5 M, optimum pH value as 5.0 in citrate buffer, and the optimum temperature as 50 degrees C. According to the results, the enzyme was least affected by Mg+2. There was a 65.58% decrease in naringin in samples with 1% enzyme added and incubated at 45 degrees C. The highest level among the phenolic compounds was found for quinic acid (13,914.48 ppb). At the end of the 5th h, no change was observed in the dry matter, pH, and total acidity values of grapefruit juice with 0.1% enzyme concentration at 25 degrees C. Under the same conditions, the greatest change was observed in color intensity, color tone, total phenolic content, and antioxidant capacity.