The effect of addition of turmeric (Curcuma longa L.) on the rancidity process of concentrate feed based on lactic acid bacteria fermentation during aerobic storage

This study aimed to determine the effect of the addition of turmeric (Curcuma longa L.) on rancidity process of concentrate feed based on lactic acid bacteria fermentation (CFLAB) in aerobic storage conditions. The treatments were the addition of turmeric extract, turmeric flour, and vitamin E in feed with levels of 0, 0.5, 1, 1.5, 2 and storage for 0, 10, 20, 30, 40 days with three replications. Antioxidant activity was carried out by 2.2-diphenyl-1-picrylhydrazyl analysis. The pH, free fatty acids numbers (FFA), and organoleptic analysis were determined in CFLAB quality during storage. DPPH analysis showed that turmeric extract and vitamin E had the best antioxidant activity. Addition of 2 turmeric extract, 2 turmeric flour, and 2 vitamin E lowered the pH. The addition of antioxidant compounds decreased FFA levels compared to controls except for the addition of vitamin E, but in terms of the percentage increase in FFA levels during storage, the addition of 1,5 turmeric flour gave the best results. Physical quality in the form of color, odor, texture, and fungus indicated that the quality of the CFLAB was able to keep in good condition due to the antioxidant sources addition.