Effect of purple sweet potato levels (Ipomoea batatas L.) carbohydrate sources on fermentation kinetics and lactic acid production by Lactobacillus paracasei

• Published in: IOP conference series. Earth and environmental science 2021-03, Vol.686 (1), p.12048
• Main Authors: Tasminto, D, Bachruddin, Z, Kurniawati, A, Muhlisin
• Format: Article
• Language: English
• Subjects: Acid production; Acids; Bacteria; Biodegradation; Carbohydrates; Degradation; Fermentation; Ipomoea batatas; Kinetics; Lactic acid; Lactic acid bacteria; Lactobacilli; Lactobacillus paracasei; Nutrition; pH effects; Potatoes; Substrates; Sweet potatoes; Variance analysis; Vegetables
• ISSN: 1755-1307; 1755-1315
• DOI: 10.1088/1755-1315/686/1/012048

This research aims to determine the effect of purple sweet potato extract level as a carbohydrate source substrate on the kinetics of fermentation and lactic acid production by Lactobacillus paracasei. Research using L. paracasei , which is a lactic acid bacteria (LAB) collection of the Laboratory of Nutrition Biochemistry of the Faculty of Animal Sciences UGM. Fermentation kinetics were observed with a graph of substrate degradation derived from the Michaelis-Menten equation. Purple sweet potato extract concentration (S) used to determine the value of K m and q max of L. paracasei was 0,01; 0,05 and 0,1%. Purple sweet potato extract concentration (S), which was used for observing the kinetics fermentation and lactic acid production, was ½ K m , K m and 1,5 K m . Observation of substrate degradation was known by conducting the Antrone test. The results of the fermentation kinetics test in the form of slope values, as a parameter of the speed of substrate degradation L. paracasei. Lactic acid production was measured using the Barker and Summerson methods. Analysis data for the value of K m and q max observed descriptively. While, the data of the fermentation kinetics test, pH values and production of lactic acid were analyzed using analysis of variance with a Completely Randomized Design (CRD) in a unidirectional pattern. The addition of purple sweet potato extract to liquid fermentation L. paracasei grading 1,5 K m (3 g/100ml) has shown the optimum pH value and lactic acid production but ½ K m concentration shows higher substrate efficiency.