Optimization of Acetic Acid Fermentation for Producing Vinegar from Extract of Jujube (Zizyphus jujuba Mill.) Fruits

Abstract

The optimum conditions for producing vinegar from Jujube (ziziphus jujuba) juice using Acetobacter aceti were exploited by employing the response surface methodology (RSM). In addition to the initial concentration of ethanol, which is known to be a significant factor affecting acetic acid fermentation, the effects of initial concentration of Jujube juice, A. aceti concentration, pH, and temperature on acetic acid fermentation were also investigated. Out of these factors, the effects of the initial concentration of jujube juice and inoculation amount of A. aceti were determined to be negligible based on statistical analysis. By employing the face-centered experimental design in RSM, the optimum conditions for acetic acid fermentation were exploited for achieving maximum acidity and acetic acid production. The coefficients (R 2 ) of the derived equations from the response surface regression were 0.71 and 0.78 for acidity and acetic acid production, respectively. The maximum production of acetic acid was expected to be 52.76 mg/mL from 25% jujube extract at 21.75 o C with 7.69% alcohol content.

Prediction of vinegar processing parameters with chemometric modelling of spectroscopic data

“…Spectroscopic methods have been also applied to predict the chemical compositional parameters of different types of food products. There are studies in literature which monitored the critical compositional parameters such as total acidity, sugar, acetic acid and ethanol contents at different stages of vinegar production and minor components such as volatiles, phenolic profile and total phenol content were also determined throughout fermentation processes [2,7,15,37]. Spectral data evaluated with chemometric techniques allow the simultaneous estimation of the concentrations of chemical constituents of different types of fermented food products [4,10,9,11,19].…”

Total Polyphenolic, Flavonoid Contents and Antioxidant Capacity of Homemade Kara Sakı Apple Vinegar Produced by Traditional Method Using Different Yeast Materials

“…It has been determined in the studies that the antioxidant activity values of vinegars gained from assorted crude materials vary, the antioxidant activity of pepper leaf vinegar is 92.2%, and the antioxidant capacity contribution of traditional grape vinegars varies between 4.93% and 89.53%, while the antioxidant activity of traditional apple vinegar is 92.2%. It was determined that it contains an effect between 0.53 and 68.89%(Song et al, 2014;Öztürk et al, 2015) Jo et al (2015). determined the total phenolic content in grape vinegar as 84.15 mg GAE/100 mL, and remarked that the antioxidant activity value of the samples was related to the phenolic content of the samples and this value was 61.20% in grape vinegar Alak (2015),.…”