Thymol, an important and advantageous component of many essential oils, has been applied as an antimicrobial agent in animals. To increase the duration of action of this compound in ruminants, it was decided here to prepare a controlled release carrier for thymol. Hydroxy propyl methyl cellulose (HPMC) and ethyl cellulose (EC) were used as the matrix polymer here. Mixtures of thymol with eight ...

We present a decision support system for the fermentation step in winemaking based on a mathematical model of kinetics of alcoholic fermentation. We used an optimization technique in order to predict the fermentation step. This optimization technique was carried out using the method of factorial analysis. The first interesting application of this system, rather than existing ones, comes from th...

Batch fermentation of milk inoculated with lactic acid bacteria was conducted in the presence of hydrotalcite-type anionic clay under static and ultrasonic conditions. An experimental study of the effect of fermentation temperature (t=38-43 °C), clay/milk ratio (R=1-7.5 g/L) and ultrasonic field (ν=0 and 35 kHz) on process dynamics was performed. A mathematical model was selected to describe th...

17-35 ABSTRACT Rumen fermentation kinetics of grass and silage, differing in age and yield (1500 -7900 kg DM ha), were studied in sacco and in vitro, using the gas production test and the Tilley and Terry technique. An increasing yield increased the content of NDF and lignin in grass and decreased protein content, in vitro degradability measured by the Tilley and Terry method, and rate of ferme...

The conversion of glycerol to 1,3-propanediol (1,3-PD) by Clostridium acetobutylicum ATCC 4259 was studied in an anaerobic culture using commercial glycerol as the sole carbon source. The objective of this study was to determine the best concentration of glycerol used for the production of 1,3-propanediol and to study the cell growth kinetics of Clostridium acetobutylicum ATCC 4259 using fermen...

This paper deals with the design of a feedback controller for fed-batch microbial conversion processes that forces the substrate concentration C(S) to a desired setpoint, starting from an arbitrary (initial) substrate concentration when non-monotonic growth kinetics apply. This problem is representative for a lot of industrial fermentation processes, with the baker's yeast fermentation as a wel...

Direct fermentation of 226 white rose tapioca stem to ethanol by Fusarium oxysporum was studied in a batch reactor. Fermentation of ethanol can be achieved by sequential pretreatment using dilute acid and dilute alkali solutions using 100 mesh tapioca stem particles. The quantitative effects of substrate concentration, pH and temperature on ethanol concentration were optimized using a full fact...

Product quality and productivity improvement of a fermentation process implies, usually, reliable online measurements. Due to the difficulties, high costs and inefficient technology to obtain on-line measurements, several methodologies were developed to overcome these problems. In this work, algorithms for on-line state observation and kinetics parameters estimation applied to fed-batch baker’s...

The study was designed to determine the effect of a candidate natural feed additive on kinetics gas production as representation degradability and methane produced during rumen fermentation. Three blends essential oil (BEO) candidates for additives were formulated using pine eucalyptus oils in following ratios: 75:25, 50:50, 25:75 BEO1, BEO2, BEO3, respectively. Every BEO added batch fermentati...