Download full-text PDF. An optimization of biomass produced during baker's yeast production is presented. Context of baker's yeast production process. Download PDF. Concentrations and have been reported for the production of yeast biomass from. With a computer using Maxima 820 software.
Journal of Scientific & Industrial Research Vol. 65, January 2006, pp.
72-76 Baker’s yeast production under fed batch culture from apple pomace Shashi Bhushan1 and V K Joshi2,* 1 Institute of Himalyan Bioresource Technology, CSIR, Palampur 176 061 Department of Postharvest Technology, Dr Y S Parmar University of Horticulture and Forestry, Nauni-Solan, 173 230 Received 31 December 2004; revised 30 September 2005; accepted 10 October 2005 2 Apple pomace extract (APE) in aerobic variable fed batch culture under standardized fermentation parameters was evaluated for the production of baker’s yeast. The substrate was fed at a flow rate of 0.39 dm3 h-1 to regulate fermentable sugar concentration between 1-2% in bioreactor. An average specific growth rate of 0.24 h-1 and cellular yield coefficient of 0.48 g/g sugar was obtained during baker’s yeast production. Under variable fed batch aerobic baker’s yeast fermentation, yield obtained with APE was 96% to that of expected theoretical yield and thus, qualified as an alternative to molasses, the traditional baker’s yeast production carbon source. The dough raising capacity of experimentally produced yeast cells revealed no apparent difference from that of commercial sample. Keywords: Aerobic fermentation, Apple pomace extract, Bakery products, Baker’s yeast, Fed batch culture, Molasses, Saccharomyces cerevisiae, Specific growth rate IPC Code: C12N1/18 Introduction Apple pomace (AP), a leftover residue after apple juice extraction, poses a lot of problem of environmental pollution and a loss of nutritive natural wealth1.
High biochemical oxygen demand (BOD, 395-37000) of AP makes it easily vulnerable to fermentation / biodegradation, consequently if not disposed-off immediately, would generate foul smell2,3. The nutritive value of AP rests mainly on its total carbohydrates, crude protein, crude fat, fibres and minerals. AP can be used for the preparation of jam, sauce, soft drinks, animal feed along with direct incorporation in bakery products4-6, besides production of citric acid, ethanol, acetone, butanol and microbial colour7-9. Due to high nutritive value and easy fermentability, it is suitable for the production of baker’s yeast. The fermentable sugar was found enough in apple pomace extract (APE) to support the growth of baker’s yeast along with crude protein contents as well as a few trace elements3,10,11. Besides type and concentration of carbon sources, other factors such as dissolved oxygen (DO) agitation, pH and temperature, are also known to influence the fermentation behaviour and overall biomass production12-15.
The fermentation parameters such as temperature, pH and DO, standardized during earlier __________ *Author for correspondence, investigation16, were employed in the present fermentation. This paper presents the results of substitution of molasses (a traditional substrate) by APE and its effect on the fermentation characteristics such as specific growth rate (SGR), total biomass yield, cellular yield coefficient (CYC) and other related fermentation characteristics. Materials and Methods Apple Pomace Extract (APE) The dried AP, procured from HPMC (Horticultural Produce Processing and Marketing Corporation), Fruit processing unit, Parwanoo (HP), was ground into fine powder, diluted with water in 1:6 ratio and boiled for ½ h before extraction.The boiled material was pressed in hydraulic press and the liquid filled into conical flasks (5 l), was sterilized at 121°C for 20 min. Download Software Rock Away Riddim Rar Adventurer Six-speed Folding Bike Owners Manual more. more. Inoculum Preserved slant of commercial baker’s yeast (Saccharomyces cerevisiae var. Diastatic) was used to inoculate in yeast malt extract broth and incubated at 30°C for 24 h and then, transferred to APE medium and again incubated at the same temperature for another 24 h. Inoculum (102-103 cells/ml) was added at the rate of 1 percent to initiate the fermentation. BHUSHAN & JOSHI: BAKER’S YEAST PRODUCTION UNDER FED BATCH CULTURE FROM APPLE POMACE 73 Fermentation Kinetics Fermentation kinetics parameters (SGR, CYC and total biomass) were determined20,21, whereas generation time was calculated22.