Ethanol fermentation of waste bread using granular starch hydrolyzing enzyme: Effect of raw material pretreatment

Pietrzak, Witold; Kawa-Rygielska, Joanna

doi:10.1016/j.fuel.2014.05.081

Cited by 62 publications

(27 citation statements)

References 29 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…waste breads, waste potato chips, flour hydrolysates, cassava hydrolysates, etc.) represents an interesting option . In some of the above‐mentioned cases, interesting concentrations of ethanol and comparable with the ones reported during first‐generation bioprocess have been reported (e.g.…”

Section: Technology Of Alcoholic Fermentationsupporting

confidence: 73%

Biotechnological production of ethanol: Biochemistry, processes and technologies

Sarris

Papanikolaou

2016

Engineering in Life Sciences

130

View full text Add to dashboard Cite

The majority of environmental problems arise from the use of conventional energy sources. The liability of such problems along with the reduction of fossil energy resources has led to the global need for alternative renewable energy sources. Using renewable biofuels as energy sources is of remarkable and continuously growing importance. Producing bioethanol through conversion of waste and residual biomass can be a viable and important perspective. In the first part of this review, general concepts, approaches and considerations concerning the utilization of the most important liquid biofuels, namely biodiesel and bioethanol, are presented. Unlike biodiesel (specifically first generation biodiesel), the production of bioethanol is exclusively based on the utilization of microbial technology and fermentation engineering. In the second part of this review, the biochemistry of ethanol production, with regards to the use of hexoses, pentoses or glycerol as carbon sources, is presented and critically discussed. Differences in the glycolytic pathways between the major ethanol‐producing strains (Saccharomyces cerevisiae and Zymomonas mobilis) are presented. Regulation between respiration and fermentation in ethanol‐producing yeasts, viz. effects “Pasteur”, “Crabtree”, “Kluyver” and “Custers”, is discussed. Xylose and glycerol catabolism related with bioethanol production is also depicted and commented. The technology of the fermentation is presented along with a detailed illustration of the substrates used in the process and in pretreatment of lignocellulosic biomass, and the various fermentation configurations employed (separate hydrolysis and fermentation, simultaneous saccharification and fermentation, simultaneous saccharification and co‐fermentation and consolidated bioprocessing). Finally, the production of bioethanol under non‐aseptic conditions is presented and discussed.

show abstract

Section: Technology Of Alcoholic Fermentationsupporting

confidence: 73%

Biotechnological production of ethanol: Biochemistry, processes and technologies

Sarris

Papanikolaou

2016

Engineering in Life Sciences

130

View full text Add to dashboard Cite

show abstract

“…Almost all the not consumed bread is disposed as waste, while a little part is re-used as feed. Nevertheless, over the last decade, many researchers attempted to find recycle alternatives: wasted bread was proposed as substrate to produce, through microbial fermentation, chemicals for pharmaceutical or food industries (Oda et al, 1997;Leung et al, 2012), biofuels (Doi et al, 2009;Pietrzak and Kawa-Rygielska, 2014), or enzymes (Asghar et al, 2002;Cerda et al, 2016). All the proposed strategies can potentially reduce the organic matter disposal into the environment, but none of these completely repay the huge economical loss.…”

Section: Introductionmentioning

confidence: 99%

Wasted Bread as Substrate for the Cultivation of Starters for the Food Industry

Verni

Minisci²,

Convertino³

et al. 2020

Front. Microbiol.

View full text Add to dashboard Cite

The amount of bread wasted daily worldwide, throughout its entire lifecycle, from production to distribution, is estimated to be hundreds of tons, therefore representing both economic and environmental issues. This work aimed at the valorization of wasted bread, setting-up a protocol for obtaining a growth medium to be used for the cultivation of food industry microbial starters. The optimization of the protocol included the set-up of parameters for the hydrolysis of the bread nutrient compounds with proteolytic and amylolytic enzymes and the supplementation with nitrogen and/or carbon sources. The suitability of the optimized medium for the growth of lactic acid bacteria, yeasts and fungi from dairy, bakery, and wine industries was assessed. Lactic acid bacteria growth was strongly affected by the quantity and quality of nitrogen sources employed, while yeasts and fungi growth exceeded that obtained with the reference media commonly employed for their cultivation. Wasted bread medium (WBM) represents a realistic option for the valorization and re-use of bread waste, responding to the modern vision of circular economy.

show abstract

“…More efficient hydrolysis is important to obtain a higher yield of ethanol. (PIETRZAK, W. and KAWA-RYGIELSKA, J., 2014) The objective of this study was to optimise enzymatic hydrolysis of waste bread before ethanol fermentation. Main parameters of optimization were pH and temperature of enzymatic hydrolysis.…”

Section: Introductionmentioning

confidence: 99%

Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

Hudečková¹,

Šupinová²,

Babák³

2017

Acta Univ. Agric. Silvic. Mendelianae Brun.

View full text Add to dashboard Cite

Finding of optimal hydrolysis conditions is important for increasing the yield of saccharides. The higher yield of saccharides is usable for increase of the following fermentation effectivity. In this study optimal conditions (pH and temperature) for amylolytic enzymes were searched. As raw material was used waste bread. Two analytical methods for analysis were used. Efficiency and process of hydrolysis was analysed spectrophotometrically by Somogyi-Nelson method. Final yields of glucose were analysed by HPLC. As raw material was used waste bread from local cafe. Waste bread was pretreated by grinding into small particles. Hydrolysis was performed in 100 mL of 15 % (w/v) waste bread particles in the form of water suspension. Waste bread was hydrolysed by two commercial enzymes. For the liquefaction was used α-amylase (BAN 240 L). The saccharification was performed by glucoamylase (AMG 300 L). Optimal conditions for α-amylase (pH 6; 80 °C) were found. The yield of total sugars was 67.08 g•L -1 (calculated to maltose). As optimal conditions for glucoamylase (pH 4.2; 60 °C) were found. Amount of glucose was 70.28 g•L 1 . The time of waste bread liquefaction was 180 minutes. The time of saccharification was 90 minutes. The results were presented at the conference CECE Junior 2014.

show abstract

Ethanol fermentation of waste bread using granular starch hydrolyzing enzyme: Effect of raw material pretreatment

Cited by 62 publications

References 29 publications

Biotechnological production of ethanol: Biochemistry, processes and technologies

Biotechnological production of ethanol: Biochemistry, processes and technologies

Wasted Bread as Substrate for the Cultivation of Starters for the Food Industry

Optimization of Enzymatic Hydrolysis of Waste Bread before Fermentation

Contact Info

Product

Resources

About