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The starch in waste bread (WB) from industrial sandwich production was directly converted to ethanol by an amylolytic, ethanologenic thermophile (Parageobacillus thermoglucosidasius strain TM333) under 5 different simultaneous saccharification and fermentation (SSF) regimes. Crude α-amylase from TM333 was used alone or in the presence of amyloglucosidase (AMG), a starch monomerizing enzyme used in industry, with/without prior gelatinisation/liquefaction treatments and P. thermoglucosidasiusTM333 fermentation compared with Saccharomyces cerevisiae as a control. Results suggest that TM333 can ferment WB using SSF with yields of 94-100% of theoretical (based on all sugars in WB) in 48h without the need for AMG addition or any form of heat pre-treatment. This indicates that TM333 can transport and ferment all of the malto-oligosaccharides generated by its α-amylase. In the yeast control experiments, addition of AMG together with the crude α-amylase was necessary for full fermentation over the same time period. This suggests that industrial fermentation of WB starch to bio-ethanol or other products using an enhanced amylolytic P. thermoglucosidasius strain could offer significant cost savings compared to alternatives requiring enzyme supplementation.

The starch in waste bread (WB) from industrial sandwich production was directly converted to ethanol by an amylolytic, ethanologenic thermophile (Parageobacillus thermoglucosidasius strain TM333) under 5 different simultaneous saccharification and fermentation (SSF) regimes. Crude α-amylase from TM333 was used alone or in the presence of amyloglucosidase (AMG), a starch monomerizing enzyme used in industry, with/without prior gelatinisation/liquefaction treatments and P. thermoglucosidasius TM333 fermentation compared with Saccharomyces cerevisiae as a control. Results suggest that TM333 can ferment WB using SSF with yields of 94–100% of theoretical (based on all sugars in WB) in 48 h without the need for AMG addition or any form of heat pre-treatment. This indicates that TM333 can transport and ferment all of the malto-oligosaccharides generated by its α-amylase. In the yeast control experiments, addition of AMG together with the crude α-amylase was necessary for full fermentation over the same time period. This suggests that industrial fermentation of WB starch to bio-ethanol or other products using an enhanced amylolytic P. thermoglucosidasius strain could offer significant cost savings compared to alternatives requiring enzyme supplementation.

Microbial hydrolytic enzymes are relevant biotechnological products that can be applied in various industries. In this study, we have tested the activity of hydrolytic enzymes of a newly isolated Hymenobacter sp. CKS3 strain and showed, for the first time, that members of Hymenobacter genus have still unexplored hydrolytic potential. Crude hydrolytic enzymes, produced by the strain CKS3 on a waste medium, were incorporated into a process of bioethanol production using waste bread. The conditions for bread hydrolysis were optimized using statistical design. Waste bread hydrolysate obtained under optimal conditions (100.73 h of hydrolysis, waste bread concentration 20.36% and agitation speed 200 rpm) contained 19.89 g/l of reducing sugars. A high performance liquid chromatography of hydrolyzed waste bread samples showed that the main components of the hydrolysate were dextrins, maltotriose, maltose and glucose. When using this substrate and waste baker’s yeast for ethanol production under non-optimized conditions 1.73% of ethanol was produced. The results of this study showed that a newly isolated Hymenobacter sp. CKS3 can be utilized for enzymatic hydrolysis and bioethanol production in a process relying on waste materials. Furthermore, it was demonstrated that members of Hymenobacter genus have a significant and currently unexplored potential for bio-based industrial applications.

This article focuses on the use of a rule-based Mamdani-type fuzzy expert system for the prediction of Pmax, HRRmax, ID, and CD as combustion parameters, BTE and BSFC as engine performance parameters, and CO, CO2, HC, and NOx as exhaust emission parameters of fuel blends formed by blending waste bread bioethanol with gasoline in different proportions. For modeling of 55 test conditions created by being operated test engine with 11 different test fuels under five different engine loads. As a result of the study, while combustion parameters were predicted with correlation coefficients in the range of 0.948–0.973% for waste bread bioethanol-gasoline blends, correlation coefficients for engine performance and exhaust emission parameters were in the range of 0.968–0.977% and 0.955–0.991% respectively. Similarly, the ranges of correlation coefficients obtained for sugar beet bioethanol-gasoline blends with fuzzy expert system were as follows: 0.967–0.971% for engine performance parameters, 0.955–0.978% for exhaust emission parameters, and 0.951–0.964% for combustion parameters. These results prove that costly and labor-intensive engine tests can be predicted with minimum effort and high accuracy with the developed model.

Atık ekmekleri değerlendirmek ve toplam ürünmaliyetini azaltmak için karbon kaynağı olarak atık ekmek hidrolizatınınkullanılmasıyla çeşitli Xanthomonas türleritarafından üretilen ksantan gamların sulu çözeltilerinin teknolojik özellikleriincenlenmiş ve ticari ksantan gam ile karşılaştırılmıştır. E n yüksek su tutma kapasitesi ticariksantan gamda tespit edilirken, yağ tutma kapasitesinin X. campestris DSM 19000 and X.axonopodis pv. begoniae tarafındanüretilen gamlarda ticari gamdan daha yüksek olduğu saptanmıştır. Üretilengamlarla puding örnekleri hazırlanmıştır ve Ostwald de Waele modeline görepudinglerin davranışı başarıyla tanımlanmıştır. En yüksek K değeri gam ilaveedilmeyen örneklerde 161.2Pa.sn olarak elde edilmiş olup bunu sırasıyla X. axonopodis pv.begoniaeve X. hortorum pv.pelargonii tarafından üretilen gamlarınilave edildiği örnekler 139.3 Pa.sn ve 133.2 Pa.sndeğerleri ile takip etmiştir. n değerleri 0,12 ile 0,49 arasında değişmiş olupgam ilavesi ile artmıştır. Sonuç olarak bu çalışma, X.axonopodispv. begoniae ve X.hortorum pv. pelargonii izolatları tarafından,substrat olarak atıkekmeğin kullanılmasıyla üretilen gamlarla hazırlanan pudingörneklerinin açısal frekansa ve kayma hızına daha dayanıklı olduğu ve buörneklerin daha sağlam bir jel yapısına sahip olduğunu göstermiştir., Technological properties of aqueous solutions ofxanthan gums produced by various Xanthomonasspecies using waste bread (WB) hydrolyzate as a carbon source to reduce theoverall product cost and to utilize waste bread were investigatedand compared with commercial xanthan gum. While the highest waterholding capacity was detected in the commercial xanthan gum, oil holdingcapacity was higher in xanthan gums from X. campestris DSM 19000 and X. axonopodis pv. begoniae than commercial gum. Pudding samples were prepared by thegums obtained and Ostwald de Waele model was successfully described thebehavior. The highest K value were obtained by the sample without gum addition as 161.2 Pa.sn,this was followed by the sample with the gum from X. axonopodis pv.begoniaewith 139.3 Pa.sn and X.hortorum pv.pelargonii with 133.2Pa.sn . n values varied between 0.12 and 0.49 and increased with theaddition of the gum. Therefore,this study showed that thepudding samples prepared with the gums from X. axonopodis pv. begoniae and X. hortorum pv. pelargonii isolates using waste bread as substrate werefound to be more resistant to shear rate and angular frequency and had a morerobust gel structure.

This study was undertaken to investigate the effect of temperature (25 °C and 30 °C) and nitrogen supplementation (with 20 g/L peptone or without) on bioethanol production from waste bread, waterme...

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∙L1. 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.

The potential of bioH 2 production using waste bread via a two-stage process was examined. In the first stage, the waste bread was utilized by Aspergillus awamori and Aspergillus oryzae through solid state fermentation to generate glucoamylase and protease which were then utilized to hydrolyze the waste bread to produce the waste bread hydrolysate. The highest starch conversion of 96.6% and glucose yield of 0.521 g glucose/g waste bread were achieved within 24 h. In the second stage, the waste bread hydrolysate was utilized for bioH 2 production by Biohydrogenbacterium R3. The maximum H 2 yield of 103 mL H 2 /g waste bread could be obtained. The proposed two-stage bioprocess, which was able to increase the nutrient conversion efficiency and H 2 production from organic solid wastes, should be a promising way for bioH 2 production in industrial application.

Development of bioprocess routes for production of value-added materials from food waste is very attractive in terms of bioprocess economics and environmental protection. in this study, production of 2-keto-d-gluconic acid, a significant platform chemical, from food waste was performed by Pseudomonas reptilivora NRRL B-6 for the first time. the nitrogen source preference of the strain for 2-keto-d-gluconic acid production under different glucose concentrations in synthetic medium has been elucidated. At higher glucose concentrations, utilization of organic nitrogen source (yeast extract) led to higher product formation while at lower glucose concentration, utilization of inorganic nitrogen source (ammonium chloride) was also very feasible. the results indicated that favorable nitrogen source for 2-keto-d-gluconic acid production can change depending on the glucose concentration. the waste bread hydrolysate (glucose 181.43 g/L, protein 1.21% (w/v)) prepared by sequential application of alpha -amylase, amyloglucosidase, and protease was utilized in medium formulation at different glucose concentrations. Bread hydrolysate without additional supplements provided higher product formation than the optimum medium prepared with the hydrolysate. Utilization of 50 g/L CaCO3 led the maximum product formation. the maximum 2-keto-d-gluconic acid production from waste bread was 142.81 g/L with the productivity of 3.02 g/L/h and molar yield of 0.95. the proposed approach in this study confirms that waste bread as a sole source of nutrients can be valorized for microbial production of various industrially relevant platform chemicals., Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK), The postdoctoral fellowship from"The Scientific and Technological Research Council of Turkey (TUBITAK)" has been gratefully acknowledged (S. Yegin).

Bu tez çalışmasında, atık ekmek biyoetanolü-benzin karışımları (E5e, E10e, E15e, E85e, E100e) ve şeker pancarı biyoetanolü-benzin karışımları (E5, E10, E15, E85, E100) tek silindirli, dört zamanlı bir buji ateşlemeli motorda test edilmiştir. Motor testleri sıkıştırma oranı 7 ve ateşleme avansı -25 °KMA ve maksimum tork devri olan 2500 rpm'de farklı motor yüklerinde (2, 2.5, 3, 3.5, 4Nm) gerçekleştirilmiştir. Yakıt karışımları benzinle karşılaştırmalı biçimde yanma davranışı, motor performansı, egzoz emisyonları, termodinamik ve termoekonomik analizler açısından değerlendirilmiştir. Yanma analizi, biyoetanol ilaveli yakıtların genellikle benzine nazaran daha düşük silindir basınçları ve daha yüksek ısı salım hızlarına neden olduğunu göstermiştir. Termal verim maksimum değerlerini motorun 4 Nm yük altında E0, E100 ve E100e (sırasıyla %13.2, %17.1 ve %16.1) yakıtları ile çalıştırılması durumunda almıştır. Her iki biyoetanolün benzine ilavesinin egzoz emisyonları bakımından yüksek O2, CO2, NOx ve düşük CO, HC salımına neden olduğu görülmüştür. Şeker pancarı ve atık ekmek biyoetanolü ilaveli yakıtlar kendi aralarında değerlendirildiğinde, termodinamik açıdan hem kayıp akımlarının daha az olması hem de yakıt enerjisinin ve yakıt ekserjisinin fren gücüne dönüşme oranının fazla olması bakımından en optimum iki yakıtın E100 ve E100e olduğu tespit edilmiştir. E100 için benzine kıyasla %8.13 daha az olan yakıt maliyeti, E100e için %21.57 oranı ile belirgin şekilde artmıştr., In this thesis, waste bread bioethanol-gasoline blends (E5e, E10e, E15e, E85e, E100e) and sugar beet bioethanol-gasoline blends (E5, E10, E15, E85, E100) were tested in a single-cylinder, four-stroke spark ignition engine. Engine tests were carried out at different engine loads (2, 2.5, 3, 3.5, 4Nm) while the compression ratio was 7 and the ignition advance was -25 ° KMA and engine speed was 2500 rpm, corresponding to the maximum torque. Fuel blends were evaluated in terms of combustion behavior, engine performance, exhaust emissions, thermodynamic and thermoeconomic analysis in comparison with gasoline. Combustion analysis has shown that fuels with added bioethanol generally cause lower cylinder pressures and higher heat release rates than gasoline. Thermal efficiency has taken its maximum values when the engine is operated under 4 Nm load with E0, E100 and E100e (13.2%, 17.1% and 16.1% respectively). The addition of both bioethanol to gasoline has been shown to cause high O2, CO2, NOx and low CO, HC emissions in terms of exhaust emissions. Thermodynamically, it is determined that the most optimum fuels are E100 and E100e in terms of having less loss rates and high rate of conversion of fuel energy and exergy to brake power when sugar beet bioethanol and waste bread bioethanol supplemented fuels are evaluated among themselves. The fuel cost, which was 8.13% lower for E100 compared to gasoline, increased significantly with 21.57% for E100e.

The objective of this study was to purify and characterize the α-amylase for industrial perspective. The production of α-amylase through solid-state fermentation by Ganoderma tsuage was investigated by using waste bread as substrates. Production parameters were optimized as 2 mL of inoculum size, moisture 50%, additional carbon source (glucose) and nitrogen source (ammonium nitrate) 10:1, 1 mM/mL MgSO4, 0.75 mM/mL CaCl2 and 0.50 mM/mL KH2PO4. The purification value of α-amylase was observed as 1.2 fold with specific activity of 112 U/mg having a yield of 22%. Specific activity of α-amylase increased up to the level of 143 U/mg and had 1.5-fold purification factor having a yield of 6% after Sephadex gel filtration. Optimum value of α-amylase was obtained at 35°C and at pH 6 for the time duration of 72 h. The Km and Vmax values for α-amylase were 1.3 mg and 39 mg/min, respectively. Calcium chloride (CaCl2) was found to increase the activity of α-amylase while all other compounds seemed to have inhibitory action against α-amylase. Silver nitrate (AgNO3) was the strongest inhibitor and therefore would not be advised for use in future research against α-amylase production.Keywords: α-Amylase, purification, characterization, waste bread, Ganoderma tsuage

In this study, fuel properties of two bioethanol fuel, one produced from waste bread (E100b) and the other originated from sugar beet (E100) and base gasoline (E0) were treat as a subject. It was investigated that the properties of fuel blends formed by mixing both bioethanol with gasoline in the same proportions as 5, 10, 15, 85%. The evaluation was based on the fuel properties, which are thought to have the most influence on engine operation, such as density, purity, kinematic viscosity, octane number, heating value. Waste bread based- bioethanol has been found to cause an increasing effect on the density, kinematic viscosity, while decreasing the heating value to some extent. The results showed that differences in fuel properties among both bioethanol that are thought to be related to purity can be ignored for fuel blends with low bioethanol content.

Food-grade waste and side streams should be strictly kept in food use in order to achieve sustainable food systems. At present, the baking industry creates food-grade waste as excess and deformed products that are mainly utilized for non-food uses, such as bioethanol production. The purpose of this study was therefore to explore the potential of waste wheat bread recycling for fresh wheat bread production. Waste bread recycling was assessed without further processing or after tailored fermentation with lactic acid bacteria producing either dextran or β-glucan exopolysaccharides. When non-treated waste bread slurry was added to new bread dough, bread quality (specific volume and softness) decreased with increasing content of waste bread addition. In situ EPS-production (dextran and microbial β-glucan) significantly increased waste bread slurry viscosity and yielded residual fructose or glucose that could effectively replace the sugar added for yeast leavening. Furthermore, fermentation acidified waste bread matrix, thus improving the hygienic safety of the process. Bread containing dextran synthesized in situ by Weissella confusa A16 showed good technological quality. The produced dextran compensated the adverse effect of recycled bread on new bread quality attributes by 12% increase in bread specific volume and 37% decrease in crumb hardness. In this study, a positive technological outcome of the bread containing microbial β-glucan was not detected. The waste bread fermented by W. confusa A16 containing dextran appears to enable safe bread recycling with low acidity and minimal quality loss.

Bu çalışmada atık ekmek, kavun ve karpuzun biyoetanol üretimineuygunluğu araştırılmıştır. Bayat ekmek tozu, üç farklı enzim dozu ile (0.25, 0.38 ve0.5 mL kg-1) termostabil α-amilaz ve glikoamilaz kullanılarak sıvılaştırıldı vesakkarize edildi. En yüksek şeker 125.35 g L-1, 69.3 DE ve %76.02 nişasta-şekerdönüşüm oranı ile 0.5 mL kg-1 enzim dozajında elde edildi. 1 gram bayat ekmektenen yüksek 0.226 gram şeker elde edildi. Etanol fermantasyonunu optimize etmekamacıyla, denemeler iki farklı sıcaklıkta (25°C ve 30 °C), pepton ilaveli ve ilavesizolmak üzere pH 5.5 ve 150 rpm'de Saccharomyces cerevisiae aktif kuru mayasıkullanarak gerçekleştirildi. Tek yönlü ANOVA, üç hammadde arasında etanolverimi bakımından istatistiksel olarak önemli bir fark olmadığını göstermiştir (p =0.38). Benzer şekilde azot ilavesinin de etanol verimine etkisi istatistiksel olarakönemli bulunmamıştır. Azot ilave edilmeyen atık ekmek hidrozilatı, kavun karpuzsuyu fermantasyonlarında elde edilen etanol verimleri sırasıyla, 0.490, 0.451 ve0.475 g/g şeker olarak bulunmuştur. Aynı hammaddelere azot ilavesi ile elde edilenetanol verimleri sırasıyla 0.497, 0.471 and 0.509 g/g şeker şeklinde olmuştur. In this study waste bread, watermelon, and muskmelon feedstocks wereinvestigated for bioethanol production. Waste bread was liquefied and saccharifiedby thermostable α-amylase and glucoamylase using 0.25, 0.38, and 0.5 mL kg-1enzyme doses. 0.5 mL kg-1 enzyme dose yielded maximum DE 69.3, and 76.02%starch to sugars conversion efficiency, and per gram of waste bread yielded 0.226gram of sugars on a dry mass basis. Bioethanol fermentations were performed attwo different temperatures (25 and 30°C) and with and without nitrogensupplementation at pH 5.5, by Saccharomyces cerevisiae. One-way ANOVAamong all three feedstocks resulted in statistically non-significant differences onethanol yield (p = 0.38). Similarly, there were no significant differences betweenthe groups with respect to nitrogen supplementation. The ethanol yields on wastebread hydrolysate, watermelon and muskmelon without nitrogen supplementationat 30°C were found to be 0.490, 0.451 and 0.475 g/g sugar, respectively. Thosewith nitrogen supplementation were 0.497, 0.471 and 0.509 g/g sugar, respectively.Fermentation at 30°C yielded higher ethanol yield than at 25°C. 97

Biohydrogen production from waste bread in a continuous stirred tank reactor (CSTR) was techno-economically assessed. The treating capacity of the H2-producing plant was assumed to be 2 ton waste bread per day with lifetime of 10years. Aspen Plus was used to simulate the mass and energy balance of the plant. The total capital investment (TCI), total annual production cost (TAPC) and annual revenue of the plant were USD931020, USD299746/year and USD639920/year, respectively. The unit hydrogen production cost was USD1.34/m3 H2 (or USD14.89/kg H2). The payback period and net present value (NPV) of the plant were 4.8years and USD1266654, respectively. Hydrogen price and operators cost were the most important variables on the NPV. It was concluded that biohydrogen production from waste bread in the CSTR was feasible for practical application.

In this study, continuous biohydrogen production from waste bread by anaerobic sludge was performed. The waste bread was first hydrolyzed by the crude enzymes which were generated by Aspergillus awamori and Aspergillus oryzae via solid-state fermentation. It was observed that 49.78g/L glucose and 284.12mg/L free amino nitrogen could be produced with waste bread mass ratio of 15% (w/v). The waste bread hydrolysate was then used for biohydrogen production by anaerobic sludge in a continuous stirred tank reactor (CSTR). The optimal hydrogen production rate of 7.4L/(Ld) was achieved at chemical oxygen demand (COD) of 6000mg/L. According to the results obtained from this study, 1g waste bread could generate 0.332g glucose which could be further utilized to produce 109.5mL hydrogen. This is the first study which reports continuous biohydrogen production from waste bread by anaerobic sludge.