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A recent trend in sustainable bioethanol production is the use of agricultural waste or food waste as an inexpensive and the most available feedstock. Bread waste is the major food waste that could be successfully used for the production of bioethanol. The aim of this study was to optimize ethanol production by the response surface methodology (RSM) using waste bread hydrolysate. Waste bread hydrolysate was obtained using crude hydrolytic enzymes that produce bacterial isolate Hymenobacter sp. CKS3. The influence of time of fermentation (24?72 h) and waste brewer?s yeast inoculum (1?4 %) on ethanol production was studied. The optimal conditions, obtained by central composite design (CCD), were 48.6 h of fermentation and 2.85 % of inoculum. Under these conditions, a maximum of 2.06 % of ethanol concentration was reached. The obtained ethanol concentration was in good correlation, coefficient of 0.858, with yeast cell yield. The results obtained in this study imply that waste bread hydrolysate could be used as a biomass source for biofuel production with multiple benefits relating to environmental protection, reduction of production costs, and saving fossil fuels.

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.

Food-grade enzymes (alpha-amylase, amyloglucosidase, maltogenic amylase, and protease) were investigated for recycling waste bread back to wheat bread-making process. Waste bread was efficiently hydrolyzed into sugars (up to 93% glucose yield) and the best combination of enzymes was alpha-amylase (0.05 g/kg bread) and amyloglucosidase (2.5 g/kg bread). Selected enzyme hydrolysis processes were tested in wheat bread making as a (a) hydrolyzed slurry, that is hydrolyzed waste bread without solid/liquid separation and (b) syrup, that is liquid supernatant after centrifugation of the hydrolyzed waste bread. Both hydrolyzed bread slurry and syrup were successfully utilized to replace sucrose (2 and 4%) in bread making without affecting the bread quality when compared to the control bread. Techno-economic assessment revealed that this approach is 12% more economical than the current mean to dispose the bakery waste. This recycling concept showed both technical and economic potential for bakery industries to overcome their excess bread production. Novelty impact statement A new recycling process was developed by using enzymes to efficiently hydrolyze surplus bread into sugars. The use of those sugar-rich slurries and syrups in bread rework did not affect the bread quality when compared to the control bread. The recycling concept was more economical than current means to dispose waste bread, revealing the technical and economic potential for bakery industries to overcome their excess bread production.

Waste streams from ethanol and bread production present inexpensive, abundant and underutilized renewable substrates that are highly available for valorisation into high-value products. A combined submerged to solid state fermentation strategy was studied using the edible filamentous fungus Neurospora intermedia to biotransform ethanol plant residues ‘thin stillage’ and waste bread as substrates for the production of additional ethanol, biomass and a feed product rich in pigment. The fungus was able to degrade the stillage during submerged fermentation, producing 81 kg ethanol and 65 kg fungal biomass per ton dry weight of thin stillage. Concurrently, the second solid state fermentation step increased the protein content in waste bread by 161%. Additionally, 1.2 kg pigment per ton waste bread was obtained at the best conditions (6 days solid state fermentation under light at 95% relative humidity at 35 °C with an initial substrate moisture content of 40% using washed fungal biomass to initiate fermentation). This study presents a means of increasing the value of waste bread while reducing the treatment load on thin stillage in ethanol plants.

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.

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.

Simultaneous dark fermentative hydrogen and ethanol production from waste bread in a mixed packed tank reactor (MPTR) was investigated. Waste bread was first hydrolyzed by the produced enzymes to generate the waste bread hydrolysate which was subsequently introduced to the MPTR for dark fermentative hydrogen and ethanol production. The optimal hydrogen and ethanol production rates were 15.01 mmol/(h·L) and 23.25 mmol/(h·L) when the organic loading rate reached 32 g/(L·d). The unit hydrogen and ethanol production were 4.87 mmol hydrogen/g waste bread and 7.54 mmol ethanol/g waste bread, respectively. This study provided a new direction for economic and efficient hydrogen and ethanol production from waste bread.

Amongst the many forms of food waste, bread is a major contributor to the problem. Two aims of this research investigate waste breads potential of being a bioresource for the production of fermentable sugars which are precursor of valuable bioproducts by fermentation process: finding optimum substrate, water and enzyme ratio to produce the highest amount of fermentable sugars and investigating the rheological behavior of the system during hydrolysis. Two stage waste bread hydrolysis was performed with enzymes alpha-amylase and amyloglucosiades and response surface methodology was used to optimize substrate, water and enzyme ratio. Discovery Hybrid Rheometer-2 (TA Instruments) fitted with a parallel-plate geometry was used to investigate steady flow viscosity of the slurry during hydrolysis. 99 % of theoretical maximum glucose yield, a main fermentable sugar, is achieved by optimizing enzymatic hydrolysis conditions of waste bread at liquefaction and saccharification stages. Just after the addition of alpha-amylase enzyme, substantial decrease is observed in viscosity and Casson apparent yield stress of the slurry. During saccharification stage, glucose yield increases dramatically while viscosity of the slurries is very low and does not change considerably. The results imply that utilizing high concentrations of waste bread as a feedstock to produce fermentation products offers economic benefits without causing high power consumption, excessive wear on equipment, and reduced conversion which are generally expected consequences for high-solid processing.

In this paper yields of bioethanol from seven samples of bread were compared. Samples of bread were produced and prepared in a laboratory by mixing wheat and buckwheat flour in amounts of 0, 20, 40, 50, 60, 80 and 100%. At first, the analysis of all seven samples of bread was done (dry matter, starch content and pH value of bread sample suspensions). Then the waste bread suspensions were hydrolyzed by applying commercial hydrolytic enzymes, Termamyl® SC and SAN Extra® L. The fermentation process was carried out with dry instant yeast, Saccharomyces cerevisiae, after which distillation of all fermented suspensions was performed. The ethanol contents in the distillates of all seven samples were determined. The highest yield of bioethanol was detected in the bread sample made of pure wheat flour. The ethanol yield gradually decreased with increasing content of buckwheat flour in bread. These results could be useful when considering the possibility of utilization of waste bread from different sources as a feedstock for bioe­thanol production.

According to the significant role of sugar alcohols (Polyols) in food industries, in the present study the possibility of microbial production of mannitol from bread waste was studied. Microbial growth and amylase production were investigated by five Iranian native strains of Bacillus spp in starch agar and broth. The best strain was selected, and its growth curve was determined. Leuconostoc mesentroides PTCC 1059 was used as a control strain to convert fructose to mannitol. In order to determine the ability of selected strains in converting waste breads into mannitol sugar, a culture medium was prepared from waste of Lavash and Baguette breads. Afterward, the ability to convert starch into fructose by Chemical analysis glucose test was used, and then bio-conversion analysis of fructose to mannitol by HPLC analysis was investigated. HPLC results showed that the Bacillus subtilis and Leuconostoc mesentroides PTCC 1059 had the ability of producing mannitol at a rate of 4.8g/L from fructose 5%, 0.15 g/L from Lavash bread 5%, and 0.2g/L from Baguette bread.

The subject of this research project was assessment of direct starch to ethanol conversion process course of waste wheat-rye bread using granular starch hydrolyzing enzyme (GSHE). Several pretreatment methods (enzymatic prehydrolysis, microwave irradiation, sonification) were used to improve the course of fermentation and were compared with separate hydrolysis and fermentation (SHF). Due to high water binding capacity of raw material fermentations were conducted at a substrate loading of 150 g kg −1 . Only during enzymatic pretreatment and the SHF process the raw material was preliminary liquefied so its higher concentrations could be applied. The dynamics of fermentation was similar in all studied variants. The fermentation of unpretreated waste bread ended with 80.00% ethanol yield (354.36 g kg −1 of raw material). Pretreatment of raw material improved ethanol yield by ca. 3–8%.

The aim of this study was kinetic analysis of the multi-enzyme solution produced from waste bread via solid state fermentation by Aspergillus awamori. It was found that at normal temperature for hydrolysis reactions, 60 °C, the activation energies for denaturation of A. awamori glucoamylase, 176.2 kJ/mol, and protease, 149.9 kJ/mol, are much higher than those for catalysis of bread starch, 46.3 kJ/mol, and protein, 36.8 kJ/mol. Kinetic studies showed that glucoamylase and protease in the multi-enzyme solution should have at least two conformations under the two temperature ranges: 30–55 °C and 60–70 °C. Thermodynamic analysis showed that, deactivation of glucoamylase and protease in the multi-enzyme solution can be reversible between 30 °C and 55 °C, since ΔS is negative and ΔH is positive. On the other hand, for glucoamylase and protease, both ΔS and ΔH are positive between 60 °C and 70 °C. This means that the deactivation of both enzymes in the multi-enzyme solution is spontaneous in this temperature range. It was also found that the glucoamylase produced in the solid state fermentation of waste bread is more thermally stable than the protease in the mixture. Consequently, the protease had little or no effect on the stability of the glucoamylase. Furthermore, the half-life of the glucoamylase produced from waste bread pieces was much higher than that produced from wheat flour. This is an important finding because the mode of production, via solid state fermentation, appears to have increased the thermostability of the enzyme significantly.

When it is not consumed, bread presents a major source of food waste, both in terms of the amount and its economic value. However, bread also possesses the characteristics of an ideal substrate for solid state fermentation. Yet nearly all wasted bread ends up in landfill sites, where it is converted into methane by anaerobic digestion. Governments are finally taking action and, according to the EU Landfill Directive, for example, biodegradable municipal waste disposed into landfills must be decreased to 35% of 1995 levels, by 2020. Solid state fermentation of waste bread for the production of value added products is a novel idea, which could help with the achievement of this target. In this study, glucoamylase and protease production from waste bread pieces, via solid state fermentation, was investigated in detail. The optimum fermentation conditions for enzyme production were evaluated as, 20 mm particle size, 1.8 (w/w, db) initial moisture ratio, and duration of 144 h. Under these conditions, glucoamylase and protease activities reached up to 114.0 and 83.2 U/g bread (db), respectively. This study confirms that waste bread could be successfully utilised as a primary raw material in cereal based biorefineries.

A novel biorefinery concept of utilising waste bread as a sole nutrient source for the production of a nutrient rich feedstock for the fermentative succinic acid production by Actinobacillus succinogenes has been developed. Waste bread was used in the solid-state fermentations of Aspergillus awamori and Aspergillus oryzae that produce enzyme complexes rich in amylolytic and proteolytic enzymes, respectively. The resulting fermentation solids were added directly to a bread suspension to generate a hydrolysate containing over 100 g/L glucose and 490 mg/L free amino nitrogen (FAN). A first-order kinetic model was used to describe the effect of initial bread mass ratio on glucose and FAN profiles. The bread hydrolysate was used as the sole feedstock for A. succinogenes fermentations, which led to the production of 47.3 g/L succinic acid with a yield and productivity of 1.16 g SA/g glucose and 1.12 g/L h. This corresponds to an overall yield of 0.55 g succinic acid per g bread. This is the highest succinic acid yield compared from other food waste-derived media reported to date. The proposed process could be potentially utilised to transform no-value food waste into succinic acid, one of the future platform chemicals of a sustainable chemical industry.

The present study is the first of its kind to use industrial waste bread for ethanol and food-grade filamentous fungal biomass production, with an ‘integrated-biorefinery’ approach for the existing wheat-based ethanol facilities. Four different food-grade fungi such as Neurospora intermedia, Aspergillus oryzae, belonging to ascomycetes and Mucor indicus, Rhizopus oryzae, belonging to zygomycetes, were screened. Initial screening for fungal cultures (without external enzyme saccharification) showed an ethanol yield maximum of 47.8 ±1.1 to 67.3 ±2.1, and 38.7 ±1.1 to 67.7±1.8 mg per g dry substrate loading from whole-grain bread and white-bread respectively, post the enzymatic liquefaction. Scale-up of the N. intermedia fermentation achieved using bench scale airlift reactor showed an ethanol yield maximum of 91.6 ±2.1 and 87.5 ±1.9 mg per g dry substrate loading for whole-grain bread and white-bread respectively.

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.

Besides increasingly important issues with regard to quantity and availability of raw materials together with their properties and quality the feedstock costs are very important for the production of bulk chemicals. Especially for biotechnological processes, in which the carbon of various substrates should be converted into microbial products (e.g. lactic acid), there is an increasing interest in the use of biogenic residues and waste materials. Carbohydrates like starch, which is the main constituent of the bakery waste, are preferably used as substrates/nutrients for several fermentation processes. As part of a European project (BREAD4PLA) we have been carried out different analytical methods for the estimation of parameters which are basically characteristic in terms of the further use as main substrate for lactic acid fermentation processes. The main objective of this research is to show the production of polylactic acid from residual bread in a pre-industrial continuous process. In the sense of a closed loop (organic waste from the bakery industry, fermentative production of lactic acid from remaining bread, polymerization of lactic acid to polylactic acid, PLA modification by compounding and film production as well as final testing and evaluation of these films for packaging), the 100% biodegradable PLA film can subsequently be used for the packaging of fresh baking goods. First results about the potential of waste bread as an alternative substrate source for lactic acid fermentation are presented and discussed.

After selection from eight yeast commercial or type strains based on their aromatic potential to valorize bread by-products, Geotrichum candidum ATCC 62217 formed fruity aroma compounds (pineapple-like) on fermented waste bread (35% white bread crumb and 65% water). Fatty acids esters were identified, including ethyl esters of acetic acid, propionic acid, butyric acid and isobutyric acid. Their production corresponded to the stationary growth phase of the strain and, after 48 h, it was improved by agitation and, to a lesser extent, at 30°C compared to 25 or 20°C. Aromatic properties of the strain were linked to its ability to metabolize organic acids.

When it is not consumed, bread presents a major source of food waste, both in terms of the amount and its economic value. However, bread also possesses the characteristics of an ideal substrate for solid state fermentation. Yet nearly all wasted bread ends up in landfill sites, where it is converted into methane by anaerobic digestion. Governments are finally taking action and, according to the EU Landfill Directive, for example, biodegradable municipal waste disposed into landfills must be decreased to 35% of 1995 levels, by 2020. Solid state fermentation of waste bread for the production of value added products is a novel idea, which could help with the achievement of this target. In this study, glucoamylase and protease production from waste bread pieces, via solid state fermentation, was investigated in detail. The optimum fermentation conditions for enzyme production were evaluated as, 20 mm particle size, 1.8 (w/w, db) initial moisture ratio, and duration of 144h. Under these conditions, glucoamylase and protease activities reached up to 114.0 and 83.2 U/g bread (db), respectively. This study confirms that waste bread could be successfully utilised as a primary raw material in cereal based biorefineries. (C) 2013 The Institution of Chemical Engineers. Published by Elsevier B.V. All rights reserved.

Optimal conditions for sourdough production from waste bread containing sugar were studied. Using a dough prepared with 50% white bread crumb in water instead of 35% crumb, high levels of acidity were formed at 35°C with a commercial lyophilized starter containing Lactobacillus plantarum . The effect of temperature (25 or 35°C) on titratable acidity development was equivalent to crumb concentration (35 or 50%). Cell growth stopped after 12–24 h but acid production continued for more than 48 h. Best results were obtained with whole wheat bread crumb followed by sweet-type crumb (about 8% sugar, dry basis) and white bread crumb. Two commercial sources of Lactobacillus plantarum , one meat starter and one bread starter, were screened based on acid production in fermented bread crumb.

Bread, the staple of the west and, increasingly, the rest of the world, is also one of the most heavily wasted of all food products. Currently, much of this waste is disposed of in landfill sites where it decomposes to methane and carbon dioxide. Yet it is a potentially valuable, renewable resource for the production of chemicals. This chapter explores the opportunities for enhancing the value of this cereal-based waste food through the use of fermentation. Following a review of the literature concerning bread waste utilization, potential process systems are proposed and examined. As bread is a solid raw material, solid state fermentation is preferred as the most efficient means of delivering bioprocesses, and some preliminary optimization studies are presented.

Background: Many species of sustainable mycotoxin-producing fungi are considered as dangerous agents for humans. Bread is one of the materials exposed to fungal infection and molds are amongst the most important pollutant microbial and chemical mycotoxin-producing agents of bread. In this study, the microbial and chemical contamination of recycled waste breads and the types of produced mycotoxins at two areas of Tehran municipality, Iran, were investigated. Methods: Using fungal culture media, twenty samples of waste bread were analyzed for microbial contaminations. To recognize contamination to mycotoxins, high-performance liquid chromatography (HPLC) method and fuorescence detector (FLD) were used. Findings: All but one sample were contaminated to mold infections such as Aspergillus, Penicillium, and yeasts including Geotricum candidum, Candidia albicans and Saccharomyces cerevisiae. Eight samples were contaminated to aflatoxins, ochratoxin A and deoxynivalenol, whereas none of them showed contamination with zearalenone. Conclusion: The results indicated that presence of microbial and toxic contamination in bread waste is inevitable, which is harmful for human health. The sanitary control of food waste to reduce or eliminate microbial hazards in food recycling is necessary.

Aims The aim of this study was to investigate the effectiveness of bread as substrate for γ-aminobutyric acid (GABA) biosynthesis, establishing a valorization strategy for surplus bread, repurposing it within the food chain. Methods and Results Surplus bread was fermented by lactic acid bacteria (LAB) to produce GABA. Pediococcus pentosaceus F01, Levilactobacillus brevis MRS4, Lactiplantibacillus plantarum H64 and C48 were selected among 33 LAB strains for the ability to synthesize GABA. Four fermentation experiments were set up using surplus bread as such, added of amylolytic and proteolytic enzymes, modifying the pH or mixed with wheat bran. Enzyme-treated slurries led to the release of glucose (up to 20 mg g−1) and free amino acid, whereas the addition of wheat bran (30% of bread weight) yielded the highest GABA content (circa 800 mg kg−1 of dry weight) and was the most suitable substrate for LAB growth. The selected slurry was ultimately used as an ingredient in bread making causing an increase in free amino acids. Conclusions Besides the high GABA concentration (148 mg kg−1 dough), the experimental bread developed in this study was characterized by good nutritional properties, highlighting the efficacy of tailored bioprocessing technologies as means to mitigate food wastage. Significance and Impact of Study Our results represent a proof of concept of effective strategies to repurpose food industry side streams.

Surplus bread is a major bakery side stream that should be strictly kept within the human food chain to reduce waste and ensure resource efficiency in baking processes. Optimally, surplus bread should be recycled as a dough ingredient, however, this is known to be detrimental to the volume and texture of bread. The purpose of this study was to investigate how gelatinized starch in surplus bread, untreated or enzymatically hydrolyzed, affects dough development, bread volume and textural attributes. Starch was hydrolyzed to various degrees using commercial alpha-amylase and amyloglucosidase. Bread hydrolysates containing different carbohydrate profiles (untreated, 75%, 57%, and 26% starch remaining) were evaluated as dough ingredients. More complete starch hydrolysis resulted in better dough visco-elastic properties and higher dough level, and reduced dough water absorption by 13%. Nonetheless, breads containing hydrolysate with high-malto-oligosaccharides had the lowest intrinsic hardness and similar volume yield when compared to control bread. Furthermore, compared to untreated slurry, the hydrolysate with high-malto-oligosaccharides, reduced crumb hardness by 28% and staling rate by 42%, and increased specific volume by 8%. The present findings show that enzymatic hydrolysis dramatically transforms the impact of gelatinized starch. Thus, by selecting correct bioprocessing approaches, bread recycling performance may be significantly improved.

Tüm toplumlarda temel besin kaynaklarının başında tahıl ve tahıl ürünleri yer almaktadır. Ekmek de en önemli tahıl ürünü olarak toplam gıda tüketimindeki payı ile önemini korumaktadır. Ekmek, geleneksel olarak beslenme alışkanlığımızda aldığı payın yüksekliği kadar farklılaştırılmış ürünlerin artması, ihtiyaç fazlası satın alma ve israfa konu olması açısından da dikkat çekici bir üründür. Dünyada gıda arz ve fiyatlarında yaşanan dalgalanmalar, gıda güvenliği ve güvenilirliği tartışmalarının gelişmiş ve gelişmekte olan ülkelerde gündemde olması ve ayrıca, iklim değişikliğinin yarattığı baskı altında sürdürülebilirliğin risk altında olması gıda israfı ve bu israfın sosyal, ekonomik ve çevresel etkilerini su yüzüne çıkarmıştır. Türkiyede de gündemde olan ekmek tüketimini, israf boyutu ile ele almayı amaçlayan bu çalışma TR6-Akdeniz Bölgesinde önemli nüfus artışları olan ve göç alan sosyo-ekonomik düzeyleri farklı 3 büyükşehir sınırları içinde 2011 yılında 20 yaş ve üstü kadınlarla gerçekleştirilmiştir. Çalışma, ekmek tüketimine, israfına ve bayat ekmeklerin değerlendirilmesine yönelik tüketici alışkanlıklarını ortaya koymak amacıyla yapılmıştır. Elde edilen sonuçlara göre, yüzde 85 ile en fazla beyaz ekmek tercih edilmektedir. Araştırmaya katılan kadınların kişi başına günlük beyaz ekmek tüketimi 273,38 gr.dır ve alınan ekmeğin %38,2'si israf edilmektedir. Her gün kişi başına ortalama 2 dilim ekmek israf edilmektedir. Bu nedenle yıllık ekonomik kayıp 107 TL/kişi'dir., Grain and grain products, in all societies, are among the most important sources of essential nutrients. Bread is one of the most important cereal products, with a significant share in total food consumption, also remains important. Increased interest in different types of bread leads to purchasing surplus and wasting. Fluctuations in food production and food price contribute to the food security debate both in industrialised countries and the developing countries; besides, sustainability is at risk under the pressure of climate change "food waste" has been discussed in recent years because of the environmental, economic and social impacts it generates. The study was carried out in the 3 metropolitan area with significant population growth, high rate of migration and different socio-economic levels, in Mediterranean region in 2011. The results of the study based on face to face survey data with the women responders which were living in the area and at the age 20 year and older. The purpose of the study is to determine consumers habits on bread consumption, bread waste and altenative use of stale bread. The findings of this study indicate that consumers prefer white bread the most, for those who prefer white bread ratio is 85%. The consumption of white bread per person per day for women participating in the study 273,38 gr. and 38,2 percent of this amount is wasted. Every day an average of 2 slices of bread per person is wasted. Therefore, the annual economic loss is 107 TL/person.

Objective : The study was designed to determine nutrient composition, evaluate physical and organoleptic properties of bread incorporated with abattoir waste (blood meal) as protein and micronutrient fortifier. Methods : Fresh abattoir blood meal was collected from Anyigba abattoir, divided into two equal parts, one part kept frozen until used and the other prepared into powder (6.5% moisture content, 180 micron particle size) and packaged into heat sealed HDPE bag for use. Both liquid and powdered abattoir wastes were each incorporated into bread recipe at four (4) different levels: 5.0%, 7.5%, 10.0% and 12.5% of flour, and then baked into bread loaves, making eight experimental samples plus the control, using standard methods and procedures. The physical characteristics and chemical composition of the bread loaves were determined. Their sensory qualities as well as acceptability were also evaluated. The data obtained were subjected to statistical analysis. Results: Protein contents of experimental bread loaves increased with increase in abattoir waste levels from 8.98% - 13.31%, showing appreciable increase above 6.89% obtainable in conventional bread. Similarly, the range of values for micronutrients content of the experimental bread were: Fe (14.5-23.1 mg /100g), P (24.8-37.8mg/100g) and I2 (0.100-0.261 mg/100g).They also showed significant increases over and above the respective micronutrient contents of traditional bread. There were little or no variations in physical characteristics, except the weight of bread loaves. The crust and crumb colours of bread loaves containing liquid abattoir waste (at 5.0 – 12.5% levels) and powder (at 5.0% level) were more cherished, though significantly different (P

According to the US Department of Energy, succinic acid (SA) is a top platform chemical that can be produced from biomass. Bread waste, which has high starch content, is the second most wasted food in the UK and can serve as a potential low cost feedstock for the production of SA. This work evaluates the environmental performance of a proposed biorefinery concept for SA production by fermentation of waste bread using a cradle-to-factory gate life cycle assessment approach. The performance was assessed in terms of greenhouse gas (GHG) emissions and non-renewable energy use (NREU). Waste bread fermentation demonstrated a better environmental profile compared to the fossil-based system, however, GHG emissions were about 50% higher as compared to processes using other biomass feedstocks such as corn wet mill or sorghum grains. NREU for fermentative SA production using waste bread was significantly lower (~ 46%) than fossil-based system and about the same as that of established biomass-based processes, thus proving the great potential of waste bread as a valuable feedstock for bioproduction of useful chemicals. The results show that steam and heating oil used in the process were the biggest contributors to the NREU and GHG emissions. Sensitivity analyses highlighted the importance of the solid biomass waste generated in the process which can potentially be used as fish feed. The LCA analysis can be used for targeted optimization of SA production from bread waste, thereby enabling the utilization of an otherwise waste stream and leading to the establishment of a circular economy.

İnsanların çoğu ihtiyaç fazlası olan gıdaları değerlendirememekte ve gıdanınönemli bir bölümünü atmaktadır. Ekmeğin aşırı tüketimi gıda israf konusunuönemli kılmaktadır. Öneminden dolayı bu çalışmada ekmek israf etmeme niyetinde etkisiolduğu düşünülen faktörleri değerlendirmek amaçlanmıştır. Anket yöntemininuygulandığı çalışmada Bandırma’da yaşayan 235 kişiye ulaşılarak artan ekmeğideğerlendirme alışkanlıkları ölçülmeye ve israfı önlemede etkisi olan faktörlerbelirlenmeye çalışılmıştır. Sonuçlara göre farkındalık ve alışveriş alışkanlığıdışındaki ahlaki norm, geri dönüşüm alışkanlıkları ve bilgi düzeyi israf etmemeniyetini (önleme) etkilemektedir., Most people are unable to evaluate surplus food and throwing an important part of the food, and lead to food wastage. Considering that hunger is increasing in the world, it is not possible to ignore bread waste. This study aimed to evaluate some factors affecting the intention to not waste bread because of its importance. 235 people living in Bandirma were surveyed by easy sampling. Also, it aimed to determine the factors that have an effect on the intention not to waste. According to the results, the norm, recycling habits and level of knowledge have a significant effect on the intention to not waste bread. On the other hand, awareness and shopping habits have not a significant effect on it. The results of the study are expected to guide businesses and academicians.

In this study, the effect of the flour, which was obtained from stale bread, on flour and bread quality was investigated. The bread that was staled at refrigerator for 7 days was prepared as whole and crumb, and was grinded to convert into flour. The staled whole and crumb bread flours were stored at −18 °C and used to replace 0, 15, 30 and 45% of wheat flour. Then microbiological and physicochemical properties of flours; physical, textural and sensory properties of bread obtained from these composite flours were investigated. We concluded that stale bread flour could be used for bread production at the level of 15%. If the total bread production and consumption is considered, this addition level could provide a significant amount of waste bread recycling each year.

The catalytic activity of engineered biochar was scrutinized for generation of glucose and hydroxymethylfurfural (HMF) from starch-rich food waste (bread, rice, and spaghetti). The biochar catalysts were synthesized by chemical activation of pinewood sawdust with phosphoric acid at 400–600 °C. Higher activation temperatures enhanced the development of porosity and acidity (characterized by C O PO3 and C PO3 surface groups), which imparted higher catalytic activity of H3PO4-activated biochar towards starch hydrolysis and fructose dehydration. Positive correlations were observed between HMF selectivity and ratio of mesopore to micropore volume, and between fructose conversion and total acid density. High yields of glucose (86.5 Cmol% at 150 °C, 20 min) and HMF (30.2 Cmol% at 180 °C, 20 min) were produced from rice starch and bread waste, respectively, over H3PO4-activated biochar. These results highlighted the potential of biochar catalyst in biorefinery as an emerging application of engineered biochar.

In this study, the effect of the flour, which was obtained from stale bread, on flour and bread quality was investigated. The bread that was staled at refrigerator for 7 days was prepared as whole and crumb, and was grinded to convert into flour. The staled whole and crumb bread flours were stored at -18 degrees C and used to replace 0, 15, 30 and 45% of wheat flour. Then microbiological and physicochemical properties of flours; physical, textural and sensory properties of bread obtained from these composite flours were investigated. We concluded that stale bread flour could be used for bread production at the level of 15%. If the total bread production and consumption is considered, this addition level could provide a significant amount of waste bread recycling each year.

Background, aim, and scope: The aim of this study has been to estimate the carbon footprint of bread produced and consumed in the UK. Sliced white and wholemeal bread has been considered for these purposes and the functional unit is defined as "one loaf of sliced bread (800 g) consumed at home". The influence on the carbon footprint of several parameters has been analysed, including country of origin of wheat (UK, Canada, France, Germany, Spain and USA), type of flour (white, brown and wholemeal) and type of packaging (plastic and paper bags). The effect on the results of the type of data (primary and secondary) has also been considered. Materials and methods: The carbon footprint has been estimated in accordance with the PAS 2050 methodology. The results have also been calculated following the ISO 14044 methodology to identify any differences in the two approaches and the results. Primary data for the PAS 2050-compliant study have been collected from a UK bread supply chain. Secondary data have been sourced from the UK statistics, life cycle inventory databases and other published sources. Results and discussion: The carbon footprint results range from 977 to 1,244 g CO2 eq. per loaf of bread. Wholemeal thick-sliced bread packaged in plastic bags has the lowest carbon footprint and white medium-sliced bread in paper bag the highest. The main hot spots are wheat cultivation and consumption of bread (refrigerated storage and toasting), contributing 35% and 25% to the total, respectively. Conclusions: The carbon footprint could be reduced on average by 25% by avoiding toasting and refrigerated storage of bread. Further reductions (5-10%) could be achieved by reducing the amount of waste bread discarded by consumers. The contribution of transport and packaging to the overall results is small. Similar trends in the results are also found in the study based on the secondary data and following the ISO 14044 methodology. © Springer-Verlag 2011.

In traditional cereal-based industrial processes, component separation is often incomplete resulting in a residue of mixed macromolecules including largely starch, protein, phytic acid and many others. The development of a viable cereal-based biorefinery would involve effective bioconversion of cereal components for the production of a nutrient-complete fermentation feedstock. Simultaneous starch and protein hydrolysis represents an effective approach to the production of platform chemicals from wheat. Solid state fermentations of wheat pieces and waste bread by Aspergillus oryzae and Aspergillus awamori have been combined in this study to enhance starch and protein hydrolysis. Kinetic studies confirmed that the proteolytic enzymes from A. oryzae introduced no negative effect on the stability of the amylolytic enzymes from A. awamori under the optimal conditions for starch hydrolysis. When applied to hydrolyse wheat flour, the enzyme solution from A. awamori converted nearly all of the starch into glucose and 23% of the total nitrogen (TN) into free amino nitrogen (FAN). Under the same reaction conditions the enzyme solution from A. oryzae hydrolysed 38% of the protein but only 18.5% of the starch. A mixture of the two enzyme solutions hydrolysed 34.1% of the protein, a 1.5-fold increase from that achieved by the enzyme solution from A. awamori, while maintaining a near completion of starch hydrolysis.

Lactic acid is a significant chemical for the food industry. Fermentative lactic acid production on wastes could significantly improve the economy and sustainability of the process. In this study, lactic acid production was performed by L. rhamnosus ATCC 7469 on a stillage from bioethanol production on waste bread. Under optimal conditions, in fed-batch fermentation lactic acid productivity of 1.80 g L-1 h-1 has been achieved with a cell number of above 109 CFU mL-1. L. rhamnosus has shown high survival rate of over 85% in the presence of beef bile and at low pH value of MRS broth. The residuals after the fermentation were chemically analyzed and their composition corresponded well with the values recommended for the feed. The digestible energy was 17452.25 kJ kg-1, while metabolisable energy was 17360.83 kJ kg-1. The high values of energy parameters indicated that an integrated process for lactic acid and feedstuff production could be a good strategy. Mlečna kiselina je važna supstanca za prehrambenu industriju. Proizvodnja mlečne kiseline fermentacijom na otpadnim sirovinama može značajno da poveća ekonomičnost i održivost procesa. U ovom radu je ispitivana proizvodnja mlečne kiseline pomoću L. rhamnosus ATCC 7469 na džibri iz proizvodnje bioetanola na otpadnom hlebu. Pod optimalnim uslovima, u dolivnom postupku je postignuta produktivnost mlečne kiseline od 1.80 g L-1 h-1 sa više od 109 CFU mL-1 bakterija. L. rhamnosus je pokazao visok stepen preživljavanja od preko 85% u prisustvu žučnih soli i pri niskoj pH vrednosti MRS bujona. Ostatak nakon mlečno-kiselinske fermentacije džibre je hemijski analiziran i pokazano je da dobijene vrednosti odgovaraju preporučenim. Svarljiva energija je iznosila 17452,25 kJ kg-1, dok je metabolička energija bila 17360,83 kJ kg-1. Visoke vrednosti energetskih parametara hraniva ukazuju da integrisani proces proizvodnje mlečne kiseline i stočne hrane na džibri predstavlja povoljnu strategiju.

The production of lactic acid on a liquid distillery stillage remaining after the bioethanol production on a mixture of waste bread and waste water from the production of wheat gluten was studied in this work. The lactic acid fermentation was performed with a probiotic lactic acid bacteria Lactobacillus rhamnosus ATCC 7469. During the fermentation, parameters such as the concentration of lactic acid (according to Taylor method), the concentration of reducing sugars (spectrophotometric method according to Miller), pH, and the bacterial growth (counting method on agar plates) were followed. The optimal conditions for the production of lactic acid such as: temperature, inoculum concentration, concentration of added CaCO3 for neutralization and shaking intensity were determined. Under these conditions, a yield of over 80% of the theoretical yield was achieved. The highest intensity of the lactic acid production was noticed during the first 24 hours of fermentation, while the fermentation completely ended after 72 hours. An intensive growth of the L. rhamnosus ATCC 7469 was detected under the optimal conditions, indicating a possibility of the parallel production of lactic acid and probiotic biomass. This approach could be economically more favorable. The liquid stillage used in this study was shown as a good substrate for lactic acid fermentation. U radu je ispitivana proizvodnja mlečne kiseline na tečnoj destilerijskoj džibri nastaloj nakon proizvodnje bioetanola iz smeše otpadnog hleba i otpadne vode iz proizvodnje glutena. Mlečno-kiselinska fermentacija je vršena pomoću probiotički aktivne bakterije Lactobacillus rhamnosus ATCC 7469. U toku fermentacije praćen je sadržaj mlečne kiseline (po metodi Taylor-a), sadržaj redukujućih šećera (spektrofotometrijski metodom po Miller-u), pH, kao i rast bakterije (brojanjem ćelija Koh-ovom metodom na agarnim pločama). Utvrđeni su optimalni uslovi za proizvodnju mlečne kiseline: temperatura, koncentracija inokuluma, koncentracija dodatog CaCO3 kao sredstva za neutralizaciju i intenzitet mešanja. Pri utvrđenim optimalnim uslovima ostvareni su prinosi od preko 80% od teorijskog prinosa mlečne kiseline u mikroaerofilnoj fermentaciji sa mešanjem. Najveći intezitet fermentacije ostvaren je u toku prvih 24 časa, a fermentacija je završena nakon 72 časa. Pri optimalnim uslovima mlečnokiselinske fermentacije uočen je intenzivan rast bakterije Lactobacillus rhamnosus ATCC 7469 što ukazuje na mogućnost paralelne proizvodnje mlečne kiseline i probiotičke biomase, čime bi se mogli postići bolji ekonomski efekti. Ispitivana džibra se pokazala kao pogodan medijum za mlečno kiselinsku fermentaciju.

Food waste and fashion pollution are two of the significant global environmental issues throughout the recent past. In this research, it was investigated the feasibility of making a leather-like material from bread waste using biotechnology as the bridging mechanism. The waste bread collected from the supermarkets were used as the substrate to grow filamentous fungi species Rhizopus Delemar and Fusarium Venenatum. Tanning of fungal protein fibres was successfully performed using vegetable tanning, confirmed using FTIR and SEM images. Furthermore, glycerol and a biobased binder treatment was performed for the wet-laid fungal microfibre sheets produced. Overall, three potential materials were able to produce with tensile strengths ranging from 7.74 ± 0.55 MPa to 6.92 ± 0.51 MPa and the elongation% from 16.81 ± 1.61 to 4.82 ± 0.36. The binder treatment enhanced the hydrophobicity even after the glycerol treatment, an added functional advantage for retaining flexibility even after contact with moisture. The fungal functional material produced with bread waste can be tailored successfully into leather substitutes using an environmentally benign procedure.