Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment.However,these wastewater streams are rich in minerals,fat,and...Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment.However,these wastewater streams are rich in minerals,fat,and proteins that can be converted to protein-rich feed ingredients through submerged cultivation of edible filamentous fungi.In this study,the origin of wastewater stream,initial pH,cultivation time,and extent of washing during sieving,were found to influence the amount of recovered material from the wastewater streams and its protein content,following cultivation with Aspergillus oryzae.Through culti-vation of the filamentous fungus in sludge,330 kg of material per ton of COD were recovered by sieving,corresponding to 121 kg protein per ton of COD,while through its cultivation in salt brine,210 kg of material were recovered per ton of COD,corresponding to 128 kg protein per ton of COD.Removal ranges of 12-43%,39-92%,and 32-66%for COD,total solids,and nitrogen,respectively,were obtained after A.oryzae growth and harvesting in the wastewater streams.Therefore,the present study shows the versatility that the integration of fungal cultivation provides to fish processing industries,and should be complemented by economic,environmental,and feeding studies,in order to reveal the most promising valorization strategy.展开更多
Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(deca...Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(decanting/sieving or centrifugation),reagents(sodium bicarbonate or sodium hydroxide)and washing cycles(1–4)on the quality of protein concentrates obtained from mechanically separated meat(MSM)and viscera of hybrid sorubim(Pseudoplatystoma reticulatum×P.corruscans)and pacu(Piaractus mesopotamicus)fishes.The protein concentrate was obtained by washing the viscera or MSM during up to four cycles(4:1 solution:meat ratio).In each cycle,the liquid waste and fat were removed by decanting/sieving or centrifugation.Moisture,crude protein,crude fat and crude ash contents were determined after each washing cycle.The moisture and protein contents increased immediately after the first washing up to 77.88%(dry basis).The lipid content decreased with the cycles down to 2.99%(dry basis).Higher FPC yield was obtained for MSM during the centrifugation process compared to the decantation/sieving process.Two weight yields above 100%were found in procedures with NaHCO3 and MSM of hybrid sorubim and pacu,probably due to the larger capacity of gel formation during protein concentration.Differences related to the fish species were more evident than the processes and utilized reagents.展开更多
基金This work was supported by the Swedish Agency for Economic and Regional Growth(Tillväxtverket)through a European Regional Development Fund.
文摘Fish processing towards production of fillet gives rise to wastewater streams that are ultimately directed to biogas production and/or wastewater treatment.However,these wastewater streams are rich in minerals,fat,and proteins that can be converted to protein-rich feed ingredients through submerged cultivation of edible filamentous fungi.In this study,the origin of wastewater stream,initial pH,cultivation time,and extent of washing during sieving,were found to influence the amount of recovered material from the wastewater streams and its protein content,following cultivation with Aspergillus oryzae.Through culti-vation of the filamentous fungus in sludge,330 kg of material per ton of COD were recovered by sieving,corresponding to 121 kg protein per ton of COD,while through its cultivation in salt brine,210 kg of material were recovered per ton of COD,corresponding to 128 kg protein per ton of COD.Removal ranges of 12-43%,39-92%,and 32-66%for COD,total solids,and nitrogen,respectively,were obtained after A.oryzae growth and harvesting in the wastewater streams.Therefore,the present study shows the versatility that the integration of fungal cultivation provides to fish processing industries,and should be complemented by economic,environmental,and feeding studies,in order to reveal the most promising valorization strategy.
文摘Fish protein concentration(FPC)by alkaline solubilization has proven to be an alternative method in adding value to muscle-based materials.The aim of this work was to evaluate the influence of different processes(decanting/sieving or centrifugation),reagents(sodium bicarbonate or sodium hydroxide)and washing cycles(1–4)on the quality of protein concentrates obtained from mechanically separated meat(MSM)and viscera of hybrid sorubim(Pseudoplatystoma reticulatum×P.corruscans)and pacu(Piaractus mesopotamicus)fishes.The protein concentrate was obtained by washing the viscera or MSM during up to four cycles(4:1 solution:meat ratio).In each cycle,the liquid waste and fat were removed by decanting/sieving or centrifugation.Moisture,crude protein,crude fat and crude ash contents were determined after each washing cycle.The moisture and protein contents increased immediately after the first washing up to 77.88%(dry basis).The lipid content decreased with the cycles down to 2.99%(dry basis).Higher FPC yield was obtained for MSM during the centrifugation process compared to the decantation/sieving process.Two weight yields above 100%were found in procedures with NaHCO3 and MSM of hybrid sorubim and pacu,probably due to the larger capacity of gel formation during protein concentration.Differences related to the fish species were more evident than the processes and utilized reagents.
