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Extraction and downstream processing of black soldier fly larvae protein
Thesis (MEng)--Stellenbosch University, 2023.
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Stellenbosch : Stellenbosch University
2023
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| access_status_str | Open Access |
| author | Chakawa, Dennis Panashe |
| author2 | Goosen, Neill Jurgens |
| author_browse | Chakawa, Dennis Panashe Goosen, Neill Jurgens |
| author_facet | Goosen, Neill Jurgens Chakawa, Dennis Panashe |
| author_sort | Chakawa, Dennis Panashe |
| collection | Thesis |
| dc_rights_str_mv | Stellenbosch University |
| description | Thesis (MEng)--Stellenbosch University, 2023. |
| format | Thesis |
| id | oai:scholar.sun.ac.za:10019.1/129041 |
| institution | Stellenbosch University (South Africa) |
| language | en_ZA en_ZA |
| last_indexed | 2026-06-10T12:43:32.400Z |
| license_str | Other — see source repository |
| provenance_str_mv | Harvested via OAI-PMH from SUNScholar — Stellenbosch University Repository |
| publishDate | 2023 |
| publishDateRange | 2023 |
| publishDateSort | 2023 |
| publisher | Stellenbosch : Stellenbosch University |
| publisherStr | Stellenbosch : Stellenbosch University |
| record_format | dspace |
| source_str | SUNScholar — Stellenbosch University Repository |
| spelling | oai:scholar.sun.ac.za:10019.1/129041 Extraction and downstream processing of black soldier fly larvae protein Chakawa, Dennis Panashe Goosen, Neill Jurgens Stellenbosch University. Faculty of Engineering. Dept. of Chemical Engineering. Process Engineering. Edible insects Amino acids in nutrition Hydrolases Alkaline extraction Ultrafiltration Thesis (MEng)--Stellenbosch University, 2023. ENGLISH ABSTRACT: It has become imperative for new sustainable protein sources to be sought, coupled with the development of effective processing technology. According to the United Nations, the global population is estimated to increase to more than 11 billion people by 2100 that will increase the demand for protein products by 75% and alternative protein sources will be required to supply a proportion of the increase. There exists a shortage of agricultural land to increase the production of conventional animal and plant proteins. Amongst the sustainable sources of protein, black soldier fly larvae (BSFL) are promising because they have high production rates, low water requirements and greenhouse emissions, and contain significant levels of protein. However, there is an aversion by Western consumers to the consumption of whole insects. Customer acceptance can be improved if insect protein is extracted and converted into a powder form for human consumption. There is scarce literature on a process to produce BSFL protein powder from BSFL. The study aimed to develop a process to produce BSFL protein powder and was achieved using two objectives. The first objective was to investigate optimum extraction conditions for enzymatic hydrolysis at pH 7-9 and pH 10-12, determine whether two-stage extraction would significantly improve overall protein recovery compared to a single stage, and determine the proximate composition of the powder produced after spray drying the aqueous extract. Aqueous extraction using enzymatic hydrolysis was selected because it allows for the selective removal of protein into the aqueous phase separating it from lipids and insoluble chitin. Protein recovery using enzymatic hydrolysis was done using Alcalase 2.4 L. Enzymatic hydrolysis at the pH 10-12 achieved the highest protein recovery of 68% for single stage extraction, at optimum conditions (temperature, pH, E/S, and time of 85 ℃, 11, and 150 min, respectively). Conversely, enzymatic hydrolysis at pH 7-9 achieved a protein recovery of 67.2% for single stage extraction at optimum conditions (temperature, pH, E/S, and time of 55 ℃, 9, 1%, and 180 min, respectively). From these results it was evident that enzyme addition at pH 10-12 had an insignificant effect on protein recovery therefore making the extraction predominantly alkaline extraction. To investigate the two-stage extraction sequence, alkaline extraction followed by alkaline extraction (two stage alkaline extraction sequence) was compared with alkaline extraction followed by enzymatic hydrolysis (alkaline extraction-enzymatic hydrolysis extraction sequence). Two-stage alkaline extraction sequence at optimum conditions achieved a higher cumulative recovery of 83.8% compared to the alkaline extraction-enzymatic hydrolysis extraction sequence which achieved a protein recovery of 71.1%. The aqueous extract from two-stage alkaline extraction was spray dried at an air flowrate, feed flowrate and air Stellenbosch University https://scholar.sun.ac.za iv inlet temperature of 64.1 m3 /h, 0.06 L/hr, and 180 ℃ respectively and produced a brown powder with a protein, ash, and moisture content of 45.1%, 53.5%, and 1.4%, respectively. The high ash content as compared to that of protein in the powder was attributed to excessive ash content that was added to the aqueous extract during neutralization of the aqueous extract from a pH of 10-12 to 9 before spray drying. These results demonstrate that that a two-stage alkaline extraction at optimum conditions is a suitable protein recovery sequence capable of recovering protein from BSFL. However, it introduces significant quantities of ash in the aqueous mixture during pH neutralization which produces a BSFL powder with a low protein content and high ash content when spray dried. The second objective was to investigate the best technology and filtration conditions for deashing the BSFL aqueous extract using batch ultrafiltration and continuous diafiltration, and then determine the nutritional composition of the powder obtained after spray drying the deashed aqueous extract. This was done using a 10 kDa polyethersulfone (PES) membrane. After filtration, the deashed retentate was mixed with 30% (w/w) maltodextrin, concentrated to 30% total solids, and spray dried at a temperature, air flowrate, and feed flowrate of 180 °C, 64.1 m3 .h-1, and 0.06 L.h-1 , respectively. Filtration conditions for batch ultrafiltration and continuous diafiltration obtained were at a temperature, transmembrane pressure (TMP), and cross flowrate of 30 °C, 3.1 bar, and 383 ml/min, respectively. Batch ultrafiltration lasted for 60 min and resulted in a decrease in permeate flux from 8.67 to 4.4 L.m-2 .h-1 and an increase in volume concentration factor (VCF) from 1 to 1.56. This produced a retentate with a protein, ash, and total solids content of 48.9, 51.1, and 18.4 (%) (w/w), respectively. On the contrary, continuous diafiltration at similar conditions using three diavolumes of water for 890 min produced a retentate with protein and ash contents of 96.4 and 3.6% (w/w), respectively. This was achieved as permeate flux decreased from 5.5 to 4.76 L.m2 .h-1 . The powder yield after spray drying was 61% with protein, ash, and moisture content of the powder is 52.1, 3, and 0.05%, respectively. These results show that continuous diafiltration is more effective at deashing BSFL aqueous extracts than batch ultrafiltration making it suitable for deashing the aqueous extract after protein extraction. In conclusion, a BSFL process consisting of a two-stage alkaline extraction sequence, batch diafiltration to deash aqueous extract, and spray drying of the diafiltered extract can produced a protein powder from BSFL. Therefore, the aim of the study was achieved. AFRIKAANSE OPSOMMING: Dit het noodsaaklik geword om vir nuwe volhoubare proteïenbronne te soek, gepaard met die ontwikkeling van effektiewe prosesseringstegnologie. Volgens die Verenigde Nasies, sal die globale populasie in 2100 na meer as 11 biljoen mense verhoog wat die aanvraag vir proteïenprodukte met 75% sal laat styg en alternatiewe proteïenbronne sal vereis word om ’n deel van hierdie toename te verskaf. Daar bestaan ’n tekort aan landbougrond om die produksie van konvensionele dier- en plantproteïene te verhoog. Onder die volhoubare bronne van proteïene, is venstervlieglarwe (BSFL) belowend omdat hulle hoë produksiewaardes, lae watervereistes en groenhuisemissies het, en bevat beduidende vlakke van proteïene. Daar is egter ’n afkerigheid by Westerse verbruikers vir die gebruik van heel insekte. Verbruikeraanvaarding kan verbeter word as insekproteïen geëkstraheer en omgesit word in ’n poeiervorm vir menslike gebruik. Literatuur rakend ’n proses om BSFL-proteïenpoeier vanuit BSFL te vervaardig, is skaars. Die studie beoog om ’n proses te ontwikkel om BSFL-proteïenpoeier te produseer, en is bereik deur twee doelwitte te gebruik. Die eerste doelwit was om optimum ekstraheringkondisies vir ensimatiese hidrolise by by pH 7 – 9 en pH 10 – 12 te ondersoek, te bepaal of tweefase ekstrahering die algehele proteïenherwinning beduidend sal verbeter in vergelyking met ’n enkelfase, en om die proksimale komposisie van die poeier geproduseer na spuitdroging van die waterige ekstraksie te bepaal. Waterige ekstraksie wat ensimatiese hidrolise gebruik, is gekies omdat dit die selektiewe verwydering van proteïen in die waterige fase toelaat, wat dit van lipiede en onoplosbare chitien skei. Proteïenherwinning deur ensimatiese hidrolise is gedoen deur Alcalase 2.4 L te gebruik. Ensimatiese hidrolise by pH 10 - 12 het die hoogste proteïenherwinning van 68% vir enkelfase ekstraksie bereik by optimum kondisies (temperatuur, pH, E/S, en tyd van 85 °C, 11, en 150 min, onderskeidelik). Daarteenoor het ensimatiese hidrolise by pH 7 - 9 ’n proteïenherwinning van 67.2% vir enkelfase-ekstraksie by optimum kondisies bereik (temperatuur, pH, E/S, en tyd van 55 °C, 9, 1%, en 180 min, onderskeidelik). Vanuit hierdie resultate was dit duidelik dat ensiem-byvoeging by pH 10 - 12 ’n onbeduidende effek op proteïenherwinning gehad het, en daarom is die ekstraksie oorwegend alkaliese ekstraksie. Om die tweefase-ekstrasiereeks te ondersoek, is alkaliese ekstraksie gevolg deur alkaliese ekstrasie (tweefase alkaliese ekstraksiereeks) vergelyk met ’n alkaliese ekstraksie gevolg deur ensimatiese hidrolise (alkaliese ekstraksie-ensimatiese hidrolise ekstraksiereeks). Tweefase alkaliese ekstraksie-ekstraksiereeks by optimum kondisies het ’n hoër kumulatiewe herwinning van 83.8% bereik in vergelyking met die alkaliese ekstraksie-ensimatiese hidrolise ekstraksiereeks wat ’n proteïenherwinning van 71.1% bereik het. Stellenbosch University https://scholar.sun.ac.za vi Die waterige ekstrak van tweefase alkaliese ekstraksie is gespuitdroog by ’n lugvloeitempo, voervloeitempo en luginlaattemperatuur van 64.1 m3 /h, 0.06 L/hr, en 180 °C onderskeidelik, en het ’n bruin poeier met ’n proteïen, as, en voginhoud van 45.1%, 53.5%, en 1.4% onderskeidelik geproduseer. Die hoë asinhoud, soos vergelyk met dié van proteïen in die poeier, is toegeskryf aan oormatige asinhoud wat bygevoeg is by die waterige ekstrak gedurende neutralisasie van die waterige ekstrak van ’n pH van 10 tot 12 na 9 voor spuitdroging. Hierdie resultate demonstreer dat ’n tweefase alkaliese ekstraksie by optimum kondisies ’n gepaste proteïenherwinningsreeks is, in staat om proteïen van BSFL te herwin. Dit bring egter beduidende hoeveelhede as in die waterige mengsel gedurende pH-neutralisasie wat ’n BSFL-poeier met lae proteïeninhoud en hoë asinhoud produseer wanneer dit gespuitdroog word. Die tweede doelwit was om die beste tegnologie en filtrasiekondisies vir asverwydering van die BSFLwaterige ekstrak te ondersoek deur lot-ultrafiltrasie en aaneenlopende diafiltrasie te gebruik, en dan die nutriëntkomposisie van die poeier te bepaal nadat die asverwyderde waterige ekstrak gespuitdroog is. Dit is gedoen deur ’n 10 kDa poliëtersulfoonmembraan (PES) te gebruik. Na filtrasie, is die asverwyderde retentaat gemeng met 30% (w/w) maltodekstrien, gekondenseer na 30% totale vaste stowwe, en gespuitdroog by ’n temperatuur, lugvloeitempo en voervloeitempo van 180 °C, 64.1 m3 .h-1 , en 0.06 L.h-1 , onderskeidelik. Filtrasiekondisies vir lot-ultrafiltrasie en aaneenlopende diafiltrasie is verkry by ’n temperatuur, transmembraandruk (TMP), en kruisvloeitempo van 30 °C, 3.1 bar, en 383 ml/min, onderskeidelik. Lot-ultrafiltrasie het vir 60 min aangehou en het ’n verlaagde deurlaatfluks van 8.67 tot 4.4 L.m-2 .h-1 en ’n verhoging in volumekonsentrasiefaktor (VCF) van 1 tot 1.56 tot gevolg gehad. Hierdie het ’n retentaat met ’n proteïen-, as-, en totale vaste stowwe-inhoud van 48.9, 51.1, en 18.4 (%) (w/w) onderskeidelik, gehad. Daarenteen, het aaneenlopende diafiltrasie by soortgelyke kondisies wat drie diavolumes water vir 890 min gebruik het, ’n retentaat met proteïen- en asinhoude van 96.4 en 3.6% (w/w), onderskeidelik, geproduseer. Dit is bereik soos deurlaatfluks verlaag het van 5.5 tot 4.76 L.m-2 .h-1 . Die poeieropbrengs na sproeidroging was 61% met proteïen-, as-, en voginhoud van die poeier 52.1, 3, en 0.05%, onderskeidelik. Hierdie resultate wys dat aaneenlopende diafiltrasie meer effektief is met asverwydering in BSFL-waterige ekstrakte as lot-ultrafiltrasie, wat dit meer gepas maak vir asverwydering van die waterige ekstrak na proteïenekstraksie. Ter slotte, ’n BSFL-proses wat bestaan uit ’n tweefase alkaliese ekstraksiereeks, lotdiafiltrasie om as uit waterige ekstrak te verwyder, en spuitdroging van die diagefiltreerde ekstrak, kan ’n proteïenpoeier van BSFL produseer. Daarom is die doel van hierdie studie bereik. Masters 2023-11-29T08:06:27Z 2024-01-08T20:15:32Z 2023-11-29T08:06:27Z 2024-01-08T20:15:32Z 2023-12 Thesis https://scholar.sun.ac.za/handle/10019.1/129041 en_ZA en_ZA Stellenbosch University xix, 137 pages : illustrations application/pdf Stellenbosch : Stellenbosch University |
| spellingShingle | Edible insects Amino acids in nutrition Hydrolases Alkaline extraction Ultrafiltration Chakawa, Dennis Panashe Extraction and downstream processing of black soldier fly larvae protein |
| title | Extraction and downstream processing of black soldier fly larvae protein |
| title_full | Extraction and downstream processing of black soldier fly larvae protein |
| title_fullStr | Extraction and downstream processing of black soldier fly larvae protein |
| title_full_unstemmed | Extraction and downstream processing of black soldier fly larvae protein |
| title_short | Extraction and downstream processing of black soldier fly larvae protein |
| title_sort | extraction and downstream processing of black soldier fly larvae protein |
| topic | Edible insects Amino acids in nutrition Hydrolases Alkaline extraction Ultrafiltration |
| url | https://scholar.sun.ac.za/handle/10019.1/129041 |
| work_keys_str_mv | AT chakawadennispanashe extractionanddownstreamprocessingofblacksoldierflylarvaeprotein |