Inkapsulacija sirila u formulacije alginatnih mikročestica

master's thesis

• Title (english): Encapsulation of rennet in natrium sodium microspheres
• Author: Ana-Marija Aničić
• Mentor: Marko Vinceković (mentor)
• Committee member: Marko Vinceković (predsjednik povjerenstva)
• Committee member: Nataša Mikulec (član povjerenstva)
• Committee member: Luna Maslov Bandić (član povjerenstva)
• Granter: University of Zagreb; Faculty of Agriculture; (Chemistry); Zagreb
• Defense date and country: 2023-09-22, Croatia
• Scientific / art field, discipline and subdiscipline: BIOTECHNICAL SCIENCES; Agronomy

Abstract

Sirilo je pripravak enzima životinjskog, biljnog ili mikrobnog porijekla koji se koristi u proizvodnji sira za koagulaciju mlijeka. Prirodno sirilo životinjskog porijekla se koristi već stoljećima, no povećane potrebe za sirilom u prošlom stoljeću potaknule su razvoj i korištenje sirila mikrobnog i GMO modificiranog porijekla. Prirodno sirilo dobiva se iz sirišta mlade sisajuće teladi, janjadi i jaradi. U posljednje vrijeme stabilizacija sirila, posebno kod ubrzanog zrenja sira, izaziva značajan interes. Kako bi se povećala dugotrajnija aktivnost i stabilnost sirila provodi se postupak inkapsulacije sirila u formulacije alginatnih mikročestica čime se postiže imobilizacija i otpuštanje enzima u određenim vremenskim intervalima. U radu je provedena optimizacija koncentracije natrijevog alginata i kalcijevog klorida na inkapsulaciju sirila. U optimalnim uvjetima alginat je bio 1,5%, a CaCl2 4%. U optimalnim uvjetima, učinkovitost inkapsulacije (EE%), kapacitet ispune (LC), veličina mikročestice i stupanj bubrenja (Sw) procijenjeni su na 56,8%, 80%, 1386,51 ± 0,231 mm odnosno 61,8%. Također, podaci o otpuštanju sirila (enzima) prilagođeni su Korsmeyer-Peppasovom modelu, a eksponent n > 0,43 upućuje da je kontrolni mehanizam otpuštanja anomalna transportna kinetika (kombinacija dvaju difuzijskih mehanizama i bubrenja i relaksacije polimernih lanaca). Elektrostatske interakcije između enzima, alginata i CaCl2 potvrđene su infracrvenom spektroskopijom, a morfologija mikročestica je određena pomoću optičkog mikroskopa (OM) i pretražnog elektronskog mikroskopa (SEM).

Abstract (english)

Rennet is a form of enzyme preparation of animal, plant or microbial origin that is used in cheese production to induce milk coagulation. The natural rennet of animal origin was used for centuries until high demand resulted in development and use of microbial and GMO modified rennets in the last century. Natural rennet is produced from abomasum of young suckling calves, lambs, and goats. To increase the stability and long-term activity of the rennet, the process of encapsulating the rennet in alginate microparticle formulations is carried out, which achieves the immobilization and release of enzymes at certain time intervals. Even recently, the stabilization of rennet, especially in the case of accelerated cheese ripening, has been attracting considerable interest. In this work, the optimization of the concentration of sodium alginate and calcium chloride for the encapsulation of rennet was carried out. Under optimal conditions, alginate was 1.5% and CaCl2 was 4%. Under optimal conditions, encapsulation efficiency (EE%), filling capacity (LC), microparticle size, and degree of swelling (Sw) were estimated to be 56.8%, 80%, 1386.51 ± 0.231 mm, and 61.8%, respectively. In addition, the data on rennet (enzyme) release were adapted to the Korsmeyer-Peppas model, and the exponent n > 0.43 indicates that the controlling mechanism of the release is anomalous transport kinetics (combination of two diffusion mechanisms and swelling and relaxation of polymer chains). Electrostatic interactions between the enzyme, alginate, and CaCl2 were confirmed by infrared spectroscopy, and the morphology of the microparticle was determined using an optical microscope (OM) and a scanning electron microscope (SEM).

• Keywords: inkapsulacija; sirilo; mikrosfere; sirište; alginat
• Keywords (english): encapsulation; rennet; microparticles; abomasum; alginate
• Language: croatian
• URN:NBN: urn:nbn:hr:204:695695
• Study programme: Title: Production and Processing of Milk; Study programme type: university; Study level: graduate; Academic / professional title: magistar / magistra inženjer/inženjerka proizvodnje i prerade mlijeka (magistar / magistra inženjer/inženjerka proizvodnje i prerade mlijeka)
• Type of resource: Text
• File origin: Born digital
• Access conditions: Open access
• Created on: 2023-09-26 06:53:19