https://digital.csic.es/bitstream/10261/63157/4/Gomez-Guillen-collagenreview_CSIC.pdf

Functional and bioactive properties of collagen and gelatin from alternative sources: A review

https://uhra.herts.ac.uk/bitstream/handle/2299/15972/Microencapsulation_of_Probiotics_For_Gastrointestinal_Delivery_.pdf?sequence=2

Microencapsulation of probiotics for gastrointestinal delivery.

The terms gels and hydrogels are used interchangeably by food and biomaterials scientists to describe polymeric cross-linked network structures. Gels are defined as a substantially dilute cross-linked system, and are categorised principally as weak or strong depending on their flow behaviour in steady-state (Ferry, 1980). Edible gels are used widely in the food industry and mainly refer to gelling polysaccharides (i.e. hydrocolloids) (Phillips & Williams, 2000). The term hydrogel describes three-dimensional network structures obtained from a class of synthetic and/or natural polymers which can absorb and retain significant amount of water (Rosiak & Yoshii, 1999). The hydrogel structure is created by the hydrophilic groups or domains present in a polymeric network upon the hydration in an aqueous environment. This chapter reviews the preparation methods of hydrogels from hydrophilic polymers of synthetic and natural origin with emphasis on water soluble natural biopolymers (hydrocolloids). Recent advances in radiation cross-linking methods for the preparation of hydrogel are particularly addressed. Additionally, methods to characterise these hydrogels and their proposed applications are also reviewed.

/pdf/hydrogels-methods-of-preparation-characterisation-and-3g2ty7j722.pdf

Hydrogels: Methods of Preparation, Characterisation and Applications

Hydrogels as intelligent materials: A brief review of synthesis, properties and applications

A mini review on hydrogels classification and recent developments in miscellaneous applications.

Preparation of alginate/chitosan/carboxymethyl chitosan complex microcapsules and application in Lactobacillus casei ATCC 393

Preparation and characteristics of novel porous hydrogel films based on chitosan and glycerophosphate

Lactobacillus casei ATCC 393-loaded microcapsules based on alginate and gelatin had been prepared by extrusion method and the product could increase the cell numbers of L. casei ATCC 393 to be 10(7) CFU g(-1) in the dry state of microcapsules. The microparticles homogeneously distributed with size of 1.1 ± 0.2 mm. Four kinds of microcapsules (S(1), S(2), S(3) and S(4)) exhibited swelling in simulated gastric fluid (SGF) while the beads eroded and disintegrated rapidly in simulated intestinal fluid (SIF). Cells of L. casei ATCC 393 could be continuously released from the microcapsules during simulated gastrointestinal tract (GIT) and the release amounts and speeds in SIF were much higher and faster than that in SGF. Encapsulation in alginate-gelatin microcapsules successfully improved the survival of L. casei ATCC 393 and this approach might be useful in delivery of probiotic cultures as a functional food.

Microencapsulation of a probiotic bacteria with alginate-gelatin and its properties

Six kinds of Bifidobacterium bifidum microcapsules were prepared by extrusion methods, emulsion methods and coacervation methods. Effects of preparation methods on the survival of encapsulated B. bifidum were examined. Results showed that microcapsules prepared by emulsion method with alginate and chitosan exhibited the best protection for B. bifidum. The diameter was 10-20 µm, encapsulation efficiency was 90.36% and the live cell amount was 3.01 × 10₉ cfu/g after freeze-drying. Encapsulated cells exhibited significantly higher resistance to artificial gastrointestinal juice and the cell numbers were above 10₉ cfu/g after exposure to simulated gastric (pH 1.2) and bile salt (1%, w/v). Cell numbers of microencapsulated B. bifidum was 8.61 × 10₈ cfu/g after storage at 37°C, relative humidity 60%-65% for 3 months. Results indicated microcapsules prepared with alginate and chitosan by emulsion method could successfully protect B. bifidum against adverse conditions and it might be useful in the delivery of probiotic cultures as a functional food.

Effect of microencapsulation methods on the survival of freeze-dried Bifidobacterium bifidum.

Encapsulated Lactobacillus casei ATCC 393 was prepared by extrusion technology with rice shell powder and alginate followed by drying at 4°C. Drying at 4°C was beneficial to the survival of L. casei ATCC 393 compared with freeze drying. Trehalose had a positive effect on the survival of dried L. casei ATCC 393; the live cell numbers remained over 107 cfu/g after 8 weeks of storage at 4°C. Survival of L. casei ATCC 393 decreased with the increase of relative humidity (from 33 to 97%) while the immobilization technique protected cells from adverse gastric conditions (pH 1.2) by the survival ratio of 89%.

Xiao Yan Li

Papers

Preparation of alginate/chitosan/carboxymethyl chitosan complex microcapsules and application in Lactobacillus casei ATCC 393

Preparation and characteristics of novel porous hydrogel films based on chitosan and glycerophosphate

Microencapsulation of a probiotic bacteria with alginate-gelatin and its properties

Effect of microencapsulation methods on the survival of freeze-dried Bifidobacterium bifidum.

Effect of Trehalose and Drying Process on the Survival of Encapsulated Lactobacillus casei ATCC 393