ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00400.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTW/O/W‐type multiple emulsions have potential applications for the formulation and processing of foods, as each dispersed globule in this type of emulsion consists of single or multiple aqueous compartments separated from the aqueous suspending fluid by a layer of the oil phase components. Three different methods can be applied to prepare W/O/W emulsions, such as mechanical agitation, the phase inversion technique and a two‐stage emulsification. The oil layer in the W/O/W emulsions appears to thin immediately after the preparation, and water permeates through the narrow oil layer under the osmotic pressure gradient between the two aqueous phases. Therefore, it is believed that the thin oil layer may contain the hydrophobic emulsifier in a lamella structure. Addition of electrolytes to the aqueous phase causes instability of the W/O/W‐type dispersion due to rupture of the thin oil layer, or aggregation formation amongst the dispersed globules. A systematic study of the W/O/W emulsion stability is desirable in view of possible applications of this type of emulsion in

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00401.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe rheological properties of carrageenan/gelatin and agar/gelatin mixed gels were investigated by measuring the rupture properties, the texture parameters and the dynamic viscoelasticities. fie melting point, transparency and syneresis of these gels were measured in order to obtain the relationship with the rheological properties. The physical properties of the two mixed gels were slightly different. The agar/gelatin mixed gels generally showed the hindered effect of gelatin. The brittleness of agar gel disappeared on mixing with gelatin. It then became a flexible, cohesive and transparent gel. Carrageenan/gelatin mixed gels showed a decrease in the values of almost all of the mechanical properties when compared with carrageenan gels. However, the rupture properties of the C0.5 mixed gel were much higher than those of simple carrageenan gels.

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00402.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00403.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe mechanism of the formation of a rigid foam structure during whipping of reconstituted whipping cream was investigated. The rheological properties of whipped cream were estimated from an analysis of shear creep curves by a four element model. The values of each element increased exponentially during the process of whipping. From cryo‐SEM observation, the surface of air bubbles consisted of a thin membrane which was penetrated by fat globules. Also, fat globules in the serum were joined together by free fat to form a framework structure.The relationship between the rheological properties and microstructure of whipped cream was deduced from the rheological properties of two model systems. It is believed that whipped cream is a mixed matrix of a SOB O/W structure and a stiffer W/O structur

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00404.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

摘要:

ABSTRACTThe apparent viscosity of human milk, fresh cow's milk, homogenized milk, skim milk and oleic acid emulsion have been determined in a Maron‐Belner type low shear capillary viscometer using capillaries of different radii combined with a photomicroscope. Photomicrographs of the flowing fluids have been obtained and analyzed by a densitometer. Each suspension examined showed different apparent viscosities and the viscosities depended also on capillary radius. This capillary radius effect was traced to migration of milk fat droplets during flow through the capillary. By assuming that the wall layer is composed of double layers in a flowing liquid in a capillary tube this radius effect may be attributed to geometric hindrance of the capillary wall against the thermal motion of fat droplets near the wall, Values of the wall thickness were calculate

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00405.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY

ISSN:0022-4901    

DOI:10.1111/j.1745-4603.1986.tb00399.x

出版商:Blackwell Publishing Ltd    

年代:1986

数据来源: WILEY