dc.contributor.advisor |
Roos, Yrjö H. |
en |
dc.contributor.advisor |
Miao, Song |
en |
dc.contributor.author |
Li, Runjing |
|
dc.date.accessioned |
2017-05-03T12:16:39Z |
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dc.date.issued |
2017 |
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dc.date.submitted |
2017 |
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dc.identifier.citation |
Li, R. 2017. Studies on physical, mechanical, and industrially relevant properties of spray-dried dairy systems. PhD Thesis, University College Cork. |
en |
dc.identifier.endpage |
207 |
en |
dc.identifier.uri |
http://hdl.handle.net/10468/3912 |
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dc.description.abstract |
Engineering properties of food solids are highly dependent on their physical state, i.e. amorphous, crystalline, or liquid. Understanding glass transition-related relaxations and their coupling with engineering properties of food materials is highly essential. The present study investigated the physical and mechanical properties of two model dairy solids systems: (i) lactose/milk protein isolate (MPI) solids systems produced by a laboratory scale spray dryer and a pilot scale spray dryer, respectively; (ii) lactose/whey protein isolate (WPI) (4:1) mixtures pre-crystallised before spray drying. Dairy solids with smaller size particles showed lower glass transition temperatures (Tg) after equilibration at 0.11-0.33 aw. For lactose/WPI (4:1) mixtures with different crystallinity, increasing the amount of crystalline lactose had no significant influence on the glass transition temperatures and the initial crystallization temperatures at 0.11-0.44 aw. The present study also investigated the flow properties of two dairy-based solids systems: (i) lactose/MPI solids systems; (ii) lactose/WPI solids systems pre-crystallized before spray drying. Lactose/MPI mixtures with higher lactose contents showed better flowability at 0 and 44% relative humidity (RH). For pre-crystallization systems, flow function tests indicated that dairy solid with 11.2% crystallinity was more easy-flowing than lactose/WPI mixtures with 1.0, 29.2 and 46.8% crystallintiy. At last, the effect of formulation on encapsulation properties and flavor release of amorphous matrix was studied. Firstly, lactose/WPI (4:1, 1:1, and 1:4) mixtures, or WPI were used as wall systems. Wall material consisting of lactose/WPI (4:1) mixture had significantly (P < 0.05) higher encapsulation efficiency. Then, the encapsulation properties of dairy solids using lactose/WPI (4:1) or lactose/maltodextrin (MD)/WPI (3:1:1 or 1:3:1) mixtures as wall systems were determined. Wall systems consisting with lactose/MD (13-17)/WPI (1:3:1) mixtures and lactose/MD (23-27)/WPI mixtures had higher flavor retention than other wall systems after equilibration at high water activity (≥ 0.54 aw). |
en |
dc.description.sponsorship |
Department of Agriculture, Food and the Marine (FIRM Grant 11-F-001) |
en |
dc.format.mimetype |
application/pdf |
en |
dc.language.iso |
en |
en |
dc.publisher |
University College Cork |
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dc.rights |
© 2017, Runjing Li. |
en |
dc.rights.uri |
http://creativecommons.org/licenses/by-nc-nd/3.0/ |
en |
dc.subject |
Dairy powders |
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dc.subject |
Glass transition |
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dc.subject |
Mechanical properties |
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dc.subject |
Flow properties |
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dc.subject |
Encapsulation properties |
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dc.title |
Studies on physical, mechanical, and industrially relevant properties of spray-dried dairy systems |
en |
dc.type |
Doctoral thesis |
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dc.type.qualificationlevel |
Doctoral |
en |
dc.type.qualificationname |
PhD (Food Science and Technology) |
en |
dc.internal.availability |
Full text not available |
en |
dc.check.info |
Restricted to everyone for one year |
en |
dc.check.date |
2018-05-03T12:16:39Z |
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dc.description.version |
Accepted Version |
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dc.contributor.funder |
Department of Agriculture, Food and the Marine
|
en |
dc.description.status |
Not peer reviewed |
en |
dc.internal.school |
Food and Nutritional Sciences |
en |
dc.internal.school |
Teagasc |
en |
dc.check.reason |
This thesis is due for publication or the author is actively seeking to publish this material |
en |
dc.check.opt-out |
Not applicable |
en |
dc.thesis.opt-out |
false |
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dc.check.entireThesis |
Entire Thesis Restricted |
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dc.check.embargoformat |
E-thesis on CORA only |
en |
ucc.workflow.supervisor |
yrjo.roos@ucc.ie |
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dc.internal.conferring |
Summer 2017 |
en |