Microstructure of high-pressure vs. atmospheric frozen starch gels

Martina Lille, Karin Autio

Research output: Contribution to journalArticleScientificpeer-review

4 Citations (Scopus)

Abstract

The aim of this study was to find out whether the ice crystal size of a starch gel, a model food system, could be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The size and number of pores in thawed gels was determined by light microscopy and image analysis, and was taken as an indirect measure of ice crystals formed during the different freezing processes studied. The pore size and the total area occupied by the pores were clearly reduced by high-pressure freezing at 150-240 MPa compared with freezing at atmospheric pressure at the same cooling rate. The pore size in the high-pressure (nor in the atmospheric) frozen gels did not increase during a storage time of 3 months at -24 °C (still air) at atmospheric pressure. Industrial relevance High-pressure processing at subzero temperatures is not yet industrially applied. More evidence on the benefits of high-pressure freezing or thawing on the quality of real food materials as well as development of processing equipment is needed for commercialization of the processes. This study demonstrates that the pore size of frozen and thawed starch gels can be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The reduced pore size was assumed to be a result of smaller ice crystals formed in the high-pressure freezing process. Based on this study, no conclusions can be drawn on the possibility of high-pressure freezing to improve the quality of real foods of a more complex composition and structure.
Original languageEnglish
Pages (from-to)117-126
JournalInnovative Food Science and Emerging Technologies
Volume8
Issue number1
DOIs
Publication statusPublished - 2007
MoE publication typeA1 Journal article-refereed

Fingerprint

starch gels
Starch
Freezing
microstructure
freezing
Gels
Pressure
Microstructure
Atmospheric Pressure
atmospheric pressure
Atmospheric pressure
Pore size
Ice
crystals
Food Quality
ice
Crystals
gels
model food systems
processing equipment

Keywords

  • High-pressure
  • Freezing
  • Starch gel
  • Microscopy
  • Texture

Cite this

@article{c846ddd8c527492aad89cab921639df6,
title = "Microstructure of high-pressure vs. atmospheric frozen starch gels",
abstract = "The aim of this study was to find out whether the ice crystal size of a starch gel, a model food system, could be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The size and number of pores in thawed gels was determined by light microscopy and image analysis, and was taken as an indirect measure of ice crystals formed during the different freezing processes studied. The pore size and the total area occupied by the pores were clearly reduced by high-pressure freezing at 150-240 MPa compared with freezing at atmospheric pressure at the same cooling rate. The pore size in the high-pressure (nor in the atmospheric) frozen gels did not increase during a storage time of 3 months at -24 °C (still air) at atmospheric pressure. Industrial relevance High-pressure processing at subzero temperatures is not yet industrially applied. More evidence on the benefits of high-pressure freezing or thawing on the quality of real food materials as well as development of processing equipment is needed for commercialization of the processes. This study demonstrates that the pore size of frozen and thawed starch gels can be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The reduced pore size was assumed to be a result of smaller ice crystals formed in the high-pressure freezing process. Based on this study, no conclusions can be drawn on the possibility of high-pressure freezing to improve the quality of real foods of a more complex composition and structure.",
keywords = "High-pressure, Freezing, Starch gel, Microscopy, Texture",
author = "Martina Lille and Karin Autio",
note = "HUO: NT Food Solutions CA2: TK405",
year = "2007",
doi = "10.1016/j.ifset.2006.08.002",
language = "English",
volume = "8",
pages = "117--126",
journal = "Innovative Food Science and Emerging Technologies",
issn = "1466-8564",
publisher = "Elsevier",
number = "1",

}

Microstructure of high-pressure vs. atmospheric frozen starch gels. / Lille, Martina; Autio, Karin.

In: Innovative Food Science and Emerging Technologies, Vol. 8, No. 1, 2007, p. 117-126.

Research output: Contribution to journalArticleScientificpeer-review

TY - JOUR

T1 - Microstructure of high-pressure vs. atmospheric frozen starch gels

AU - Lille, Martina

AU - Autio, Karin

N1 - HUO: NT Food Solutions CA2: TK405

PY - 2007

Y1 - 2007

N2 - The aim of this study was to find out whether the ice crystal size of a starch gel, a model food system, could be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The size and number of pores in thawed gels was determined by light microscopy and image analysis, and was taken as an indirect measure of ice crystals formed during the different freezing processes studied. The pore size and the total area occupied by the pores were clearly reduced by high-pressure freezing at 150-240 MPa compared with freezing at atmospheric pressure at the same cooling rate. The pore size in the high-pressure (nor in the atmospheric) frozen gels did not increase during a storage time of 3 months at -24 °C (still air) at atmospheric pressure. Industrial relevance High-pressure processing at subzero temperatures is not yet industrially applied. More evidence on the benefits of high-pressure freezing or thawing on the quality of real food materials as well as development of processing equipment is needed for commercialization of the processes. This study demonstrates that the pore size of frozen and thawed starch gels can be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The reduced pore size was assumed to be a result of smaller ice crystals formed in the high-pressure freezing process. Based on this study, no conclusions can be drawn on the possibility of high-pressure freezing to improve the quality of real foods of a more complex composition and structure.

AB - The aim of this study was to find out whether the ice crystal size of a starch gel, a model food system, could be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The size and number of pores in thawed gels was determined by light microscopy and image analysis, and was taken as an indirect measure of ice crystals formed during the different freezing processes studied. The pore size and the total area occupied by the pores were clearly reduced by high-pressure freezing at 150-240 MPa compared with freezing at atmospheric pressure at the same cooling rate. The pore size in the high-pressure (nor in the atmospheric) frozen gels did not increase during a storage time of 3 months at -24 °C (still air) at atmospheric pressure. Industrial relevance High-pressure processing at subzero temperatures is not yet industrially applied. More evidence on the benefits of high-pressure freezing or thawing on the quality of real food materials as well as development of processing equipment is needed for commercialization of the processes. This study demonstrates that the pore size of frozen and thawed starch gels can be reduced by high-pressure freezing compared with freezing at atmospheric pressure. The reduced pore size was assumed to be a result of smaller ice crystals formed in the high-pressure freezing process. Based on this study, no conclusions can be drawn on the possibility of high-pressure freezing to improve the quality of real foods of a more complex composition and structure.

KW - High-pressure

KW - Freezing

KW - Starch gel

KW - Microscopy

KW - Texture

U2 - 10.1016/j.ifset.2006.08.002

DO - 10.1016/j.ifset.2006.08.002

M3 - Article

VL - 8

SP - 117

EP - 126

JO - Innovative Food Science and Emerging Technologies

JF - Innovative Food Science and Emerging Technologies

SN - 1466-8564

IS - 1

ER -