| Summary: | 碩士 === 國立中興大學 === 畜牧學系 === 84 === The values of meat products are competitive in the market,
and low cost of products is the most important factor among
competitive factors. As to maintain the meat product cost
stably, meat productors usually used meat proteins or non-meat
proteins or other low cost raw materials to carry out this
target. Theadditives will influence the quality of the meat
products because of kinds, amounts and processing. It is
necessary to study the functions, such as gelationand thermal
properties, and the SDS-PAGE behavior of pork protein and
replacers.The purpose of this study was to investigate the
effects of the meat proteinsources,such as chicken, beef, rabbit
and tuna, and non-meat protein sources(including soybean protein
isolate, gluten, whey protein, sodium caseinate and egg white)
on the gelation and thermal properties of pork paste. The SDS-
PAGEelectrophoresis was also used to elucidate the changes of
different protein sources after their combination and cooking.
Meat proteins and non-meat proteins were added into pork paste
for DSC,rheological properties analysis and SDS-PAGE
electrophoresis. The ratio of pork and meat proteins used in
this research was 1:1(w/w). The amount of addition of non-meat
proteins was 2.5% or 5%. A 2.5% NaCl was added to all samples
and minced for 5 min at 4℃. On the measurements of rheological
properties, porkpaste, all meat proteins and the mixtures were
heated in a water bath (70℃) for 15 min. Moreover, pork paste,
all non-meat proteins and the mixtures were heated at 70℃ or
100℃ for 15 min, separately. Results were as follows: The
gel strength, breaking intension and hardnessof tuna and chicken
were the highest values while beef and rabbit had the lowest gel
strength, breaking intension and hardnss among the different
meat pastes. The gel strength, breaking intension and hardness
of pork paste with chicken and tuna increased but with beef and
rabbit decreased when compared to pork paste.Pork paste with
various non-meat proteins by different ratios had lower gel
strength, breaking intension and hardness. Whatever the samples
were cooked at 70℃ or 100℃, the pork paste with egg white had
the highest gel strength, breaking intension and hardness, the
lowest values were found on the pork paste with sodium
caseinate. The gel properties of pork paste with non-meat
proteins cooked at 100℃ were better than those cooked at 70℃.
And under the same heating temperature, the gel properties of
pork paste with 2.5% non-meat proteins were better than the lots
with 5%. The DSC analysis showed that all meat proteins had
three denaturation temperatures (Tm) while the denaturation
temperatures of non-meat proteins were higher. The DSC
thermograms of mixtures were similar to a combination of the
thermograms of pork protein and meat proteins or non-meat
proteins, individually. Addition of salt decreased the Tm and △
H of meat proteins while the Tm of non-meat proteins seemed to
increase for addition of salt, but the changes werenot
significant. From the SDS-PAGE analysis, the SDS-PAGE
patterns of mixtures were equal to a combination of pork and
meat proteins or non-meat proteins, separately.
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