Impacts of post-mortem ageing prior to freezing on technological and oxidative properties of coarse ground lamb sausage in a model system.
OBJECTIVE
The objective of this study was to evaluate the effects of ageing time of lamb loins prior to freezing on technological characteristics and oxidation stability of coarse ground lamb loin sausage using in a model system.


METHODS
Lamb loins (M. longissimus lumborum, n = 25) were aged at -1.5°C for 0, 1, 2, 3, and 8 wk and then frozen for the remaining days (a total of 30 wk). The aged/frozen/thawed lamb loins were ground, and model sausages were formulated with 75% aged/frozen/thawed lamb loin, 25% water, 1.5% sodium chloride (NaCl) and 0.3% sodium tripolyphosphate. The pH and thaw/purge loss of aged/frozen/thawed lamb loins were evaluated, and protein functionality (protein solubility and emulsifying capacity), water-holding capacity and textural properties of model sausages were determined. Cooked model sausages were vacuum-packaged in a plastic bag and displayed under continuous fluorescent natural white light (3°C±1°C). Colour and lipid oxidation of the cooked model sausages were evaluated on 0 and 21 d of display storage.


RESULTS
Ageing prior to freezing had no impact on pH and purge/thaw loss of lamb loins and the colour of cooked sausages (p>0.05) made from the loins. Lamb loins aged for at least 3 wk prior to freezing numerically improved total and myofibrillar protein solubilities (p>0.05) and emulsion activity index (p = 0.009) of meat batter, but decreased cooking loss (p = 0.003) and lipid oxidation (p<0.05) of model sausages.


CONCLUSIONS
This study suggests that post-mortem ageing of raw meat prior to freezing could improve water-holding capacity and lipid oxidative stability of sausage made from the meat.
AgResearch Ltd., Ruakura Research Centre, Hamilton 3240, New Zealand.|Meat Science and Muscle Biology Lab, Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Juhui
J
Choe
Meat Science and Muscle Biology Lab, Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Hyun-Wook
HW
Kim
AgResearch Ltd., Ruakura Research Centre, Hamilton 3240, New Zealand.
Mustafa M
MM
Farouk
AgResearch Ltd., Ruakura Research Centre, Hamilton 3240, New Zealand.|Meat Science and Muscle Biology Lab, Department of Animal Sciences, Purdue University, West Lafayette, IN 47907, USA.
Yuan H
YH
Brad Kim
Ageing; Freezing; Lamb Loin; Lipid Oxidation; Protein Functionality