effects of feed and storage time
Li, Shengjie
(2016).
Quality of muscle foods.
Diss. (sammanfattning/summary)
Uppsala :
Sveriges lantbruksuniv.,
Acta Universitatis Agriculturae Sueciae, 1652-6880
; 2016:18
ISBN 978-91-576-8538-4
eISBN 978-91-576-8539-1
[Doctoral thesis]
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Abstract
The overall aim of this thesis was to investigate the effects of feed and storage time on meat quality.
To study the effect of feed, chicken were fed seven steam-pelleted or nonpelleted rapeseed (RS) diets with different RS inclusion levels (0, 80, 160, and 240 g/kg) for 34 days, and the dietary effects on meat yield, fatty acid composition in meat, and the expression of lipid metabolism-related genes in liver were determined. Feeding with steam-pelleted diets with high inclusion of RS (160 or 240 g/kg) significantly increased the content of n-3 long chain polyunsaturated fatty acids (n-3 LC-PUFA) in meat, without compromising the meat yield and total fatty acid content. The increased intake of α-linolenic acid enabled higher conversion into n-3 LC-PUFA. Therefore, feeding broiler chicken steam-pelleted diet with high RS inclusion can be a feasible strategy to increase human intake of n-3 LC-PUFA without compromising meat yield.
The effect of storage time on meat color, microbial growth, and lipid oxidation was studied on beef steaks from Longissimus thoracis et lumborum muscles overwrapped with polyvinyl chloride (PVC) film and stored at 4°C for 0, 4, 7, and 10 days. Microbial spoilage of beef occurred at day 10 as indicated by the total viable count exceeding the threshold of 7 log10 CFU/cm². Pseudomonas spp. and Brochothrix spp. were the prevailing bacteria species when meat was spoiled. Moreover, Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis showed the successive changes in the incidences of different bacteria over time. At day 10, the a* and Chroma decreased and hue angle increased significantly, indicating meat discoloration. Concentrations of spermine, tyramine, and cadaverine were found to be potential spoilage indicators of meat freshness. Lipid oxidation occurred only slightly, which could be attributed to the high content of α-tocopherol in meat. In contrast, the degree of lipid lipolysis increased with storage time as reflected by the increase in the relative content of free fatty acids and decrease in relative content of triacylglycerols.
Authors/Creators: | Li, Shengjie | ||||||||||
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Title: | Quality of muscle foods | ||||||||||
Subtitle: | effects of feed and storage time | ||||||||||
Series/Journal: | Acta Universitatis Agriculturae Sueciae (1652-6880) | ||||||||||
Year of publishing : | 2016 | ||||||||||
Depositing date: | 19 February 2016 | ||||||||||
Number: | 2016:18 | ||||||||||
Number of Pages: | 58 | ||||||||||
Papers/manuscripts: |
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Place of Publication: | Uppsala | ||||||||||
Publisher: | Department of Food Science, Swedish University of Agricultural Sciences | ||||||||||
ISBN for printed version: | 978-91-576-8538-4 | ||||||||||
ISBN for electronic version: | 978-91-576-8539-1 | ||||||||||
ISSN: | 1652-6880 | ||||||||||
Language: | English | ||||||||||
Publication Type: | Doctoral thesis | ||||||||||
Full Text Status: | Public | ||||||||||
Agris subject categories.: | L Animal production > L02 Animal feeding Q Food science > Q04 Food composition Q Food science > Q54 Feed composition | ||||||||||
Subjects: | (A) Swedish standard research categories 2011 > 4 Agricultural Sciences > 401 Agricultural, Forestry and Fisheries > Food Science | ||||||||||
Agrovoc terms: | chickens, cattle, chicken meat, beef, meat quality, proximate composition, polyunsaturated fatty acids, colour, feeds, rapeseed, gene expression, lipolysis | ||||||||||
Keywords: | n-3 LC-PUFA, rapeseed, discoloration, microbial growth, biogenic amine, lipolysis, lipid oxidation | ||||||||||
URN:NBN: | urn:nbn:se:slu:epsilon-e-3236 | ||||||||||
Permanent URL: | http://urn.kb.se/resolve?urn=urn:nbn:se:slu:epsilon-e-3236 | ||||||||||
ID Code: | 13082 | ||||||||||
Faculty: | NJ - Fakulteten för naturresurser och jordbruksvetenskap | ||||||||||
Department: | (NL, NJ) > Dept. of Food Science (until 161231) | ||||||||||
External funders: | Värmeforsk (Stiftelsen för värmeteknisk forskning) | ||||||||||
Deposited By: | Mr. Shengjie Li | ||||||||||
Deposited On: | 22 Feb 2016 09:54 | ||||||||||
Metadata Last Modified: | 10 Sep 2020 13:41 |
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