title: Shelf life of ostrich (Struthio camelus) liver stored under different packaging conditions.
abstract: Ostrich (Struthio camelus) liver is an important edible meat by-product. However, it has a low commercial value, and it is underutilized. The present study was conducted to establish the shelf life of ostrich liver, stored at 2 +/- 1 degrees C for 18 days, under different packing conditions. Fresh livers were sliced and packed under air exposure, vacuum, and modified atmosphere (MA: 80% CO2 plus 20% N2). Shelf-life evaluation was based on color, lipid and hemopigment oxidation, microbial counts, and sensory assessment of odor and color. Samples stored under air exposure showed the highest lipid and hemopigment oxidation rate, which was detected by higher thiobarbituric acid reactive substances values and metmyoglobin percentage and lower heme iron content than livers stored under vacuum or MA. On the basis of aerobic bacteria counts, the shelf life of ostrich liver stored under aerobic conditions would be 7 days, whereas under vacuum or MA, it would be 14 days. In livers stored under anaerobic conditions (vacuum or MA packed), lactic acid bacteria represented a significant proportion of the spoilage microbiota. Minimal changes in color perception were also obtained in vacuum-packed samples at the end of the storage period. In air-packed samples, high levels of off-odors were already perceived during the first 6 days of storage, whereas in livers stored under anaerobic conditions (vacuum and MA), these levels of off-odor were not yet perceived at that time.
authors.affiliation: Agrofood Technology Department, Miguel Hernández University, Orihuela 03312 (Alicante), Spain. j.fernandez@umh.es
authors.forename: Juana
authors.initials: J
authors.lastname: Fernández-López
authors.forename: Ana
authors.initials: A
authors.lastname: Yelo
authors.forename: Estrella
authors.initials: E
authors.lastname: Sayas-Barberá
authors.forename: Esther
authors.initials: E
authors.lastname: Sendra
authors.forename: Casilda
authors.initials: C
authors.lastname: Navarro
authors.forename: José Angel
authors.initials: JA
authors.lastname: Pérez-Alvarez
mesh_terms: D000818:Animals; D002245:Carbon Dioxide / Q000378:metabolism; D015169:Colony Count, Microbial; D005516:Food Microbiology; D018857:Food Packaging / Q000379:methods*; D005519:Food Preservation / Q000379:methods*; D015227:Lipid Peroxidation; D008099:Liver / Q000382:microbiology*; D009584:Nitrogen / Q000378:metabolism; D009812:Odorants / Q000032:analysis; D010084:Oxidation-Reduction; D010100:Oxygen / Q000378:metabolism; D010858:Pigmentation; D020310:Struthioniformes; D017392:Thiobarbituric Acid Reactive Substances / Q000032:analysis; D013997:Time Factors; D014618:Vacuum
chemical_list: D017392:Thiobarbituric Acid Reactive Substances; D002245:Carbon Dioxide; D009584:Nitrogen; D010100:Oxygen