03487naa a2200313 a 450000100080000000500110000800800410001902400310006010000160009124501650010726000090027250000950028152024780037665000190285465000100287365000130288365300090289665300200290565300090292565300210293465300140295565300220296965300150299170000180300670000180302470000150304270000150305777301010307210549072021-03-11       2016    bl uuuu     u00u1 u    #d7 a10.2527/jas.2016-02902DOI1 aLUZARDO, S.  aEffect of packaging during storage time on retail display microbial population of beef strip loins from two different production systems.h[electronic resource]  c2016  aArticle history: Received 08 January 2016; Accepted 25 March 2016; Published 01 June 2016.  aTwo studies were conducted to evaluate the influence of packaging during storage of strip loins (to simulate export shipment) from steers fattened on intensive grazing systems (Uruguay; UR) or on a high-concentrate diet (United States; US) on retail display life microbial growth. Four or 3 different packaging treatments were applied to UR and US strip loin roasts or steaks during 35 d of storage; treatments were applied 7 d following slaughter. After 35 d of storage, the samples were evaluated during simulated retail display for up to 6 d. In Exp. 1, the treatments were vacuum packaging (VP), low-oxygen modified atmosphere packaging (MAP) with N2 and CO2 (MAP/CO2), low-oxygen MAP with N2 plus CO2 and CO, and VP plus an application of peroxyacetic acid (VP/PAA). In Exp. 2, block 1, the treatments were VP, MAP/CO, and VP with ethyl-N-lauroyl-l-arginate HCl incorporated into the film as an antimicrobial agent (VP/AM). In Exp. 2, block 2, the treatments were VP, MAP/CO2, MAP/CO, and VP/AM. For retail display, VP treatments were sliced and repackaged in PVC overwrap, and MAP treatments were actually PVC overwrap trays that were removed from a master bag with the prescribed gas treatment. Regardless of production system and packaging treatment, mesophilic and psychrotrophic counts of 6.9 to 7.8 and 6.7 to 7.7 log10 CFU/cm2, respectively, were obtained at the end of retail display, except for US samples in Exp. 2 (5.5 to 6.3 log10 CFU/cm2). No  differences (P > 0.05) were detected for Pseudomonas spp. counts among packaging treatments in US steaks at the end of the display time in Exp.1, whereas, for UR steaks, both MAP treatments had lower (P < 0.05) Pseudomonas spp. counts than VP treatments. Pseudomonas spp. counts were lower (P < 0.05) in the MAP/CO2 treatment than in the other 3 treatments in US samples on d 6 of retail display for Exp. 2. At the end of display time and for Exp. 1, US steaks under MAP/CO had greater (P < 0.05) lactic acid bacteria (LAB) counts than samples in both VP treatments; no differences (P > 0.05) among packaging were detected for UR steaks. Both MAP and VP/AM treatments in the US samples for Exp. 2 had lower (P < 0.05) LAB counts on d 6 of display than the VP treatment, but no differences (P > 0.05) were found among packaging treatments for the UR samples. To maximize shelf life (storage and display life) of exported fresh beef, it is critical to minimize bacterial populations during processing and storage.  aALMACENAMIENTO  aCARNE  aENVASADO  aBEEF  aBEEF PRODUCTION  aMEAT  aMICROBIAL GROWTH  aPACKAGING  aPRODUCTION SYSTEM  aSTRIP LOIN1 aWOERNER, D.R.1 aGEORNARAS, I.1 aHESS, A.M.1 aBELK, K.E.  tJournal of Animal Science, 2016gv. 94, p. 2624-2636. Doi: https://doi.org/10.2527/jas.2016-0290