Abstract:
Fresh meat is commonly packaged in modified atmosphere to decelerate spoilage processes. The applied gas mixture affects the growth of spoilage organisms and selectively shapes the spoilage community. In this study, we investigated the impact of O2 and CO2 on the growth of Photobacterium (P.) phosphoreum and P. carnosum strains in situ on chicken meat by packaging under different modified atmospheres (air, 70% O2/30% CO2, 70% N2/30% CO2, 100% N2). Combination of 70% O2 and 30% CO2 resulted in significant growth reduction of the analyzed strains, suggesting inhibitory effects of both gases in combination. In contrast, 30% CO2 alone had only a minor effect and photobacteria are supposed to have a growth advantage over other meat spoilers in this atmosphere. Additionally, single growth of the strains in the different atmospheres was compared when challenged with the presence of Pseudomonas (Ps.) fragi or Brochothrix (B.) thermosphacta as prominent co-contaminants in different ratios (10:1, 1:1, 1:10). Presence of co-contaminants resulted in increased cell numbers of P. carnosum TMW2.2149 but reduced or unchanged cell numbers of P. phosphoreum TMW2.2103 in most packaging atmospheres. The initial ratio of photobacteria and co-contaminants defined the relative abundance during storage but did not change the type of the interaction. Our results suggest either a commensalistic (P. carnosum) or competitive interaction (P. phosphoreum) of photobacteria and co-contaminants on modified atmosphere packaged chicken, respectively. Furthermore, in a mix comprising seven prominent spoilers, strains of both Photobacterium species prevailed as a constant part of the spoilage microbiome during 7 days of refrigerated storage on chicken meat packaged under O2/CO2 atmosphere.
摘要:
鲜肉通常在改良的气氛中包装以减缓腐败过程。所施加的气体混合物影响腐败生物的生长并选择性地形成腐败群落。在这项研究中,我们研究了O2和CO2对光细菌生长的影响(P.)通过在不同改性气氛(空气,70%O2/30%CO2、70%N2/30%CO2、100%N2)。70%O2和30%CO2的组合导致分析菌株的显著生长减少,表明两种气体组合的抑制作用。相比之下,仅30%的CO2仅具有较小的影响,并且在这种气氛中,发光细菌被认为比其他肉类扰流板具有生长优势。此外,当受到假单胞菌的攻击时,比较了不同气氛中菌株的单一生长(Ps。)fragi或Brochothrix(B.)热球是不同比例(10:1、1:1、1:10)的突出共污染物。在大多数包装气氛中,共污染物的存在导致了P.carnosumTMW2.2149的细胞数增加,但减少或未改变的P.phorosumTMW2.2103的细胞数。光细菌和共污染物的初始比例定义了储存期间的相对丰度,但没有改变相互作用的类型。我们的结果表明要么是共生主义的(P.carnosum)或竞争性互动(P.phosphoreum)在改良气氛包装的鸡肉上的光细菌和共污染物,分别。此外,在包含七个突出破坏者的组合中,在O2/CO2气氛下包装的鸡肉上冷藏7天期间,两种光细菌的菌株都作为腐败微生物组的恒定部分盛行。