Sameli Nikoletta, Sioziou Eleni, Bosnea Loulouda, Kakouri Athanasia, Samelis John
Dairy Research Department, Institute of Technology of Agricultural Products, Hellenic Agricultural Organization "DIMITRA", Katsikas, 45221 Ioannina, Greece.
Foods. 2021 Nov 30;10(12):2946. doi: 10.3390/foods10122946.
Although fresh whey cheeses are prone to rapid deterioration, mainly by psychrotrophic Gram-negative bacteria and lactic acid bacteria (LAB), data on the specific spoilage species in traditional Greek whey cheeses are scarce. Therefore, this study quantified growth and characterized the primary spoilage bacteria in fresh Anthotyros whey cheeses stored at 4 °C in a vacuum for 40 days, without or with an added 5% (/) of an enterocin A-B-P crude extract (CEntE). Psychrotrophic spp., spp., spp. and spp. grew faster than LAB during early storage. However, LAB outgrew the Gram-negative bacteria and prevailed by mid to late storage in all cheese batches, causing a strong or milder batch-dependent natural acidification. Two major non-slime-producing and two minor biotypes of -like bacteria, all identified as by 16S rRNA sequencing, dominated the LAB association (76.7%), which also included four subdominant biotypes (10.9%), one biotype (3.3%) and few (1.6%), mesophilic (0.8%) and (0.8%). Growth and distribution of LAB and Gram-negative species were strongly batch-dependent and plant-dependent. The CEntE neither retarded growth nor altered the whey cheese spoilage association but enhanced LAB growth and the declines of Gram-negative bacteria by late storage.
尽管新鲜乳清奶酪易于迅速变质,主要是由嗜冷革兰氏阴性菌和乳酸菌(LAB)引起,但关于传统希腊乳清奶酪中特定腐败菌的资料却很匮乏。因此,本研究对新鲜的Anthotyros乳清奶酪在4℃真空条件下储存40天,未添加或添加5%(/)的肠球菌素A - B - P粗提物(CEntE)时的细菌生长情况进行了量化,并对主要腐败菌进行了表征。在储存初期,嗜冷菌属、假单胞菌属、不动杆菌属和黄杆菌属的生长速度比乳酸菌快。然而,在所有奶酪批次中,乳酸菌在储存中期至后期超过了革兰氏阴性菌并占主导地位,导致了强烈或较温和的批次依赖性自然酸化。通过16S rRNA测序鉴定为嗜热栖热菌的两种主要不产黏液型和两种次要生物型主导了乳酸菌群落(76.7%),该群落还包括四种次要嗜热栖热菌生物型(10.9%)、一种嗜热栖热菌生物型(3.3%)以及少量嗜热栖热菌(1.6%)、嗜温栖热菌(0.8%)和栖热菌(0.8%)。乳酸菌和革兰氏阴性菌的生长及分布强烈依赖于批次和工厂。CEntE既没有延缓生长,也没有改变乳清奶酪的腐败菌群,但在储存后期促进了乳酸菌的生长并使革兰氏阴性菌数量减少。