Losito Francesca, Arienzo Alyexandra, Bottini Giorgia, Priolisi Francesca Romana, Mari Alberto, Antonini Giovanni
Department of Science, Roma Tre University, 00146 Rome, Italy.
MBS S.r.l., 00131 Rome, Italy.
J Dairy Sci. 2014;97(1):46-55. doi: 10.3168/jds.2013-7026. Epub 2013 Nov 13.
Dairy products are characterized by reduced shelf life because they are an excellent growth medium for a wide range of microorganisms. For this reason, it is important to monitor the microbiological quality of dairy products and, in particular, the total viable count and concentration of Escherichia coli, as they are indicators of the hygienic state of these products. In addition, in dairy products such as Mozzarella cheese, it is important to monitor the concentration of lactic acid bacteria (LAB), as they are the major components of starter cultures used in cheese production, contributing to the taste and texture of fermented products and inhibiting food spoilage bacteria by producing growth-inhibiting substances. For these reasons, to ensure the quality and safety of their products, cheese makers should monitor frequently, during fresh cheese production, the concentration of LAB and spoilage bacteria. However, usually, small- to medium-size dairy factories do not have an internal microbiological laboratory and external laboratories of analysis are often too expensive and require several days for the results. Compared with traditional methods, the microbiological survey (MBS) method developed by Roma Tre University (Rome, Italy) allows faster and less-expensive microbiological analyses to be conducted wherever they are necessary, without the need for a microbiological laboratory or any instrumentation other than MBS vials and a thermostat. In this paper, we report the primary validation of the MBS method to monitor LAB concentration in Mozzarella cheese and the analysis, using the MBS method, of total viable count, E. coli, and LAB concentrations in the production line of Mozzarella cheese as well as during the shelf life of the product stored at 20°C. The results obtained indicate that the MBS method may be successfully used by small- to medium-size dairy factories that do not have an internal microbiological laboratory. Using the MBS method, these dairy factories can monitor autonomously the microbiological safety and quality of their products, saving both time and money.
乳制品的保质期较短，因为它们是多种微生物的优质生长培养基。因此，监测乳制品的微生物质量非常重要，特别是总活菌数和大肠杆菌浓度，因为它们是这些产品卫生状况的指标。此外，在马苏里拉奶酪等乳制品中，监测乳酸菌（LAB）的浓度也很重要，因为它们是奶酪生产中使用的发酵剂培养物的主要成分，有助于发酵产品的风味和质地，并通过产生生长抑制物质来抑制食品腐败细菌。出于这些原因，为确保产品的质量和安全，奶酪制造商应在新鲜奶酪生产过程中频繁监测LAB和腐败细菌的浓度。然而，通常中小型乳制品厂没有内部微生物实验室，而外部分析实验室往往成本过高，且需要数天才能得到结果。与传统方法相比，罗马第三大学（意大利罗马）开发的微生物调查（MBS）方法能够在任何需要的地方进行更快、成本更低的微生物分析，除了MBS小瓶和恒温器外，无需微生物实验室或任何仪器。在本文中，我们报告了MBS方法用于监测马苏里拉奶酪中LAB浓度的初步验证，以及使用MBS方法对马苏里拉奶酪生产线以及在20°C储存的产品保质期内的总活菌数、大肠杆菌和LAB浓度进行的分析。获得的结果表明，没有内部微生物实验室的中小型乳制品厂可以成功使用MBS方法。使用MBS方法，这些乳制品厂可以自主监测其产品的微生物安全性和质量，节省时间和金钱。
