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A method was developed to detect and identify Enterobacter sakazakii in environmental samples. The method is based on selective enrichment at 45+/-0.5 degrees C in lauryl sulfate tryptose broth supplemented with 0.5 M NaCl and 10 mg/liter vancomycin (mLST) for 22 to 24 h followed by streaking on tryptone soy agar with bile salts. When exposed to light during incubation at 37 degrees C, E. sakazakii produces yellow colonies within 24 h; identification was confirmed by testing for alpha-glucosidase activity and by using API 20E strips. All of the E. sakazakii strains tested (n = 99) were able to grow in mLST at 45+/-0.5 degrees C, whereas 35 of 39 strains of potential competitors, all belonging to the Enterobacteriaceae, were suppressed. A survey was carried out with 192 environmental samples from four different milk powder factories. Using this new protocol, E. sakazakii was isolated from almost 40% of the samples, whereas the reference procedure (enrichment in buffered peptone water, isolation on violet red bile glucose agar, and biochemical identification of randomly chosen colonies) only yielded 26% positive results. This selective method can be very useful for the rapid and reliable detection of E. sakazakii in environmental samples.

Enterobacter sakazakii can be present, although in low levels, in dry powdered infant formulae, and it has been linked to cases of meningitis in neonates, especially those born prematurely. In order to prevent illness, product contamination at manufacture and during preparation, as well as growth after reconstitution, must be minimized by appropriate control measures. In this publication, several determinants of the growth of E. sakazakii in reconstituted infant formula are reported. The following key growth parameters were determined: lag time, specific growth rate, and maximum population density. Cells were harvested at different phases of growth and spiked into powdered infant formula. After reconstitution in sterile water, E. sakazakii was able to grow at temperatures between 8 and 47°C. The estimated optimal growth temperature was 39.4°C, whereas the optimal specific growth rate was 2.31 h ؊1 . The effect of temperature on the specific growth rate was described with two secondary growth models. The resulting minimum and maximum temperatures estimated with the secondary Rosso equation were 3.6°C and 47.6°C, respectively. The estimated lag time varied from 83.3 ؎ 18.7 h at 10°C to 1.73 ؎ 0.43 h at 37°C and could be described with the hyperbolic model and reciprocal square root relation. Cells harvested at different phases of growth did not exhibit significant differences in either specific growth rate or lag time. Strains did not have different lag times, and lag times were short given that the cells had spent several (3 to 10) days in dry powdered infant formula. The growth rates and lag times at various temperatures obtained in this study may help in calculations of the period for which reconstituted infant formula can be stored at a specific temperature without detrimental impact on health.Enterobacter sakazakii is a motile, peritrichous, gram-negative rod that occasionally causes neonatal meningitis and sepsis, with mortality rates of 40 to 80% (3). The recovery of E. sakazakii from samples of commercially available dry powdered infant formulae has been reported (4,8,9). E. sakazakii organisms in infant formula have been associated with outbreaks of meningitis, sepsis, and necrotizing enterocolitis in premature and full-term infants, particularly those with predisposing medical conditions (17). Although the levels of E. sakazakii occurring in dry powdered infant formula are generally very low, reconstituted infant formula is a good medium for growth. When present in dry formula, E. sakazakii may grow during preparation, cooling, storage, and holding of the bottles, increasing the probability of illness. Occasional contamination of dried infant formula during manufacture is a source of the microorganism's occurrence in reconstituted product. However, as E. sakazakii has been detected in various other dry environments (7), contamination may also occur during reconstitution of dried infant formula in hospitals or at home.In order to prevent illness, product contamination at manufacture and/or during preparat...

This paper describes the results of a research project aimed at the conceptual development of an identification system for emerging mycotoxins in European feed and food supply chains of wheat. Basic requirements for such a system were addressed, including the selection of indicators, locating information sources, development of underlying model, and investigation of stakeholders' needs. The selection and ranking of key indicators for identifying emerging mycotoxins was based on a literature review, followed by a structured expert judgment study. The expert study was based on the Delphi technique and used a panel of 43 European experts. The Delphi procedure resulted in a selected set of 12 key indicators for each of three relevant stages of the wheat chain (cultivation; transport and storage; processing). For wheat cultivation, these were: relative humidity/rainfall, crop rotation, temperature, tillage practice, water activity in the kernels, crop variety, harvest conditions, changes in fungal populations, fungicide use, plant health, regional infection pressure and food safety awareness. For the majority of the selected indicators, information sources were identified in specific European countries. However, most sources are not readily accessible and particular data is lacking. A theoretical concept for a model underlying the envisioned emerging mycotoxin identification system has been developed. The model links the key indicators and their information sources to aid and promote identification of emerging mycotoxins. It manages different types of information sources and levels of available information. The needs of various stakeholder groups regarding the system were investigated by means of two empirical elicitation sessions. The results showed that all stakeholders considered that such a system would be beneficial. One major challenge expected in establishing the system is stakeholder commitment to sharing data and information. This requires great efforts in improving communication and interaction between the key stakeholders.

Enterobacter sakazakii is a motile, peritrichous, gram-negative rod that was previously known as a yellow pigmented Enterobacter cloacae. It is documented as a rare cause of outbreaks and sporadic cases of life-threatening neonatal meningitis, necrotizing enterocolitis, and sepsis. E. sakazakii has been isolated from milk powder-based formulas, and there is thus a need to investigate whether and where E. sakazakii occurs in these manufacturing environments. For this purpose, a simple detection method was developed based on two features of E. sakazakii: its yellow pigmented colonies when grown on tryptone soy agar and its constitutive alpha-glucosidase, which is detected in a 4-h colorimetric assay. Using this screening method, E. sakazakii strains were isolated from three individual factories from 18 of 152 environmental samples, such as scrapings from dust, vacuum cleaner bags, and spilled product near equipment. The method is useful for routine screening of environmental samples for the presence of E. sakazakii.