High-throughput DNA sequencing (HTS) was used in this study to investigate the microbiota of Plaisentif production, an artisanal antique cheese fabricated in the Italian Alps during the violet's blooming season. The dynamics of the microbiota was described in four production points for nine different producers. The bacteria present in all samples correspond to four phyla: Proteobacteria, Firmicutes, Bacteroidetes, and Acinetobacteria. Of these, Proteobacteria and Firmicutes were the most abundant in milk and curd whereas Firmicutes dominated in cheese samples. The results showed a higher bacterial diversity in the initial steps of cheese making (milk, curd), while the final product presented a lower number of genera mainly represented by lactic acid bacteria. In ripened cheeses, core bacterial community was composed by the genera Lactococcus, Lactobacillus and Streptococcus. Although most of the reads from the final ripened cheese correspond to few LAB, it is still possible to observe some variability between the producers. The HTS revealed that some producers used starters, even if it is not considered by the Plaisentif production's technical policy. The obtained results highlight the great potential of the HTS methodologies in the dairy industry not only from the scientific point of view but also from practical approach

27The interest in donkey milk (DM) is growing because of its functional properties and 28 nutritional value, especially for children with allergies and food intolerances. However, most 29 of the available reports of DM microbiota are based on culture-dependent methods to 30 investigate food safety issues and the presence of lactic acid bacteria (LAB). 31The aim of this study was to determine the composition of DM bacterial communities using a 32 high-throughput sequencing (HTS) approach.

During the last years the interest in donkey milk has increased significantly mainly because of its compelling functional elements. Even if the composition and nutritional properties of donkey milk are known, its microbiota is less studied. This Research Communication aimed to provide a comprehensive characterisation of the lactic acid bacteria in raw donkey milk. RAPD-PCR assay combined with 16S rDNA sequencing analysis were used to describe the microbial diversity of several donkey farms in the North West part of Italy. The more frequently detected species were: Lactobacillus paracasei, Lactococcus lactis and Carnobacterium maltaromaticum. Less abundant genera were Leuconostoc, Enterococcus and Streptococcus. The yeast Kluyveromyces marxianus was also isolated. The bacterial and biotype distribution notably diverged among the farms. Several of the found species, not previously detected in donkey milk, could have an important probiotic activity and biotechnological potential. This study represents an important insight to the ample diversity of the microorganisms present in the highly selective ecosystem of raw donkey milk.

BackgroundAdverse food reactions (AFRs) are defined as abnormal responses to an ingested food or food additive. Diagnosis and treatment of AFRs consist of the complete elimination of these ingredients in the dietary trial. Previous studies have demonstrated the presence of undeclared ingredients in commercial limited-antigen dry food diets that can compromise the results and efficacy of dietary elimination trails. The aim of this study was to assess a selection of commercial canine and feline dietetic limited-antigen wet foods for the potential cross-contamination of animal proteins from origins not mentioned on the label.ResultsEleven canine and feline dietetic limited-antigen wet foods (9 novel animal protein foods, 1 vegetarian and 1 hydrolyzed) were analyzed by polymerase chain reaction (PCR) to detect the presence DNA of animal and vegetal origins. PCR analysis confirmed the contamination of 6 of the 11 (54.5%) limited-antigen wet diets with undeclared animal protein. One of these 6 diets was solely composed of animal protein sources completely unrelated to those declared on the label. None of the foods containing horse meat or fish were contaminated, and neither were the vegetarian or the hydrolyzed food products. Moreover, the results show that had zoological class primers only been used to check for cross-class contaminations, as are generally used in the pet food industry for in-house checks, the apparent contamination rate would have been significantly underestimated: less than 20% (3/11), instead of the actual rate of 54.7% using species-specific primers.ConclusionThis study reveals a high rate of cross-contamination in dietetic limited-antigen wet canine and feline foods, as previously described for dietetic dry limited-antigen foods (reported to be more than 80%). These results add new fuel to the discussion about the potential causes underlying the failure of elimination diets, since animal protein contaminants may actually be present in the commercial dietetic limited-antigen diets. AFRs may therefore occur as a result of inadequate practices in the pet food industry.