Use of RAPD-PCR and TTGE for the evaluation of biodiversity of whey cultures for Grana Padano cheese.
OBJECTIVE
This work was carried out in order to evaluate the microbial diversity of whey cultures collected from different Grana Padano cheese plants in Veneto region (north-east Italy) by means of RAPD-PCR and Temporal Temperature Gradient Gel Electrophoresis (TTGE) analysis.


RESULTS
Lactobacillus helveticus was the dominant species among isolated thermophilic lactobacilli. RAPD-PCR with primers M13 and D8635 resulted a suitable method for typing Lact. helveticus at strain level. Thirteen different Lact. helveticus biotypes were detected in the seven whey cultures studied with one biotype present in all the whey cultures. Besides Lact. helveticus, Lact. delbrueckii subsp. lactis was the main microbial species detected by TTGE.


CONCLUSIONS
RAPD-PCR resulted very useful in studying Lact. helveticus biodiversity; furthermore, TTGE analysis allowed to detect the dominant thermophilic microflora characteristic of Grana Padano cheese whey cultures.


CONCLUSIONS
By the combined used of RAPD-PCR and TTGE it could be possible to follow the behaviour in strain or species composition of whey cultures during time.
Andrighetto
C
C
Veneto Agricoltura, Istituto per la Qualità e le Tecnologie Agroalimentari, Thiene (VI), Italy. cristian.andrighetto@venetoagricoltura.org
Marcazzan
G
G
Lombardi
A
A
D015373:Bacterial Typing Techniques; D044822:Biodiversity; D002611:Cheese / Q000382:microbiology*; D003470:Culture Media; D004269:DNA, Bacterial / Q000032:analysis; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods*; D007778:Lactobacillus / Q000145:classification* / Q000235:genetics / Q000254:growth & development; D019105:Random Amplified Polymorphic DNA Technique / Q000379:methods*
D003470:Culture Media; D004269:DNA, Bacterial