Banca de QUALIFICAÇÃO: JÉSSICA DA SILVA CAMPOS
Uma banca de QUALIFICAÇÃO de MESTRADO foi cadastrada pelo programa.DISCENTE : JÉSSICA DA SILVA CAMPOS
DATA : 07/12/2018
HORA: 09:00
LOCAL: Sala de Reuniões do CB
TÍTULO:
ISOLATION AND TERMORRESISTENCE OF YEAST OF THE GENUS Candida ISOLATED OF RAW MILK
PALAVRAS-CHAVES:
Yeasts. Candida. Pasteurization slow and fast. Boil
PÁGINAS: 86
GRANDE ÁREA: Ciências Biológicas
ÁREA: Microbiologia
SUBÁREA: Microbiologia Aplicada
ESPECIALIDADE: Microbiologia Médica
RESUMO:
Milk is considered an excellent culture medium because it is an environment suitable for the development of several microorganisms. Therefore, raw milk intake may be a potential route of transmission of zoonoses, which justifies the need to evaluate their suitability to human consumption by analyzing their microbial content. One of the main microbial agent contaminant of milk is yeast of genus Candida, which is associated with pathologies in humans and animals. In this study, 23 samples of raw milk type B, collected by natural or mechanical milking, stored in collective tanks at dairy farms of Grande Natal and nearby, were analyzed . Twenty samples of milk marketed directly to consumers in the city of Ceará-Mirim, were also analyzed, aiming to compare these products for the presence, quantity and types of yeast species of the genus Candida, as well as to trace the susceptibility profile to the antifungals. All isolated species were submitted to slow (62-64° C/30 minutes) and fast (72-75°C/ 20 seconds) pasteurization tests as well as to boiling. Fifty yeast strains of the following species were isolated: C. tropicalis 14 (28%); C. albicans 7 (14%); C. glabrata 6 (12%); C. krusei 6 (12%); C. parapsilosis 6 (12%) and C. guilliermondii 3 (6%). Five isolates showed antifungal resistance. The samples isolated from the collective cooling tanks were quantified and had an overall median of 37 x 102 U.F.C./mL, being 33 102 2 U.F.C./mL in milk collected by manuals milking and 80.5 x 102 U.F.C./mL in milk collected by mechanical milking, both stored under the same conditions. Samples obtained from the clandestine milk trade in nature in Ceará-Mirim were quantified and presented a median of 20 x 102 U.F.C./mL. Regarding the pasteurization tests, 78% of the isolates resisted fast pasteurization and 70% resisted boiling. However, none of the isolates was resisted heat treatment in slow pasteurization. It was concluded that the milk collected through mechanical milking and stored in collective cooling tanks showed higher contamination indexes with yeast of genus Candida, compared to the samples of milk collected by manual milking submitted to the same conditions of storage. Rapid pasteurization and boiling, which is the most routinely used procedure to reduce the contamination of milk and its derivatives, were not efficient for this purpose. On the other hand, the slow pasteurization showed 100% efficiency for the elimination of milk yeasts.
MEMBROS DA BANCA:
Interno - 348473 - JOSE VERISSIMO FERNANDES
Interno - 1452833 - MARIA CELESTE NUNES DE MELO
Interno - 1714290 - RENATO MOTTA NETO
Externo ao Programa - 2121234 - VANIA SOUSA ANDRADE