Título:	Qualidade microbiológica e físico-química de morango (Fragaria x ananassa Duch) exposto ao gás ozônio durante o armazenamento
Autor(es):	Alves, Hanna
Orientador(es):	Alencar, Ernandes Rodrigues de
Assunto:	Gás ozônio Morango
Data de publicação:	30-Mar-2017
Data de defesa:	23-Fev-2017
Referência:	ALVES, Hanna. Qualidade microbiológica e físico-química de morango (Fragaria x ananassa Duch) exposto ao gás ozônio durante o armazenamento. 2017. xvi, 49 f., il. Dissertação (Mestrado em Agronomia)—Universidade de Brasília, Brasília, 2017.
Abstract:	The strawberry stands out for being widely consumed throughout the country, due to its characteristics appreciated by consumers, such as flavor, color, odor, texture and sweetness. Its use is diverse, ranging from the consumption in natura, to the manufacture of jellies, sweets, pulps and yogurts. The safety of the product should be ensured with regard to physical, chemical and microbiological quality. Several sanitizers are used in the food industry, but more and more it is necessary to introduce products that adapt to the new reality demanded by the market. Technology has been sought that is sustainable, in view of even the impact on the environment. Ozone appears as an alternative to traditional sanitizers. It has presented high capacity of inactivating microorganisms due to its high oxidative power. It is a gas that does not generate toxic waste in food and must be produced locally. In this context, it is extremely important to study the binomial gas concentration and exposure period for each food, in order to inactivate the undesirable microorganisms without significantly altering the physical and chemical characteristics of the food. The objective of this work was to evaluate the microbiological and physico-chemical quality of strawberries exposed to the ozone gas in different concentrations and stored for six days under refrigeration (5 ºC). Strawberries of the "Portola" variety were purchased directly from the producer. Ozone gas was obtained by means of an ozone generator based on the Barrier Discharge method. Concentrations equivalent to 0, 4, 9, 14 and 18 mg L-1, flow rate of 1 L min-1 were tested at 25 ° C for 30 min with three replicates. Regarding the microbiological quality, the presence of Salmonella spp. and total coliforms, E. coli, molds and yeasts and aerobic mesophiles were quantified. Regarding the physical-chemical quality, mass loss was analyzed; Titratable total acidity; Total soluble solids; PH; Total soluble solids ratio and titratable total acidity; And coloring of the fruits. A completely randomized design (DIC) was used in 5X4 Factorial Scheme, with five treatments and four storage periods (0, 2, 4 and 6 days), with three replications. No evidence of Salmonella spp. and E. coli, in fruits submitted or not to ozonization. The low and irregular count of total coliforms in the fruits did not allow to infer about the capacity of the ozone to inactivate microorganisms of this group. Ozone was efficient in the control of molds and yeasts and aerobic mesophiles in strawberries during storage. After the ozonation, ocher and yeast counts were 3.5 log lower cycles, comparing the results obtained in the ozonized fruits with those related to the non-ozonated fruits During storage, the counts of molds and yeasts in the ozonated fruits remained lower than those obtained in non - ozonated fruits. A similar trend was observed for aerobic mesophiles. Immediately after ozonization, it was possible to obtain a reduction of more than 4.0 log cycles in the count of aerobic mesophiles, when compared with the results obtained in fruits not exposed to the gas. In general, under the conditions adopted at work, ozone did not adversely affect the physical-chemical quality of strawberries. On the other hand, there was a lower loss of mass of the ozonated fruits when the concentration of exposure to the gas was higher and the values of total soluble solids and of the relation between total soluble solids and titratable total acidity were observed when the concentration of 4 mg L-1, regardless of the storage period. In addition, there was a tendency to maintain the titratable total acidity along the storage, at the gas concentration of 18 mg L-1. Regarding the color difference, a greater increase was observed as the concentration of the gas was increased throughout the storage. It was concluded that ozone is an important antimicrobial agent, and under the conditions adopted in the work caused reduction of undesirable microorganisms. Gas also did not interfere with most of the physicochemical parameters evaluated. It is worth noting that it is important to continue the research with the use of this gas, in such a way that the use of this technology is widespread in the food industry.
Unidade Acadêmica:	Faculdade de Agronomia e Medicina Veterinária (FAV)
Informações adicionais:	Dissertação (mestrado)—Universidade de Brasília, Programa de Pós-Graduação em Agronomia, Faculdade de Agronomia e Medicina Veterinária, 2017.
Programa de pós-graduação:	Programa de Pós-Graduação em Agronomia
Licença:	A concessão da licença deste item refere-se ao termo de autorização impresso assinado pelo autor com as seguintes condições: Na qualidade de titular dos direitos de autor da publicação, autorizo a Universidade de Brasília e o IBICT a disponibilizar por meio dos sites www.bce.unb.br, www.ibict.br, http://hercules.vtls.com/cgi-bin/ndltd/chameleon?lng=pt&skin=ndltd sem ressarcimento dos direitos autorais, de acordo com a Lei nº 9610/98, o texto integral da obra disponibilizada, conforme permissões assinaladas, para fins de leitura, impressão e/ou download, a título de divulgação da produção científica brasileira, a partir desta data.
DOI:	http://dx.doi.org/10.26512/2017.02.D.23150
Aparece nas coleções:	Teses, dissertações e produtos pós-doutorado

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