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Synbiotic fresh cream-cheese

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Author(s):
Flávia Carolina Alonso Buriti
Total Authors: 1
Document type: Master's Dissertation
Press: São Paulo.
Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
Defense date:
Examining board members:
Susana Marta Isay Saad; Bernadette Dora Gombossy de Melo Franco; Carmen Cecilia Tadini
Advisor: Susana Marta Isay Saad
Field of knowledge: Agronomical Sciences - Food Science and Technology
Indexed in: Banco de Dados Bibliográficos da USP-DEDALUS; Biblioteca Digital de Teses e Dissertações - USP
Location: Universidade de São Paulo. Biblioteca do Conjunto das Químicas; CQ/T/664; B959d
Abstract

Probiotics are live microorganisms that, when administered in adequate amounts, confer a health benefit on the host. Prebiotics are nondigestible carbohydrates that beneficially affect the host by selectively stimulating the growth and/or activity of a limited number of bacteria present in the colon. A product referred as synbiotic is one in which probiotics and prebiotics are combined. The present research aimed to study the viability of obtaining a synbiotic fresh cream cheese produced with the addition of a probiotic culture of Lactobacillus paracasei subsp. paracasei (LBC 82) and of the prebiotic ingredient inulin. Three fresh cream cheese-making trials were produced (5 repetitions of each one): T1 (probiotic) ¡V with Streptococcus thermophilus + Lactobacillus paracasei; T2 (synbiotic) ¡V with St. thermophilus + L. paracasei + inulin; T3 (control) ¡V only with St. thermophilus. Counts of L. paracasei, St. thermophilus, lactic acid bacteria, coliforms, Escherichia coli, Staphylococcus spp., DNAse-positive Staphylococcus, yeasts and moulds, and analysis of pH, titratable acidity, moisture content, water activity and texture profile (two-bite compression tests, employing a TA-XT2 texture analyser), besides determination of fructan content in cheeses T2, proceeded up to 21 days of storage of the products at 4„b1oC. Cheeses were also compared through sensory evaluation after 7 days of storage, using preference-ranking test. No significant differences were detected between cheeses T1, T2 and T3 for titratable acidity, moisture content and water activity (P>0.05). Counts of St. thermophilus remained constant, around 9.5 log cfu/g, in cheeses T1, T2 and T3. Viability of L. paracasei was enough to characterize cheeses T1 and T2 as potentially probiotic, and counts were always above 7 log cfu/g. Contamination levels were always bellow the recommended by Brazilian regulatory standards (except for a DNAse positive Staphylococcus sample of cheeses T3 at day 1), and E. coli was never detected. L. paracasei inhibited the growth of coliforms, Staphylococcus spp. and DNAse-positive Staphylococcus significantly (P<0.05) in cheeses T1 and T2. The presence of inulin in cheeses T2 did not alter the texture profile significantly (P>0.05). No significant changes in the fructan content during storage were observed (P>0.05), and it remained always above 7 g / 100 g. Cheeses T1 were the least preferred in the sensory evaluation and differed significantly from T2 and T3 (P<0.05), due to acidic taste, according to panelists. On the other hand, T2 was the most preferred one, though not significantly different from T3 (P>0.05). The addition of the prebiotic ingredient inulin to fresh cream cheese produced with a potentially probiotic Lactobacillus paracasei strain resulted in a product with appropriate features and with aggregated functional properties. (AU)

FAPESP's process: 02/11294-0 - Synbiotic fresh cheese
Grantee:Flávia Carolina Alonso Buriti
Support Opportunities: Scholarships in Brazil - Master