Development of a synbiotic \'petit-suisse\' cheese

Author(s)

Haissa Roberta Cardarelli

• Document type: Doctoral Thesis
• Press: São Paulo.
• Institution: Universidade de São Paulo (USP). Conjunto das Químicas (IQ e FCF) (CQ/DBDCQ)
• Defense date: 2006-08-04

Examining board members

Susana Marta Isay Saad; Inar Alves de Castro; Ariene Gimenes Fernandes Van Dender; Bernadette Dora Gombossy de Melo Franco; Ana Lúcia Barreto Penna

• Advisor: Susana Marta Isay Saad

Abstract

Due to the potential synergy between probiotics and prebiotics, dairy products containing a combination of these ingredients are often referred to as synbiotic, providing the beneficial effects of the probiotics combined with the effect of selectively stimulating the growth and/or activity of bifidobacterium in the colon. The purpose of this study was to develop a synbiotic petit-suisse cheese, supplemented with the probiotics Lactobacillus acidophilus and Bifidobacterium lactis and the prebiotics inulin, oligofructose and honey; to monitor the viability of the probiotics and the starter, the concentration of fructans, and also the sensory acceptance and physico-chemical parameters during refrigerated storage (4±1°C) for up to 28 days; to optimize the mixtures involving the prebiotic ingredients, in order to guarantee good probiotic viability and potential prebiotic effects, together with to satisfactory technological and sensory properties. The formulations were developed according to the surface response methodology for mixtures including three factors: oligofructose, inulin and honey. The prebiotics were combined in different proportions (to achieve 10% of total mixture), and 7 trials plus a control trial were obtained (T1 to T8). Probiotic populations were always above the minimum counts suggested for providing health benefits, and varied from 7.20 up to 7.69 log cfu g-1 (B. lactis) and from 6.08 up to 6.99 log cfu g-1 (L. acidophilus). The pH values decreased and the acidity values increased significantly during storage, and were statistically different in the various trials (P<0.05), due to the acidifying effect of the organisms present. The moisture remained stable during storage and also varied statistically in the trials (P<0.05). Instrumental texture profile was greatly influenced by inulin, resulting in firmer, more cohesive and adhesive products, and with higher gumminess. Oligofructose and honey added as sole ingredients produced a less firm, adhesive and gummy cheese. The pH influenced the instrumental firmness, adhesiveness and gumminess negatively, and cohesiveness positively. There was no significant difference in sensory acceptance for the consumer panel between the different trials, except after 28 days of storage (P<0.05). The acceptance was significantly higher for cheeses supplemented with oligofructose (T1) and oligofructose plus inulin (T4), whereas the control (T8) was less accepted. The results always ranged from like slightly to like moderately. Acceptability increased during storage, though significantly (P<0.05) only for cheeses supplemented with oligofructose and/or inulin. Taste was the most preferred attribute for trials T1 (oligofructose), T3 (honey), and T5 (oligofructose plus honey) and less preferred for T8 (control). Texture attribute was always the least preferred, due to the \"dust\" present. All cheese trials, except T3 (honey), can be considered prebiotic, according to the recommended ingestion of 4 to 5 g day -1 of fructans for a 100g daily portion. The response surface methodology, applied to optimize probiotic viability, instrumental firmness, fructans content and cost, resulted in an optimum mixture containing 25% oligofructose, 70% inulin and 5% honey and global desirability of 99.55%. (AU)