Hugo L.A. Silva

Partial substitution of NaCl by KCl and addition of flavor enhancers on probiotic Prato cheese: A study covering manufacturing, ripening and storage time

Cheese is a suitable matrix to deliver probiotic strains but it contains a high amount of sodium. The effect of partial substitution of NaCl by KCl and the addition of flavor enhancers (l-arginine, yeast and oregano extract) on probiotic Prato cheese was investigated after 1, 30, and 60 d of refrigerated storage (immediately after manufacturing, and during ripening and storage). Microbiological (lactic acid bacteria and probiotic Lactobacillus casei 01 counts and survival under gastrointestinal conditions), physicochemical (pH, proteolysis, fatty acids), bioactivity (antioxidant effect and angiotensin I-converting enzyme inhibitory activity), rheological, and water mobility by means of time domain low-field nuclear magnetic resonance were investigated. Significant changes in probiotic survival were observed; however, the sodium reduction and the addition of flavor enhancers did not constitute an obstacle to L. casei 01 (>108 CFU/g) during storage. Slight changes were observed in proteolysis, bioactivity, water mobility, texture profile, and fatty acids of the cheeses as a function of the flavor enhancer added. The sodium reduction and the supplementation of Prato cheese with probiotic cultures may be an effective alternative to the production of a potentially functional cheese.

Assessing the effects of different prebiotic dietary oligosaccharides in sheep milk ice cream

The objective of this study was to assess the effects of different prebiotic dietary oligosaccharides (inulin, fructo-oligosaccharide, galacto-oligossacaride, short-chain fructo-oligosaccharide, resistant starch, corn dietary oligosaccharide and polydextrose) in non-fat sheep milk ice cream processing through physical parameters, water mobility and thermal analysis. Overall, the fat replacement by dietary prebiotic oligosaccharides significantly decreased the melting time, melting temperature and the fraction and relaxation time for fat and bound water (T22) while increased the white intensity and glass transition temperature. The replacement of sheep milk fat by prebiotics in sheep milk ice cream constitutes an interesting option to enhance nutritional aspects and develop a functional food.

The addition of inulin and Lactobacillus casei 01 in sheep milk ice cream

The effect of the Lactobacillus casei 01 and inulin addition on sheep milk ice cream during storage (-18 °C, 150 days) was investigated. Control, probiotic and synbiotic ice cream (10% w/w sheep milk cream; 10% w/w sheep milk cream, L. casei 01, 6 log CFU/mL; 10% w/w inulin, L. casei 01, 6 log CFU/mL, respectively) were manufactured. Microbiological counts (probiotic count, survival after in vitro gastrointestinal resistance, Caco-2 cell adhesion), bioactivity and microstructure were analysed. Physical and textural characteristics, colour parameters, thermal analysis and organic acids/volatile compounds were also evaluated. All formulations supported L. casei 01 viability and maintained above the minimum therapeutic level (>6 log CFU/mL) during storage. Inulin did not affect L. casei 01 survival after the passage through simulated gastrointestinal tract and adhesion to Caco-2 cells while improved the ACE-inhibitory and antioxidant activity. L. casei 01 addition produced several volatile compounds, such as carboxylic acids, alcohols, aldehydes and ketones. Also, scanning electron microscopy showed an interaction between probiotic bacteria and inulin fibre on synbiotic ice cream and the adhesion of L. casei to Caco-2 cells was observed.

Sensory evaluation of ovine milk yoghurt with inulin addition

The purpose of this study was to elaborate prebiotic yoghurt using ovine milk and different inulin concentrations (0, 2 and 6%). Samples were submitted to laboratory analysis and two sensory tests with 100 consumers. The results of apparent viscosity and firmness determined by instrumental analysis of each yoghurt and control differed significantly. Just-About-Right showed consistency as the main attribute that varied in treatments. According to penalty analysis, prebiotic yoghurt containing 6% inulin had minor penalties, which indicates its advantage in the quest to better consumer demands. Hence, this treatment demonstrated better results as well as the many prebiotic benefits associated with an adequate fibre amount.

Effect of sodium reduction and flavor enhancer addition on probiotic Prato cheese processing

The effect of partial substitution of NaCl with KCl and the flavor enhancers addition (arginine, yeast extract and oregano extract) on Probiotic Prato cheese processing with (L. casei 01, 7logCFU/mL) was investigated. Microbiological (lactic acid bacteria and probiotic counts), physicochemical (proximate composition, pH, proteolysis), bioactivity (antioxidant and angiotensin I-converting enzyme inhibitory activity), rheological (uniaxial compression and creep tests), water mobility (time domain low field magnetic resonance), microstructure (scanning electron microscopy) and sensory evaluation (consumer test) were performed. Sodium reduction and flavor enhancers addition did not constitute an obstacle to the survival of lactic and probiotic bacteria. Proximate composition, antioxidant and angiotensin I-converting enzyme inhibitory activity, and the rheological parameters were affected by the addition of flavor enhancer. No change in the fatty acid profile of cheeses was observed while good performance in the consumer test was obtained by the addition of yeast extract and oregano extract. Prato cheese can be an adequate carrier of probiotics and the addition of different flavor enhancers can contribute developing this functional product in the cheese industry.

Características morfofisiológicas de biótipos de Euphorbia heterophylla com resistência a diferentes mecanismos de ação herbicida

Weed resistance to herbicides is one of the major barriers to agriculture worldwide. In Brazil, Euphorbia heterophylla (EPHHL) is especially known for presenting resistance to more than one herbicide action mechanism. This work was carried out to identify morphophysiological characteristics and ecological adaptability between Euphorbia heterophylla biotypes with multiple resistance to ALS inhibitors and PROTOX, and with resistance only to ALS inhibitors and susceptible from Southwestern Parana. The experiment was conducted in a greenhouse and arranged in a completely randomized design, with four replications. The morphophysiological characteristics evaluated were: dry matter of leaves + cotyledons, roots, stems+petioles and total, plant height, number of branches per plant, leaf area and number of leaves per plant. In determinations made at a later time, biotype S presented smaller dry matter of leaves+cotyledons, stems+petioles and total, as well as smaller leaf area, number of leaves per plant and height than biotypes R to ALS and R to Protox.

Sodium reduction and flavor enhancer addition in probiotic prato cheese: Contributions of quantitative descriptive analysis and temporal dominance of sensations for sensory profiling

Prato cheese, a typical ripened Brazilian cheese, contains high levels of sodium, and the excess intake of this micronutrient is associated with hypertension and cardiovascular diseases. A technological alternative to reduce the sodium content in foods is to replace NaCl with KCl and the addition of flavor enhancers. The present study aimed to combine quantitative descriptive analysis (QDA) and temporal dominance of sensations (TDS) to assess the sensory profile of reduced-sodium probiotic prato cheese with the addition of flavor enhancers. Five formulations of probiotic prato cheese were manufactured using 1% (wt/wt) salt as follows: C1 (100% NaCl), C2 (50:50 NaCl:KCl), C3 (50:50 NaCl:KCl + 1% arginine), C4 (50:50 NaCl:KCl + 1% yeast extract), and C5 (50:50 NaCl:KCl + 1% oregano extract). Both methods indicated that the addition of flavor enhancers modified the sensory profile of the reduced-sodium probiotic prato cheese. The QDA revealed that flavor enhancers-in particular, yeast and oregano extract-increased the saltiness of samples C4 and C5, respectively, and that the other flavor enhancer, arginine (sample C3), most modified the attributes of prato cheese. The TDS dominance curves revealed that the addition of yeast extract (sample C4) had a positive effect on cheese flavor because it minimized the bitter taste perception resulting from the addition of potassium chloride. Overall, QDA and TDS used together provided interesting insights for establishing the sensory profile of reduced-sodium probiotic prato cheese.

Brazilian cheeses: A survey covering physicochemical characteristics, mineral content, fatty acid profile and volatile compounds

Chemical characteristics, mineral levels (Ca, Fe, K, Mg, Na, Zn, Cr, Cu, and Mn), fatty acid profile and volatile compounds of typically Brazilian cheeses (Minas Frescal, Minas Padrão, Prato and Coalho, n = 200, equally distributed) were investigated. The cheeses have proven to be a source of Ca, Cu and Zn (>15% RDI/30 g), with low atherogenic and thrombogenic indices, with ethanol as the main alcohol and butanoic acid as the main acid, and moderate to high sodium content. Minas Frescal cheese presented lower nutritional value (proteins, lipids, and minerals), while Prato cheese had a higher fatty acids concentration, including conjugated linoleic acid (0.013 g 100 g-1). Coalho cheese had a higher acetic acid level, while citric acid and lactic acid predominated in Minas Padrão cheese. The results provide essential information for Brazilian consumers, demonstrated that the manufacturing conditions are heterogeneous and suggested that a standardized manufacturing protocol for dairy processors is needed.