Valorization of biowastes from sustainable viticulture with bioactive potential: application in functional yogurt.

Seed and peel flours of organic Bordeaux grapes (Vitis labrusca L.), containing phenolics and antioxidant capacity, influenced both the composition and properties of a yogurt. The total phenolic content (TPC) of the yogurts containing 3% of grape seed flour (GSFY) and 3% of the mixture of flours (MFY, containing 50% of seed and 50% of peel grape flours, w/w) were 18.800 ± 1.060 and 19.509 ± 1.216 mg/g of gallic acid equivalents (GAE), respectively, significantly higher than the content of the control formulation (CY, 3.199 ± 0.326 mg GAE/g). The GSFY, MFY and CY exhibited an antioxidant capacity (mean values), respectively, of 0.6100, 0.7833 and zero µmol TEAC/g by the FRAP method; and 3.6658, 2.9217 and 0.2468 µmol TEAC/g by the ABTS method. The yogurts presented typical coloration of each flour and the texture of the yogurts did not vary significantly compared to the CY. Principal Component Analysis (PCA) results distinguished the yogurts containing the grape flours and the control sample, regarding their composition and properties. The grape bioresidues were valorized by obtaining a functional and clean label yogurt.

Relevant safety aspects of raw milk for dairy foods processing.

The concern with food safety in the milk chain begins with the quality of the raw milk. Due to the health hazard that this food can carry when contaminated, the focus of studies has turned to microbiological and chemical contaminants that may be present in raw milk. There is an essential concern about conventional pathogens (Shiga toxin-producing Escherichia coli, Salmonella spp., Listeria monocytogenes, Campylobacter spp., Salmonella spp., and coagulase-positive Staphylococcus spp.) and emerging pathogens (Arcobacter butzleri, Yersinia enterocolitica, Mycobacterium avium ssp. paratuberculosis, Helicobacter pylori, and Cronobacter sakazakii) found in raw milk and dairy products. In addition, a growing public health issue has been raised regarding antimicrobial-resistant pathogens and commensal strains found in milk and dairy products. The antibiotic residues in milk can also damage health, such as allergies, and cause technological problems in dairy products processing. This health issue extends to other chemical contaminants such as heavy metals, pesticides, polycyclic aromatic hydrocarbons, melamine, dioxins, polychlorinated biphenyls, plasticizers, and additives in milk and dairy products. Other chemical substances formed by microorganisms are also of high importance, such as biogenic amines and mycotoxins. Therefore, this chapter aimed to revise and discuss relevant biological and chemical risks to ensure the safety and quality of raw milk and dairy products.

Influence of guabiroba pulp (campomanesia xanthocarpa o. berg) added to fermented milk on probiotic survival under in vitro simulated gastrointestinal conditions.

In fermented milks inoculated with two thermophilic strains (Lactobacillus bulgaricus and Streptococcus thermophilus), guabiroba pulp (Campomanesia xanthocarpa O. Berg) was added in different concentrations: 5% (I5 sample) and 10% (I10 sample), compared to a control sample, with no pulp addition. In these fermented milks, Bifidobacterium BB-12 was added and the samples were submitted to a progressive gastrointestinal simulation in vitro. The cells count was performed, including the survival rates for all the progressive steps of the simulated digestion. Total phenolic content (TPC) and antioxidant activity analysis by FRAP (Ferric Reducing Antioxidant Power) and DPPH (2,2-diphenyl-1-picrylhydrazyl) were performed in all the gastrointestinal steps. Before and during the entire gastrointestinal tract, the Bifidobacterium BB-12 count was 8-9 log CFU g-1, above the recommended for a probiotic product, with a highlight in intestinal colon steps. The I10 sample showed the highest viable cell count, the highest total phenolic content and antioxidant activity throughout the entire gastric steps (p < 0.05). The fermented milk proved to be an effective matrix for the probiotic stability and incorporation of guabiroba components. Bioactive compounds present in the guabiroba pulp may have occasioned a prebiotic and protective effect on Bifidobacterium BB-12 after gastric conditions. The possible bioconversion of these compounds in more active forms can contribute to the absorption in epithelial cells, enhancing fermented milks with guabiroba pulp as important sources of dietary accessible bioactive compounds.

Stability of bifidobacteria entrapped in goat's whey freeze concentrate and inulin as wall materials and powder properties.

Goat's whey was submitted to two cycles of block freeze concentration process, resulting in concentrate 1 and concentrate 2. Concentrate 1 was added with 5 g of inulin and both concentrates were inoculated with Bifidobacterium animalis ssp. lactis BB-12, the concentrates were then denoted as feed solutions 1 and 2, respectively. Feed solutions were spray-dried, resulting in powder 1 and 2. The stability of the bifidobacteria entrapped within the powders was evaluated for both spray-dried powders stored at 4 °C and 25 °C for 60 days. The spray-dried powders were also evaluated in relation to their physical and thermal properties. It was noted that Bifidobacteria displayed increased stability at refrigeration temperature. Analysis of physical properties indicated that the addition of inulin resulted in increased water solubility. However, both spray-dried powders displayed less flowability, as well as a yellow-greenish color. By evaluating the spray-dried powders thermal properties, it was possible to confirm that goat whey concentrates behave as excellent wall materials.

Evaluation of the interaction between microencapsulated Bifidobacterium BB-12 added in goat's milk Frozen Yogurt and Escherichia coli in the large intestine.

Goat milk and goat milk and inulin were used as encapsulating agents of Bifidobacterium BB-12 and applied in Frozen Yogurt (GF2 and GF3, respectively) in order to evaluate the antagonistic effect against Escherichia coli. GF1 is a control containing only Escherichia coli. Simulation of gastrointestinal digestion occurred sequentially. Quantification of Bifidobacterium BB-12 was performed using plate counting while E. coli count was compared with quantification by qPCR with viable and nonviable cell differentiation. The Bifidobacterium BB-12 count was <1.0, 9.23 and 9.11 log CFU g-1 for GF1, GF2 and GF3, respectively. In the ascending colon, all samples showed E. coli counts of approximately 5 log CFU g-1 by plate counting and by qPCR. Throughout the transverse (24 h) and descending colon (48 h) samples GF2 and GF3 showed decrease in E. coli number. GF3 showed higher decrease of E. coli in the descending colon because of inulin bifidogenic characteristic. The production of organic acids by bifidobacteria was directly related to the decrease in the E. coli count. In plate counts, E. coli was not detected for the GF3 sample in the descending colon. However, when quantified by qPCR the sample presented amplification that corresponded to 3 log CFU g-1. In this way, it was possible to observe the phenomenon of the viable but not-culturable cells of E. coli. Finally, it is recommended the microcapsule produced with goat milk and the inulin for application in goat milk products, due to the better antagonist effect against E. coli.