Cheese whey, one of the most abundant by-products of the dairy industry, causes economic losses and pollution problems. In this study, deproteinised sweet whey was fermented by Pseudomonas taetrolens LMG 2336 to produce a prebiotic compound (lactobionic acid, LBA). Endotoxins produced by these microorganisms were successfully removed using microfiltration techniques, allowing the fermented whey permeate to be used in the food industry. The fermented whey permeate was used to develop prebiotic edible films by adding two different concentrations of gelatine (0.45 and 0.9 g gelatine g⁻¹ LBA; LBA45 and LBA90). Furthermore, Lactobacillus plantarum CECT 9567 was added as a probiotic microorganism (LP45 and LP90), creating films containing both a prebiotic and a probiotic. The mechanical properties, water solubility, light transmittance, colour, and microstructure of the films were fully characterised. Additionally, the LBA and probiotic concentration in LP45 and LP90 were monitored under storage conditions. The strength and water solubility of the films were affected by the presence of LBA, and though all these films were homogeneous, they were slightly opaque. In LP45 and LP90, the presence of LBA as a prebiotic improved the viability of L. plantarum during cold storage, compared to the control. Therefore, these films could be used in the food industry to coat different foodstuffs to obtain functional products.

To analyze the association between tic disorders and poor academic performance in school-aged children. This was a cross-sectional, observational study conducted in a randomly selected sample of mainstream school-aged children (aged 6-16 years). The sampling frame included different types of schools and educational levels. Children with poor academic performance (eg, repeating a grade, special needs), and tic disorders (defined based on Diagnostic and Statistical Manual of Mental Disorders, 4th Edition, Text Revision criteria) were identified. Children with and without tics and children with and without poor academic performance were compared in terms of clinical features (ie, medical history and neurologic and psychiatric comorbidities), school, and environmental characteristics. Logistic regression analyses were performed using school performance (dependent variable) and tic disorders (independent variable), after adjusting for confounding variables. The study cohort comprised 1867 children (mean age, 10.9 + 2.9 years; 1007 males [53.9%]). Tics were present in 162 children (8.6%), and poor academic performance was noted in 223 (11.9%). Overall poor academic performance was associated with age (OR, 1.71; P < .0001), television viewing (OR, 5.33; P = .04), attention deficit hyperactivity disorder (OR, 1.38; P < .0001), and family history of school dysfunction (OR, 2.43; P = .02) and was negatively associated with higher IQ score (OR, 0.90; P < .0001) and tic disorders (OR, 0.29; P = .01). After adjusting for other covariates, the presence of tic disorders was not associated with poor academic performance in our cohort. Early academic support and modification of environmental characteristics are needed for children at higher risk for school dysfunction, to enhance academic performance.

The successful development of a lactobionic acid (LBA) bioconversion process on an industrial scale demands the selection of appropriate downstream methodological approaches to achieve product purification once the bioconversion of LBA is completed. These approaches depend on the nature of the substrate available for LBA production, and their necessary implementation could constitute a drawback when compared to the lesser effort required in downstream approaches in the production of LBA obtained by chemical synthesis from refined lactose. Thus, the aim of this research is to separate LBA from an acid whey substrate after bioconversion with Pseudomonas taetrolens. Freeze drying, crystallization, adsorption with activated carbon, microfiltration, centrifugation, and precipitation with 96% (v/v) ethanol were carried out to separate and purify LBA. The closest product to commercial LBA was obtained using precipitation with ethanol, obtaining a white powder with 95 ± 2% LBA concentration. The procedure described in this paper could help to produce LBA on an industrial scale via microbial bioconversion from acid whey, developing a promising biotechnological approach for lactose conversion.

Proteins, such as those in blood from slaughterhouses, are a good option for developing edible films. However, films made exclusively from proteins have low strength and high water solubility, which makes them difficult to use in the food industry. The use of cellulosic material, such as nanofibrillated cellulose (NFC), can improve the properties of these films. In the present work, bovine plasma was acidified and treated with ethanol to precipitate its proteins, and these proteins were used to prepare films reinforced with several concentrations of NFC. In addition, control films prepared with untreated bovine plasma and reinforced with NFC were prepared as well. These new edible films were characterized according to their mechanical properties, water vapor permeability, light transmittance, and microstructure. Furthermore, the film with the best properties was selected to be additivated with nisin to test its antimicrobial properties by wrapping meat previously contaminated with Staphylococcus aureus. In this sense, films prepared with the extracted proteins showed better properties than the films prepared with untreated plasma. In addition, the results showed that the reinforcement of the films with a 10% (w/w) of NFC decreased their water solubility and improved their puncture strength and water vapor barrier properties. Finally, the addition of nisin to the films prepared with extracted protein from bovine plasma and NFC gave them antimicrobial properties against S. aureus.

Synbiotic products are a type of functional food with great potential due to consumer interest in foods that improve health and/or reduce the risk of certain diseases. In this study, synbiotic macrocapsules were developed using Lactobacillus paracasei CBA L74 as probiotic and lactobionic acid (LBA) as prebiotic. Firstly, the probiotic was proven to be able to use LBA as the only substrate source checking their growth and lactic acid production. Then, four different types of capsules were produced using sodium alginate as matrix and different hardener solutions (CaCl₂ and chitosan). The macrocapsules were characterised regarding their strength, and the best performing ones were used for further analysis. In order to obtain a synbiotic capsule characterized by a longer stability time due to low water activity, the capsules were dried using freeze and thermal drying. Successively, to revitalize the microorganisms, the capsules were rehydrated in two different media (saline solution and yogurt), subjected to simulated in vitro digestion tests and visually characterised. In addition, their viability over time was assessed. As a result, L. paracasei was able to grow using LBA as the only source of carbon with better production of lactic acid for prolonged periods. The more resistant freeze- and thermal-dried capsules showed differences in rehydration kinetics, and visual changes were also observed. In simulated in vitro digestion tests, capsules rehydrated in yogurt showed the best results in terms of survival. Regarding their viability over time, the importance of the use of chitosan was noted.