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Increasing the shelf-life of sensitive substances and targeting the release of nutritional/bioactive molecules are among the great challenges for the food industry. The development of food products with embedded encapsulation devices used to reach these objectives, constitutes a growing market. Milk proteins are biopolymers that are chemically and structurally versatile and are well adapted to several encapsulation purposes. Therefore, in this paper, the strategies, techniques, advantages and trends associated with the use of milk proteins as encapsulating device are reviewed. Special attention is given to the novel potential of reversibly co-assembled protein structures as encapsulating devices.

a b s t r a c tThis study reports the effect of different concentrations of nisin (0, 100 and 500 IU mL À1 ) against Staphylococcus aureus in Minas Traditional Serro cheese manufactured with raw milk. We also evaluated the influence of nisin on the physicochemical properties, mechanical characteristics and colour of the cheese over 60 days of ripening. Nisin was effective in reducing S. aureus count in Serro cheese; a reduction of 1.2 and 2.0 log cycles in S. aureus count was observed from the 7th day of ripening for cheese containing 100 IU mL À1 and 500 IU mL À1 of nisin, respectively, compared with the control sample. The major changes in physicochemical properties, mechanical characteristics and colour were associated with cheese ripening, except for the index of ripening, which was lower in the presence of nisin. The addition of nisin is a powerful tool to contribute to the safety of traditional cheese produced with raw milk.

a b s t r a c tThis study evaluated the effect of addition of modified starch on the characteristics of dulce de leche, being conducted in two phases. In the initial phase, starches were evaluated for their ability to provide viscosity in model solutions representing the composition of dulce de leche during processing, thus evaluating the effect of solid concentration, which occurs during production, on the ability of starches to increase viscosity in simulated conditions of heat treatment and agitation promoted by Rapid Visco Analyser (RVA). It has been chosen 2 starches and 2 concentrations of soluble solids from the results of the initial phase, being employed as a criterion of choice starches with the highest viscosities at each solid concentration processing phase. In the second stage, 6 treatments were applied in triplicate, in which it's been determined the chemical composition, the instrumental color, texture profile and yield. Analyses were performed on crystallization of lactose during storage. According to the established conditions of the experiment, the starch configures itself as an important optional ingredient for the production of dulce de leche providing then longer shelf life without change in texture, composition, yield and sensory characteristic.

Casein micelles are porous colloidal particles, constituted of casein molecules, water, and minerals. The vulnerability of the supramolecular structure of casein micelles face to changes in the environmental conditions restrains their applications in other domains besides food. Thus, redesigning casein micelles is a challenge to create new functionalities for these biosourced particles. The objective of this work was to create stable casein microgels from casein micelles using a natural cross-linker, named genipin. Suspensions of purified casein micelles (25 g L(-1)) were mixed with genipin solutions to have final concentrations of 5, 10, and 20 mM genipin. Covalently linked casein microgels were formed via cross-linking of lysyl and arginyl residues of casein molecules. The reacted products exhibited blue color. The cross-linking reaction induced gradual changes on the colloidal properties of the particles. The casein microgels were smaller and more negatively charged and presented smoother surfaces than casein micelles. These results were explained based on the cross-linking of free NH2 present in an external layer of κ-casein. Light scattering and rheological measurements showed that the reaction between genipin and casein molecules was intramicellar, as one single population of particles was observed and the values of viscosity (and, consequently, the volume fraction of the particles) were reduced. Contrary to the casein micelles, the casein microgels were resistant to the presence of dissociating agents, e.g., citrate (calcium chelating) and urea, but swelled as a consequence of internal electrostatic repulsion and the disruption of hydrophobic interactions between protein chains. The casein microgels did not dissociate at the air-solution interface and formed solid-like interfaces rather than a viscoelastic gel. The potential use of casein microgels as adaptable nanocarriers is proposed in the article.

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FT-Raman spectroscopy has been explored as a quick screening method to evaluate the presence of lactose and identify milk powder samples adulterated with maltodextrin (2.5-50% w/w). Raman measurements can easily differentiate samples of milk powder, without the need for sample preparation, while traditional quality control methods, including high performance liquid chromatography, are cumbersome and slow. FT-Raman spectra were obtained from samples of whole lactose and low-lactose milk powder, both without and with addition of maltodextrin. Differences were observed between the spectra involved in identifying samples with low lactose content, as well as adulterated samples. Exploratory data analysis using Raman spectroscopy and multivariate analysis was also developed to classify samples with PCA and PLS-DA. The PLS-DA models obtained allowed to correctly classify all samples. These results demonstrate the utility of FT-Raman spectroscopy in combination with chemometrics to infer about the quality of milk powder.