Phase transition issues in the field of foods and drugs have significantly influenced these industries and consequently attracted the attention of scientists and engineers. The study of thermodynamic parameters such as the glass transition temperature (Tg), melting temperature (Tm), crystallization temperature (Tc), enthalpy (H), and heat capacity (Cp) may provide important information that can be used in the development of new products and improvement of those already in the market. The techniques most commonly employed for characterizing phase transitions are thermogravimetric analysis (TGA), dynamic mechanical analysis (DMA), thermomechanical analysis (TMA), and differential scanning calorimetry (DSC). Among these techniques, DSC is preferred because it allows the detection of transitions in a wide range of temperatures (−90 to 550 °C) and ease in the quantitative and qualitative analysis of the transitions. However, the standard DSC still presents some limitations that may reduce the accuracy and precision of measurements. The modulated differential scanning calorimetry (MDSC) has overcome some of these issues by employing sinusoidally modulated heating rates, which are used to determine the heat capacity. Another variant of the MDSC is the supercooling MDSC (SMDSC). SMDSC allows the detection of more complex thermal events such as solid–solid (Ts-s) transitions, liquid–liquid (Tl-l) transitions, and vitrification and devitrification temperatures (Tv and Tdv, respectively), which are typically found at the supercooling temperatures (Tco). The main advantage of MDSC relies on the accurate detection of complex transitions and the possibility of distinguishing reversible events (dependent on the heat capacity) from non-reversible events (dependent on kinetics).

Since its invention in 1872 by Samuel Percy, the spray drying of food products has been widely used, whether in products consumed by babies in milk formulations, powdered sweets and cocoa soluble in milk for children, or food supplements rich in proteins, vitamins, and minerals for adults. All of these products were first formulated in solution and then converted into powders to facilitate the transport and preservation of the properties during storage. In recent years, novel technologies such as nano spray drying have emerged for the development of food formulations with high-cost active ingredients. The aim of the present work is to present a review of the literature reported in the last 10 years related to these technologies. The basis of the spray-drying technologies i.e., conventional and nano, are described and compared, emphasizing the instrumental processing conditions for achieving a desired product. Examples of some unwanted reactions presented during the encapsulation of active ingredients are provided.

Maltodextrin (MX) is an ingredient in high demand in the food industry, mainly for its useful physical properties which depend on the dextrose equivalent (DE). The DE has however been shown to be an inaccurate parameter for predicting the performance of the MXs in technological applications, hence commercial MXs were characterized by mass spectrometry (MS) to determine their molecular weight distribution (MWD) and degree of polymerization (DP). Samples were subjected to different water activities (a_w). Water adsorption was similar at low a_w, but radically increased with the DP at higher a_w. The decomposition temperature (T_d) showed some variations attributed to the thermal hydrolysis induced by the large amount of adsorbed water and the supplied heat. The glass transition temperature (T_g) linearly decreased with both, a_w and DP. The microstructural analysis by X-ray diffraction showed that MXs did not crystallize with the adsorption of water, preserving their amorphous structure. The optical micrographs showed radical changes in the overall appearance of the MXs, indicating a transition from a glassy to a rubbery state. Based on these characterizations, different technological applications for the MXs were suggested.

Oxidation is the main problem in preserving food products during storage. A relatively novel strategy is the use of antioxidant-enriched edible films. Antioxidants hinder reactive oxygen species, which mainly affect fats and proteins in food. At present, these films have been improved by the addition of micro- and nanoliposomes coated with carbohydrate polymers, which are not hazardous for human health and can be ingested without risk. The liposomes are loaded with different antioxidants, and their effects are observed as a longer storage time of the food product. The synergy of these methodologies and advances can lead to the displacement of the protective packaging used currently, which would result in food products with functional properties added by the films, an increase in shelf life, and an improvement to the environment by reducing the amount of waste.