Effective stabilization of CLA by microencapsulation in pea protein

Maltodextrin and Gum Arabic-Based Microencapsulation Methods for Anthocyanin Preservation in Juçara Palm (Euterpe edulis Martius) Fruit Pulp

The juçara fruits (Euterpe edulis Martius), native to the Atlantic Forest, are rich in anthocyanins. To preserve the anthocyanins in juçara fruit pulp, this study aimed to evaluate the effectiveness of microencapsulation by spray drying and freeze drying with maltodextrin (dextrose equivalent 16.5 to 19.5) and gum arabic in different proportions. The obtained microparticles were characterized by quantifying the total polyphenol and anthocyanin contents, by performing differential scanning calorimetry, thermogravimetry, and infrared spectroscopy and by using scanning electron microscopy to analyze the morphology of the particles. The total amount of polyphenols in the fruit pulp was 750 ± 16.7 mg GAE/100 g of the freeze-dried sample. The total anthocyanins in the fruit pulp was 181.25 ± 5.36 (mg/100 g). The microparticles were formed by employing maltodextrin and gum arabic in a 1:1 proportion as the polymeric matrix; the mixtures of pulp and polymeric matrix were prepared in proportions of 2:3 and 2:1, preserving up to 83.69% of the anthocyanin content. Lyophilization of the 2:1 mixture resulted in an anthocyanin content of 116.89 ± 4.43 (mg/100 g), whereas lyophilization of the 2:3 mixture resulted in 151.68 ± 1.39 (mg/100 g) anthocyanin content, which did not differ from the value obtained by spray drying the 2:3 mixture (150.76 ± 5.79 (mg/100 g)). Thermal analyses showed that the microparticles obtained by freeze drying at a ratio of 2:3 presented greater resistance to degradation with increasing temperature. The incorporation of the pulp in the polymeric matrix was demonstrated by IR analyses. Microparticles obtained by freeze drying showed the formation of various-sized flakes, whereas those obtained by spray drying were spherical in shape. Microencapsulation is a possible alternative for improving the stability of the anthocyanins in this fruit.

Nanostructuring Biopolymers for Improved Food Quality and Safety

Food-grade biopolymers, apart from their inherent nutritional properties, can be tailored designed for improving food quality and safety, either serving as delivery vehicles for bioactive molecules, or as novel packaging components, not only improving the transport properties of biobased packaging structures, but also imparting active antibacterial and antiviral properties. In this chapter, the potential of different food-grade biopolymers (mainly proteins and carbohydrates but also some biopolyesters) to serve as encapsulating matrices for the protection of sensitive bioactives or as nanostructured packaging layers to improve transport properties and control the growth of pathogenic bacteria and viruses are described based on some developments carried out by the authors, as well as the most prominent works found in literature in this area.

Effect of the incorporation of Bifidobacterium BB-12 microencapsulated with sweet whey and inulin on the properties of Greek-style yogurt

The effect of the addition of Bifidobacterium BB-12 microencapsulated by spray drying with sweet whey and inulin on the microbiological, physicochemical and texture properties of Greek-style yogurt was evaluated during 28 days of storage. The survival of this probiotic under simulated gastrointestinal conditions was assessed after this storage time. Three formulations of Greek-style yogurt were produced: Control (with free cells); SW (with microcapsules produced only with sweet whey); and SWI (with microcapsules produced with sweet whey and inulin). The counts of Bifidobacterium BB-12 remained stable during storage in the Control yogurt and in the SW yogurt, while a slight decrease occurred in the SWI yogurt. Nevertheless, the addition of microcapsules improved the survival of S. thermophilus and L. bulgaricus in the SW yogurt after 14 days of storage. In general, incorporation of microcapsules into Greek-style yogurt affected specific physicochemical and textural properties of the samples. A decrease in the probiotic survival rate during gastrointestinal simulation was observed for all samples; however, it was more pronounced in the SWI yogurt. Even though the protective effect of the microcapsules was not evident, the results showed that Greek-style yogurt is a promising carrier for incorporation of Bifidobacterium BB-12.

Improving functional properties of pea protein isolate for microencapsulation of flaxseed oil

Unhydrolysed pea protein (UN) forms very viscous emulsions when used at higher concentrations. To overcome this, UN was hydrolysed using enzymes alcalase, flavourzyme, neutrase, alcalase-flavourzyme, and neutrase-flavourzyme at 50 °C for 0 min, 30 min, 60 min, and 120 min to form hydrolysed proteins A, F, N, AF, and NF, respectively. All hydrolysed proteins had lower apparent viscosity and higher solubility than UN. Foaming capacity of A was the highest, followed by NF, N, and AF. Hydrolysed proteins N60, A60, NF60, and AF60 were prepared by hydrolysing UN for 60 min and used further for microencapsulation. At 20% oil loading (on a total solid basis), the encapsulated powder N60 had the highest microencapsulation efficiency (ME = 56.2). A decrease in ME occurred as oil loading increased to 40%. To improve the ME of N60, >90%, UN and maltodextrin were added. Flowability and particle size distribution of microencapsulated powders with >90% microencapsulation efficiency and morphology of all powders were investigated. This study identified a new way to improve pea protein functionality in emulsions, as well as a new application of hydrolysed pea protein as wall material for microencapsulation.

Stability of Trans-Resveratrol Encapsulated in a Protein Matrix Produced Using Spray Drying to UV Light Stress and Simulated Gastro-Intestinal Digestion

Trans-resveratrol has demonstrated the potential to provide both therapeutic and preventive activities against chronic diseases such as heart disease and cancer. The incorporation of trans-resveratrol into food products would allow for broader access of this bioactive compound to a larger population. However, this strategy is limited by instability of trans-resveratrol under environmental conditions and within the digestive system leading to isomerization of trans-resveratrol (bioactive form) to cis-resveratrol (bio-inactive form). Studies in the stabilization of trans-resveratrol into protein microparticles are presented. Trans-resveratrol was encapsulated using whey protein concentrate (WPC) or sodium caseinate (SC), with or without anhydrous milk fat (AMF). Binding of resveratrol and aromatic residues in protein was estimated utilizing the Stern-Volmer equation and the number of tryptophan residues. The stability of encapsulated resveratrol was evaluated after exposure to ultraviolet A (UVA) light and 3-stage in vitro digestion. After UVA light exposure, SC-based microcapsules maintained a higher trans:cis resveratrol ratio (0.63, P < 0.05) than WPC-based microcapsules (0.43) and unencapsulated resveratrol (0.49). In addition, encapsulation of resveratrol in both protein microparticles led to an increased digestive stability and bioaccessibility in comparison to unencapsulated resveratrol (47% and 23%, respectively, P < 0.05). SC-based microcapsules provided a higher digestive stability and bioaccessibility (86% and 81%; P < 0.05) compared to WPC-based microcapsules (71% and 68%). The addition of AMF to the microcapsules did not significantly change the in vitro digestion values. In conclusion, SC-based microencapsulation increased the stability of trans-resveratrol to UVA light exposure and simulated digestion conditions. This encapsulation-system-approach can be extended to other labile, bioactive polyphenols.