Complex coacervation in gelatin/sodium caseinate mixtures

Effects of γ-polyglutamic acid on the rheological, microstructural and sensory properties of low-fat yogurt

BACKGROUND

While low-fat yogurt offers numerous health benefits, its texture and sensory qualities are poor. This study aimed to investigate the effects of γ-polyglutamic acid (γ-PGA) on the rheological, microstructural and sensory properties of low-fat yogurt using rheological tests, scanning electron microscopy (SEM) and sensory evaluation.

RESULTS

The results showed that the syneresis of low-fat yogurt added with 0.15% γ-PGA was significantly (P < 0.05) reduced to 23.03%, compared to that of low-fat yogurt without γ-PGA (42.87%). An improvement in storage and loss moduli (G', G") and apparent viscosity was also observed. The power law model fitted to rheological data indicated that γ-PGA enhanced the viscoelasticity and strength of the gel network though interaction with casein gel, which might lead to changes in the moduli of yogurts. Microstructural observation via SEM confirmed the enhanced crosslinking between casein micelles and the filling effect of γ-PGA. Sensory liking scores were strongly correlated with rheological properties and apparent viscosity. The results of principal component analysis (PCA) confirmed the positive effects of γ-PGA on quality and rheological attributes of low-fat yogurt.

CONCLUSION

The results of this study provided valuable references for the potential use of γ-PGA as a fat replacer to stabilize the sensory quality of low-fat yogurt. © 2024 Society of Chemical Industry.

Viscoelastic and flow behaviour of β-lactoglobulin/lactoferrin coacervates: Influence of temperature and ionic strength

Heteroprotein complex coacervation has potential for a wide range of applications. However, the sensitivity of coacervates to slight changes in physico-chemical conditions may constitute a technological barrier for their development and deserves to be better understood. In this study, the rheological properties of β-lactoglobulin/lactoferrin (βLG/LF) heteroprotein complex coacervates were investigated with respect to narrow changes of temperature (5-40 °C) and ionic strength (0 to 10 mM added NaCl). The apparent viscosity of βLG/LF coacervates prepared at 20 °C showed a high sensitivity to temperature, decreasing progressively at elevated temperatures. Frequency sweep experiments demonstrated that coacervates behave as a viscoelastic liquid throughout the investigated frequency range at T>10°C. Time-temperature superposition principle revealed that the interaction involved in the coacervation process were temperature-independent. The calculated activation energy was approximately 85 kJ/mol. The addition of NaCl (up to 10mM) prior to coacervation, resulted in an increase of the viscosity but did not show a clear trend in the evolution of viscoelastic moduli. These new insights allow a better understanding of the interactions involved in concentrated protein coacervates enabling better control over their potential uses.

Microencapsulation of vitamins: A review and meta-analysis of coating materials, release and food fortification

Vitamins are responsible for providing biological properties to the human body; however, their instability under certain environmental conditions limits their utilization in the food industry. The objective was to conduct a systematic review on the use of biopolymers and lipid bases in microencapsulation processes, assessing their impact on the stability, controlled release, and viability of fortified foods with microencapsulated vitamins. The literature search was conducted between the years 2013-2023, gathering information from databases such as Scopus, PubMed, Web of Science and publishers including Taylor & Francis, Elsevier, Springer and MDPI; a total of 49 articles were compiled The results were classified according to the microencapsulation method, considering the following information: core, coating material, solvent, formulation, process conditions, particle size, efficiency, yield, bioavailability, bioaccessibility, in vitro release, correlation coefficient and references. It has been evidenced that gums are the most frequently employed coatings in the protection of vitamins (14.04%), followed by alginate (10.53%), modified chitosan (9.65%), whey protein (8.77%), lipid bases (8.77%), chitosan (7.89%), modified starch (7.89%), starch (7.02%), gelatin (6.14%), maltodextrin (5.26%), zein (3.51%), pectin (2.63%) and other materials (7.89%). The factors influencing the release of vitamins include pH, modification of the coating material and crosslinking agents; additionally, it was determined that the most fitting mathematical model for release values is Weibull, followed by Zero Order, Higuchi and Korsmeyer-Peppas; finally, foods commonly fortified with microencapsulated vitamins were described, with yogurt, bakery products and gummy candies being notable examples.

Preparation and characterization of vitamin A microcapsules nutrient fortified salt

Vitamin A, also known as retinol, is a fat-soluble vitamin that plays crucial role in various physiological functions In vivo. However, factors such as light, oxygen, and others may impact the stability of VA. To enhance its stability. This study microencapsulated VA, Gelatin, carboxymethyl cellulose, and salt were mixed in a ratio of 5:1:0.1 as the shell material. Additionally, 12% TG and 3.5% sucrose ester were added with core-shell ratio of 1:8. The experimental results indicated that VA microcapsules exhibited an encapsulation efficiency of 81.12%, after 9 weeks of storage this rate decreased to 75.38%, and the encapsulated VA oil did not exhibit extravasation. The addition of an appropriate amount of salt to the shell material enhanced the mechanical properties of the shell material, compared to the shell material without added salt, the leakage of VA in the salt-added sample decreased by 5.8% for 30 min and 14.5% for 60 min. In vitro release experiments showed that after 3 h of incubation in simulated gastric fluid, the microcapsules had an 18.52% release rate. In simulated intestinal fluid, this increased to 66.58%, indicating strong enteric solubility.

Supplementary Information

The online version contains supplementary material available at 10.1007/s13197-024-05962-w.

Advances in protein-based microcapsules and their applications: A review

Due to their excellent emulsification, biocompatibility, and biological activity, proteins are widely used as microcapsule wall materials for encapsulating drugs, natural bioactive substances, essential oils, probiotics, etc. In this review, we summarize the protein-based microcapsules, discussing the types of proteins utilized in microcapsule wall materials, the preparation process, and the main factors that influence their properties. Additionally, we conclude with examples of the vital role of protein-based microcapsules in advancing the food industry from primary processing to deep processing and their potential applications in the biomedical, chemical, and textile industries. However, the low stability and controllability of protein wall materials lead to degraded performance and quality of microcapsules. Protein complexes with polysaccharides or modifications to proteins are often used to improve the thermal instability, pH sensitivity, encapsulation efficiency and antioxidant capacity of microcapsules. In addition, factors such as wall material composition, wall material ratio, the ratio of core to wall material, pH, and preparation method all play critical roles in the preparation and performance of microcapsules. The application area and scope of protein-based microcapsules can be further expanded by optimizing the preparation process and studying the microcapsule release mechanism and control strategy.

Investigation on 3D Printing of Shrimp Surimi Adding Three Edible Oils

Three-dimensional (3D) printing provides a new method for innovative processing of shrimp surimi. However, there still exists a problem of uneven discharge during the 3D printing of surimi. The effects of different amounts of lard oil (LO), soybean oil (SO), and olive oil (OO) (0%, 2%, 4%, and 6%, respectively) added to shrimp surimi on the 3D printability of surimi were evaluated. The findings showed that with the increase in the added oil, the rheological properties, texture properties, water-holding capacity (WHC), and water distribution of surimi with the same kind of oil were significantly improved; the printing accuracy first increased and then decreased; and the printing stability showed an increasing trend (p < 0.05). The surimi with 4% oil had the highest printing adaptability (accuracy and stability). Different kinds of oil have different degrees of impact on the physical properties of surimi, thereby improving 3D-printing adaptability. Among all kinds of oil, LO had the best printing adaptability. In addition, according to various indicators and principal component analysis, adding 4% LO to shrimp surimi gave the best 3D-printing adaptability. But from the aspects of 3D printing properties and nutrition, adding 4% SO was more in line with the nutritional needs of contemporary people.

Effect of poly-γ-glutamic acid on the stability of set yoghurts

The effects of poly-γ-glutamic acid (γ-PGA) on the stability of yogurt were studied in terms of texture, rheology, particle size, and microstructure. The effects of γ-PGA on the pH and water holding capacity (WHC) of yogurt during refrigeration were also studied. The tan δ value of the yogurt with 0.04% (w/w) γ-PGA was significantly lower than that of control. The addition of γ-PGA decreased the particle size. The yogurt with 0.02% (w/w) γ-PGA had denser network structure with less porosity, and cross-linking between complexes occurred with greater frequency. The pH of the yogurt supplemented with 0.02% and 0.04% γ-PGA was significantly higher. WHC increased with the amount of γ-PGA. The addition of γ-PGA to yogurt strengthened the antishear ability, inhibited the postacidification phenomenon, and improved stability during refrigeration.

Facile fabrication of tea tree oil-loaded antibacterial microcapsules by complex coacervation of sodium alginate/quaternary ammonium salt of chitosan

In this study, flavoured tea tree oil (TTO)-loaded antibacterial microcapsules were developed based on the complex coacervation of sodium alginate (SA) and a quaternary ammonium salt of chitosan (HACC).

The effect of fibers on coagulation of casein-based enteral nutrition in an artificial gastric digestion model

A serious complication seen in critically ill patients is the solidification of enteral nutrition causing gastrointestinal obstruction.