Microencapsulation of shiitake (Lentinula edodes ) essential oil by complex coacervation: formation, rheological property, oxidative stability and odour attenuation effect

Microencapsulation of Juniper and Black Pepper Essential Oil Using the Coacervation Method and Its Properties after Freeze-Drying

Essential oils are mixtures of chemical compounds that are very susceptible to the effects of the external environment. Hence, more attention has been drawn to their preservation methods. The aim of the study was to test the possibility of using the classical model of complex coacervation for the microencapsulation of essential oils. Black pepper (Piper nigrum) and juniper (Juniperus communis) essential oils were dissolved in grape seed (GSO) and soybean (SBO) oil to minimize their loss during the process, and formed the core material. Various mixing ratios of polymers (gelatin (G), gum Arabic (GA)) were tested: 1:1; 1:2, and 2:1. The oil content was 10%, and the essential oil content was 1%. The prepared coacervates were lyophilized and then screened to obtain a powder. The following analyses were determined: encapsulation efficiency (EE), Carr index (CI), Hausner ratio (HR), solubility, hygroscopicity, moisture content, and particle size. The highest encapsulation efficiency achieved was within the range of 64.09-59.89%. The mixing ratio G/GA = 2:1 allowed us to obtain powders that were characterized by the lowest solubility (6.55-11.20%). The smallest particle sizes, which did not exceed 6 μm, characterized the powders obtained by mixing G/GA = 1:1. All powder samples were characterized by high cohesiveness and thus poor or very poor flow (CI = 30.58-50.27, HR = 1.45-2.01).

Physical and oxidative stability of astaxanthin microcapsules prepared with liposomes

BACKGROUND

Oil bodies (OBs) are a kind of natural and stable oil nucleate microcapsule in which the triglyceride matrix can be used as an appropriate carrier of hydrophobic molecules. Astaxanthin has high antioxidant properties but is extremely sensitive to oxidation, causing the loss of its bioactive properties.

RESULTS

The purpose of this study was to clarify the effects of environmental factors (light, oxygen, temperature, and pH) on the physical and oxidative stability of astaxanthin microcapsules prepared with peanut oil bodies (POBs). After 14 days of storage, the retention rate of astaxanthin in peanut oil microcapsules (POMs) was significantly increased. The astaxanthin retention rate of POMs stored under light conditions was higher than under dark conditions. Similarly, the retention rate of astaxanthin in POMs was significantly increased during vacuum storage. The astaxanthin retention rate was also the highest when POMs were stored at 4 °C, whereas it was the lowest at pH 3.0.

CONCLUSION

The experiment demonstrated that microcapsulation could improve the astaxanthin retention rate and storage stability, and recombinant OBs were potential ideal wall materials for astaxanthin embedding. © 2022 Society of Chemical Industry.

Encapsulation of volatile compounds in liquid media: Fragrances, flavors, and essential oils in commercial formulations

The first marketed example of the application of microcapsules dates back to 1957. Since then, microencapsulation techniques and knowledge have progressed in a plethora of technological fields, and efforts have been directed toward the design of progressively more efficient carriers. The protection of payloads from the exposure to unfavorable environments indeed grants enhanced efficacy, safety, and stability of encapsulated species while allowing for a fine tuning of their release profile and longer lasting beneficial effects. Perfumes or, more generally, active-loaded microcapsules are nowadays present in a very large number of consumer products. Commercial products currently make use of rigid, stable polymer-based microcapsules with excellent release properties. However, this type of microcapsules does not meet certain sustainability requirements such as biocompatibility and biodegradability: the leaking via wastewater contributes to the alarming phenomenon of microplastic pollution with about 4% of total microplastic in the environment. Therefore, there is a need to address new issues which have been emerging in relation to the poor environmental profile of such materials. The progresses in some of the main application fields of microencapsulation, such as household care, toiletries, cosmetics, food, and pesticides are reviewed herein. The main technologies employed in microcapsules production and the mechanisms underlying the release of actives are also discussed. Both the advantages and disadvantages of every technique have been considered to allow a careful choice of the most suitable technique for a specific target application and prepare the ground for novel ideas and approaches for encapsulation strategies that we expect to be proposed within the next years.

Protection of agarwood essential oil aroma by nanocellulose-graft-polylactic acid

Essential oil products are often volatile, and their aromas cannot be effectively preserved over long periods of time. In this study, nanocellulose crystals were modified, and an amphiphilic copolymer was prepared by ring-opening polymerisation to produce wall materials. A nanocellulose crystal-grafted polylactic acid copolymer was successfully synthesised and characterised using nuclear magnetic resonance spectrometry, Fourier transform infrared spectrometry, X-ray diffraction, and thermogravimetric analysis. Because of the amphiphilic properties of the synthesised copolymer, an agarwood essential oil nanoemulsion system was prepared. Using transmission electron microscopy and dynamic laser light scattering, the nanoemulsion was observed to have an apparent shell-core structure. The nanoemulsion was uniformly distributed, and the system had good stability. Finally, the electronic nose results showed that the nanocellulose crystal-grafted polylactic acid copolymer micelle effectively protected agarwood essential oil aromas.

Study on Preservation of Chilled Beef with Natural Essential Oil Nanocapsules

Beef is rich in amino acids and vitamin B6, carnitine, potassium, protein, and other nutrients. It can improve the body’s ability to resist disease and is especially suitable for growth, development, and postoperation and postrehabilitation care. Under such circumstances, the demand for beef consumption in various countries continues to grow steadily. At present, domestic beef prices continue to rise, and beef supply is insufficient. In addition, fresh beef is easy to be infected with microorganisms in the process of cold storage, which makes fresh beef deteriorated. Therefore, it is very important to add preservatives to prolong the shelf life of chilled beef. In this paper, the preservation of chilled beef with nanocapsules made of natural essential oil from plant extracts was studied. In this study, cumin, Zanthoxylum, ginger, cinnamon, clove, and thyme were selected to study the effect of six kinds of essential oils on beef preservation through comparative experiments. On the basis of such research data, the six kinds of essential oils were compounded, respectively, and different nanoessential oil capsules were applied to the fresh-keeping of chilled beef to make different kinds of nanoessential oil capsules. Through the experiment, the compound essential oil with better preservation effect was obtained. And through the comparison, cinnamon essential oil has obvious antibacterial activity, while ginger essential oil has the worst antibacterial effect. The pH value of beef can be changed and the degradation rate of protein in beef will be slowed down by applying appropriate amount of decomposed plant essential oil to beef samples. Through the above experimental results, we applied the compound essential oil to the preservation of cold and fresh beef at nanometer level and found that the effect was significant, which was worthy of application in major beef products processing plants.