Extraction optimization and microencapsulation of phenolic antioxidant compounds from lemon balm ( Melissa officinalis  L.): Instant soluble tea production

Abstract

The purpose of this study was to extract phenolics from lemon balm followed by microencapsulation with spray drying. The optimum extraction conditions were 100°C for the temperature and 120 min for the time with TPC of 6,365 mg GAE/100 g and ABTS radical scavenging activity of 9,196 mg TEAC/100 g. Lemon balm extracts were spray dried using three different air inlet temperatures (130°C, 165°C, and 200°C) of which 165°C was provided better scores than the other points in terms of microencapsulation yield (65.9%), microencapsulation efficiency (99.4%), dry matter (98.3%), and water activity (0.160). The inlet air temperatures had an insignificant (p > .05) effect on the antioxidant capacity of the microcapsules. Phenolic acids in lemon balm were slightly affected by the extraction and spray drying conditions. However, extraction followed by spray drying resulted in significant loss in the amount of volatiles such as geranial, neral, citronellal, and caryophyllene. Practical applications Hot water extracts of the medicinal and aromatic plants are consumed as herbal tea across the world and their biological activity varies depending on the extraction conditions. Furthermore, bioactive compounds are sensitive to environmental conditions when the compounds dissolved in water. The conditions necessary for the effective extraction of bioactive compounds are specific to the target plant and it is a problem for the consumer. Optimization of extraction conditions of lemon balm phenolics could provide useful information for the consumer and food industry. The production of phenolic microcapsules (instant soluble tea) from lemon balm could facilitate herbal tea preparation and reduce the preparation time.

Phenolic Content, Main Flavonoids, and Antioxidant Capacity of Instant Sweet Tea (Lithocarpus litseifolius [Hance] Chun) Prepared with Different Raw Materials and Drying Methods

“…Although extraction condition studies have been reported by many researchers, the evaluation of the instant tea powders of Lithocarpus litseifolius [Hance] Chun is very limited. In our study, the yield of the instant sweet tea powder increased with the extraction temperature from 55 to 85 • C, and this result was similar to other studies [14,24], suggesting that a higher yield of instant tea powder might be associated with a higher phenolic content. As the temperature increases, the plant tissue softens and the viscosity and surface tension of water decrease, resulting in the dissolution of more phenolic compounds [25].…”

“…However, other researchers found that instant black teas prepared by fermented dhools showed higher polyphenolic and theaflavin contents, as well as antioxidant activities than those prepared by black tea and BMF [8]. In addition, the extraction/brew conditions (e.g., extraction temperature and time, brewing time, and water volume) were found to significantly influence the total soluble solid, phenolic content, and antioxidant activity of instant teas [10][11][12][13][14].…”

Six Common Herbs with Distinctive Bioactive, Antioxidant Components. A Review of Their Separation Techniques

“…Optimization of the water extraction conditions resulted in 100 °C for 120 min as the optimum conditions for TPC recovery and antiradical (DPPH, ABTS + ) activity of the extracts [ 138 ]. Hydrolysis with 0.2 M hydrochloric acid increased the TPC content of the extract, and the FRAP, indicating that glycosylated forms might have been hydrolyzed to the respective aglycons that present higher antioxidant power.…”

“…Additionally, they proved effective antioxidants for lipid protection in oils and emulsions [ 112 ]. Water extracts, rich in phenolic compounds were effectively encapsulated in maltodextrin, by spray drying [ 138 ]. However, there is a need for further study towards the purification and formulation of these extracts in order to be exploited commercially.…”

Modeling of sunflower oil treated with lemon balm ( Melissa officinalis ): Artificial neural networks versus multiple linear regression

“…In this study, sunflower oil has been selected as the case model, since it is the most used oil in European countries for frying foods and margarine production as well as salad dressing (Yanishlieva & Marinova, 2001). On the other hand, lemon balm ( Melissa officinalis ) has been reported to have antioxidant properties due to its phenolic substances (Dastmalchi et al, 2008; Kamdem et al, 2013; Miron et al, 2013; Tülek et al, 2021). Therefore, it was used as an natural antioxidant to increase the oil's resistance to oxidation.…”