Microencapsulation of ultrasound-assisted phenolic extracts of sugar maple leaves: Characterization, in vitro gastrointestinal digestion, and storage stability.

Sugar maple leaves (SML), usually considered residue plant biomass and discarded accordingly, contain a considerable amount of phenolic antioxidants. In this study, SML phenolics were extracted employing both advanced (homogenization pretreated ultrasound-assisted extraction) and conventional (maceration) methods followed by their encapsulation by freeze drying and spray drying using a combination of maltodextrin and gum arabic as coating agents. Detailed physicochemical analyses revealed that the encapsulated microparticles had high solubility (>90 %) and encapsulation efficiency (>95 %), acceptable thermal stability with good handling properties. Phenolic compounds were completely released from microparticles during simulated gastric conditions. The microparticles influenced the bioaccessibility of more than 43 % of the phenolic fraction in the intestinal phase. The antioxidant capacity of the microparticles was preserved during storage. These findings suggest the effectiveness of the microencapsulation process for producing high quality microparticles of SML phenolic extracts and the possibility of their use in the food, nutraceutical, bio-pharmaceutical sectors.

Correction to: Osmotic and convective hot air drying of sweet gourd.

[This corrects the article DOI: 10.1007/s10068-022-01193-x.].

Osmotic and convective hot air drying of sweet gourd.

Kinetics of osmotic dehydration (OD) and insights into the effect of salt concentration (5%, 10%, 15%, 20%), drying temperature (50 ∘C, 60 ∘C, 70 ∘C), and sample thickness (4 mm, 6 mm, 8 mm) on the drying kinetics of sweet gourd of two varieties (SGV-1 and SGV-2) were investigated based on the Fick's second law of diffusion model. Quality attributes (chemical and organoleptic) of biscuit formulated with osmotic dehydrated sweet gourd powder were assessed. Results showed that, significant changes occurred during the first 2 h of process where mass transfer kinetics were increased with increasing salt concentration. With increasing time, drying rate was proportional to the temperature, inversely proportional to the sample thickness as well as salt concentration. Moreover, sweet gourd variety has shown impact on formulated products quality and consumer acceptability which could serve as a ground to diversify the use of sweet gourd towards industrial application. Supplementary Information: The online version contains supplementary material available at 10.1007/s10068-022-01193-x.

Restructuring plant-derived composites towards the production of meat-analog based coated fried food.

This study utilized different plant-based composites to develop restructured meat-analog (MA). Physicochemical, thermal, mechanical, structural, and sensory properties of formulated MA as well as batter-coated fried MAs were studied, and compared with a commercial product. Protein (23.27-24.68 %), moisture (57.05-58.78 %), pH (7.19-7.57), color (L:64.76-66.84, a:0.62-1.98, b:18.84-20.49), and textural (MF:0.22-0.52 N, GF:0.07-0.24 N/sec, FA:0.74-1.92 N.sec) attributes of formulated MAs were substantially impacted by the ratio of soy-protein-isolate (SPI) and wheat-gluten (WG). Incorporation of higher WG and lower SPI resulted in the formation of chicken-like fibrous and porous structure, hence, increased consumers acceptability of MA-based coated fried products. Microporosity (crust:51.14-58.35 %, core: 63.57-71.55 %), surface opening (5.67-14.75 %), and fractal dimension (2.586-2.402) of coated fried MAs were dependent on the formulation of batter-coating. MA-based coated fried products surface moisture-fat (SMR:0.51-187.20 au; SFR: 2.01-20.17 au) profile significantly (p < 0.05) varied with the formulations of batter-coating. Negative glass-transition-temperature (around -23 °C) is prime concern for MA-based fried products stability at room environment.

Phenolic mapping and associated antioxidant activities through the annual growth cycle of sugar maple leaves.

Concentrations of antioxidant components (analyzed by HPLC-UV) and antioxidant attributes (assayed by radical scavenging and non-radical redox potential methods) of sugar maple leaves (SML) from different harvesting times were investigated. Moreover, measurements of colorimetry, SEM, and FTIR spectroscopy-based characterization of leaves composition, throughout the growth cycle, were performed. Results showed that the antioxidant activities of SML are strongly correlated with phenolic contents and significantly (p < 0.05) varied with harvesting time where minimum amount of total phenolics (105.67 ± 13.16 mg GAE/g DM) and total flavonoids (3.27 ± 0.26 mg CTE/g DM) were found to be concentrated in Fall leaves. The absorption bands obtained from FTIR spectra revealed the presence of functional groups that have great significance towards the antioxidant activity of SML. Principal component analysis revealed that biosynthesis of maximum phenolic compounds in SML mostly occurs during the leaf expansion and growth phases. The obtained data provided a better understanding towards the effect of harvesting time on the phenolic mapping of SML in favor of its valorization into functional food ingredients.

Green extraction and characterization of leaves phenolic compounds: a comprehensive review.

Although containing significant levels of phenolic compounds (PCs), leaves biomass coming from either forest, agriculture, or the processing industry are considered as waste, which upon disposal, brings in environmental issues. As the demand for PCs in functional food, pharmaceutical, nutraceutical and cosmetic sector is escalating day by day, recovering PCs from leaves biomass would solve both the waste disposal problem while ensuring a valuable "societal health" ingredient thus highly contributing to a sustainable food chain from both economic and environmental perspectives. In our search for environmentally benign, efficient, and cost-cutting techniques for the extraction of PCs, green extraction (GE) is presenting itself as the best option in modern industrial processing. This current review aims to highlight the recent progress, constraints, legislative framework, and future directions in GE and characterization of PCs from leaves, concentrating particularly on five plant species (tea, moringa, stevia, sea buckthorn, and pistacia) based on the screened journals that precisely showed improvements in extraction efficiency along with maintaining extract quality. This overview will serve researchers and relevant industries engaged in the development of suitable techniques for the extraction of PCs with increasing yield.