RESUMO
Eugenol-lean fraction (98 % lower eugenol content than eugenol-rich fraction) having appreciable phytochemical properties was selectively isolated from clove buds (Syzygium aromaticum Linn) using supercritical carbon dioxide extraction at 40 °C and pressure of 25 MPa with static and dynamic time of 120 and 30 min respectively using ground clove powder which was previously subjected to steam distillation. The extract was used as a flavor ingredient (replacing mustard in classical formulation) and also as a source of natural antioxidant in formulating a new mayonnaise product to improve its nutraceutical value and shelf-life. This product was found to be comparable to the mustard formulated sample (experimental control) organoleptically. The sample did not have typical pungency of clove and had improved physical properties such as increased color tonality with higher chroma values, lower thermal and non-thermal creaming, homogenous and compact microstructure and higher consistency index vis-à-vis the control and standard market samples, even at the end of the storage period of 6 months. Mayonnaise formulated with eugenol-lean clove extract had significantly higher antioxidant activity (IC50 = 10.85 mg/mL), phenolic content (1.89 mg gallic acid equivalent/g mayonnaise) and reducing power (11.29 mg BHT equivalent/g mayonnaise) than mustard-formulated mayonnaise and the market sample. While, the antioxidant activity and phytochemical properties tend to decrease after 30 days for the reference market sample and after 90 days for the experimental control sample, the mayonnaise formulated with eugenol-lean clove extract was found to be stable beyond 6 months.
RESUMO
Microencapsulation of antioxidant-rich fraction obtained by supercritical carbon dioxide extraction (at 50°C, 500 bar with extraction time of 90 min, and flow rate of CO2 at 2 L/min) of lyophilized biomass of Phormidium valderianum was carried out in a spray dryer using maltodextrin and gum arabic. Microencapsulation conditions that provided the best combination of phytochemical properties such as antioxidant activity, phenolic content, and reducing power with reasonable powder yield were an inlet temperature of 130°C and wall material composition as maltodextrin: gum arabic = 70 : 30. Toxicological study reported that the Anatoxin-a content of this encapsulated powder was below the limit of detection of HPLC. Storage study established that encapsulation of this antioxidant-rich algal extract resulted in eight times enhancement of half-life (T 1/2) values. The release profile of microencapsulated antioxidant-rich fraction from the encapsulated powder was found to follow first order anomalous transport kinetics. Therefore, this microencapsulated algal extract with minimum toxicity is a source of natural antioxidant and could have promising use as novel dietary supplement.