Dipan Chatterjee

Spray Dried Extract of Phormidium valderianum as a Promising Source of Natural Antioxidant

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.

Electronic Nose Setup for Estimation of Rancidity in Cookies

Rancidity is a major problem in food systems which occurs through lipid oxidation and significantly affects quality of foods. Owing to the drawbacks of conventional methods of estimating lipid oxidation in foods, alternative inexpensive technology such as electronic nose (e-nose) technology that can accurately and rapidly determine odor profile of foods, is gaining importance. First section of this chapter presents various applications of e-nose analysis of several food systems. Latter section of this chapter focusses on assessment of shelf-life of cookies formulated with un-encapsulated and encapsulated eugenol-rich clove extracts (obtained by supercritical carbon dioxide extraction from clove buds) as a source of natural antioxidant using ALPHA MOS e-nose system and a customized e-nose system. The e-nose results were further validated by conventional methods of rancidity determination. Shelf-life study for a storage period of 200 days revealed that normal cookies without any antioxidant have shelf-life of 100 days when stored in aluminium laminates at \(23 \pm 2^{\,\circ }\mathrm{C}\), while administration of encapsulated clove extract as antioxidant prevented rancidity in cookies for at least 200 days with a shelf-life lead of 100 days over control cookies. These observations were further affirmed by phytochemical analyses which indicated that the addition of encapsulated clove extract in cookies enhanced its nutraceutical potential and antioxidant activity for at least 200 days. Finally, linear regression equations were developed using which rancidity parameters of conventional biochemical assays of cookies can be directly derived from e-nose sensor responses.