Essential oils are produced as secondary metabolites of aromatic plants and can be extracted from leaves, seeds or fruit peel of the plants. Citrus peel is a rich source of limonene which is antimicrobial in nature. The present study aimed to deal with the physicochemical, antioxidant and antimicrobial properties of citrus peel essential oil from Citrus reticulate (mandarin orange), Citrus limetta (mosambi) and Citrus limon (lemon).  The lemon peel oil had lower peroxide value (1.6 meq/kg of sample), saponification value (112.2 mg KOH/g of oil) and higher iodine value (116 gI2/100g oil) when compared with orange and mosambi peel essential oil. DPPH (2,2-diphenyl-1-picrylhydrazyl) free radical scavenging activity of citrus peel essential oil was measured  and the result indicated that the total antioxidant activity of lemon peel oil was 89.2 % Radical Scavenging activity (RSA). The antifungal activity was assessed by agar dilution method, whereas the antibacterial property was assessed by the agar diffusion method. Lemon peel oil recorded better antimicrobial properties with minimum inhibitory concentration of 0.3% against Aspergillus flavus MTCC 277, 0.2% for Penicillium  MTCC 1995 and Fusarium oxysporum MTCC 284. Likewise, the minimum inhibitory concentration of lemon peel oil against Staphylococcus aureus MTCC 96 was 0.3%; Salmonella enterica MTCC 733 and Erwinia sp MTCC 2760 was 0.5%; Pseudomonas aeruginosa MTCC 1688 and Escherichia coli MTCC 443 was 0.7%. This comparative study showed that lemon peel oil had better physicochemical and antioxidant property. Lemon peel oil can be used as a preservative in the food system as it exhibited antibacterial and antifungal activity.

There is a demand for Palmyra palm (Borassus flabellifer) tender endosperm (Taal; Nungu) in the off season due to its health benefits. To extend the shelf life of Palmyra palm Tender Fruit Endosperm (PTFE) it was thermally processed. The versatile retort processing technology was used to increase the shelf life. Processed tender endosperm packed in transparent retort pouches (TRP) and nontransparent retort pouches (NTRP) were evaluated for textural, color, microbial, and sensorial properties. Heat penetration tests and F- values were also determined. Processed tender endosperm was compared with fresh endosperm and there was a shelf life of 6 months under ambient storage conditions (30-32°C). The process time to reach lethality in nontransparent pouches (14.03 min) was higher than that in transparent pouches (13.02 min) and the difference may be due to the layer addition of packaging material. Textural profile analysis revealed that hardness, gumminess, and chewiness decreased when the processing and storage time was increased. The sensory score obtained similar results to the textural analysis (Hardness value of TRP:5.063kgfand NTRP: 4.58kgf); succulence and toughness decreased over the prolonged processing time. The tender endosperm in metalized retort pouches scored higher (7.9 as overall acceptability) than that in transparent retort pouches (7.8 as overall acceptability) in terms of sensory analysis. Retorted pouches were microbiologically safe until 6 months with the absence of Clostridium, Staphylococcus and Salmonella spp.The present experiment on shelf life extension of Palmyra tender endosperm (Nungu) helps in preserving the perishable healthy delicacy for more months and also enables to fetch higher income for the farmers with minimal investment.