HARNESSING TROPICAL BROWN SEAWEED TO DERIVE NUTRITIONAL AND FUNCTIONAL SEAWEED BASED PRODUCTS

ABSTRACT Title : Harnessing tropical brown seaweed to derive nutritional and functional seaweed based products. Name of the student : K.Vijay Degree : M.F. Sc. Chairman : Dr.S. Balasundari Department : Fish processing Technology School : School of Harvest and Post harvest Technology College : Fisheries College and Research Institute, Thoothukudi Year and University : 2017, Tamil Nadu Fisheries UniversityTitle : Harnessing tropical brown seaweed to derive nutritional and functional seaweed based products. Name of the student : K.Vijay Degree : M.F. Sc. Chairman : Dr.S. Balasundari Department : Fish processing Technology School : School of Harvest and Post harvest Technology College : Fisheries College and Research Institute, Thoothukudi Year and University : 2017, Tamil Nadu Fisheries University Seaweeds possess different nutritive components and included as a functional food ingredient in various products. This study was undertaken to develop seaweed based biscuit and to assess its storage stability with respect to safety, nutritional and functional quality. Nutritional composition of different seaweed species viz Sargassum swartzii, Sargassum tennerimum, Sargassum wightii, Sargassum vulgare, Turbinaria ornata and Padina tetrastromatica collected from the coast of Gulf of Mannar was assessed and used to prepare seaweed based nutrient enriched biscuits. Sargassum swartzii had the highest protein content (17.63 ± 0.42%), while the lowest was found in Turbinaria ornata (14.25 ± 0.88%). Fat content was high in Turbinaria ornata (2.78 ± 0.29%) and low in Padina tetrastromatica (0.89 ± 0.02%). Ash was one of the most important constituents ranging from 34.33 ± 1.54 to 47.13 ± 2.34% in seaweeds and the highest value was recorded in Padina tetrastromatica and lowest in Sargassum wightii. Carbohydrate content varied widely in different seaweed species ranging from from 24.91 ± 1.76 to 28.95 ± 2.31%. Moisture content was more in dried Sargassum vulgare (15.95 ± 0.63%) and less in dried Padina tetrastromatica (9.03 ± 1.02%). In order to prepare seaweed nutrient enriched biscuits, Sargassum swartzii was considered due to its high availability as well as good nutritional value. Two different types of seaweed biscuits were prepared by incorporating 10 %(Seaweed Biscuit Type-I) and 20 %(Seaweed Biscuit Type-II) dried seaweed powder by replacing the wheat flour. The biscuits were air packaged and vacuum packaged in HDPE pouches and stored at ambient temperature. The storage stability of the seaweed biscuits was analysed for a period of 120 days by analyzing the moisture content, water activity, crispiness, Thiobarbituric acid (TBA), total plate count (TPC) and sensory attributes. Seaweed biscuit type-I contained 8.29% protein, 27.05% fat, 1.44% ash, 1.32% crude fiber, 57.38% carbohydrate. Mineral contents of the seaweed biscuit type-I was 0.93 g/100g K, 0.19 g/100g Ca, 0.18 g/100g Na, 9.01 mg/100g Fe and 1.31 mg/100g I, exceeded recommended dietary allowance limitRDA for Iodine. Seaweed biscuit typeII contained 10.20% protein, 27.96% fat, 1.92% ash, 1.72% crude fiber and 57.38% total carbohydrate. Mineral contents of the seaweed biscuit type-II was 1.87 g/100g K, 0.38 g/100g Ca, 0.01 g/100g Mg, 0.27 g/100g Na, 22.98 mg/100g Fe and 4.01 mg/100g I, which exceeded recommended dietary allowance-RDA for Iodine and Iron. During the storage period an increasing trend of moisture, water activity, Thiobarbituric acid (TBA) and loss of crispiness was observed in both the type of seaweed biscuits. However, air packaged seaweed biscuit type-I was found to be the best with regard to higher crispiness score, presence of minerals well within the recommended dietary allowance-RDA and longer shelf life of 100 days. The incorporation of dried seaweed powder of Sargassum swartzii in the biscuit preparation at 10% level will result in production of minerals and other nutritional elements enriched biscuits to the ever-increasing number of consumers. CONTENT Chapter No. TITLE Page No.