Abstract:
Seaweeds are macroalgae that grow in coastal regions and are a good source of nutrients.
However, they are rarely used in functional foods. Therefore, this study aimed to enhance
seaweed consumption as a functional food among Sri Lankans by developing a seaweed
incorporated jam. The marine seaweed, Ulva lactuca, collected from Thalalla rocky shore area of
the Southern coast of Sri Lanka, was thoroughly washed, cleaned with water several times and
pre-treated with hot-water blanching. Jam was prepared by mixing Ulva with different fruit pulps,
namely mango, pineapple and passion fruit peel. Preliminary sensory evaluations identified
yellow passion fruit peel as the most suitable fruit pulp for incorporation with Ulva. A series of
jam samples were developed using different ratios of air-dried (ADT1-4) and oven-dried (ODT1-4)
Ulva powder with fruit pulp and sugar. The ratios for ADT1-4 were1:1:2, 1:2:3, 1:3:4 and 1:4:5,
while those for ODT1-4 were1:8:10, 1:9:11, 1:10:12 and 1:11:13. The best ratio was selected
through sensory evaluations conducted by 37 untrained members, assessing appearance, texture,
taste, sweetness, aroma, spreadability, and overall acceptability using a five-point Hedonic scale.
Sensory data revealed that jam prepared with oven-dried Ulva powder, yellow passion fruit peel
pulp and sugar in a 1:9:11 ratio (ODT4) was significantly preferred. This jam contained 33.51%
moisture, 3.89% total minerals, 0.17% crude fat, 8.61% crude fiber, 4.56% crude protein and
49.03% carbohydrate, with an energy content of 215.85 kcal/g. It also showed that a total
antioxidant capacity of 61.68 mg AAE/g, 65.30 ± 1.07 °Brix and pH 6.15. Shelf-life studies
indicated that the product remain consumable for over three weeks under refrigerated conditions
(4 °C). In conclusion the developed seaweed-based fruit jam offers an affordable, nutrient-rich
and novel confectionary product for consumers.