<![CDATA[Biscuit is a food product made from the basic ingredient fl our that baked until moisture content less than 5%. Commercial biscuits are generally rich in energy and high in sugars derive from carbohydrates and fats, but low infi ber. Seaweed (Eucheuma cottonii) and arrowroot fl our are high-fi ber food, while oyster mushroom contains high protein so it can be a potential ingredients to be substituted in biscuits. The addition of seaweed and oyster mushroom was expected to increase the fi ber content of biscuits compared to other biscuits. This study aimed to determine the acceptability and improve fi ber content in biscuits with the substitution of seaweed and oyster mushrooms. This study used a completely randomized design (CRD) with 3 treatments and 4 repetitions. Arrowroot fl our substitution treatment,seaweed, and oyster mushrooms were applied as F1 (25%: 50% to 25%), F2 (25%: 45%: 30%), and F3 (25%: 40%: 35%). Acceptability of biscuits based on organoleptic test and fi ber content from calculation based on Indonesia Food Composition Database and also laboratory analysis using proximate test. This research showed that formula 3 had the highest score based on organoleptic test with score 2.86. The highest fi ber content per serving (50 g) was found in formula 1 with 10.59 g of fi ber. The conclusion of this research is that the biscuit with substitution of seaweed andoyster mushroom has a good acceptability and higher fi ber content compared to commercial biscuits.Keywords: biscuit, oyster mushroom (Pleurotus ostreatus), seaweed (Eucheuma cottonii)]]>
