![](bg1.png)
Effect of Comparative Flour of Purple Sweet Potato (Ipomea batatas)
and Wheat Flour of Nutrition Value on Brownies
Emma Zaidar
*
, Rumondang Bulan, Firman Sebayang, M. Zulham Efendi Sinaga and Rina Latipah
Departement of Chemistry, Faculty of Mathematics and Natural Sciences, Universitas Sumatera Utara, Medan, Indonesia
Keywords: Purple Sweet Potato Flour, Carbohydrates, Proteins, Fats and Antioxidants.
Abstract: Determination of protein, fat and carbohydrates of brownies with variations of purple sweet potato flour
comparison with wheat flour. Brownies flour made with variation ratio of purple sweet potato flour with
wheat flour that was (80:20), (60; 40), (40:60) and (20:80) with a total weight of 100 grams of flour. The
protein content was determined by the Kjeldahl method, fFat content was determined by continuous
extraction, carbohydrate content was determined by counting aliquots weight reduction as the results of
moisture, ash, protein and fat. The result showed the highest protein content in variation (40:60) which is
7.09% and the lowest (80:20), which is 3.23%. The more purple sweet potato flour added the protein in
brownies was increase. The highest fat content in variation (20:80) is 18.60% and the lowest (80:20) and
(60: 40), which is 0.63%. The more the flour was added the fat content of the brownies was increase. The
highest levels of carbohydrates obtained from the reduction of protein, fat, water and ash. Furthermore, the
antioxidant test on purple sweet potato flour which has antioxidants that are very good for consumption
which have IC50: 173.14 mg / L.
1 INTRODUCTION
Purple sweet potato is one type of sweet potato is
widely grown in Indonesia. Purple sweet potato
contains of nutrients are rich in vitamins (B1, B2, C
and E), minerals (Ca, Mg, K and Zn), dietary fiber
and carbohydrates. Also, purple sweet potato has a
fairly dense purple color for their anthocyanin
pigmen that has spread from skin to the meat section
of the yam. The protein content cultivars are mostly
between 1.5% and 2.5%, including low to moderate
when compared to other vegetables. Although the
quality of protein is rather balanced, there are very
few sulfur-containing amino acids. The sweet potato
is a good source of vitamin C and vitamin B.
(Rubatzky, 1998).
Besides having a great production, which is
about 15-20 tonnes / ha (Joseph et al., 2003) The
stability and a higher anthocyanin content in purple
sweet potato from another source, make it as an
alternative to natural dyes (Kano et al. 2005). Purple
sweet potato convert into flour is one way to save
and preserve the purple sweet potato. Sweet potato
starch is broken down from yams which eliminated
most of water content about 7% (Sarwono, 2005).
Brownies is one type of pound cake. Brownies has
two type which is brownies and baked brownies.
Cake brownies has a constant structure as when the
brownies was cut its looks uniform from pore
crumbs and eaten soft also moist texture.
2 MATERIALS AND METHODS
Brownies production was divided into several steps.
The first step, butter was heated. The second step, 3
eggs were whipped with 100 ml sugar. Then, second
step was mixed and was added with ½ tbsp Baking
powder, ¼ tbsp butter then mixed until homogeny
for 20 minutes. Next step added 100 g of flour with
variation of purple sweet potato flour with wheat
flour (20: 80; 40: 60; 80:20; 60:40). All component
was added mixed and stirred until distributed. Then
added 3 tbsp cocoa powder, chocolate bars, and
melted butter. Then stirred until evenly distributed
over 5 minutes and put into baking pan or for 35-40
minutes.
182
Zaidar, E., Bulan, R., Sebayang, F., Efendi Sinaga, M. and Latipah, R.
Effect of Comparative Flour of Purple Sweet Potato (Ipomea batatas) and Wheat Flour of Nutrition Value on Brownies.
DOI: 10.5220/0008865701820186
In Proceedings of the 1st International Conference on Chemical Science and Technology Innovation (ICOCSTI 2019), pages 182-186
ISBN: 978-989-758-415-2
Copyright
c
2020 by SCITEPRESS – Science and Technology Publications, Lda. All rights reserved