The effects of roselle extract addition on physical properties and organoleptic preferences of sorghum noodles

This research is intended to study the effect of roselle extract addition on physical, hedonic preferences, and nutrition facts of the sorghum noodles. The research is conducted using a Completely Randomized Design one factor with the concentrations of roselle extract were 0%, 10%, 20%, 30%. The analysis conducted were water absorption, color value, and organoleptic analysis with one-way ANOVA test followed by Duncan’s Multiple Range Test for statistical analysis. The results showed that addition of roselle extract significantly affect the physical and organoleptic properties of sorghum noodles. The high concentration of roselle extract caused an increment in rehydration power, redness value, yellowness value, and decrement in lightness value. The rehydration power of sorghum noodles was 65 to 115%, lightness 43.10 to 63.78, redness -5.57 to 0.50, and yellowness 22.71 to 30.96. Based on the organoleptic preference test, roselle extract concentration of 30% has the best organoleptic properties with the liking scores of color, aroma, taste, texture, and overall liking of 3.40, 3.47, 3.50, 3.53, and 3.53, from the range of 1-5 respectively. From the nutrition fact prediction, sorghum noodle with 30% roselle extract has the higher calcium, and potassium than sorghum noodle without roselle extract. Therefore, 30% roselle extract addition on sorghum noodles showed was the best result in physical properties and organoleptic preferences.


Introduction
Cholesterol is a natural substance with a steroidal formula and physical properties in the form of fat.In the human body, about 70% of the cholesterol in the blood is synthesized by the liver, while the rest comes from daily food intake [1].Cholesterol plays an important role in the formation of essential building blocks, where it helps synthesize important substances such as cell membranes, sex hormones, steroid hormones insulating materials around nerve fibers, vitamin D, and bile acids [2].However, excessive consumption of high-cholesterol foods, especially animal-derived foods that are rich in LDL (Low-Density Lipoprotein) may cause some health problems [3].According to Sigarlaki and Tjiptaningrum [4], the risk of health problems will increase by 1.8 times if the cholesterol level in the human body's blood is higher than the normal level, which is 200 mg/dl.The high cholesterol level in the blood is known as hypercholesterolemia.According to the Survei Kesehatan Rumah Tangga (SKRT) in 2004, hypercholesterolemia prevalence in the 25-34 year age group is 9.3% and increases with age, reaching 15.5% at the age of 53-64 years.In addition, based on the 2013 Riskesdas (Risket Kesehatan Dasar) report, it is known that the proportion of the population in Indonesia with high cholesterol levels above normal or experiencing hypercholesterolemia is 39.6% for women and 30% for men [5].Hypercholesterolemia has been treated in various ways, either through pharmacological therapy or nonpharmacological therapy.In pharmacological therapy, hypercholesterolemia can be handled by drugs from the statin group, simvastatin which acts as a competitive inhibitor that inhibits the enzyme 3-1324 (2024) 012119 IOP Publishing doi:10.1088/1755-1315/1324/1/012119 2 hydroxy-3-methylglutaroyl-coenzyme A (HMG-CoA) reductase.However, pharmacological therapy may cause various side effects including abdominal pain, nausea, hypersensitivity reactions, headaches, and many more [6].Therefore, non-pharmacological therapy, like nutritional therapy (restriction of the number of calories and fat, high fiber diet, healthy eating patterns) and increased physical activity (exercise) can be a good alternative with fewer side effects.Non-pharmacological nutritional therapy to treat hypercholesterolemic sufferers can also be assisted by the consumption of various healthy plants such as sorghum and roselle flower.
Sorghum (Sorghum bicolor) is a cereal grain that is rich in nutrients and phytochemical components which provide a significant impact on human health.Sorghum serves as a functional food product for the treatment of cardiovascular disease (CVD).In this case, sorghum has the ability to reduce LDL (lowdensity lipoprotein) cholesterol levels and improve HDL (high-density lipoprotein) cholesterol levels [7].The cholesterol-lowering effect of sorghum is due to its high dietary fiber content of sorghum.Sorghum contains dietary fiber which is approximately 9.3% [8].The dietary fiber is able to bind the bile acids in the intestine which causes the inhibition of bile acids reabsorption into the enterohepatic circulation [9].This phenomenon stimulates the liver to use cholesterol to form bile acids and reduces the absorption of cholesterol into the blood, so the cholesterol levels are reduced [10].Sorghum also contains various phytochemicals, such as phenolic compounds, policosanols, and sterols which possess a hypocholesterolemic effect [11].Policosanols lower the cholesterol level by reducing the activity of the rate-limiting enzyme in the synthesis of cholesterol which is 3-hydroxy-3-methylglutaryl coenzyme A reductase, also increasing the receptor activity of LDL [12].The cholesterol-lowering effect of policosanols is more effective compared to statin chemical drugs.This is in correlation with the research conducted by Castano et al. [13] which found that policosanol which is approximately 10 mg/day is more effective in lowering LDC cholesterol and improving HDL cholesterol compared to 20 mg/day of lovastatin.Besides that, phytosterol contained in the sorghum also can inhibit cholesterol absorption and lower the plasma concentration of LDL cholesterol [14].
The cholesterol-lowering effects of sorghum have been investigated.Research conducted by Carr et al. [15] showed that grain sorghum lipid reduces cholesterol absorption and the concentration of plasma non-HDL cholesterol with a reduction of 69% in hamsters fed with 5% grain sorghum lipid.Besides that, Kim et al. [10] reported that in high-cholesterol diet-fed mice, sorghum extract has the ability to decrease serum or liver cholesterol concentrations by reducing hepatic cholesterol production, mostly through the increment in active AMPK expression and the decrement in HMGCR, SREBP2, or FAS.One of the functional food products derived from sorghum grain is sorghum flour.Sorghum flour is sorghum-based flour that is produced from the milling process of sorghum grain.Sorghum flour contains 3.65% fat, 2.74% crude fiber, 2.24% ash, 10.11% protein, and 80.42% carbohydrates [16].Sorghum flour also consists of calcium in the range of 195-477 mg, 950-2147 mg potassium, 14.5-58.6mg sodium, 12-23 mg zinc, and 28.8-55.1 mg iron per kg sorghum flour [17].Sorghum flour can be used as a raw material or as a substitute for wheat flour in the manufacture of various types of food products, such as noodles [18].
Roselle plant which has the Latin name Hibiscus sabdariffa L. is a plant originating from India.The roselle plant belongs to the Malvaceae family and has two types, namely Hibiscus sabdariffa var.altassima and Hibiscus sabdariffa var.sabdariffa.The difference between these two types is Hibiscus sabdariffa var.altassima.contains higher and stronger fiber than Hibiscus sabdariffa var.sabdariffa.So, it is often used to make rope and burlap sacks.In Hibiscus sabdariffa var.sabdariffa.It has red petals and is edible to eat, also has fibrous stems.Roselle flowers have been used as a drink for health, the part of the roselle that is used as a drink is the calyx or flower petals.Calyx can be dried and brewed like tea, can also be mixed into juices, and for cake mixture that is added to the dough which aims as a natural colorant because these roselle flowers can produce a beautiful red color.In addition, the calyx of roselle can be utilized to make roselle jam, according to the study conducted by Mangindaan et al. [19].In Indonesia, roselle is still very rarely used, but as technology develops and food advances, roselle is often used because of its high nutritional content.Roselle tea contains antioxidants and protein and also contains 18 amino acids.The flower petals contain anthocyanins which can form flavonoids.
Anthocyanins from Roselle have 3 forms, namely cyanidin-3-sambubioside, delphinidin-3-glucose, and delphinidin-3-sambubioside.Anthocyanins are easily soluble in water, this thing makes roselle flowers after brewing will make the steeping water red [20].The brewing of roselle petals according to research conducted by Wahyuni [21] on mice with hypercholesterolemia concluded that a dose of roselle flower of 50 mg/kgbbw can reduce total cholesterol levels in mice.The antioxidant compounds of roselle can reduce cholesterol levels in the blood by preventing LDL oxidation [22].Roselle can reduce cholesterol because the high antioxidant in it which is flavonoids.According to Witosari and Widyastuti [23], giving the extracts of flavonoid compounds can reduce total cholesterol levels.
The functional properties of noodles can be improved through the utilization of sorghum flour and roselle extract in the production of noodles.Sorghum noodles with roselle extract can be alternative noodles for hypercholesterolemia sufferers which is capable to reduce LDL cholesterol levels.Different from the common noodles, this noodle innovation is substituted with sorghum flour.Sorghum flour produced from the milling process of sorghum plays a significant role in the reduction of LDL cholesterol.This is caused by sorghum flour rich in fiber approximately 2.74% [16].Besides that, sorghum which is the major component of the sorghum flour contains various bioactive components with cholesterol-lowering effects, such as policosanols, and sterols [15].Sorghum flour also provides other beneficial benefits, such as being gluten-free, high in protein, and having a lower glycemic index compared to wheat flour which does not cause a significant increase in blood glucose levels in diabetics [24].As a result, the incorporation of sorghum flour in the production of noodles increases the functional properties of noodles commonly made from wheat flour.The sorghum noodle is followed by the addition of roselle extract.The roselle extract also possesses cholesterol lowering effect and it is capable to increase HDL serum [25].The antioxidant contained in the roselle extract can prevent LDL oxidation, so the blood cholesterol level is reduced [22].Therefore, sorghum noodles with roselle extract have a big potential as alternative noodles with cholesterol-lowering effects which is suitable for the consumption of people with hypercholesterolemia. Basically, roselle has a unique red color and sour taste.Therefore, an appropriate formulation must be developed to produce sorghum noodles with roselle extract that possesses great physiochemical and sensory characteristics through this research.
Due to lot of health problems caused by cholesterol, the consumption of food that containing cholesterol should be limited and even be diminished.So, the food that regularly Indonesian consume day by day like noodles, should be developed to diminish the consumption of food containing lots of cholesterol by adding the component of antioxidant that can reduce blood cholesterol levels with hyperlipidemia.Roselle has lots of antioxidant compounds to reduce cholesterol, and also roselle is easy to mix with noodle dough through the water.So, the purpose of our research is to find out the physical and sensory differences between noodles using roselle flower extract from 10%, 20% to 30% with the comparison as control or noodles without the use of roselle flower extract.

Noodle making
The roselle flower used was dried flower purchased from greater Jakarta.This research used a Completely Randomized Design (CRD) with one factor which was the concentration of roselle extract with four treatments.All the treatments in this research can be expressed as: (1) P0: 0% roselle extract; (2) P1: 10% roselle extract; (3) P2: 20% roselle extract; and (4) P3: 30% roselle extract.
For making noodles (see Table 1 for the formulation), first mix 330 grams of high protein flour and 110 grams of sorghum flour, then add 1 egg, 22 mL or 1.5 tablespoons of oil, 2.5 grams or 0.5 teaspoon salt, and 100 mL water containing roselle extract.To make roselle extract,10 grams, 20 grams, and 30 grams of roselle flowers were dipped into 100 ml water for 10 minutes of each treatment, and then filtered and the roselle flower water can be mixed with the dough mixture.After all the dough is stirred until smooth and rested for 30 minutes.Furthermore, the dough can be flattened with a manual grinder and cut into thin and long pieces.

Water absorption (rehydration power) analysis
The experiments on the water absorption of sorghum noodles with the addition of roselle extract were conducted using the weighing method according to the study conducted by Billina et al. [26].The uncooked sorghum noodles with the addition of roselle extract were weighed 10 g.Then, the boiling process was done for 5 minutes, and the cooked sorghum noodles with the addition of roselle extract were weighed again as the cooked samples.The water absorption was calculated using the equation below, where WA was uncooked noodles weight (g) and WB was cooked noodles weight (g).

Color analysis
Color analysis of sorghum noodles with roselle extract was conducted with Color Lab mobile application which is available in Android.In this analysis, L* represents lightness which varies from 0 (black) to 100 (white).The procedure of color analysis will follow the using instruction for use of the software [27].

Organoleptic analysis
The organoleptic analysis is carried out in the form of a hedonic test with five parameters, which are color, aroma, texture, taste, and overall appreciation.The hedonic test in this study was referred to in the study conducted by Attahmid et al. [28] with some modifications.In the hedonic test, 30 untrained panelists were presented with a sample that had a certain number code.The sample that was presented was 10 grams of sorghum noodles with the addition of roselle extract.After the consumption, the panelists were asked to fill out an assessment regarding each sensory property of the sorghum noodles with the addition of roselle extract, starting from a score of 1 (dislike very much), 2 (dislike moderately), 3 (neutral), 4 (like moderately), and 5 (liked very much) on a questionnaire.

Nutrition fact prediction
Nutrition facts were obtained using very well fit software (https://www.verywellfit.com/recipenutrition-analyzer-4157076).The things that need to do with very well fit software is to input all the ingredients used in the manufacture of noodles along with their sizes from the control to using roselle flower extract 10%, 20%, and 30% formula.

Statistical analysis
The data analysis in this research was used XLSTAT software.Data obtained from the water absorption, color, and organoleptic analysis were analyzed through one-way ANOVA (Analysis of Variance) test with a significant level of 5% with post-hoc Duncan's multiple range test (DMRT) between treatments.

Water absorption (rehydration power) analysis
Water absorption or rehydration power is the ability of a food product to absorb water optimally.The rehydration power value indicates the amount of water absorbed by a food ingredient during the cooking process.The rehydration power of noodle products can be determined by calculating the weight of the noodles before and after the boiling process [29].Table 2 and Figure 1 shows the results of rehydration power analysis on sorghum noodles with different concentrations of roselle extract.As shown in Table 2 and Figure 1, the rehydration power of sorghum noodles has a value in the range of 65−115%.The rehydration power of sorghum noodles with 0% roselle extract concentration is not significantly different from sorghum noodles with 10% roselle extract.However, there is a significant difference in rehydration power between sorghum noodles with 0% roselle extract and sorghum noodles with 20% & 30% roselle extract.Besides that, sorghum noodle with 10% roselle extract is not significantly different from sorghum noodle with 20% roselle extract, but it is different significantly from sorghum noodle with 30% roselle extract.The rehydration power of sorghum noodles has a positive correlation with the concentration of roselle extract.The rehydration power of sorghum noodles increases as the concentration of roselle extract increases.In this case, sorghum noodle with 0% roselle extract has the highest rehydration power.The high rehydration power indicates the high amount of water that can be absorbed by the noodle.On the other hand, sorghum noodle with 30% roselle extract has the lowest rehydration power.This might be caused by soluble fiber content in roselle extract which capable to lower the rehydration power of noodles.The fiber content of roselle flowers is approximately 33.9% and the soluble dietary fiber of roselle extract is 0.66 g/L [30].The rehydration power of noodles is significantly affected by the presence of fiber.Fiber has the ability to absorb water due to its hydrophilic nature [31].

Color analysis
Generally, color can be defined as the impression of the eye senses on the light reflected by an object.
Color is one of the food attributes that significantly affect the consumer's acceptance or rejection of the food product [32].Color also can be a parameter that determines the quality of and the attractiveness of the food product.Table 3 shows the results of color analysis on sorghum noodles with different concentrations of roselle extract.As shown in Table 3, the L* value (lightness) of the sorghum noodles is in the range of 43.102−63.775.The lightness of sorghum noodles with 0%, 10%, 20%, and 30% roselle extract have significant differences each other.Sorghum noodle with 0% roselle extract has the highest L* value followed by sorghum noodle with 10% roselle extract and 20% roselle extract.Meanwhile, sorghum noodle with 30% roselle extract has the lowest L* value.The color analysis results show that the L* value of the sorghum noodle has a negative correlation with the concentration of roselle extract.In this case, the L* value of the sorghum noodle decreases as the roselle extract concentration increase.This result is in accordance with the research conducted by Angela et al. [34] which reported that the higher concentration of the roselle extract in the Monascus-fermented durian seed jelly drink leads to a lower L* value.This is caused by the increment in the concentration of roselle extract causes the sorghum noodles to become darker due to the anthocyanin pigment contained in the roselle extract.Basically, roselle extract derived from the roselle petals has anthocyanin pigment as the main color pigment [33].The addition of roselle extract to the sorghum noodle causes the appearance of the brownish color on the noodles after the boiling process.This occurs due to the degradation and polymerization of the anthocyanin pigment [34].The anthocyanin pigment is sensitive and unstable to heat [35].In this process, the anthocyanin degradation process begins with the hydrolysis of glycosidic bonds of anthocyanins which involves the release of glycosyl groups from anthocyanin resulting in unstable aglycones [36].The aglycone ring opens from flavylium cation and forms the carbinol compound and colorless chalcone group.Therefore, sorghum noodle with 30% roselle extract has the lowest L* value among all treatments.
The a* (redness) value of the sorghum noodle ranged from -5.567 to 0.503.The redness of sorghum noodles with 0%, 10%, 20%, and 30% roselle extract have significant differences from each other.The a* value increases along with the concentration of the roselle extract.Sorghum noodle with 0% roselle extract has the lowest a* while sorghum noodle with 30% roselle extract has the highest a* value.This is caused by roselle extract containing anthocyanin which is a water-soluble pigment that is included in the flavonoid group and gives a red color [37].The high roselle extract concentration indicates the high anthocyanin level contained in the extract which provides a high red color intensity.As a result, sorghum noodle with 30% roselle extract concentration has the highest red color intensity resulting in the highest a* value among all treatments.Research conducted by Ekie & Evanuarini [38] also found that the a* (redness) of the milk candy has a positive correlation with the concentration of roselle powder which the a* increase as the concentration of roselle powder increases.Besides that, the b* (yellowness) value of the sorghum noodle varied from 22.708−30.964.The roselle extract does not differ significantly from sorghum noodle with 10% roselle extract.However, there is a significant difference in yellowness between sorghum noodles with 0% roselle extract and sorghum noodles with 20% & 30% roselle extract.
Besides that, the yellowness of sorghum noodles with 10% roselle extract is different significantly from sorghum noodles with 20% & 30% roselle extract concentration.Sorghum noodle with 30% roselle extract concentration is different significantly from all treatments in this research.The b* value of sorghum noodle increases as the roselle extract concentration increases.All of the treatments have a positive b* value.This indicates that the sorghum noodle tends to be yellowish, and the yellow intensity increase along with the increment of roselle extract concentration.Overall, this sorghum noodle highlights a yellow tone more than the red tone due to the utilization of other ingredients, such as wheat flour and sorghum flour which causes the red color of the roselle extract becomes fade.

Organoleptic analysis
Organoleptic analysis was conducted using the hedonic test.Basically, hedonic test is a sensory analysis conducted to know how big the difference in quality between several similar products by giving an assessment or score towards certain sensory parameters of a product.The hedonic test also helps to determine the level of preference of a product [39].Table 5 and Figure 2 shows the results of organoleptic preferences (hedonic test) of sorghum noodles with different concentrations of roselle extract.

Figure 2. Hedonic Test
Color is a visual profile that serves as the first impression in assessing a food product [40].Food product with attractive color is capable to increase the acceptance of the consumer.The results of the hedonic test in the terms of color on sorghum noodles with different concentrations of roselle extract are expressed in Table 5 and Figure 2. The ANOVA result with a significance level of 5% shows that the concentration of roselle extracts significantly affect the liking of the color of the sorghum noodle (P<0.05).Then, the Duncan Multiple Range Test (DMRT) at a level of 5% shows that the color liking score of sorghum noodles with 0% roselle extract is significantly different from sorghum noodles with 10%, 20%, and 30% roselle extract.However, there is no significant difference in the liking of color score among sorghum noodles with 10%, 20%, and 30% roselle extract.Sorghum noodle with 20% and 30% roselle extract has the highest liking score of color while sorghum noodle with 0% roselle extract has the lowest liking score of color.The liking score of the color of sorghum noodles increases as the roselle extract concentration increases.This is caused by sorghum noodles with a high concentration of roselle extract having a yellowish into brownish color which is more preferred by the panelists.The appearance of yellowish inti brownish color due to the anthocyanin pigment contained in the roselle extract.Roselle extract contains anthocyanin pigment as its main color pigment [33].Anthocyanin is sensitive to heat.The degradation of anthocyanin pigment due to the heating process leads to the formation of yellowish or brownish color [34].On the other hand, sorghum noodle with 0% roselle extract has a dominant pale white color which is not preffered by consumer.
The results of the hedonic test in the terms of aroma on sorghum noodles with different concentrations of roselle extract are expressed in Table 5 and Figure 2. As shown in Table 5 and Figure 2, the like of aroma in the sorghum noodle with the addition of roselle extract has a value in the range of 3.03-4.67.The analysis of variance (ANOVA) result using a 5% significant level shows that the concentration of roselle extract does not affect the aroma of the sorghum noodles with the addition of roselle extract (P>0.05).Furthermore, the Duncan Multiple Range Test (DMRT) at a level of 5% shows that the likeable aroma of the product is significantly different between noodle with 0% roselle extract and treatment noodle with 30% roselle extract.However, there is no significant difference between noodles with 0% roselle extract and noodles with 10% and 20% roselle extract.The increase in the aroma of the sorghum noodle was correlated with the concentration of roselle extract increasing.In this case, sorghum noodle with the addition of 30% roselle extract has the highest liking score of aroma.This can happen because, basically, roselle has a distinctive aroma which is sour.This sour aroma is produced by the roselle petals that have a refreshing citrus aroma from several acidic compounds contained.The aroma produced by roselle flowers or extract helps to cover up the unpleasant aroma from the sorghum flour, the base material of the noodles which is usually unpreferred by a lot of people.Therefore, the higher the roselle extract contained in the sorghum noodle, the more preferable the product by the panelists.This is in accordance with the study conducted by Afifah et al. [41], where the sour aroma of roselle extract helps in the loss of the distinctive aroma of soya yogurt.
The results of the hedonic test in the terms of taste on sorghum noodles with different concentrations of roselle extract are expressed in Table 5 and Figure 2. As shown in Table 5 and Figure 2, the likeness of taste in the sorghum noodle with the addition of roselle extract has a value in the range of 3.07-3.50.The analysis of variance (ANOVA) result using a 5% significant level shows that the concentration of roselle extract does not affect the taste of the sorghum noodles with the addition of roselle extract (P>0.05).Furthermore, the Duncan Multiple Range Test (DMRT) at a level of 5% shows that the likable taste of the product is significantly different between the noodle with 0% roselle extract and the treatment noodle with 30% roselle extract.However, there is no significant difference between noodles with 0% roselle extract and noodles with 10% and 20% roselle extract.The increase in the taste of the sorghum noodle was correlated with the concentration of roselle extract increasing.In this case, sorghum noodle with the addition of 30% roselle extract has the highest liking score in terms of taste.This can happen because, basically, roselle extract is capable of giving a sour taste, which comes from several components such as ascorbic acid, maleic acid, hibiscus acid, oxalic acid, tartaric acid, and glycolic acid [41].On the other hand, sorghum flour is capable of giving a bitter yet astringent taste to the noodle [42].The sour taste produced by the roselle may help to cover the bitter yet astringent taste of the sorghum-based noodles, which is usually unpalatable to a lot of people.As a result, the higher the percentage of roselle extract in the sorghum noodle, the more preferred the product was by the panelists.
The results of the hedonic test in terms of texture on sorghum noodles with different concentrations of roselle extract are expressed in Table 5 and Figure 2. As shown in Table 5 and Figure 2, the likeness of texture in the sorghum noodle with the addition of roselle extract has a value in the range of 3.067-3.533.The analysis of variance (ANOVA) result using a 5% significant level shows that the concentration of roselle extract affects the texture of the sorghum noodles with the addition of roselle extract (P<0.05).Furthermore, the Duncan Multiple Range Test (DMRT) at a level of 5% shows that the likable texture of the product is significantly different between the noodle with 0% roselle extract and the treatment noodle with 20% and 30% roselle extract.However, there is no significant difference between noodles with 0% roselle extract and noodles with 10% roselle extract.On the other hand, the noodle with 10% roselle extract is not significantly different from the noodle with 20% and 30% roselle extract.Last, the noodle with 20% roselle extract is also not significantly different from the noodle with 30% roselle extract.The increase in the taste of the sorghum noodle was correlated with the concentration of roselle extract increasing.In this case, sorghum noodle with the addition of 30% roselle extract has the highest liking score in terms of taste.This can happen because, basically, sorghum-based flour has a sandy texture that is not preferable for noodle products [43].The use of roselle extract in the sorghum-based noodle helps to make the noodle less sandy in texture.Therefore, the higher the percentage of roselle extract in the sorghum noodle, the more preferred the product was by the panelists.
The results of the hedonic test in terms of overall liking on sorghum noodles with different concentrations of roselle extract are expressed in Table 5 and Figure 2. As shown in Table 5 and Figure 2, the overall liking of the sorghum noodle with the addition of roselle extract has a value in the range of 3.17-3.53.The analysis of variance (ANOVA) result using a 5% significant level shows that the concentration of roselle extract affects the overall of the sorghum noodles with the addition of roselle extract (P<0.05).Furthermore, the Duncan Multiple Range Test (DMRT) at a level of 5% shows that there is no significant difference between each sample.The increase in the overall liking of sorghum noodles was correlated with the concentration of roselle extract increasing.In this case, sorghum noodle with the addition of 30% roselle extract has the highest overall liking score.This can happen because the higher the roselle extract contained in the sorghum noodle, the more preferable the product in aroma and taste due to the sour taste and aroma of roselle extract.The sour taste and aroma of roselle extract are capable of covering up the distinctive taste and unpleasant aroma of sorghum-based noodles [41].Besides, the higher roselle extract may help to reduce the sandy texture of sorghum-based noodles.Last, the higher roselle extract also produces a more appetizing color, which is a brownish color due to the anthocyanin content in roselle [34].

Nutrition fact
The nutrition fact of sorghum noodles with different concentration of roselle extract is expressed in Table 4. From the table above, it was found that the calcium and potassium increased with the increasing concentration of roselle flower tea.This is because the more roselle flowers were brewed, the more calcium ions and potassium ions dissolved in water.This made the calcium and potassium in nutrition facts also increase along with the addition of roselle extract added to the noodle dough.
Sorghum noodles have an astringent and bitter taste.The bitter and astringent taste of sorghum flour can be caused by the high tannin content in sorghum itself as the base material of sorghum flour [44].The addition of roselle extract reduces the astringent and bitter tastes from sorghum noodles.Not only that, the roselle extract also gives a little hint of sour taste, which comes from the citric acid compounds of the roselle flower [41].On the other hand, sorghum noodle with roselle extract also has an aroma and texture that is not preferable to a lot of people.This can be said because the base material, which is sorghum, used in the development of the product has an unpleasant aroma and a sandy texture [45].Then, the sorghum noodle with roselle extract also has a less chewy texture compared to the general noodle made with wheat flour.This texture result can be caused by the gluten-free characteristic of sorghum flour [44].
The use of sorghum and roselle extract gives health benefits by lowering cholesterol levels which may be developed into functional food.Functional food is basically a food that naturally or through a process has active ingredients in it that have the potential to provide health benefits beyond the benefits provided by the basic nutritional content [7,21,45].

Conclusion
From the research, the rehydration power of sorghum noodles increases as the concentration of roselle extract increases.The sorghum noodle with 0% roselle extract has the lowest rehydration power while sorghum noodle with 30% roselle extract has the highest rehydration power.From the color analysis, the addition of roselle extract to the sorghum noodle causes the appearance of the brownish color on the noodles, so the most brownish color on the noodles is the noodles use 30% roselle extract.From the nutrition facts, the noodle made with 30% roselle flower extract has the higher calcium and potassium content compared with the control.From the organoleptic analysis, the liking of aroma and taste have the highest score in the noodles with the addition of 30% roselle extract, this means panelists most like is the noodles with 30% roselle extract.Therefore, it can be concluded that the roselle extract concentration of 30% on sorghum noodles gives the best treatment.

Table 1 .
Formulation of sorghum noodles with roselle.

Table 2 .
Rehydration power analysis of sorghum noodles with the addition of roselle extract

Table 3 .
Color analysis of sorghum noodles with the addition of roselle extract.

Table 4 .
Hedonic test (1-5 scale) of sorghum noodles with the addition of roselle extract.

Table 5 .
Nutrition fact of sorghum noodle with roselle extract.