Organoleptic and Physicochemical Characteristics of Cake Based on Brown Rice Flour ( Oryza sativa L.) Modified Warumbia Cultivar

. Currently, the use of rice flour in making cakes is much needed by those who experience gluten allergy problems. The objective of this research was to evaluate the effect of using Warumbia cultivar brown rice flour modified using crude enzyme amylase from tempe mold and lactic acid bacteria on the organoleptic and physicochemical characteristics of cake. This research used a Completely Randomized Design (CRD). The data analysis used was the ANOVA test and further test (T test). The selected treatment for the organoleptic test was the modified brown rice flour treatment using BAL SBM.4A with a score of liking assessment of color, aroma, taste and texture respectively 3.78 (like), 4.25 (like), 4.08 (like) and 4.08 (like). The physical characteristics with the values of swelling power, porosity, kamba density and cake texture hardness are respectively: 105.67%, 0.21 cm, 0.39 g/mL and 0.85 (kg/cm 2 ). The proximate values of the cake were water content (19.23%wb), ash (0.86%wb), fat 23.90 (%wb), protein 9.54 (%wb), and carbohydrate 46.47 (%wb). The research results show an increase in the physical, chemical and organoleptic characteristics of cakes derived from modified brown rice flour process.


Introduction
Rice is one of the main food commodities for people in Indonesia which has a high carbohydrate content and can function as a natural functional food.Based on the Central Statistics Agency for Southeast Sulawesi [1], total rice production in Southeast Sulawesi Province reached 308 thousand tons.North Buton is one of the regions in Southeast Sulawesi Province, located on Buton Island which has 22 types of organic rice, including brown rice with productivity reaching 2.5 tons per Ha [2].Rice, which is generally consumed directly, can also be processed into flour so that it can produce various processed products.
Rice flour generally still has weaknesses in its characteristics, such as in bread making the ability to retain gas when the dough rises as a whole is very low [3], and the results of some of the processed products have a hard and rough texture.This weakness causes the processing of various food products from rice flour to be limited.Therefore, it is necessary to carry out a modification method to improve the characteristics of the rice that will be produced [3].One way to modify rice flour is by fermentation.The addition of microbes to the flour-making process can improve the quality of the flour [4].
Previous research reported that the physicochemical characteristics of Warumbia cultivar brown rice flour using crude enzyme amylase from tempe mold with the best fermentation time of 6 hours had a viscosity value of 29.16 cP, swelling power of 11.49 g/g, water solubility index of 25.60%, and pH 5.14 [4].Modification of Warumbia cultivar brown rice flour using BAL SBM.3D with the best fermentation time of 48 hours produced a viscosity value of 21.91 cP, swelling power of 9.15 g/g, water solubility index of 31.73%, and pH 6. [3].Apart from that [5] also reported that the physicochemical characteristics of brown rice flour from the Warumbia cultivar modified BAL SBM.4A with the best fermentation time of 48 hours obtained a viscosity value of 19.04 cP, swelling power of 10.50 g/g, solubility index, water of 33.33%, and pH 5.66.Therefore, Warumbia cultivar brown rice flour modified with crude enzyme amylase from tempe mold, BAL SBM.3D and BAL SBM.4A is used as an alternative to wheat flour in processing cake products.
Cake is a baked dough made from wheat flour, sugar, eggs and fat [6].In general, cakes are made with wheat flour as the basic ingredient, which causes wheat flour consumption to increase.To reduce the use of wheat flour, one alternative for making cakes was chosen using modified brown rice flour which is expected to produce cake products that are rich in nutritional content and beneficial for health.
Based on the description above, it is necessary to carry out research on the organoleptic and physicochemical analysis of cakes based on brown rice flour (Oryza sativa L.) modified Warumbia cultivar using crude enzyme amylase from tempe mold, BAL SBM.3D and BAL SBM.4A so that it can produce cake products that are have good quality.

Material
The ingredients used in making brown rice cake were rice flour.Supporting ingredients include sugar, butter, chicken eggs and baking powder.The materials used for analysis consisted of distilled water, standard protein solution BSA bovine serum albumin (Sigma), Biuret reagent (Merck), n-hexane (Merck), CaCO3 (Merck) and 0.1 N NaOH (Merck).

Research design
This research used a Completely Randomized Design (CRD).The treatments in this research were S1 (unmodified brown rice flour), S2 (modified brown rice flour with crude enzyme amylase), S3 (modified brown rice flour BAL SBM.3D), S4 (modified brown rice flour SBM.4A).Each treatment was repeated 4 times, so that in total there were 16 experimental units.

Making rice flour
Making brown rice flour, namely brown rice, is done by washing, slicing, baking, milling or flouring, then sieving to obtain fine flour using a 100 mesh sieve [5].

Cake making
Making cakes based on Warumbia cultivar brown rice flour was carried out separately between control, crude amylase enzyme modified brown rice, BAL SBM.3D, and SBM.4A.The initial step is to weigh other ingredients such as 100 g brown rice flour, powdered sugar 100 g, butter 100 g, eggs 156 g, and baking powder 2 g.Put granulated sugar and eggs in a container, then beat using a mixer at high speed for 15 minutes until fluffy.After expanding, the melted butter and baking powder are put into a container.Then beat again using a mixer at medium speed until all ingredients are evenly mixed and modified or unmodified brown rice flour is added little by little until the mixture is homogeneous.After the mixture is homogeneous, then pour 25 g into the mold.The molding process is carried out to produce a uniform cake size.After that, the dough in the mold is placed in the oven for 25 minutes at 180 o C [7].

Organoleptic assessment
The organoleptic assessment includes the texture, aroma, color and taste of the brown rice cake product for each treatment, to determine which brown rice cake product is most liked by the panelists.This test is based on giving panelists scores on color, texture, aroma and taste.The test used 40 untrained panelists.The assessment score given is based on hedonic test criteria.In this test, panelists were asked for their responses to the aroma, taste, color and texture with the scale used being 1= really don't like it, 2= don't like it, 3= like it a bit, 4= like it, 5= like it a lot.

Physical analysis
Physical analysis of brown rice cake includes swelling power using the method reported by [2], physical analysis of porosity using the method reported by [8], camba density analysis method carried out by [9], and hardness Texturing is done using the method [8]

Proximate analysis
Proximate analysis is water content using the thermogravimetric method [10], ash content using the thermogravimetric method [10], fat content using the Soxhlet extraction method [10], protein content using the Kjeldahl method [10], and protein content using the Kjeldahl method [10], carbohydrates using the by difference calculation method.

Data analysis
Observation data were analyzed using a Completely Randomized Design (CRD) test of variance.If the results of the analysis of variance show that the calculated F value > F table α=0.05 means that the treatment has a real effect on the response variable, then proceed with a further T test with a confidence level of 95% to determine whether the responses are significantly different or not significantly different.Physicochemical data analysis of modified Warumbia brown rice cake was calculated using the SAS application.

Organoleptic assesment
Organoleptic tests were carried out to determine the selected treatment by comparing Warumbia brown rice cake without modification with Warumbia brown rice cake with modification.Recapitulation results of the analysis of various organoleptic assesment for Warumbia brown rice cake can be seen in Table 1.Based on Table 1, the results of the analysis of various organoleptic tests for hedonic assessment show that the texture and taste parameters have a very real influence, while the color and aroma parameters have a real influence.Descriptive organoleptic assessment has a very significant effect on color, aroma, texture and taste.The results of the analysis of modified brown rice cake variations on hedonic and descriptive organoleptic preference parameters covering aroma, taste, texture and color of cake products are presented in Table 2 and Table 3.Based on the results of the analysis of organoleptic assesment on hedonic and descriptive scales in Table 2 and Table 3, it can be seen that the average level of panelists' assessment of the selected treatment S4 (modification with BAL SBM.4A) is the level of panelists' liking for the assessment parameters (color, aroma, taste, and texture) of modified brown rice flour cake is higher than unmodified brown rice flour cake.Meanwhile, in the descriptive scale organoleptic assesment, the level of assessment of the color parameter in treatment S1l was 4.18 (brown) and the selected treatment S4 (modification with BAL SBM.4A) was 3.28 (slightly brown).The aroma parameter for treatment S1 is 4.13 (brown rice aroma) and for the selected treatment S4 (modified with BAL SBM.4A) it is 3.45 (slightly brown rice aroma).In the taste parameter of treatment S1 the average was 4.00 (strong brown rice taste) and in the selected treatment S4 (modification with BAL SBM.4A) it was 3.38 (rather strong brown rice taste).Meanwhile, the texture parameter for treatment S1 is 3.45 (somewhat soft) and for the selected treatment S4 (modification with BAL SBM.4A) it is 3.70 (soft).The appearance of the brown rice cake can be seen in Fig. 1.

Color of the cake
Cake color is the first sensor that can be seen directly by panelists.Color has an important role in attracting consumers to food products and is also an identification mark and is a quality attribute of a food product which is very easy to detect if there is a change in quality [11].In the cake organoleptic test, the color parameters can be seen in Table 2.Where the color of the cake in treatment S2 (brown rice flour modified crude enzyme amylase) was preferred by panelists with a mean value of 4.15 (liked) compared to the control cake of 3.75 (liked).The panelists' assessment of the descriptive organoleptic cake color in Table 3 shows the S2 treatment (Warumbia brown rice flour modified crude enzyme amylase) with a mean value of 4.53 (very brown in color).The brown color of a baked cake can be influenced by the fat content in the flour used.According to Artaty [12] that the brown color of cake is caused by the high fat content in the flour so that when baked it will form a dark brown color due to the influence of heating.Crude enzyme amylase modified brown rice flour has a higher fat content of 2.74 (%db) compared to the fat content of control brown rice flour of 1.54 (%db) [4].

Aroma of the cake
Aroma of cake is the odor produced by chemical stimulation that is smelled by the olfactory nerves in the nasal cavity when food enters the mouth.In Table 2, the results of the hedonic organoleptic test for cake aroma were obtained in the selected treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) with the highest mean value of all treatments, namely 4.25 (like).If we look at the panelists' assessment of the descriptive organoleptics of cake aroma in Table 3, it shows that treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) has a mean value of 3.45 (slightly aromatic of brown rice).The cake made from brown rice flour which was most liked by the panelists had the criteria of having a slightly brown rice aroma.This is in line with research by [12] who reported that the aroma of roll cake made from black rice flour which was preferred by panelists was treated with a ratio of black rice flour to wheat (70:30) (slightly aromatic of black rice) with a score of 3.79 (liked) and the lowest score was in the treatment with a ratio of black rice and wheat flour (90:10) (black rice aroma) with a score of 3.33 (rather like it).This is thought to be due to the fermentation treatment of brown rice.The fermentation process causes starch granules to undergo hydrolysis to produce monosaccharides as raw material to produce organic acids, especially lactic acid.These compounds are mixed in the flour so that when the flour is processed it will produce a distinctive aroma and taste which can mask the aroma and taste of the base ingredients before fermentation which consumers tend not to like [13].

Taste of the cake
Cake taste is a compound or mixture of chemical compounds that can affect the body's senses, for example the tongue as the sense of taste [11].Based on Table 2, the results of the hedonic organoleptic test on the taste of the cake in the selected treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) were obtained with a mean value of 4.18 (liked) which was higher than the control cake, which was 3.98 (liked).However, if we look at the panelists' assessment of the descriptive organoleptic taste of the cake in Table 3, it shows that treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) with a mean value of 3.38 (rather strong brown rice taste) while the control cake (S1) with a value mean of 4.00 (strong brown rice taste).Modification treatment on Warumbia brown rice using LAB reduces the taste of brown rice in the cake.The reduced taste of brown rice in cake products can be caused by the fermentation process in brown rice.The fermentation process causes starch granules to undergo hydrolysis to produce monosaccharides as raw material to produce organic acids, especially lactic acid.These compounds are mixed in the flour so that when the flour is processed it will produce a distinctive aroma and taste which can mask the aroma and taste of the base ingredients before fermentation which consumers tend not to like [13].

Texture of the cake
Texture is a sensation of pressure that can be observed by looking and feeling when bitten, chewed, swallowed or touched with the fingers [14].In Table 2, the results of the hedonic organoleptic test for cake texture in the selected treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) are obtained with a mean value of 4.08 (like) compared to the control cake, namely 3.45 (somewhat like).Meanwhile, the panelists' assessment of the descriptive organoleptic cake texture in Table 3 shows that the S4 treatment (Warumbia brown rice flour modified BAL SBM.4A) has a softer texture with a mean value of 4.00 (soft) compared to the control cake texture with a mean value of 3.45 (a bit soft).According to [3], cake texture can be influenced by the level of fineness of the flour.Fermentation treatment of modified brown rice flour using BAL SBM.4A produces modified brown rice flour with a finer flour texture than unmodified brown rice flour [5].The finer the texture of the flour, the softer the resulting cake texture will be.

Physical test of warumbia brown rice cake
The results of the T test on the physical characteristics of modified Warumbia brown rice cake on the values of swelling power, porosity, camba density and texture hardness can be seen in Table 4. Based on Table 4, the results of the physical test of Warumbia brown rice cake on the swelling power in the S4 treatment (modification using BAL SBM.4A) was 105.67 (%), while in the treatment without modification (control) it was 94.76 (%).The Porosity value of brown rice cake in the S4 treatment (modification using BAL SBM.4A) was 0.38 (cm) greater than the treatment without modification (control) which was 0.20 (cm).The kamba density value of Warumbia brown rice cake in the S4 treatment (modification using BAL SBM.4A) was 0.39 (g/mL) lower than in the treatment without modification (control), was 0.60 (g/mL).The physical test value for texture hardness of Warumbia brown rice cake was greatest in the S4 treatment (modification using BAL SBM.4A) was 0.95 (kg/cm 2 ) and in the treatment without modification (control) was 1.58 (kg/cm2).

Degree of cake expansion
Expanding power or degree of cake expansion is a comparison of the size of the baked cake with the size of the cake dough before baking, so that the size of the cake is known.Based on the results of the T test, the swelling power of the selected treatment cake S4 (Warumbia brown rice flour modified BAL SBM.4A) in Table 4 shows that the swelling power value was 105.67 (%) higher than the control cake of 94.76 (%).This can be influenced by the swelling power of the flour.The high swelling power value in flour shows that the ability of amylopectin in starch to absorb water is high [5].So it can influence the increase in cake expansion power.According to Imam et al. [15], amylopectin contributes to increasing development value because amylopectin easily captures water.The protein content in flour can also affect the cake's rising ability.This is in accordance with the statement by Picaully [16] stated that the addition of sword koro protein isolate was able to increase the expansion volume of the cake.This is because the protein content plays a role in forming foam and to emulsify fat better, causing a higher swelling volume.BAL SBM.4A modified brown rice flour has a higher protein content, was 6.75 (%wb) compared to control brown rice flour, was 4.75 (%wb) [5].

Porosity of cake
Porosity is the pores found in the cake after the baking process.Based on the data in Table 4, it shows that the cake porosity value in the selected treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) was 0.38 (cm) higher than the control cake porosity of 0.20 (cm).This can be influenced by the water content of the flour.According to Saputri [5] that excessive water content causes excessive expansion during baking and produces bread with a large volume, but this also causes the pores of the bread produced to become larger.BAL SBM.4A modified brown rice flour has a greater water content, namely 8.06 (%) compared to unmodified brown rice flour of 7.18 (%) [5].According to Putri [17], the increase in porosity is due to the increase in dough water content which causes the pore size to increase and can expand the dough volume.

Camba density of cake
Camba density is a ratio between the weight of the material and the volume of space it occupies, including the empty space between the grains of the material [16].The formation of a porous structure due to air and water vapor being trapped and expanding during baking will reduce the density value of the cake product.Based on the data in Table 4, it shows that the camba cake density value in the selected treatment (S4) was 0.39 (g/mL) lower than the control, that is 0.60 (g/mL).This can be influenced by the cake baking process.According to Manley [9], the decrease in camba density is caused by changes in the dough during the baking process, namely a large reduction in product density which is related to the formation of an open porous structure.The porous structure formed causes the product to develop higher so that the cake volume becomes larger.This causes the camba density to decrease.The appearance of the porosity of Warumbia brown rice cake can be seen in Fig. 2 (a) (

Texture hardness of cake
Hardness is the property of a food product that shows its resistance to breaking due to the applied compressive force.Textural hardness is one of the important physical parameters to be analyzed in determining cake quality.The greater the load value, the harder the material can be assessed [18].Based on the data in Table 4, it shows that the texture hardness value of the cake in the selected treatment S4 (Warumbia brown rice flour modified BAL SBM.4A) Pore Pore Pore Pore is 0.85 (kg/cm2) which is lower than the hardness of the control cake, which is 1.58 (kg/ cm 2 ).This can be influenced by the ability of rice flour to absorb water.BAL SBM.4A modified brown rice flour has good swelling power characteristics with the ability of starch to easily absorb water so that it can provide a soft texture and reduce the level of hardness in cakes.The swelling power value of BAL SBM 4A modified brown rice flour was 10.50 (g/g), and the water content value was 8.06 (%) higher than control flour, was 7.18 (%) [5].This is in line with Manley [9] which states that differences in the percentage of water content are influenced by the amount of starch content in the flour.This can have a positive impact, namely increasing the water holding capacity, which will increase the rate of hydration and reduce the level of hardness of the bread.

Proximate analysis
The T test results of the proximate value of Warumbia brown rice cake include tests for water, ash, fat, protein and carbohydrate content.The proximat test results can be seen in Table 5.

Cake water content
Water content is the percentage of water contained in a food product.The cake moisture content from the S4 treatment (BAL SBM.4A modified brown rice flour) was 19.23 (%wb) while the control cake moisture content was 17.92 (%wb).The cake from the selected treatment had a higher water content than the water content of the control cake.This is because the water content of the basic material used, namely BAL SBM.4A modified brown rice flour, has a higher water content than the water content of unmodified brown rice flour.The fermentation process in brown rice causes a decrease in pH caused by the added activity of LAB and makes the starch granules become soft and expand so that water can be easily absorbed.Acid can disrupt the hydrogen bonds in starch, causing the starch granules to expand more easily.Macromolecules that were previously relatively compact become somewhat porous because they are broken down into shorter polymers with a small mass so that they are somewhat loose and absorb water more easily [18].The increase in water content of modified Warumbia brown rice flour cake still meets the quality

Cake ash content
Ash is an inorganic substance left over from burning organic substances in food.The ash content of a food ingredient shows the amount of minerals contained in the food ingredient [7].The ash content of the cake made from BAL SBM.4A modified brown rice flour was 0.86 (%wb) lower than the ash content of the control brown rice flour cake, which was 0.96 (%wb).The reduction in ash content can be influenced by the fermentation process.Brown rice fermented using microbes can reduce ash content, because minerals are needed by bacteria as electron acceptors in glucose metabolism, enzyme activators, including in the exopolysaccharide polymerization reaction, resulting in a decrease in mineral content during the fermentation process [5].According to Oetami [19], the decrease in minerals occurs because bacteria utilize minerals as a source of nutrition, even in small quantities.The reduction in ash content can also be influenced by the type of material, ashing method, time and temperature used [20].The ash content in the modified Warumbia brown rice flour cake BAL SBM.4A meets the quality requirements of SNI 01-3840-1995, that is a maximum of 3%.

Cake fat content
Fat is one of the nutrients the body needs because it functions to provide energy of 9 kilocalories/gram, dissolves vitamins A, D, E, K and can provide essential fatty acids for the human body.Fat is a good storage unit for energy [18].Based on the data in Table 5, it shows that the fat content of the S4 treatment (modified brown rice flour BAL SBM.4A) increased but was not significant compared to the control treatment.The fat content in the BAL SBM.4A modified brown rice flour cake was 23.90 (%wb) higher than the fat content of the control cake, which was 23.69 (%wb).According to Oetami [19], the increase in fat content in fermented flour still cannot be explained.However, there is the possibility of transformation of carbohydrates into fatty acids [21].Carbohydrates will be converted into glucose, then glucose will be converted into glucose 6-p, which will then be converted into fructose 6-p, then into Acetyl-CoA first.The acetyl-CoA will be converted into free fatty acids through metabolic processes [18].The fat content in the cake products produced is also obtained from the use of other ingredients such as margarine and eggs [22].

Cake protein content
The protein content in the cake made from BAL SBM.4A modified brown rice flour was 9.54 (%wb) higher than the fat content of the control brown rice flour cake, which was 5.28 (%wb).The increase in cake protein content can be influenced by the main ingredient used, namely modified Warumbia brown rice flour BAL SBM.4A.The protein content of BAL SBM.4A modified brown rice flour is higher, namely 6.75 (%db) compared to control rice flour, namely 4.75 (%db).The increase in soluble protein content of modified Warumbia brown rice flour could be caused by the breakdown of complex proteins into simpler proteins that are more easily soluble in water.The brown rice fermentation process increases the soluble protein content in modified Warumbia brown rice flour due to the activity of the protease enzyme produced by the LAB isolate SBM.4A used [5].

Cake carbohydrate content
The results showed that the carbohydrate content of the cake made from modified Warumbia brown rice flour BAL SBM.4A was 46.47 (%wb) lower than the carbohydrate content of the control cake of 52.15 (%wb).The reduction in carbohydrate levels can be influenced by the fermentation process of Warumbia brown rice using BAL SBM.4A.When the fermentation process takes place, the starch components are broken down into simpler ones carried out by amylase enzymes and microorganisms in an effort to obtain energy for their growth and activities.During the fermentation process, LAB will then break down glucose to produce organic acids such as lactic and acetic acid [8,16].

Conclusion
Based on the research results, it can be concluded that the effect of using Warumbia brown rice flour modified with crude enzyme amylase, BAL SBM.3D and BAL SBM.4A has a real effect on the hedonic organoleptic assessment of color and aroma and has a very real effect on the taste and texture of the cake.Meanwhile, in the organoleptic assessment, the descriptive scale of Warumbia brown rice flour cake had a very significant effect on color, aroma, taste and texture.The selected treatment preferred by the panelists was treatment with modified brown rice flour using Lactic Acid Bacteria (LAB) SBM.4A (S4).The use of modified Warumbia brown rice flour BAL SBM.4A (S4) as the selected treatment had a significant difference in the characteristics of cake expansion, porosity and density of camba cake.The proximate content which includes water content, ash content and fat content meets the cake quality requirements according to SNI 01-3840-1995.In general, the research results show an increase in the physical, chemical and organoleptic characteristics of cakes derived from modified brown rice flour compared to those without any modification process.

Fig. 2 .
Fig. 2. Appearance of the poosity of brown rice cake by observation in a stereo microscope and observation with direct documentation Description: a. Porosity of brown rice cake without modification with direct documentation b.Porosity of brown rice cake with BAL SBM.4A modification with direct documentation c.Porosity of brown rice cake without modification with stereo microscope observation d.Porosity of brown rice cake with modified BAL SBM.4A with stereo microscope observation

Table 1 .
Recapitulation of analysis of variance of the effect of adding modified brown rice flour on the organoleptic characteristics of cake products

Table 2 .
Results of hedonic organoleptic assessment of color, aroma, taste and texture of Warumbia Like Note: Numbers followed by different letters in the same column differ significantly in degree 95% confidence.Symbols: S1 (unmodified brown rice flour) S2 (modified brown rice flour with crude amylase enzyme), S3 (modified brown rice flour SBM.3D), S4 (modified brown rice flour SBM.4A)

Table 3 .
Results of descriptive organoleptic assessment of color, aroma, taste and texture of ab Soft Note: Numbers followed by different letters in the same column differ significantly in degree 95% confidence.Symbols: S1 (brown rice flour without modification), S2 (brown rice flour modified by crude amylase enzyme), S3 (modified brown rice flour SBM.3D), S4 (modified brown rice flour SBM.4A)

Table 4 .
Physical T test results of selected modified Warumbia brown rice cake

Table 5 .
Results of proximate assessment of control treatment and selected treatment cake products