The Physicochemical of Bread Additional Cascara Flour and Its Correlation

. Cascara, a coffee industry by-product, has the potential to be beneficial to health due to its fiber and bioactive components. Its effects when added to bread are not clarified. Thus, this study aimed to explore the addition of cascara flour and to correlate the physical and chemical properties of the substitutions. The cascara flour was used as an additional ingredient in bread formulas at three levels (C1=1%, C2=2%, and C3=3%, w/w). The addition of cascara flour increased ash content, but the protein content of the bread did not show significant differences (15.03  0.35 to 15.94  0.73% db). The lightness of the bread decreased when the cascara flour was added. Hardness and chewiness increased with the addition of the cascara flour, with C3 having the highest values (369.45  2.88 N and 0.68  0.03, severally). However, loaf volume and baking expansion showed no significant differences among the treatments, measuring 1462.02  11.32-1550.42  55.73 cm3 and 5.44  0.37-5.68  0.21 %, respectively. Sensory evaluation indicated that the panelists preferred the bread with cascara flour, with C1 being the most preferred overall. The PCA revealed a positive correlation with hardness, gumminess, a value, volume loaf, and chewiness, while the HCA showed that C2 and C3 were in the same cluster.


Introduction
Indonesia has a significant history of coffee production and continues to be recognized as one of the five coffee producers globally.The country primarily cultivated two main varieties, namely Arabica and Robusta.Based on the coffee process, there are two methods, namely dry method and wet method.The dry method, also known as natural method, is carried out by directly drying the coffee cherries, while the wet method removing or eliminating its cherry skin [1].Consequently, the cherry skin becomes one of the by-products generated during coffee production.The potential functional value of this waste has been extensively explored, and its utilization has gained increasing importance.
The word "cascara" comes from Latin language meaning "skin" so that the coffee cherry skin from wet process is called cascara.The cascara had been analysed and found to contain 1.48 % GA of total phenolics, 28% total fiber, 18% solid dietary fiber, 10% insoluble dietary fiber, and 1.53 mmol of Trolox/100 g of antioxidant activity [2].Therefore, the study of cascara has been done due to its bioactive compounds such as fermented cascara [3,5].However, the utilization of cascara in food products has predominantly been limited to its use as tea rather than as a substitute for food ingredients.
Bread is one of staple food consumed in the world.It is a food produced traditionally from wheat, and its development often involves adding functional ingredients.Fortification with functional ingredients in bread is regarded creating health-enhancing products, particularly due to the fact that bread typically contains low phenolic content and fiber [6,7].Therefore, various studies have done involving the addition of functional components like antioxidants and fiber, such as [6,9].Moreover cascara, which has been proven to contain antioxidants and fiber, has the opportunity investigate the alteration in its properties following the addition of cascara, particularly focusing on changes in physicochemical and sensory attributes.Hence, understanding the change in physical characteristics during this development is crucial.Additionally, it is important to examine the correlation between the physical and chemical properties of the substitution ingredients.Thus, the aims of this research were to explore bread with additional cascara flour and to correlate the physical and chemical properties of the substitution.

Cascara flour preparation
The cascara was derived from the waste generated during the wet processing of coffee beans.The cascara underwent a drying process using a cabinet drying at 50 o C for 12 h.Following, the dried cascara was sized (Philips HR2115/00, Dutch) and sieved (a mesh with a size of 60).

Preparation of bread additional cascara flour
The preparation of bread was carried out followed the method described by Machado and Thys [10], with some modifications to the formulas.The specific formulas used in this study can be found in Table 1.A mixture consisting of wheat flour, cascara flour, sugar, skim milk, improver, and salt was prepared using a mixer (Philips HR1530/80, Dutch).The dough was proofed for 60 mins at 25 o C; after that, it was mixed again, and it was proofed (second proofed) for 20 mins at 25 o C, after that, the dough was baked for 10 mins at 220 o C (GTK010022, China).

Chemical characterization
The chemical characterizations done on the bread were moisture, ash, fat, and carbohydrate by difference, and those methods were conducted by AOAC [11].The protein was determined using the Dumas combusting method (DuMAster Buchi D-480, Switzerland).

Physical characterization
The physical characterizations of the bread were its texture, color, baking expansion, and volume loaf.The texture profile was carried out using a texture analyzer (TA-XT Plus, Stable Micro System, UK), and it was the pre-speeds, the test-speed, and the post-test speed, 2 mm/s, 1 mm/s, and 2mm/s, in order range [12].All treatments were sliced into cubes measuring 1 cmx 1 cmx 1 cm and then inserted into a plate, which was pressed using a cylindrical probe (P36/R).The color was measured using a colorimeter (3nh colorimeter, China).The baking expansion and specific loaf volume were done according to Diedericks and Jideani, respectively [13].

Sensory evaluation
The sensory evaluation of bread was performed by an untrained panellist, who scored preferences (hedonic test) of the samples.On the evaluation day, the bread loaves were sliced into 1 cm at room temperature.A group of 37 untrained participants (57% male, age 10-41) assessed the sensory attributes, including color, texture, flavour, and overalls.The score ranged from 1 (dislike) to 7 (very much like) [14].

Statistical analysis
The statistical analysis was calculated using one-way ANOVA (IBM) with a significance level of p < 0.05.The analysis of whether there was a significant effect was continued using the Duncan Multiple Range Test.The principal component analysis (PCA) and hierarchical cluster analysis (HCA) of the bread were performed using the R program. ,

Chemical characterization
The chemical analysis results of the bread with additional cascara flour was presented in Table 2.The values of moisture, fat, protein, and carbohydrate content of the treatments did not show any significant differences.Based on the proximate value, the moisture content of the sample (37.580.28-39.660.22 % db) was similar to the other bread studies, such as quinoa flour bread and moringa leaves bread.However, there was a significant difference in the ash content, where the addition of cascara flour resulted in a higher ash content compared to the control (C0).This previous research by Utami, et.el., [15] supported that ash content indicated presence of minerals, and the ash content of it was 4.91%.The ash content of the treatments was range from 1.590.00 to 1.640.00%(db.), moreover, the ash contents were higher than the ash content of bread made with additional quinoa flour (0.75-0.82%) [16].The protein content of the bread samples ranged from 15.030.35 to 15.940.36%.According to Table 2, the protein content of the sample was not significantly different.The fat content of the treatment was comparatively higher (9.840.16-10.600.19%).This result was not in line with the previous study by Rios,et.al. [17] about gluten free from isolate cascara dietary fiber, where the fat was not significantly different but the protein was.

Physical characterization
The physical analysis of cascara bread loaf was presented in Table 3 which included parameters such as texture, color, volume expansion, and baking expansion.The values for volume expansion and baking explanation of the bread loaf did not significantly differ based on the addition of cascara flour, so indicates that cascara flour does not affect the dough's expansion.
Hardness, gumminess, and chewiness increased, while springiness, cohesiveness, and resilience decreased as the concentration of cascara flours increased.The increase in bread hardness as the concentration of cascara flour increases is likely due to the fiber content and phenolic compounds in cascara flour.Fiber content in bread can cause damage to the gluten structure, which affects the crumb structure of the bread [18].The cascara had total dietary fiber of 47.441.85%,insoluble dietary fiber of 31.321.51%,and soluble dietary fiber of 16.121.15%, respectively [19,20].The content of phenolic compounds in cascara flour can interfere with enzymatic and yeast activity in the bread-making process, which results in poor gas strength and unbalanced maltose in the dough [21,23].These results are in line with previous research conducted by Mildner Increasing the concentration of cascara flour resulted in the brightness and b-value of the bread decreasing, while the a-value increased significantly.A picture of the bread (Figure 1) supported this observation.The dark color of the bread is caused by the Maillard reaction, or caramelization, during the baking process.In addition, the color pigments contained in cascara, such as anthocyanins and carotenoids, also affect the color of the final product.Pycia and Ivanišová [19] stated that components that have carotenoids and flavonoids will form the color of the product.In addition, cascara has a polyphenol content of 4.9±0.5 mg GEA/g DM and total phenolic acid contain of 283±12.0mg GEA/L [18].The results in this study show the same trend as previous research conducted by Rios et al (2020) [20], namely that increasing the concentration of isolated coffee cascara dietary fiber in gluten-free bread decreases the lightness value and increases the a value.
The specific loaf volume and baking expansion (Table 3) were not significantly different.The volume loaf ranged from 1462.0211.32 to 1550.4255.73cm 3 , while backing expansion was 5.440.37 to 5.680.21%.Even though both specific loaf volume and baking expansion were not different, the value of baking expansion decreased.This result indicated that the addition of cascara flour had little effect on the expansion of bread.

Sensory evaluation
The sensory evaluation of cascara bread was carried out by 37 untrained panelists, and the result was presented in Table 4. Increasing the concentration of cascara flours significantly decreased all sensory assessment parameters, namely color, taste, texture, and overall.The panelists' assessment of the color parameter decreased with the addition of cascara flours because they did not like the appearance of brown or dark bread.Taste acceptance: there may be a decrease in the score because the addition of cascara flour gives a slight bitter taste to the bread.In cascara, there are interactions between compounds such as caffeine, chlorogenic acid, and trigonelline, which are responsible for the bitter taste [25] (Riandani et al. 2022).As for the texture parameter, the assessment decreased because the more the concentration of cascara flours increased, the harder the texture (as shown in the texture analysis results in Table 4).Panelists may prefer the texture of bread to be soft and not hard.the total PC variance.The PCA was done to describe the relationship between the variables.The sensory attributes (color, texture, taste, and overall) along with L value (lightness), resilience, springless, and cohesiveness showed consistent patterns that were within same direction, and there was a positive correlation among these parameters.Although there is no correlation observed with The sensory attributes (colour, texture, taste, and overall) along with the L value (lightness), resilience, springless, and cohesiveness, showed a positive correlation among chewiness, gumminess, hardness, volume loaf, and a-value.Pycia and Ivanišová [19] reported that the higher the hardness, gumminess, and chewiness values of the bread, the lower its volume, but this result performed that the volume of the loaf was in line with hardness, gumminess, and chewiness values.Adamczyk et.al [26] found that adding chia seed to bread dough weakens the bread due to its lower volume.Either loaf volume or baking expansion was not different than the control; it indicated that the highest concentration (3%) of additional cascara flour was still able to maintain its volume.The interaction between the physicochemical properties of bread and additional cascara flours is performed in Figure 4, as well as treatment and variable clustering based on parameter similarity.Bread additional 2% (C2) and 3% (C3) of cascara flours were grouped together, with the lowest levels in color profile (yellowness and lightness), texture profile (resilience and cohesiveness), and sensory evaluation parameter (taste, color, texture, and overall).Bread without the addition of cascara flour (C0) and bread with an additional 1% (C1) demonstrated a tendency to have a negative association with C2 and C3 in some parameters.The C0 had the highest texture profile (resilience, springiness, cohesiveness), protein, ash, moisture content, baking explanation, yellowness value, lightness value, sensory evaluation parameter (color, taste, overall, and texture).Furthermore, C1 had the highest level of carbohydrate, fat, texture profile (springiness, resilience, and cohesiveness), and sensory evaluation parameters (overall and texture).

Conclusion
Additional cascara flour in bread has an impact on its physicochemical.The bread treatments became darker with increasing concentration, as well as their hardness, gumminess, and chewiness.However, the sensory panellists generally liked the bread with the additional of cascara flour.According to PCA, the bread displayed patterns in sensory attributes (color, texture, taste, and overall), as well as L-value (lightness), resilience, springiness, and cohesiveness, all of which showed a positive correlation among these factors.The HCA analysis revealed that C2 and C3 exhibited similar trends and were categorized in the same group.

Table 1 .
Formulas of bread additional of cascara flours.

Table 2 .
Proximate composition of bread additional cascara flours.

Table 3 .
Physicochemical properties of bread additional cascara flours.Means of the same column in the same superscripts are not significantly different (p<0.05)

Table 4 .
Sensory evaluation of bread additional cascara flours.