The Effect of Hydrochloric Acid (HCL) Concentration on the Quality

of Gourami Bone Gelatin (Ospheronemus Gouramy Lac)

Anggita Rahmi Hafsari

, Diah Rosmiati

, Dindin Jamaludiin

Departement of Biology, Faculty of Science and Technology State Islamic University (UIN) Sunan Gunung Djati Bandung,

JL.AH. Nasution NO 105 Bandung, 40614, Indonesia

Department of Islamic Education and Teaching, faculty of Teaching and Education State Islamic University (UIN) Sunan

Gunung Djati Bandung JL.AH. Nasution NO 105 Bandung, 4061, Indonesia

Keywords: Gelatin, Fish Bone, Halal Gelatin

Abstract: Gelatin is commonly made of the skin and bones of cattles or pigs. This causes problems in the society both

in terms of the halal status and health. Fish bone (Osphronemus gouramy Lac) can be used for producing

gelatin because it contains collagen protein. The purpose of this study was to produce good gelatin with

different concentrations and to identify the physical characteristics of gelatin from the bones of gouramy fish

at several concentrations. The treatment performed in this study used HCl was used with 48 hours immersion

period and concentration of 1% - 5%. The value of rendement in this study ranged from 8.05% - 12.44%, the

viscosity value ranged from 4.7 to 6.1 cP, the gel strength ranged from 71.90 to 90.61 bloom, the water content

ranged from 9% - 12%, the grain ranged from 2.18% - 3.78%, pH levels ranged from 4.64% - 4.85% and the

protein content ranged from 59.68% - 70.24%. Based on these results, it can be concluded that the different

concentrations of acids significantly affect the value of gelatin produced. The best concentration is at 5%. At

this concentration, the gelatin produced has the best physical and chemical properties compared to those

produced with other concentrations.

1 INTRODUCTION

Gelatin is derived proteins from collagen that in

denaturing because of termo-hidrolisis and to

transform termo-reversible between sol and gel (Cho,

2004). Gelatin is a protein conversion is soluble in

water (Sobral, 2001).

Besides food industries, gelatin is also used in

non-food industries such as pharmaceutical industry,

photography, cosmetics, and paper industries. Gelatin

can be used in the forms of capsules, tablets and

pastilles, gelatin sponge, surgical powder, medical

research, plasma expander, and microencapsulation

in the pharmaceutical field.

Gelatin available in the market is mostly made

from the bones of pigs or other mammals such as

cows. In the teaching of Islam, gelatin from pigs is

considered haram (forbidden to consume). This

relates to the Islamic Shari'a law, which requires its

followers to consume only halal food. On the other

hand, the consumption of beef gelatin is often

worrying as cattles are often infected by diseases such

as anthrax and mad cow. In addition, often, in the

process of slaughtering, the name of Allah was not

mentioned and the cut was not made on the jugular

vein of cows, making the beef unlawful. The Quran

describes the prohibition of eating unclean foods, as

follows: Prohibited to you are dead animals, blood,

the flesh of swine, and that which has been dedicated

to other than Allah, and [those animals] killed by

strangling or by a violent blow or by a head-long fall

or by the goring of horns, and those from which a wild

animal has eaten, except what you [are able to]

slaughter [before its death], and those which are

sacrificed on stone altars, and [prohibited is] that you

seek decision through divining arrows. That is grave

disobedience. (Al-Maidah verse: 3).The importance

of halal foods is regulated in Islam as stated in the

Qur'an: "O mankind, eat from whatever is on earth

[that is] lawful and good and do not follow the

footsteps of Satan. Indeed, he is to you a clear

enemy." (Al-Baqarah 168). Besides, Rasulullah

PBUH also said: "Whoever takes a bite of forbidden

goods, then the prayer will not be accepted for forty

days" (HR. Abu Daud).

Rahmi Hafsari, A., Rosmiati, D. and Jamaludin, D.

The Effect of Hydrochloric Acid (HCL) Concentration on the Quality of Gourami Bone Gelatin (Ospheronemus Gouramy Lac).

DOI: 10.5220/0009947329832989

In Proceedings of the 1st International Conference on Recent Innovations (ICRI 2018), pages 2983-2989

ISBN: 978-989-758-458-9

2983

Therefore, obtaining alternative raw materials

for producing halal gelatin is necessary. Gourami

bones are one of the materials which can be used to

produce halal gelatin. Further, gelatin from fish bones

is safer in terms of health because it is not made from

infected materials that can affect the health of

consumers. So, it is expected that the gelatin has a

high quality and meets the standards of commercial

gelatin.

The purpose of this study was to determine the

highest concentration of HCl to generate the best

gelatin with different concentrations and to determine

the effect of HCl concentration on the physical and

chemical characteristics of Gourami bone gelatin.

2 MATERIALS AND METHODS

2.1 Equipments

The equipment used in this study is divided into two:

the equipment used in the manufacture of gelatin is an

analytical balance, beaker, small spoons, measuring

cups, glasses, water bath, an evaporator, a pH meter,

viscometer, Kjeldhal pumpkin.

2.2 Materials

The raw materials used are Gourami bon dry waste as

much as 2 kg, 6 M HC1 distilled water, filter paper

and aluminum foil

2.3 Experimental Design

This study is divided into two phases. The first phase

of the preliminary test, which is the process of making

gelatin from the bones of Gourami (Ospheronemus

Gourami) with a concentration of 2%, 4%, 6%, 8%,

10% and analyzing physical properties that yield. The

second stage of research the manufacture of gelatin,

namely the manufacture of gelatin concentrations that

are the 1%, 2%, 3%, 4%, after the gelatin was chosen

to analyze physical and chemical properties of gelatin

that is yield, viscosity, gel strength, analysis of the

degree of acidity (pH ), moisture content, ash content,

and protein.

2.4 Research Stages

2.4.1 Gelatin Extraction

Bone degreasing or boiled for 20 minutes at 70 ° C

with bone and distilled water ratio 1: 2 (b: v) and then

dried in the sun until bone dry. Degreasing the bones

that have been soaked in a solution of HCI at a

concentration of 1%, 2%, 3%, 4% and 5% for 24

hours (treatment A). The bones that have been soaked

in an acid solution is called ossein and separated and

then filtered. Ossein then neutralized with

water. Ossein the neutral buffer is inserted into the

glass beaker and add distilled water, ossein

comparison with distilled water is 1: 2 (w / w). After

it is extracted with a water bath at a temperature of 90

° C for 7 hours. Then filtered through Whatman filter

paper No. 40. Distillate concentrated by

evaporator. Gelatin solution obtained was still in a

state of liquid. The gelatin solution should be

concentrated. Concentration is done with the

evaporator, until a concentration to 25-30%, the

concentration temperature is 800C, while the time it

takes ± 5 hours (Handoko et al, 2011).

2.5 Research Analysis

2.5.1 Rendemen

Randemen obtained from the weight ratio of dry flour

weight gelatin produced with fresh ingredients (the

bone that has been washed). by AOAC, 1995:

Rendemen =





× 100%

2.5.2 Gel Strength

Gel strength is done objectively by using the tool

Rheoner RE3305. The level of gel strength expressed

in units gf/cm2, which means the amount of

compressive force to break up the deformation of the

product. (British Standard 757, 1975).

2.5.3 Viscosity

The water content of the gelatin is determined by

providing the chemicals as much as 75-100 ml in the

samples estimated to contain as much as 2-5 ml water,

then heated to boiling for 1 hour. Water vapor and

chemicals are condensed and collected in the

reservoir tube. Tools used as a container for include

Strak tube-Dean and Sterling-Bidwell (Nancy, 2013).

%water content =





100

2.5.4 Ash Content

The ash content is determined by weighing the

sample ± 2 grams ago, then put into porcelain dish

until it is heated in a charcoal bath. Samples were

evaporated water is put into the furnace temperature

to 600 0C. The evaporation process until all material

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changes color to gray, then the sample is weighed

(AOAC, 1995).

% Ash Content =





x 100%

2.5.5 Acidity (pH)

A total of 0.2 gram sample is weighed and dispersed

into 20 ml of distilled water at a temperature of 80 °

C. The samples were homogenized with a magnetic

stirrer, and then measured the degree of acidity at

room temperature with a pH meter (British Standard

757, 1975)

2.5.6 Protein Level

A total of ± 0.25 gram dry sample, placed in a 100 ml

Kjeldahl flask and added 0.25 grams of selenium and

3 ml of concentrated H2SO4. Then proceed with the

process for 1 hour until a clear solution. Once cool

add 50 ml of distilled water and 20 ml of 40% NaOH,

and then distilled. Distilled accommodated in a

Erlenmeyer flask containing a mixture of 10 ml of

H3BO3 2% and 2 drops of indicator Brom Crsol

Green Methyl Red pink. Once the volume of

reservoirs (distillate) to 10 ml and the bluish-green,

distillation was stopped and distilled titrated with

0.0235 N HCl until pink. The same treatment was

also carried out on the blank. With this method

obtained the total nitrogen content calculated using

the formula (AOAC, 1995):

% Protein Level =







..



2.6 Data Analysis

Data were analyzed with SPSS 20.0 by ANOVA. If

the results of the analysis significantly different then

tested further using Duncan (Gaspersz 1994).

3 RESULTS AND DISCUSSIONS

3.1 Analysis of Physical Properties of

Gelatin

3.1.1 Rendemen

Based on Figure.1 The yield values obtained in

gelatin by treatment with HCl 5%, ie 12.44%, while

the value of the smallest yield generated 1% HCl

concentration of 8.05%. According to Mulyani et al

(2013), HCl has a bigger and stronger ability to

degrade CaCO3 minerals of calcium is in the bones

of Gourami compared with a base. Conversion of

collagen into gelatin can be affected by temperature,

heating time, and pH. In attachment.5 the values

ranged on average from 8.16 to 12.44%. The size of

the yield value is influenced by the concentration of

HCl is different. The yield shows the effectiveness of

the methods used in a study, especially about

optimalitasnya in producing a product. The higher the

yield value indicates the treatment is applied to the

research more effective (Miwada and Simpen, 2007)

Figure 1 The value of bone Gourami rendemen gelatin.

Description: Different letters indicate a significant

difference at a significant level α = 0,05

3.1.2 Viscosity

Viscosity is the power flow of molecules in a solution

either in water, a simple organic liquid and an

aqueous suspension (Fever, 1989). The average value

of Gourami viscosity bone gelatin is 4.7 to 6.1 cP

(Figure.2). This research viscosity grades according

to standards set by GMIA in 2012 is between 1.5 to

7.5 cP. According to Setiawati (2009), viscosity or

viscosity of the gelatin solution is closely related to

the water content of dry gelatin. The lower the water

content of dry gelatin then its ability to bind water (to

form a gel) will be higher. The more the amount of

water bound by the gelatin will become increasingly

viscous gel, which directly affect the higher the

viscosity measured value.

Figure 2 Viscosity Values Gourami Bone Gelatin.

Description: Different letters indicate a significant

difference at a significant level α = 0.05

12345

Rendemen …

HCl Concentratio

12345

Viscosity cP

HCl Concentration (%)

The Effect of Hydrochloric Acid (HCL) Concentration on the Quality of Gourami Bone Gelatin (Ospheronemus Gouramy Lac)

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3.1.3 Gel Strength

Gel strength is important in knowing the best

determination, because one of the important

properties of gelatin is able to transform the liquid

into a gel which is reversible. Ability is what causes

the gelatin very wide use, both in the field of food and

non-food (Harris, 2008).

Based on advanced test Duncan showed that

the treatment with using a 5% concentration showed

the highest gel strength, which amounted to 90.61

bloom, while for the results of the gel strength

smallest one is at a concentration of 1% at 71.90

bloom (Figure.3). The use of different concentrations

significant effect, this is caused by collagen with acid

hydrolysis process went quite well with increasing

concentrations and the heating process that would

damage the gelatin to form a gel structure. According

Astawan (2002), high gel strength associated with

long-chain amino acids, which long chains of amino

acids that will produce a large gel strength. Optimal

hydrolysis process will result in a long chain of amino

acids, and at the time of conversion of collagen into

gelatin will produce a high gel strength.

Figure 3: Value of Gelatin Gourami Bone Strengt.

Description: different letters indicate a significant

difference at a significant level α = 0.05

3.2 Gelatin Chemical Properties

Analysis

3.2.1 Water Content

Water is an essential ingredients in a food. Water can

be either intracellular or extracellular components of

a product (deMan1989). Water in food ingredients

will determine the acceptability, freshness and

durability of the material. Water can also affect the

appearance, texture, taste, and quality of foodstuffs

(Winarno, 1992).

Differences in water content varying

allegedly due to the use of materials that are not

evenly distributed between the hard bone and

cartilage in each treatment thus affecting the results

of the water content of the gelatin bones of Gourami,

besides the difference in the water content of the

gelatin is affected by the drying process each sempel

for every sempel the concentration difference has a

drying time is different.The statement was supported

by Rev. et al (2013) that for every sample requires a

different time to be a dry sample.

The average value of the water content of

Gourami bone gelatin ranging between 9% -

12%. The highest water content is at 5% HCl

concentration of 12%, while the smallest water

content is at a concentration of 3% by 9%

(Figure.4). Differences in water content was

allegedly influenced by different raw materials in

each sample. Water content of the fifth HCl

concentration of gelatin still meet the quality

standards of ISO No. 53 of 1995 which is up to 16%

and the standard of JECFA in 2003 a maximum of

18%.

According to deMan (1997) gelatin moisture

content affects the shelf life of a product, because it is

closely related to metabolic activity that occurred

during the gelatin is stored. The role of water in food

is one of the factors that influence the metabolic

activity such as enzyme activity, microbial activity

and chemical activity, namely the occurrence of

rancidity and non-enzymatic reactions giving rise to

changes in organoleptic properties and quality values.

Figure 4: Water content Gelatin Gourami Bone.

Description: Different letters indicate a significant

difference at a significant level α = 0.05

3.2.2 Ash Content

Ash is an organic substance that is not burned in the

combustion process of organic substances. These

substances include sodium, chlorine, calcium,

phosphorus, magnesium, and sulfur (Winarno

1992). Ash content value of foodstuffs showed a large

amount of minerals contained in the food of a

substance (Apriyantono 1989).

cde

100

12345

Gel Strength

(bloom)

HCl Concentration (%)

12345

Waterr Content (%)

HCl Concentration (%)

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Figure 5: Levels of Ash Gelatin Gourami Bone .

Description: Different letters indicate a significant

difference at a significant lvel α = 0.05

Duncan advanced test showed that the concentration

of HCl gives a significantly different effect (P ≤ 0.05)

with a concentration of 3%, 4% and 5%, but not

significantly different (P ≥ 0.05) with a concentration

of 1% and 2% (Figure.5). Decreased calcium in the

ossein is what causes the reduction of the value of its

own ash content. Revelation et al (2013) states that

the use of different acid concentrations have a

significant influence on the ash content of

gelatin. Marked with the rate of decline of the gelatin

ash content along with the increasing concentration of

acid used solvents. Allegedly higher acid

concentrations can dissolve bone mineral in large

quantities by the leaching process. According to

Mulyani et al (2013), the use of HCl in the immersion

process will react with the calcium phosphate

bone. This will produce a soluble calcium salt and

bones become soft, because HCl has bigger and

stronger ability to degrade CaCO3 minerals of

calcium is in the bones of Gourami compared with the

use of bases

Value ash content contained in a product

indicates the level of purity of the product.The level

of purity is affected by the composition and mineral

content. Abu contained in gelatin derived from salts

or minerals in the bones of fish used (Ratri, 1998).

3.2.3 Acidity (pH)

The pH value of the degree of acidity gelatin is gelatin

which is one of the important parameters in quality

standards gelatin. pH gelatin based gelatin quality in

general is expected to approach a neutral pH (Heidi,

2006).

Figure 6 pH of Gelatin Bone Gourami . Description:

Different letters indicate significant differences at the level

of α = 0.05

In this study it was found that the higher the

concentration of HCl pH value lower. The low pH

value is due to the use of strong acid HCl. Allegedly

in the event of collagen development time soaking

with HCl, much residual unreacted HCl absorbed in

the collagen which expands and caught in the

collagen fibril network, making it difficult neutralized

when washing that eventually brought current

extraction processes that affect the level of acidity. In

Appendix 5 the average pH value in Gourami bone

gelatin ranged from 4.64 to 4.85%. The highest pH

value is at a concentration of 1% by 4.85%

(Figure.6). This is because the higher the

concentration is used it will be increasingly

concentrated acid and also the acid ossein which is

bound to be more and more. While the lowest value

contained at 5% concentration of 4.65%. Nurimala

(2004), stating Low pH values in this study because

it is still carrying over of residual HCl on fish bones

and carried the time of extraction, thus affecting the

value of acidity in the resulting gelatin. The pH value

of Gourami bone gelatin in the amount of 4.64 to

4.85%. According Hinterwaldner (1977) in Nofri et

al (2014) gelatin pH value relates to the process

used. Acid process tends to produce low pH, whereas

the alkaline process will have a tendency to produce

a high pH. Gelatin with a neutral pH is more preferred

that the neutralization process plays an important role

in the manufacture of gelatin.

3.2.4 Protein Level

Proteins are polymers of about 21 different amino

acids and peptides associated with the bond. Proteins

in the gelatin included in the group Scleroprotein

simple protein, because gelatin is obtained from the

hydrolysis of collagen. (De Man, 1989).

12345

Ash Content (%)

HCl Concentration (%)

4.4

4.6

4.8

12345

pH value (%)

HCl Concentration (%)

The Effect of Hydrochloric Acid (HCL) Concentration on the Quality of Gourami Bone Gelatin (Ospheronemus Gouramy Lac)

2987

Figure 7 Levels of Protein Gelatin Bone Gourami.

Description: notation different letters indicate a significant

difference at a significant level α = 0.05

Based on Figure 4.7 the value of the highest levels of

the protein present in a concentration of 5%

amounting to 70.24%, while the value of the lowest

levels of the protein present in a concentration of 1%

at 59.68%. Suspected high acid capable hydrolyze

collagen into gelatin. According to Rusli (2004), the

protein content of the gelatin is affected by the

immersion process of bone. Soaking process resulted

in the termination reaction of hydrogen bonds and the

opening of the coil structure of collagen occurring

optimally so that the amount of protein extracted into

many. Table 4.1 Based on the analysis of physical and

chemical properties of gelatin best results are at

concentrations of 5% with the result that much better

with the other concentration. This proves the higher

the concentration, the better the results of quality

gelatin. The value of physical and chemical

properties a concentration of 5% produces the highest

protein content with other concentrations of 70.24%,

with a yield of 12.44%, a value of 6.1 cP viscosity,

gel strength 90.61 bloom, the water content of 12%,

pH 4.64%, and ash content of 2.18%. According to

Martianingsih and Lukman (2010), the immersion

process using the acid solution will convert collagen

into a form suitable at the time of extraction in the

presence of H + ions from the acid solution with

collagen.

4 CONCLUSION

Acid concentrations varying significantly affect the

resulting gelatin. Based on this research the best

concentration present in concentrations of 5%. At the

concentration of gelatin values obtained with the

physical and chemical properties compared with

other concentrations. Treatment of acid

concentrations varying influence on the physical and

chemical properties of Gourami bone gelatin. The

results of the analysis of physical and chemical

properties showed significantly different results with

commercial gelatin and gelatin laboratory

standards. Based on the analysis of physical

properties that yield value of 8.05 to 12.44%, ranging

between 4.74 to 6.13 cP viscosity and gel strength of

71.90 to 90.61 bloom. As for the chemical analysis

that the ash content ranged from 3.78 to 2.18%, water

content ranging between 10-12%, the pH value

ranging between 4.64 to 4.85% for protein content

ranged from 59.68 to 70 , 24.

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