Study of Pressure Cooker Application in Milkfish Processing

Industry to Increase Productivity and Quality

Sunyoto

, Atiek Zahrulianingdyah

and Indah Anisykurlillah

Department of Mechanical Engineering, Universitas Negeri Semarang, Semarang, Indonesia

Department of Home Econonic, Universitas Negeri Semarang, Semarang, Indonesia

Department of Economic, Universitas Negeri Semarang, Semarang, Indonesia

Keywords: Pressure Cooker, Soft Thorn Milkfish, Productivity, Quality.

Abstract: The purpose of this activity is to develop and implement cooking equipment in the small industry of making

milkfish soft thorn in the city of Semarang. The equipment is to increase productivity and quality. The

development of tools is carried out in several stages, they are designing stage, calculation of strengths, making

tools, testing, refinement of tools, and tool application to figure out if the tool work well. A set of soft thorn

milkfish cooking equipment has been made. It has special operating method as well as several advantages.

Some advantages of this tool are that the tool is more fuel-efficient, it has greater production capacity, and it

yields better quality milkfish which is higher protein content, better texture, and free of damage. In addition,

the use of this new tool can increase the profits of soft thorn milkfish producers.

1 INTRODUCTION

Soft thorn milkfish or better known as bandeng presto

(presto milkfish) is a typical gift of Semarang City,

where the market share of this product is widely open.

It is not only for Central Java people, but also for

people throughout Indonesia and even international

costumers (who were mostly tourists). Bandeng

presto is not only sold in shops or souvenir centers

(Pandanaran Street Semarang) but is also widely sold

in traditional markets.

Milkfish includes milky white hard-fleshed and

fleshy fish. The structure of the meat is solid with

many fine spines between the flesh, especially around

the tail. The nutritional value of milkfish is quite high.

Every 100 grams of milkfish contains 129 kcal of

energy, 20 g of protein, 4.8 g of fat, 150 mg of

phosphorus, 20 mg of calcium, 2 mg of iron, 150 SI

of vitamin A, and 0.05 mg of viamin B. Based on the

nutritional composition then milkfish are clas-sified

as high-protein and low-fat fish (Saparinto, 2006: 11).

Milkfish content, especially Omega 3, is higher

than the content of Omega 3 salmon which is an

imported fish. Milkfish is one type of fish that has a

specific taste, and has been known in Indonesia and

even abroad. According to the research of the

Fisheries Quality Research and Development Center

(1996), milkfish has 14.2% omega-3, it exceeds

omega-3 substance in salmon which is only 2.6%,

tuna fish (0.2%) and sardines or mackerel fish (3.9%)

(http://www.naqsdna.com).

For presto milkfish, other protein factors must

also be considered. The quality of soft thorn milkfish

can be seen from the following five parameters:

Table 1: Soft Thorn Milkfish Quality Criteria.

Parameters

Remarks

Visualisation

the fish is intact and un-broken,

smooth, un-injured, clean, un-

contaminated with outside or strange

matters and there is no deposits of

fat, salt and other impurities.

Color

it has specific color, brilliant, un-

moldy and slimy.

Smell/Odor

It has specific odor such as boiled

fish, savory and fresh fish without a

rancid, sour, stale or rotten odor.

Taste

It should be savory, specific, thorny

milkfish, soft and not too salty, salty

taste evenly distributed, no foreign

flavor.

Texture

Compact, solid, quite dry, not runny,

invisible

Source: Saparinto, 2006: 51.

Sunyoto, ., Zahrulianingdyah, A. and Anisykurlillah, I.

Study of Pressure Cooker Application in Milkﬁsh Processing Industry to Increase Productivity and Quality.

DOI: 10.5220/0009006700770083

In Proceedings of the 7th Engineering Inter national Conference on Education, Concept and Application on Green Technology (EIC 2018), pages 77-83

ISBN: 978-989-758-411-4

Milkfish, that has been processed into soft thorn

milkfish (bandeng presto), will have several values

more; 1) If it is stored, the fish has a long endurance,

2) the thorn becomes soft, it makes easy serving, and

3) the price will increase compared to the previous

original milkfish (Suhaeni, 2007: 12).

Both modern and traditional class-presto milkfish

run by small industries in Semarang City. For

"modern" presto milkfish business owners, there are

almost no significant obstacles. Every day the

turnover is tens of millions of rupiah, and generally

owned by entrepreneurs with large capital and has

been established for decades. On the contrary, most

of the traditional presto milkfish producers by small

businesses (UMKM) in Semarang, the condition is

that good.

In Semarang city, presto milkfish industry is

spread out in 14 districts and 25 villages. Total

investment value reaches IDR 515,200,000, thus the

total production value reaches IDR 907,600,000, with

a total workforce of 141 people (Semarang City

Office of Industry and Trade Data, 2012). One of the

centers of presto milkfish industry in the city of

Semarang is in Krobokan Village, West Semarang

Subdistrict, and currently is a member of the

Community-Based Self-Help Group (KSM) "Soft

Thorn Milkfish". Although their existence has existed

since the 1990s, but the establishment of a business

group in the KSM "Soft Thorn Milkfish" started in

2004, led by Mr. Petrus Sugiyanto.

Presto milkfish which is produced by small

entrepreneurs is cheaper than presto milkfish which is

sold at the center of souvenirs along Pandanaran

Street Semarang. Presto Milkfish should made by

small entrepreneurs in Krobokan and other areas of

Semarang City shoud be more competitive, however,

the reality shows un-satisfying condition. Production

development or business turnover is stagnant, and this

is a problem with many aspects, such as aspects of

production, technology used, product quality,

packaging, marketing management and other aspects

that need to be solved.

The existence and condition of KSM "Soft Thorn

Milkfish" in Krobokan is a representation of small

thorn milkfish businessmen scattered in other sub

district in Semarang and number of dozens of

business units. The number of workers involved in

the presto milkfish manufacturing business is

between 2 to 4 people. Based on the scale, this

business includes home industry (with workers under

4 people). However, seeing its business turnover and

market opportunities, this milkfish processing

business has a long chain and involves a lot of labor

(ranging from fish farmers to marketing personnel) so

that it greatly influences people's economic activities.

Therefore, any solutions to the problems faced by

small-scale milkfish processing entrepreneurs, are

necessary to affect the economic activities of the

people at large stage.

Based on surveys and observations in the field, the

problems faced by presto milkfish small-scale

entrepreneurs can be divided into three aspects, they

are: production, quality, and business management or

marketing where these three aspects are interrelated.

In this paper, the problem is limited to aspects of

production, namely appropriate technology (TTG) for

making presto milkfish.

According to Sonhaji (2012), appropriate

technology is often called intermediate technology

(intermediate technology), because it must be in the

midst of the extreme ends of primitive technology and

advanced technology. This technology must be small-

scale, simpler and cheaper, and easier to implement,

but must be better than primitive technology. In

addition, in the selection of appropriate technology, it

is necessary to pay attention to several criteria,

including: a) technology chosen must be able to meet

real needs, which can be directly utilized and enjoyed

by the local community, b) the technology is initiated,

it gains participation, increases employment

opportunities, and increases the income of the local

community, and d) th technology must be able to

increase productivity, add value and quality of

production, increase the quantity and quality of

human resources, and promote innovation and

creativity of the local community, e) The technology

can optimally improve natural resources, the

equipment should be easily handled and maintained

by the local community.

Based on the above criteria, the development of

presto milkfish cooking equipment that will be

applied in the community includes part of appropriate

technology (TTG). In this activity begins with the

design or design of the TTG. The design is designed

so that the tool can function as expected. As stated by

Hurst (2006: 4), engineering design is all activity to

build and define solutions to problems that cannot be

solved before or in a different way than before.

Engineering designers use the intellectual ability to

apply scientific knowledge and ensure its products

are in line with market needs.

Meanwhile, according to the Presidential

Instruction of the Republic of Indonesia Number 3 of

2001 concerning Guidelines for Implementing and

Developing Appropriate Technology, the definition

of Appropriate Technology is technology that is

appropriate to the needs of the people, it also can

answer community problems, it does not damage the

EIC 2018 - The 7th Engineering International Conference (EIC), Engineering International Conference on Education, Concept and

Application on Green Technology

environment, and can be easily utilized by the

community and generate added value from economic

aspects and environmental aspects.

So far, small businesses still use the technology of

simply making presto milkfish. The tools used in the

form of presto pans are purchased from stores with a

maximum capacity of 5 kg of raw milkfish. To cook

the presto milkfish, it uses an LPG gas stove (a small

portion still uses kerosene) with a cooking time of 3

hours. If you cook 40 kg of milkfish, it takes 8 stoves

or 8 cooking processes. This method is very

inefficient because it is wasteful of fuel, it takes a long

time, and takes a lot of space. In addition, with a small

diameter pan (30 cm) and without a shelf, the milkfish

is damaged and flattened. Therefore, it is necessary to

immediately find a solution to overcome the

problems faced by this milkfish producer.

Figure 1: Conventional Presto Pan: Production Capacity is

5 kg without shelf.

By observing problems faced by presto milkfish

producers, in this study will work on designed and

appropriate technology which is useful for modern

presto milkfish makers. This tool is a development of

presto milkfish maker LTHPC (Low Temperature

High Pressure Cooker) which was previously made

by the implementing team.

Some of the advantages of presto milkfish making

tools that will be applied later are: 1) it has higher

productivity: in one process it is able to cook up to 40

kg of milkfish, while the partner industry can only

cook 5 kg in each pan so they have to cook for about

8 times); 2) it saves time: since the tool only takes 90

to 120 minutes, while the old method takes 3 hours or

180 minutes, obviously it is more efficient; 3) it is fuel

saving (BBM): because the cooking process is faster,

less fuel is needed so the production costs are smaller;

4) it leads to cost-effectiveness: because of high

productivity, faster time, and more economical fuel

economy, production costs decrease and profit

margins increase; 5) it has higher quality: 0% damage

level, no milkfish damaged by bending or flattening,

because the diameter of the presto pan is 55 cm and

in the preparation of milkfish made up of shelves.

2 METHODS

In designing a product, there are several methods,

including the methods of French, Pahl & Beitz, VDI,

and Ullman. Each method has a different phase or

stage. Generally, same stages or phases are almost the

same (Harsokoesoemo, 2004). The stages are: 1)

problem and needs analysis, 2) design of product

concepts, 3) preparation of product technical

specifications, 4) product manufacturing, 5) product

trials, and 6) product improvements.

The implementation team of this activity was

selected from various disciplines to support the

success of the activities. In addition to the support of

human resources (HR), this activity is also supported

by laboratory facilities as well as sufficient work-

shops from the Department of Mechanical

Engineering, Semarang State University.

In this activity presto cooking equipment will be

developed with a design like picture 1. In this presto

cooker there is a temperature control device.

Temperature Controller is connected to a gas flow

regulating valve, which regulates the flame, where if

the desired temperature is reached, the stove flame

will shrink automatically.

Figure 2: Pressure Cooker Design.

Remarks:

1. Presto pan/body tube 14. LPG Gas Stove

2. Tube feet. 15. Tube Holder

3. Cap

4. Locking bolts

5. Thermometer

6. Manometer

7. Safety valve

8. Thermocouple

9. Control panel

Study of Pressure Cooker Application in Milkﬁsh Processing Industry to Increase Productivity and Quality

10. Pole control panel

11. Solenoid valve

12. LPG gas hose.

13. LPG gas cylinders

Conversely, if the temperature drops below what

is desired, then the flame of the stove will enlarge

automatically and the temperature will rise again.

With this system will make it easier for operators and

fuel consumption to be more controlled or more

economical.

After the tool is made according to the design

drawings, the next step is to test the use of the tool.

The purpose of this trial is to test the effectiveness of

the device whether it is in accordance with the desired

goals or not. If there are deficiencies in terms of

construction or workings, the tool can still be refined

before it is actually implemented. In addition, the trial

aims to obtain data as a material for further analysis

so that it has an accountable basis.

3 RESULTS AND DISCUSSIONS

In this activity a set of milkfish presto cooking

utensils has been produced with the following

technical specifications:

Height: 80 cm

Diameter: 55 Cm

Pot Material: Stainless Steel (SS 304)

Pan Thickness: 3 mm

Capacity: 40-50 kg of fresh milkfish

Number of Shelves: 10 Shelves

Fuel: LPG

Cooking time: 1.5 - 2 hours

LPG consumption: 1 - 1.5 kg / process

A set of soft thorn milkfish cooking equipment

consists of: (1) presto pans / tubes, (2) milkfish

shelves, (3) temperature control, (4) LPG stoves, and

(5) LPG gas cylinders. Inside the tube is designed a

special shelf several layers so that milkfish are not

flattened. This is not in the previous cooking tools, so

most milkfish produced by traditional milkfish

entrepreneurs are flat and bent.

Figure 3: Pressure Cooker with New Design.

Figure 4: The Milkfish are layered in the shelves.

The soft thorn milkfish cooking equipment

produced is equipped with temperature control which

aims to regulate the high and low heating

temperatures that correlate with fuel consumption.

Temperature Controller is connected to a gas flow

regulating valve, which regulates the flame, where if

the desired temperature is reached, the stove flame

will shrink automatically (not to death). Conversely,

if the temperature drops below what is desired, then

the flame of the stove will enlarge automatically and

the temperature will rise again. With this system will

make it easier for operators / cookers and fuel

consumption to be more controlled / more

economical.

After the design of the finished equipment, the

next step is to test the use of tools to make presto

milkfish. Trials involve experienced presto milkfish

entrepreneurs in the hope of assessing the quality of

milkfish produced more valid.

EIC 2018 - The 7th Engineering International Conference (EIC), Engineering International Conference on Education, Concept and

Application on Green Technology

Table 2: The Result of Trial I in Making Soft Thorn

Milkfish.

Temperature

Pressur

Cooking

Duration

LPG

Consu

mption

Results

105-110º C

1,5 atm

120 min

1 kg

Soft thorn

Milkfish

good

texture,

tekstur

bagus,

unflattened

undamage.

Based on the first trial that has been done, the

results can be said to be good and satisfying. This is

according to Mr. Petrus Sugiyanto as a milkfish

entrepreneur who has decades of experience.

According to him, who also uses milkfish presto

LTHPC, this result is better than previously thought.

After the implementation team tested the tool and

succeeded, the next step was to conduct a second trial

as well as to socialize the use of tools to KSM

members "Soft Thornfish Milkfish". In this activity

the participants were explained about the functions

and benefits of the tools, the advantages they have, as

well as the operational technical use of the tools. In

this activity, the implementation team carried out the

practice of making milkfish from the beginning to the

end, starting from the preparation of raw materials,

arranging milkfish, operating the equipment, until the

milkfish was well-cooked.

The results of the milkfish manufacturing in

the second trial can be seen in table 3 below.

Table 3: The Result of Trial II in Making Soft Thorn

Milkfish.

Temperatu

Pressure

Cooking

Duration

LPG

Consumtio

Result

100º C

1,7 atm

120 min

1,8 kg

Soft

thorn

Milkfish,

good

texture,

undamag

ed.

Based on the trial results of making soft thorn

milkfish above, the quality from both trials were

good. Both methods yielded soft thorn milkfish, good

texture, and unbroken fish. Yet, in both trials, the

consumption of LPG has different in amount. The

second trial needed more fuel. It was because there

was a difference in temperature control setting. In the

first trial, the temperature setting was done twice. At

the first stage, the temperature was set to a maximum

of 110ºC. After heating reached a temperature of

110ºC, the temperature control was set again, then the

temperature was set to a maximum of 100ºC. This

was done based on the assumption that after the fire

stove decreased, the temperature in the pan would

drop. In order to reduce the temperature that has no

effect to the temperature control, or lessen stove

flame (which can increase LPG consumption), the

temperature control setting should have been made

lower, for instance 10º C up to 100º C.

After it reaches the temperature of 110º C, the fire

decreases and the temperature drops to 105ºC.

However, because the temperature drop is still above

the set temperature (100º C), the stove flame remains

small, and the consumption of LPG fuel remains low.

Different things occur during the second trial

where the temperature setting is only done once, for

instance, the temperature is set to a maximum of

100ºC. As a result, when the flame of the stove

decreases, the temperature drops below 100º C.

Because the temperature below is set (100º C),

temperature control works , the gas flow regulating

valve opens so that the flame of the stove enlarges

again and of course it requires greater consumption of

LPG gas as well. When the flame increases, the

temperature rises above 100º C (101º C) and the fire

shrinks again. But this does not last long and the stove

burns again. This small and enlarged flame condition

occurs repeatedly to maintain the temperature at

100ºC. The effect is that the fuel consumption

becomes large.

Based on the trial results and the socialization that

have been carried out, it can be said that the purpose

of this study has been achieved. However, the

development of tool design needs to be carried out

continuously in order to meet the needs of presto

milkfish entrepreneurs or producers, as well as tools

that can function more effectively and efficiently.

During the socialization there were several inputs

from the participants, for example about the size of

the presto pan. They suggested to create smaller pan

for first-step-entrepreneurs whose production was

still in a small quantity. This is a good input for the

implementing team. The follow-up-step is the

modification and dissemination of the tool. The size

of the presto pan can be varied, for example the size

for the capacity of 20, 30, 40, and 50 kg. Thus the user

has a lot of capacity choices, adjusting to the

production capacity and budget to buy the equipment.

Study of Pressure Cooker Application in Milkﬁsh Processing Industry to Increase Productivity and Quality

From the user side, there are also opportunities to

develop technical aspects of milkfish cooking

process. This is solely to get the best, effective and

efficient results. For example in regulating the

amount of temperature, pressure and cooking time.

From the previous trial, to reach a temperature of

100º C and a pressure of 1.5 atm, it only takes about

20 minutes. Then when the fire decreases, the

temperature only drops around 5º C and the pressure

is relatively constant. In the previous experiments,

after 2 hours of cooking time, the milkfish cooking

process was complete, the stove was immediately

turned off and the pressured air discharge valve was

immediately opened, and the milkfish was taken.

Seeing the above conditions, even though the

stove has been turned off, the temperature and

pressure are still relatively high. This actually can still

be utilized in the process of cooking milkfish. For

further study, it is necessary to carry out another trial

in one condition that the ignition duration is only 1.5

hours, but the opening of the air valve is longer, for

example 2 hours or more. If the trial yields good

results, surely this can be a new innovation. Thus, it

can be ascertained that the consumption of LPG fuel

is more efficient than the previous process.

Additionally, this milkfish cooking equipment

can actually be used to cook any food ingredients, not

just presto milkfish. Processed foods other than

milkfish such as presto chicken (soft bone chicken)

and presto nuts. Entrepreneurs can do other

innovations, such as making presto food from other

ingredients, such as ducks, crabs, eels, catfish and

various other foods.

The results of this activity were felt to be truly

beneficial by the presto milkfish businessman. This

can be seen from the comparison of new tools with

the old tools used so far. With old tools, 3 kg LPG for

4 x cooking process (@ 3 hours) x 5 kg = 20 kg

milkfish. While with milkfish cooking products

development results: 3 kg LPG for 3 x cooking

process (@ 2 hours) x 40 kg = 120 kg milkfish. So the

ratio of fuel consumption of old equipment with new

equipment for the same production capacity (120 kg)

is 6: 1. In terms of capacity production, the new

equipment can reach 8 times more in capacity.

Against presto milkfish cooking equipment

LTHPC, Arista (2010) has conducted research on the

effect of pressure and cooking time on the quality of

presto milkfish. The results concluded that the

optimum pressure and time in the pressure cooker

were to obtain the expected quality of milkfish at a

pressure of 1.5 atm and cooking time of 2 hours.

Based on the results of organoleptic tests on

variations in pressure of 1.5 atm and time of 2 hours

has the highest value, because the variation has good

quality which includes better appearance, taste,

aroma, texture and color compared to other variations

of pressure and time. For the levels of protein, fat and

water at a pressure variation of 1.5 atm and a time of

2 hours is about 11.6%, 31.1% and 39%.

Meanwhile other studies show similar results, that

the best value for all temperature parameters is by 120

minutes heating (Tapotubun, AM, et al, 2008: 69).

Compared to presto milkfish which is produced with

other tools, presto milkfish—which is cooked with

LTHPC, contains higher protein. It is found that

presto milkfish cooked with LTHPC has higher

protein of 11.6%, sample X (with other machine) was

only 5.19%. Even in sample Y (with other machine)

only 1.645%. (Test results at the Chemical

Laboratory of FMIPA Unnes, December 16, 2010).

4 CONCLUSIONS

Based on the previous discussion, it can be concluded

that.

In this study, a set of soft thorn milkfish (presto)

cookers with automatic temperature control has been

produced. The technical specifications of the tool are

as follows:

Height: 80 cm

Diameter: 55 Cm

Pot Material: Stainless Steel (SS 304)

Pan Thickness: 3 mm

Capacity: 40-50 kg of fresh milkfish

Number of Shelves: 10 Shelves

Fuel: LPG

Cooking time: ± 2 hours

LPG consumption: ± 1 kg / process

Presto milkfish cooking equipment has been

proven to be able to increase productivity and product

quality. Compared to traditional presto cooking

equipment, this tool has several advantages, which

gives benefits such as greater production capacity,

time saving, fuel saving, cost savings, and better

presto milkfish quality.

To produce milkfish with new tools, it is necessary

to adjust the cooking temperature of milkfish at about

110º C, a minimum pressure of 1.5 atm, and a cooking

time of about 120 minutes. However, the parameter

setting is not yet standard parameter, especially the

time variable because it is influenced also by the

volume of raw material being cooked.

In order to economize the consumption of LPG

fuel, the temperature control must be set twice. The

second setting is about 10º C below the first

temperature setting.

EIC 2018 - The 7th Engineering International Conference (EIC), Engineering International Conference on Education, Concept and

Application on Green Technology

5 SUGGESTIONS

There are several suggestions regarding the results of

this study as the following:

It is necessary to follow up further production in

terms of pan size variation with a capacity of 20, 30,

40, and 50 kg. This is to support milkfish producers

who have minimum production capacity and financial

capabilities.

The device user is expected to be able to conduct

further tests,in terms of etemperature variation,

pressure, and cooking time, in order to obtain the best,

effective and efficient results.

To the KSM management of "Soft Thorn

Milkfish", it is expected to make the best use of the

presto milkfish cooking equipment and be able to

disseminate this technology to the members.

The continuity of activities requires the support of

relevant parties in disseminating this appropriate

technology, including the Marine and Fisheries

Service, the Industry Agency, the Cooperative

Service and the UMKM, as well as other parties

concerned with the development of UMKM.

ACKNOWLEDGEMENT

Our thanks are for those whose direct as well as

indirect asssistance have supported this study,

especially to the Directorate of Research and Public

Service (DRPM) of the Ministry of Research,

Technology and Higher Education as the funder. Our

gratitute also goes to the Chairman of LP2M UNNES,

Dean of the Faculty of Engineering, Chair of the

Department and Chair of the Laboratory of

Mechanical Engineering and Chemical Engineering

UNNES. Last but not least, we give many thanks to

the chairman and members of KSM "Soft Thorn

Milkfish" in Semarang City, as their participation to

fully support the success of this study.

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Arista, Dian. 2011. Pengaruh Tekanan dan Waktu terhadap

Kualitas Bandeng Presto dengan Menggunakan

LTHPC. Skripsi. Jurusan Teknik Mesin FT Unnes.

Harsokoesoemo, Darmawan. 2014. Pengantar

Perancangan Teknik (Perancangan Produk). Bandung:

ITB.

Hurst, Ken.2006. Prinsip-Prinsip Perancangan Teknik..

Jakarta: Erlangga

Instruksi Presiden Republik Indonesia Nomor 3 tahun 2001

tentang Pedoman Pelaksanaan Penerapan dan

Pengembangan Teknologi Tepat Guna.

Saparinto, Cahyo,. 2006. Bandeng Duri Lunak.

Yogyakarta: Kanisius

Suhaeni, Neni, 2007. Petunjuk Praktis Membuat Bandeng

Presto. Bandung: Medium

Sonhadji, Ahmad. 2012. Manusia, Teknologi, dan

Pendidikan. Malang: UM Press

Syarif, Rusli. 1991. Produktivitas. Bandung: Angkasa.

Tapotubun, A. M, dkk. 2008. “Efek Waktu pemanasan

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Study of Pressure Cooker Application in Milkﬁsh Processing Industry to Increase Productivity and Quality