Mengenali Tongkat Ali Bersama Awang Ahmad (UMS)

HotScience | Petrosains
 
Awang  Ahmad Bin Mohd Yunus adalah seorang saintis dan juga merupakan seorang pensyarah kanan di Sekolah Perhutanan Tropika Antarabangsa, Universiti Malaysia Sabah (UMS), telah membuat kajian mengenai Tongkat Ali bermula dari tahun 2003 hingga kini.  Di antara inovasi beliau adalah:

1.    Teknologi tanaman Tongkat Ali di dalam ladang hutan.
2.    Teknologi tanaman Eurypot: Kaedah penanaman Tongkat Ali dalam keadaan terkawal.
3.    A-yamli: Makanan untuk ternakan ayam.

Awang Ahmad, Pensyarah Kanan dari Universiti Malaysia Sabah

Apakah itu Tongkat Ali?

Tongkat Ali merupakan spesies tumbuhan herba yang tergolong dalam keluarga Simaroubaceae. E. longifolia adalah salah satu dari empat spesies yang selalu digunakan.

Di Malaysia Tongkat Ali juga dikenali sebagai Penawar Pahit, Penawar Bisa, Bedara Merah, Bedara Putih, Ginseng Malaysia, Setunjang Bumi, Lempedu Pahit, Payung Ali, Tongkat Baginda, Muntah Bumi dan Petala Bumi. 

Secara amnya tumbuhan Tongkat Ali berasal dari Asia tenggara dan mempunyai taburan  majoriti semulajadi di Malaysia, Indonesia, Myammar dan Thailand. Namun sekarang, taburannya telah berkembang ke negara-negara Asia tenggara yang lain seperti Laos dan Filipina.  Ini mungkin disebabkan oleh faktor komersial dan potensi baru yang wujud serta faktor perkembangan teknologi dalam bidang pertanian dirantau Asia tenggara.


Kegunaan Tongkat Ali

Secara amnya tumbuhan Tongkat Ali mengandungi beberapa jenis komposisi kimia seperti Eurycomanol, Eurycomanone, dan Eurycomalactone yang mengandungi nilai perubatan yang begitu tinggi dan berharga. 

Dahulunya ia hanya digunapakai oleh orang-orang kampung atau luar bandar untuk tujuan perubatan tradisional sahaja dan bukan bertujuan untuk komersial - akar Tongkat Ali direbus dan dijadikan sebagai ubat sakit kepala, sengal-sengal tulang belakang dan sakit perut. Di Kemboja, Tongkat Ali berfungsi untuk meneutralkan bisa racun dalam badan, merawat demam kuning, dan kembung air manakala di Indonesia, ia digunakan untuk mengurangkan demam, melegakan mana-mana bahagian badan yang bengkak dan air rebusan Tongkat Ali ini juga sesuai dijadikan amalan sebagai minuman tonik kesihatan selepas bersalin mengikut kadar yang dibenarkan. Masyarakat di Vietnam pula menggunakan buah dan bunga daripada Tongkat Ali untuk merawat sembelit.

Kelebihan Tongkat Ali:

a.    Sebagai anti-oksidan (tujuh kali ganda lebih tinggi daripada Kacip Fatimah)
b.    Sebagai diet tambahan harian
c.    Berupaya mengurangkan kolesterol
d.    Berupaya menaikkan paras testosteron
e.    Berupaya mengurangkan paras gula dalam darah
(pastikan anda merujuk dengan doktor perubatan sebelum mengambil suplimentasi)
f.    Boleh ditanam sebagai pokok landskap


Sesi soal-jawab dengan En. Awang  Ahmad Bin Mohd Yunus

1.    Bolehkah air rebus daripada akar Tongkat Ali diminum terus?
Air rebusan boleh diiminum terus tetapi dos yang diberikan haruslah dipastikan sesuai. Contoh:
100 gram akar akan menghasilkan 3 gram ekstrak kering Tongkat Ali, dan penggunaan yang disyorkan adalah 50 mg sahaja.  Ini bermakna Cuma 1.5 gram akar kering diperlukan.

2.    Mana yang memberikan kesan sampingan yang minimum, air rebusan atau hasil ekstrak?
Hasil ekstrak lebih berkesan.  Ini kerana air rebusan amat pahit dan disamping itu kapsul lebih cepat tindakbalas dan kandungan adalah seragam.

3.    Apakah rekomendasi jenama/syarikat yang mengeluarkan Tongkat Ali untuk pengguna di Malaysia?
Jenama yang saya syorkan adalah Biotropics,  Ini kerana ianya dihasilkan dengan kaedah yang saintifik dan sumber yang digunakan adalah jelas.

4.    Bagaimana Tongkat Ali berbeza/sama daripada Viagra?
Tongkat Ali bertindak sebagai makanan tambahan dan lebih kepada meningkatkan tahap testoterone dan melancarkan pengaliran darah.  Ia juga adalah dari sumber tumbuhan. Viagra pula adalah dadah yang sintetik atau direkacipta.


Inovasi En. Awang  Ahmad Bin Mohd Yunus

1.    Teknologi tanaman EuryPot
EuryPot berasal daripada Eury= Eurycoma (Tongkat Ali) dan Pot (pasu) dan diperbuat daripada paip PVC dan bahan lain. Ia terdiri daripada tiga bahagian:
a.    bahagian utama (luar)
b.    bahagian kedua (bertindak sebagai system pengumpulan akar)
c.    bahagian bawah (penutup) - ditebuk dengan lubang-lubang kecil supaya air boleh mengalir keluar yang seterusnya akan menggalakkan penumbuhan akar yang lurus.

EuryPot juga mempunyai bahagian untuk tujuan pemotongan akar dan bahagian untuk rawatan pokok. Hasil inovasi ini boleh didapati dalam pelbagai saiz mengikut kesesuaian. Hasil kajian menggunakan EuryPot juga telah menunjukkan bahawa pokok Tongkat Ali yang ditanam semula setelah dipotong akarnya akan tumbuh dengan lebih baik dan sihat dari segi ketinggian, diameter, akar dan daunnya.

Kelebihan penggunaan EuryPot:
a.    Tidak memerlukan kawasan yang luas untuk penanaman.
b.    Sesuai untuk penanaman terkawal.
c.    Membolehkan penuaian akar Tongkat Ali dilakukan tanpa perlu memusnahkan dan mencacatkan pokoknya.
d.    Berjaya menghasilkan akar Tongkat Ali yang lebih lurus dan panjang.
e.    Lebih ekonomikal untuk kegunaan jangka masa yang panjang.

2.    Tongkat Ali dan Ayam = A-yamli
Menurut kajian beliau, ayam ternakan yang diberi makan dengan daun pokok Tongkat Ali yang telah diproses menghasilkan kandungan protein yang lebih tinggi dan lemak yang jauh lebih rendah. Selain itu, ayam-ayam hasil kajian tersebut adalah lebih sihat, mempunyai rasa yang lebih lazat dan tidak perlu diberikan suntikan hormon.


Tahukah anda?

a.    Dos ekstrak Tongkat Ali yang sesuai untuk pengguna lelaki Asia ialah 75 mg per kapsul. Elakkan daripada mengambil sebarangan produk Tongkat Ali kerana dikhuatiri mengandungi elemen merbahaya seperti plumbum!

b.    Lebah adalah “kawan baik” kepada tumbuhan Tongkat Ali.  Ini kerana ia memakan ulat harimau yang boleh menyebabkan kematian mengejut pada pokok Tongkat Ali.

Soalan untuk pembaca:

1.    Berapakah purata dos ekstrak Tongkat Ali yang sesuai untuk pengguna lelaki di Asia?
2.    Apakah nama saintifik Tongkat Ali?
3.    Adakah Tongkat Ali sejenis ginseng?
4.    Adakah Tongkat Ali dituai berdasarkan pokok atau akar?

Keep Our Beaches Clean

Since I was little, I have always wanted to walk on white sandy beaches with waters a deep blue, where you can see the fishes from above. Given that I could only see them on television, I have always thought that these paradise-like places are far away – in other countries. So when I saw a picture of Semporna Island – it was stunning! And when I realized that it’s in Sabah, I was very surprised! Never in my mind did I imagine such an idyllic paradise was here in Malaysia.

Stunning Cenang Beach in Langkawi. By Rohan Waghmare (Own work) [Public domain], via Wikimedia Commons

Although blessed with such natural beauty, regrettably most public beaches that I have visited in Malaysia are becoming an eyesore. Plastic bottles, food wrappers, polystyrene cups and even cigarettes are everywhere, some buried in the sands, others floating on the water. People are sometimes advised not to walk barefoot while on the beach as well as in the waters as the debris is not just an eyesore, but can be dangerous as well. Swimmers, beachgoers and tourists might get injured from stepping on broken glass bottles. Sea creatures such as turtles might mistake plastic bags for food or become trapped in the ropes or nets (which can be fatal). Even for the fishermen, the debris could do damage to their boats and impact their livelihood.

Trash at Pulau Perhentian. By Colocho (Own work) [CC-BY-SA-2.5 (http://creativecommons.org/licenses/by-sa/2.5)], via Wikimedia Commons

These past few years we have heard some efforts made by local authorities, corporations, as well as NGOs to keep the beach cleaner and safer. One of the efforts made are beach cleanups where volunteers gather and together they collect the debris along the shores, under the waters and sorted them out for recycling. This effort however does not promise a long-term solution. It is more important that we change our littering habits. When you go to the beach, you can do whatever you want – play, rest, run, jump – but the one thing you should not do is litter!

Petrosains PlaySmart recently organised a beach cleanup at Kuantan.

 The ocean is more than just a vast pool of water for sea creatures and humans to swim around. The ocean supplies oxygen, food and water to us. Therefore it is important for us to ensure our ocean is always clean and healthy so that we, too, are always healthy. Let’s be the change today and help clean up the shores for a start for a safe beach, pristine waters, and the continued preservation of the natural beauty of our oceans.

Join Petrosains in “Our Earth, Our Home” Weekend Special on 23^rd -  24^th March 2013. Join us for fun activities throughout the science centre. Our artistic face-painters  and energetic science buskers will be around to ensure that you have great fun too!

On 23^rd March 2013 there will be a special performance entitled, “Inspirasi Haiwan” at 11.30am and 2.30pm. This performance is about dance movement inspired by animals which will incorporate beautiful music and choreography as interpreted by ASWARA (National Academy of Arts, Culture and Heritage).

Shared by Iman, Communications Intern at Petrosains

The Under Appreciated Mangroves

Kuala Gula (Perak), Umbai Baru (Malacca), Pasir Penambang (Selangor) – These are some of the popular places where Malaysians travel to for a taste of fresh and scrumptious seafood delicacies. My parents are among those food enthusiasts who are willing to travel far and wide for food.  Me? As long as crabs and shrimps are around, I am all set!

By megawatts86 (originally posted to Flickr as More Chilli Crab) [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons

No matter where you go - Perak, Johor or even Sabah –the restaurants are mostly located by the shores, some even ‘float’! As you enjoy your hand-picked crabs, shrimps, clams and fishes, you can see fishermen maneuvering their boats- some are heading back to shore, while others are heading out to the vast sea. The one thing that these places have in common (other than the freshly caught fishes) is the mangrove.

Even for nature aficionados, the mangrove is the quite under-appreciated. Most of us, myself including, are biased to things that are beautiful and postcard-perfect – such as scenes of sunset at the beach, soaring mountain peaks, lush rainforests, and fields of flowers. Although I have been to the less photogenic mangrove forests a few times, the mangrove never caught my eyes – being just rather plain blanket of trees and roots anchored on wetlands.

By kakna's world (http://www.flickr.com/photos/kakna/6985181102/) [CC-BY-SA-2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons

At HotScience, Petrosains’ bustling area in its lobby that communicates current and relevant science, I was quite surprised to see the variety of products developed by researchers from Universiti Malaysia Terengganu (UMT) that are made from mangrove trees. Apparently, the most ‘utilized’ mangrove tree is Nypa fruticans or simply known as Nipah. The leaflets are woven onto hats, mats and rooftops, while the sap collected from the flower stalk is made into drinks, ice-cream, soft candy and pudding. In addition to that, mangrove barks make the best quality charcoal and most cosmetic companies from Japan and South Korea import mangrove-based charcoal to be developed into cosmetic products such as facial wash. 

Mangroves, due to its muddy and swampy nature, at times can be quite stinky and unpleasant looking, and home to some fearful crocodiles and snakes, which do not help gather much support for mangrove preservation.

Food and Agriculture Organization (FAO) of United Nations claims that mangrove extinction is at an incredibly high rate, with Malaysia having lost approximately 16% of its total mangrove forest between 1980 until 2005. Mangroves are important breeding grounds for many animals such as crabs, shrimps, and fishes, but in Malaysia, mangroves are mostly being cleared away to make way for man-made shrimp farms.
If this major loss of mangrove continues, soon enough, we might not be able to enjoy our seafood as much as we have today – and as a crab fan, I would be happier to have the crustaceans abundant in Malaysian shores.

Fiddler crab burrows under mangrove roots.

 Yes, it is difficult (for some) to care or nurture some kind of feelings towards mangrove (or plants in general). They do not show facial expressions as other mammals or even respond to you when you talk to them, but they are called living creatures for a reason. So, let us be more appreciative towards mangroves and nurture ourselves into loving them!

Join Petrosains in “Our Earth, Our Home” Weekend Special on 23^rd -  24^th March 2013. Join us for fun activities throughout the science centre. Our artistic face-painters  and energetic science buskers will be around to ensure that you have great fun too!

On 23^rd March 2013 there will be a special performance entitled, “Inspirasi Haiwan” at 11.30am and 2.30pm. This performance is about dance movement inspired by animals which will incorporate beautiful music and choreography as interpreted by ASWARA (National Academy of Arts, Culture and Heritage).

Shared by Iman, Communications Intern at Petrosains

Counting Down to Earth Hour 2013 - Show Your Support!

The Sydney Opera House, the Eiffel Tower in Paris, Taipei 101, the  Beijing National Stadium, and of course the Petronas Twin Towers in Kuala Lumpur – all these landmarks are often seen lighting up the city skyline but tomorrow, these landmarks and many more will go dark! On this Saturday, March 23rd many iconic buildings both large and small the world over will turn off their lights for an hour in a show of support to the annual Earth Hour event.

Earth Hour is a global movement to raise awareness on climate change. Due to mankind, our planet is going through a critical phase in which global temperatures are rising on average and showing no signs of stopping. However, many are still unalarmed and pay no heed to the dire scientific findings, predicting a disastrous state of events for our environment in the future if nothing is done today.

Earth Hour kicked off in Sydney in 2007, the brainchild of Andy Ridley who is the CEO and Co-Founder of Earth Hour. On 31 March 2007, over 2 million people and 2,000 businesses in Sydney went dark for an hour, and subsequently inspired the world to do the same. Just last year, the wave of support for Earth Hour is almost global, encompassing hundreds of millions of people in over 152 countries, including Malaysia.

Most people would think such simple gestures will not make a difference. That is simply not true. Everyone needs to remember that it is the cumulative effect which makes a huge impact to the environment. Everyone has to play a part for the small efforts to be impactful.

In 2011, Earth Hour changed its logo from ‘60’ into ‘60+’, to indicate that the effort to protect and preserve our planet must move beyond the hour. Through its ‘I Will if You Will’ campaign, the annual event dares people to do more than just switching off lights.

Malaysia is taking up the challenge this year. Recently, the Mayor of Kuala Lumpur, Datuk Seri Ahmad Phesal b. Hj. Talib promised to cycle to work on March 25th if at least 50 buildings in Kuala Lumpur switched off their lights for Earth Hour. The Mayor will also join in the Petronas Twin Towers Lights Out this Saturday from 8.30pm until 9.30pm.

By Lai Seng Sin [GFDL (www.gnu.org/copyleft/fdl.html)], via Wikimedia Commons

So for the rest of us, let us support this global effort not necessarily by switching off the lights for an hour but to always consider the environment in our day-to-day practices. Let’s take up the challenge to make Malaysia and the world a greener, healthier and more sustainable place to live in. It’s the small things that matter most. Small efforts by ordinary people make all the difference. So please never underestimate the power that you have in saving ‘Our Earth, Our Home’.

Join Petrosains in “Our Earth, Our Home” Weekend Special on 23^rd -  24^th March 2013. Join us for fun activities throughout the science centre. Our artistic face-painters  and energetic science buskers will be around to ensure that you have great fun too!

On 23^rd March 2013 there will be a special performance entitled, “Inspirasi Haiwan” at 11.30am and 2.30pm. This performance is about dance movement inspired by animals which will incorporate beautiful music and choreography as interpreted by ASWARA (National Academy of Arts, Culture and Heritage).

Shared by Iman, Communications Intern at Petrosains

Si Belangkas Lapar! 8/8

Misteri Darah Biru! 7/8

Be A Hero For Your Planet – Tweet & Win COMBO tickets to Petrosains & Sultans of Science!

Be A Hero For Your Planet – Tweet & Win!

Hello all,

In supporting 'Our Earth Our Home' thematic celebration at Petrosains and Earth Hour, lets have some fun tweeting on what you had done so far to save our planet!

Tweet about it and tag us, you can use @petrosains or #petrosains in your tweet. Tweets can include photos as well. Be creative (but authentic)! Send your tweets between 20-23 March 2013 before 8pm daily. Best daily tweet will win COMBO tickets to Petrosains, The Discovery Centre and the Sultans of Science exhibition. 

The winners will be announced on 25 March 2013.

Also, check out what Petrosains' staff are doing to be green in our daily earth-saving tips on Twitter!

Terms & Conditions

1. The contest is open to all Malaysian residents.
2. The participants need to follow Petrosains' twitter account; @petrosains
3. Participants should tweet real and authentic efforts done in saving the planet.
4. Participants must use/insert #petrosains or @petrosains in their tweets; all tweets without these two handles will not be recognized for the contest.
5. ‘Be A Hero for Your Planet – Tweet & Win!’ will run from 20 until 23 March 2013, tweets for the day must be posted before 8pm daily.  
6. No limits to the number of tweets you want to post.
7. Best tweet of the day will receive COMBO tickets to Petrosains, The Discovery Centre and Sultans of Science exhibition.
8. Winners will be announced on Monday, 25 March 2013.
9. All results are final. Prizes won are NOT exchangeable for cash.
10. Petrosains Sdn Bhd reserves the right to change the Terms and Conditions of this contest without prior notice. 

Good luck and happy tweeting! 

Belangkas Melihat Dunia! 6/8

Kitar Hidup Si Belangkas! 5/8

Mencari Telur Si Belangkas! 4/8

Jenis-jenis Belangkas! 3/8

Kampung Si Belangkas! 2/8

Cerita Si Belangkas! 1/8

Argh! Everyday Monsters! - Getting Up Close with the Horseshoe Crab

At first sight, the 'Horseshoe Crab' or 'Belangkas' in Bahasa Melayu looked like a foreign, out-of-this-world creature. If I happened to see the crab crawling near me, I would definitely run away - just as I would get freaked out seeing a cockroach in the corner of the room! Apparently, I am not a fan of creatures with more than 2 pairs of legs... and this particular creature has five!

So when I first heard that Petrosains has on display some horseshoe crabs at HotScience (the public science engagement space at their lobby at 4th floor Suria KLCC), I saw it as a chance to see the amazing but hideous creature up close and well, 'safely'.

As I walked into HotScience, I was 'greeted' by two enormous horseshoe crabs, the size of a large frying pan. Surprisingly I was mesmerized by the look of it. Unconsciously I walked straight to the two crabs, being brave by the fact that they are contained in a glass box.

   

The horseshoe crabs in the glass container - definitely a sight!

I had such an interesting day with the scientists from Universiti Malaysia Terengganu (who were responsible for bringing the crabs to Petrosains!). Personally I think this is a wonderful effort by Petrosains in getting our local scientists to engage with the public. There are so many things that they shared with the visitors during the session. Knowing that they had been handling, sampling, researching and learning about horseshoe crabs for years was a revelation; the work of a scientist is definitely not contained only in labs.

I know there are many other scientists out there with so many interesting and mind-blowing work, I think they should take this kind of initiative in making their hard-work visible into something more engaging and meaningful to the public. From the way I see it, it was also a learning experience for the scientists. They had to attend to numerous unexpected questions and some had to even learn to communicate with visitors from all around the world.   



By my experience of observing and cowardly touching the 'alive' horseshoe crabs that day, I have come to learn that they are not as hideous, scary and dangerous as they appear to be.

I was told that there are four types of horseshoe crabs and amazingly, three out of the four can be found right here along the coasts of Malaysia.  The horseshoe crabs are also said very romantic for they are always found in pairs. Once they have met, they took the vow 'until death do us part' dead serious.

If I were to compare them to other sea creatures, I would say they are as gentle and as harmless as a starfish. And unlike the fast-swimming sailfish, horseshoe crabs are slow movers.  So if you happen to encounter this sea creature while strolling along the beach with your family and friends, don't be alarmed by their appearance. Instead, take the time to admire its graceful beauty and appreciate the diversity of nature that we have in Malaysia.  



Visitors get a chance to handle (with care) the horseshoe crabs.

    

Shared by Iman, Communications Intern at Petrosains

Malaysian Delicacy: Cencaluk

Memang tidak sah  sekiranya hidangan makanan di negeri Melaka jika tidak disertai dengan cencaluk.  Melaka adalah sebuah negeri yang terletak di sebelah pantai barat Semenanjung Malaysia dan juga di gelar sebagai Melaka Bandaraya Bersejarah. Sesiapa sahaja yang berkunjung ke negeri ini, pastinya tidak akan melepaskan peluang untuk menikmati cencaluk dan berkunjung ke tempat-tempat yang bersejarah.

Cencaluk ialah sejenis lauk yang popular dalam hidangan tradisional Melaka yang dimakan bersama nasi. Cencaluk diperbuat daripada udang halus yang lebih dikenali sebagai udang geragau. Merujuk kepada gambar di bawah, kita dapat melihat udang-udang geragau yang berada di dalam botol setelah dijadikan cencaluk. Oleh kerana ia diperbuat daripada udang geragau, cencaluk mengandungi kandungan protein yang tinggi.

Cencaluk

Di negeri Melaka, udang ini boleh didapati pada musim tertentu di beberapa kawasan persisiran pantai Melaka.

Cencaluk pada masa dahulu merupakan satu hasilan tradisional tetapi kini telah dikomersialkan dan boleh diperolehi dengan mudah menerusi penjualan yang terbuka seperti di tepi jalan raya, di kedai runcit malahan boleh juga didapati di kebanyakan pasar raya ternama pada harga yang berpatutan.

Cencaluk yang dijual di pasar raya

Adalah lebih menarik sebenarnya untuk kita mengetahui tentang proses pembuatan cencaluk. Ia seharusnya dilakukan dengan teliti supaya kualiti cencaluk itu sedap apabila dimakan.

Cencaluk telah dihasilkan melalui proses penapaian. Penapaian adalah satu proses penguraian glukosa dalam keadaan tanpa oksigen untuk menghasilkan etanol, karbon dioksida dan tenaga. Mula-mula, udang geragau yang segar dibersihkan dari kekotoran. Seterusnya ia dicampurkan dengan garam kasar dan sedikit nasi. Setelah ketiga-tiga bahan menjadi sebati, ia perlu dimasukkan ke dalam sebuah bekas seperti tempayan atau pasu kecil. Kemudian ia ditutup dengan kain bersih untuk diperam selama 3-4 hari. Ada juga pembuat cencaluk yang menambahkan sedikit air didih nasi bagi menambah kesedapan cencaluk.


Dalam pembuatan cencaluk, mikroorganisma di dalam nasi menguraikan glukosa dalam keadaan tanpa oksigen kepada etanol, karbon dioksida dan tenaga.

Selepas berlakunya penapaian, ia akan diikuti dengan proses pengawetan makanan.  Garam akan di campur dan bertindak sebagai pengawet makanan. Garam amat penting dalam proses pengawetan cencaluk kerana garam atau sodium klorida bertindak untuk merencat pertumbuhan mikroorganisma melalui proses osmosis. Larutan garam yang pekat mampu membunuh mikroorganisma supaya makanan akan lebih tahan lama.

Larutan garam adalah larutan hipertonik. Larutan hipertonik adalah larutan yang berkepekatan tinggi. Di dalam kes ini, molekul air adalah larutan yang mempunyai kepekatan yang lebih rendah sekiranya dibandingkan dengan air garam atau juga di panggil larutan hipotonik. Jadi, air dari dalam udang akan meresap keluar dari sel udang secara osmosis. Osmosis adalah proses pergerakan larutan dari kawasan yang berkepekatan rendah ke kawasan yang berkepekatan tinggi melalui membran separa telap. Jadi, air dalam sel udang akan hilang dengan cepat. Udang akan menjadi lebih tahan lama kerana bakteria tidak dapat hidup dan membiak tanpa kehadiran air.


Gambarajah adalah untuk menerangkan tentang proses osmosis. Molekul air (hipotonik) meresap keluar secara osmosis ke dalam bekas yang mengandungi air garam (hipertonik) melalui membran separan telap.

Osmosis

Kesimpulannya, sekiranya kita mengkaji tentang sesuatu pastinya ia mempunyai kaitan dengan ilmu sains. Apa yang kita boleh katakan di sini,  proses penapaian dan pengawetan adalah dua proses yang terlibat dalam pembuatan cencaluk.

Posted by Ayu
Learning Specialist, Petrosains

Malaysian Delicacy: Tapai Pulut

During my last holiday to the East Coast of Malaysia, I had some wonderful Malaysian food at Pasar Payang, Kuala Terengganu. One of the yummy Malaysian delicacies I had was 'tapai pulut' or fermented glutinous rice. It is very popular among Malaysians and normally eaten as dessert. Tapai pulut is an everyday dessert served at functions such as festivals and weddings usually by the Malay community in Malaysia. The taste is sweet with a pleasant aroma and it is wrapped in rubber tree leaves. Sometimes, it is also wrapped in banana leaves. 



Tapai Pulut in banana leaves



Tapai Pulut is made by fermenting glutinous rice (Oryza sativa glutinosa). What exactly is fermentation though? Fermentation is an anaerobic process in which energy can be released from glucose even though oxygen is not available.

My curiosity encouraged me to do further research on how Tapai Pulut is made. After reading a few articles and asking my mother, here are the steps:-

1.      First, wash the glutinous rice and soak it overnight

2.      Next, cook the glutinous rice

3.      When the rice is cooked, cool it

4.      Pound the yeast. Sprinkle it on top of the cooked rice

5.      Turn the rice over and sprinkle yeast on it

6.      Put the rice in an air tight container and let it ferment for 2 days

7.      After 2 days, the rice is ready to be wrapped in rubber tree leaves

8.      Keep it in the refrigerator until cool.

9.      It’s now ready to be eaten and enjoyed!



Tapai Pulut



Why do you think yeast is necessary? Yeast carries out both aerobic respiration and anaerobic respiration. Aerobic respiration takes place in the presence of oxygen while anaerobic respiration refers to the type of respiration that takes place in the absence of oxygen. Anaerobic respiration in yeast cells is called fermentation. During fermentation, yeast secretes the enzyme zymase which hydrolyses glucose in the absence of oxygen to form ethanol, carbon dioxide and energy.

                           Glucose            → ethanol + carbon dioxide + energy

                        C6H12O6           → 2C2H5OH + 2CO2 + energy

The enzyme zymase by the yeast speeds up the fermentation process. In the fermentation process, only a small amount of energy is released. A large amount of energy is still stored in ethanol as chemical energy. This is because glucose is not completely broken down in anaerobic respiration. The products of fermentation such as carbon dioxide, is used as a raising agent in baking bread while ethanol is used to produce alcoholic drinks such as wine.

Posted by Ayu
Learning Specialist, Petrosains