Monday, August 29, 2011


The most striking feature of British architecture is that most of their multi storey terrace houses remained the same throughout the years even though they are built in the era of the World Wars. The houses generally do not changed and have the same monotonous design that have withstand the test of time.
You could call it boring and monotonous, with the houses exhibiting the typically British Bay windows but it stood the test of time. Maybe this is what we called architectural conservation.
However, the modern architecture of terrace houses in Britain are different but still retaining the uniformity of small glass windows for better energy conservation. Often these modern houses are built with brown orange bricks
What ever the buildings are they are generally well kept and maintained
In Malaysia, the picture is different. Most of the double storey houses, that even include bungalows and semi detached houses are often renovated with building extensions, such as addition of porches and building extra rooms that do not take into account the conformity of the buildings with the surrounding buildings. It is almost the house owners are given a free hand in deciding how their houses look like. Of course they still have to adhere to certain building laws or by laws of the municipalities.
However, the end result is that the rows of houses looked ugly and appear as ‘squatter houses’
If the owners are restricted in their renovation, the architecture of their neighborhood would have been conserved and the beauty of the houses retained!
It is also a sad observation that once a building is bought, that is often their last major paintwork the building will have. So it is not surprising the sad state of appearance of the buildings which becomes more of an eyesore than a delight to the sore eyes.
The architects need to find a practical solution to all these problems by recommending laws or even in their designs of buildings with low maintenance.

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Sunday, August 28, 2011


Alcoholic beverages produced by fermentation are common among many countries throughout the world. The various types of alcoholic beverages produced by various countries are more a reflection of the differences in the type of carbon substrate used in the fermentation rather than the differences in the biochemistry of the alcoholic fermentation itself. Thus it’s not surprising that different names are given to different alcoholic fermentation from sake, tuak, arak, wine, toddy to even beers among others
Of course some of these alcoholic drinks are expensive while there are others which are cheap. This depends to a degree on the characteristics of the fermentation process and its products. Not withstanding that, all these alcoholic beverages are characterized often by the concentration of their alcohol or to be more precise its ethanol content.
It is a fact that refined alcoholic drinkers go for more than just the alcohol content but for the bouquet and other characteristics while the more hardened alcohol drinkers will go for alcoholic drinks which are very high in their alcohol content.
If we go to the hypermarkets or shops selling these alcoholic drinks we generally see a range of alcohol concentration. Beers are about 4% alcohol and wine can go higher.
Whiskies, rums and gins will have alcohol content that can send you into state of comatose or drunken stupor if you a first time alcoholic drinker
It is not uncommon to see people with problems or facing hardships will try to find solace in these drinks. The stronger the drink in terms of alcohol the better it is for them. But in reality the alcoholic drinks will never solve their real problems…..! It is not uncommon therefore to see these drunkards making a fool of themselves under the control of alcohol. But on the positive side there are many who claim chilli crabs tastes fantastic with alcohol!
Due to the search for higher alcohol content drinks many attempt to increase the alcohol content by trying to remove or reduce the water content of the alcoholic drink.
There are basically two methods to do this. In both methods you do need to appreciate some understanding of chemistry on the topics of miscibility and boiling points and freezing points
First method is by distillation. The distillation process has been used since ancient times to produce alcoholic drinks with a higher alcohol content. In distillation process the fermented solution is heated to certain temperature to form vapour. The vapour having higher content is cooled with higher enrichment of alcohol.
The second method is by controlled freezing of the fermentation products. As ice is solidifying, the concentration of alcohol in solution will remain higher
It should be warned here that these processes might be illegal in certain countries. So please check your laws

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There are two kinds of microbes in the fermentation industries; the good microbes which drive the fermentation industries and produce valuable fermentation products and the bad microbes which create problems in the fermentation industries. The problem is how are we going to prevent, remove or kill these bad microbes? Their removal would mean the desired fermentation process would be better in terms of fermentation products produced
There are commonly two objectives in removal of the unwanted bad microbes:
1 Kill the bad microbes
2 Remove the bad microbes by physical means
3 Prevent their growth or reproduction
In most fermentation industries steps 1 and 2 are the most common procedures. In this context of killing or removing the bad microbes it would either mean killing the living bad microbes (1) or killing and removing OR keeping their numbers low to an acceptable level (2)
All these above actions should be taken without affecting the good microbes! Remember that these actions do not differentiate between the good or bad microbes. So proper techniques in fermentation technology must be applied to ensure only the bad microbes are affected
In killing or removing the bad microbes we have to understand and differentiate the various terms which are commonly used interchangeably to describe the action. The most common terms are:
1 Sterilisation
2 Sanitisation
3 Disinfection
No matter there are differences in the 3 procedures, the common factor is that the bad microbes are killed or removed. But to the level of efficacy of microbial removal or killing depends on the procedures used and the various operating parameters
Theoretically in sterilization, it should be complete 100% removal of all living forms. It also means 100% killing of the microbes
In sanitization, it is often the removal or killing of microbes to the desired level. It is not a process of 100% removal.
In disinfection, it is more a sanitization but involving a surface or area. Most disinfection are carried out using chemical disinfectants and surfaces
So we can see the lines separating the three activities are actually vague.
Which method we use really depends on the purpose and objectives we have in mind.

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Tuesday, August 23, 2011


I remembered on one occasion, a research student carrying out nutritional studies for antibiotic fermentation using shake flask cultures. The experimental design looked simple enough whereby the organisms were grown with lipid as the source of carbon for the antibiotic fermentation.
The problem is the experiment was poorly carried out and serious erroneous conclusions were obtained from the experiment.
The research supervisor and the student failed to observe that:
1 Much of the loss in carbon in the media in the form of the lipid was not due to its utilization by the microorganisms, but ending sticking on the sides of the inner walls of the shake flask
2 Emulsifiers that were used to break the lipids into small globules for the ease of action to be metabolized by the microorganisms in fact contain citric acid. Citric acid as we know it is part of the TCA cycle and are preferably taken up and metabolized by the microorganisms compared to the longer chain hydrocarbon
Sad to say these observations were not taken into considerations and resulted in the wrong conclusions derived from the study!
It is therefore very important that before the start of any serious experiments studies and research must be done to ensure that the experiments are properly carried out. It is times like this where peer review and criticisms should be welcomed and the input into the experiment appreciated

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Saturday, August 20, 2011


These are two common terms which are often used erroneously or interchangeably to describe almost the same process.
Pickling refers to a process whereby food usually in the form of vegetables is preserved in a solution of brine or vinegar to give it the unique taste.
The first part of pickling involves the fermentation process. There are microbes involved in the fermentation process such as lactic acid bacteria which were natural flora of the vegetables.
The second part of pickling involved the storage of the fermented vegetables in vinegar. Adding the vinegar will bring down the ph of the pickles to very acidic values about ph 4.6 which help in the preservation but also killed all the bacteria
Fermentation is also the process of food preservation where sometimes salt are also added. There will be involvement of fermentative microorganisms. The main difference is that the organic acids produced in fermentation are the fermentation or metabolic products of the microorganisms. Strictly speaking vinegar is not added in the preservation

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Friday, August 19, 2011


If I am not mistaken there are at least three public universities in this country regularly advertising or carrying out fermentation technology workshops. The syllabus of the fermentation technology workshops carried out by these universities are about the same .
I often wonder the purpose and the target groups to which these workshops are intended. The subject of fermentation technology is more geared towards the high end users or industries ( of which we have almost none). These fermentation technology workshops are geared especially for those that can afford the huge capital costs equipments or for those doing teaching and research in the academia. Therefore will such workshops be economically viable?
In Malaysia, our type of fermentation industries is not that competitive with such advanced nations that do require the use of such sophisticated outlay of equipments. Maybe to be more relevant we only need ONE training centre for such workshops. In our case in my personal views we simply have too many pilot plants in fermentation technology that it is no longer economically viable for too many workshops.
What we need perhaps are more in adapting the existing fermentation technology applications and principles to suit our local industries of which we have our specific niches. It does not help our local cottage fermentation industries to learn, operate or even own such advanced fermentation technology equipment. It simply doesn’t make sense! What our industries need are simple construction of self made fermentors or sterilizers. Our industries need to learn more about the importance of optimizing,controlling contamination and improving aseptic techniques
What we need is how to transfer the principles of fermentation technology to the traditional industries where they can understand or improve their production without having to invest in costly fermentors. As it is our industries are already saturated with various kinds of labels such as MSC status, Bionexus, QC, HACCP etc etc but with nothing much really happening.
Let us have a paradigm shift and instead conduct fermentation technology workshops which are more relevant to the traditional fermentation industries. Teach the operators and improve their processes and not be isolated in the empty pilot scale fermentation plants!

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Wednesday, August 17, 2011


The common term scale up in fermentation technology has been used frequently without really understanding the true meaning of scaling up. This state of confusion has often resulted in studies which are not really scale up but just ordinary fermentation research.
The objective of scaling up studies is to reproduce the same conditions of fermentation efficiency even though there is a great increase in the volume of the fermentor. Scale up is the well planned exercise passing through various stages of increasing volume so as to achieve the industrial production scale with full confidence.
The scale up exercise strictly speaking does not include the stages at the level of inocula development, Petri dish and shake flasks studies. This stage is still considered the preparation or the basic research studies that will ultimately lead to scale up studies
In scale up studies the increase in the volume of fermentors are increased by magnitudes rather than arithmetical increase. But what I have seen in the scale up laboratories or fermentation plant, the type of fermentors used in scale up generally are not designed for scale up! And yet they are very proud in declaring they have a battery of fermentors that can be used as scale up!

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I know this article should have been introduced in the earlier part of this blog. But by doing so I believe I would have succumbed to the normal approach of introducing the subject of fermentation or fermentation technology. This would have made the standard approach boring and the readers of the blog would have thought that there’s nothing new or exciting to learn about fermentation technology.
Instead I have opted to introduce the history of fermentation technology by letting the readers of the blog discover the spread and depth of this topic and to appreciate the subject of fermentation technology less from the traditional history approach but much more from the critical point of view
It is true that the understanding of fermentation technology have its roots far deep in the past or early beginning of human civilization. It should be noted that from the spread of fermentation activities occurring almost in all countries and civilizations, its discovery must have been independent of specific country. It could be considered as more as parallel evolution in the knowledge of fermentation.
Sad to say that despite these observations, there are still some countries or nations which regarded that the fermentation process is their sole copyright in the evolution of human history. If only they realized that the discovery of alcoholic drinks and even fermented food such as fish undergoes the same process with the same microorganisms. The only significant difference is in their naming of the fermented products in the language of their country. Guess the pride of these people is the reflection of their own ignorance of the developments in fermentation in other countries besides their own. (The black age of ignorance of the past is still thriving in the modern minds of the uneducated today!)
The beginning or the discovery of fermentation or fermentation technology is very closely inter twined with ignorance and even religion. There is a general belief in the past that magical forces act to transform the food materials into fermented products. Despite the proof by Pasteur and the wide scientific studies on fermentation today, things have not changed much from the past. There are many human civilizations still believing the presence of forces or spirits to allow fermentation to occur. Even in this modern age the making of certain fermented foods such as tapai or fermented substrate is restricted by the various taboos. If these taboos are broken the fermented food or beverage would not turn well.
There is no such things as taboos to explain the failures but more the problems of contaminations and lack of understanding of the fermentation technology knowledge.
In the Roman mythology they even have honored the fermentation process especially with regard to wine by having a Roman God of wine named as Bacchus. So it is not strange if our own medicine men took to the wine to dance and get into the trance !!
Nothing have changed much from the earlier days of discovery of fermentation to what fermentation is today. The input of engineering and the inventing of the fermentors only help to improve the efficiency of the fermentation process. Strange it may be as in the case of many fermentation products such as antibiotics the many fold increase in the volume or concentration of fermentation products is attributed not so much by the improvement in the design of the fermentors but by the improvement in the fermentation productivity of the strains
In fact the design of fermentors have not changed much from the days of Fleming. Today they are still arguing on the problems of stirrers and impellers…. and rudimentary novel bioreactors.

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Sunday, August 14, 2011


Most fermentors on the market are generally provided with the Rushton type impeller irrespective of the type of fermentation process carried out and the nature of the fermentation broth rheology. It must be bear in mind that the Rushton impeller is not the universal or standard impeller available. There are many choices of impellers available and the experienced or educated fermentation technologist should have the confidence to choose the right impeller for the right fermentation process
Choosing the most suitable stirrer and impeller system is not easy and one could not rely entirely on the ‘advice’ given by the salesman. He has the job of selling and pushing his products to you and will promise you everything. After all a lot of business is based on deception or the ‘second hand car dealer’ bag of lies
The basics of using stirrers and impellers in a fermentor are to provide mixing and homogenous conditions that will enhance the various mass transfer processes. There are many factors to be considered when choosing the right impeller and stirrer such as speed, power consumption, volume of fermentation broth to even the shape, size and geometry of the fermentor
The objective of any mixing is not to overmixed or undermixed the fermentation broth. Instead the stirrer and impeller should be able to provide a ‘comfortable range’ of mixing where the objectives are met without extreme damages or negative effects to the fermentation process.
This knowledge can only be achieved through experience and sound advice acquired from other fermentor users. But what ever, totally relying on the universal Rushton impeller for all your fermentation mixings is not the right move.

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Saturday, August 13, 2011


As important it is to do scale up exercises in fermentation technology especially for new studies involving new fermentation process or modification of existing fermentation process, the exercise itself is not simple and cannot be executed in one or two simple steps involving one or two parameter studies.
Most fermentation technologists in their first exposure of the scale up exercise would just think just having a few fermentors of different sizes or just monitoring some basic ‘rules of the thumb’ such as tip speed studies they will be able to complete the studies to reach the necessary confidence.
It is far from that, as we know it ourselves that the fermentation process is a very complex process involving various phases that affect the behavior of the microorganisms. IT IS NOT JUST A SIMPLE MATHEMATICS OR ENGINEERING CALCULATION OR EXTRAPOLATION!. It is not easy to achieve the ideal state of trying to reproduce the efficiency of the fermentation process obtainable on small scale studies to at those at larger scale involving several magnitudes in the increment of volume
If we look at the various components in the fermentation process in the scaleup the behavior of the various parameters show different results or behavior. In such a way even before scale up studies are done, detailed studies and understanding of the process of the fermentation must be deeply understood.
The trouble is that most textbooks on fermentation technology seem to present the model of scaling up as being to easy and discussing the topics in such a brief account with a sprinkle of a few formulae
Scaling up understanding are often acquired through real experience and through trial and errors. There is no ‘short cut’ about it. You need to adjust as you go on and to have inputs not only from books but research papers in the journals!

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The raw materials used in fermentation constitute the substrates for the fermentation process. The substrates could be seen as either the raw materials that will be ultimately transformed into the desired fermentation products or they could be regarded as the source of nutrients for the fermentation microorganisms.
The substrates form the bulk of the fermentation broth and often considered as one of the most important component in the cost of the fermentation products. Thus in order to lower the costs of production the search for the most cheapest and economical source of fermentation substrate will be the top most agenda in any proposed fermentation industry.
The search for the most suitable substrate is not only dictated by costs and availability of the substrate but by other factors such as complexity of unwanted reactions that affect not only upstream, midstream but downstream activities. This would also mean the problem of treating its effluent from polluting the environment
In most cases the search for the right fermentation substrate or its admixture composition started with the detailed nutrient elemental analyses. Generally a single source of substrate do not have the sufficient composition to fulfill all the requirements as the fermentation substrate and a concocted admixture is often created to make it ‘wholesome’ or complete as the ideal substrate
Some of the recipes of the fermentation substrate is determined or created in the laboratory where the necessary type and concentration of media is determined as if it is a recipe. Experiments and complex chemical and elemental analyses would be carried out by using various analytical methods and its suitability by carrying out nutritional and physiological studies involving petri dish to even small fermentors
After all just having a fermentation media complete with all its composition does not always guaranteed the suitability or success for the fermentation
The source of the fermentation substrate should be cheap economical and easily available. This is a problem usually involving high volume low cost fermentation process. Pure chemicals though idealistic would send the fermentation costs shooting to the sky! And would not be economically viable unless the fermentation product is high cost and low volume
Such source of cheap fermentation substrate for high volume low cost fermentation has only one possible source that is the unwanted cheap agricultural or industrial waste products. After all to the microbes they don’t see it as dining at expensive restaurant; a food or nutrient is just a source of nutrients or elements
It is of utmost importance that the source of waste products for fermentation is not only cheap but continually available in stable supply. Several alternative sources for contingencies must always be taken care of as good logistics procedure

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In the previous blog, I have discussed the design of the fermentor and the concept that there is no such thing as a ‘standard fermentor’ although the various fermentors used almost similar system requirements.
When we say that we are ‘customising’ a particular fermentor it means that the fermentor is designed and built for a specific fermentation process. It is not designed for the use of other fermentation process.
The concept of a standard fermentor means that it is a general fermentor that can be used or modified for various types of fermentation process. The concept of the ‘ standard fermentor’ is to simplify it so that it is easily understood for those who are in their beginning to learn fermentation or to use fermentor in their novice stage.
But as you advanced in your research and understanding of the limitations and capabilities of fermentors you tend to prefer to ‘ customise’ your fermentor so as to provide specific solutions to your problems.
In certain cases of customizing such as in the use of novel bioreactors, the fermentors do not at all looked like the standard fermentor. The use of standard design fermentors would not be able to provide the answers to your problems.
In certain cases, extreme modifications are made in customizing the fermentor.
This is one of the example where issues arise during scaling up or scaling down studies. The exercise is looked as a simple exercise where the use of similar geometry seems to be the easiest way to find the answers. No wonder such studies do not really help or give the accurate answers…….

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Thursday, August 11, 2011


The presence of air or gases could be a complicating factor during autoclaving process. The volume that makes up the internal environment of the autoclave is filled with air. Air itself is a bad conductor of heat. So the presence of air in the autoclaving could affect the efficiency of the autoclaving process, unless these air are removed before the start of the autoclaving process.
The removal of air from within the autoclave could be carried out by heating the autoclave until active steaming is carried out. Once this is achieved the valve could be closed and the autoclaving process is started.
What is not often appreciated is that air is not only present in the autoclave but are also present in the spaces of the bottles, test tubes, fermentors and containers to be autoclaved. It is important therefore that this consideration be taken into account.
Sufficient time and heating must be given to drive these air out too or else the parameters for the sterilization cycle be modified if needed.

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One of the essential components in the use of autoclave is pressure. Autoclaves are usually operated at a higher pressure than the environment. High pressure is needed in order to achieve the sterilizing temperature of 121 degrees centigrade. Without pressure water can only boil at 100 degrees centigrade under normal atmospheric pressure. ( Of course at higher elevation such as on mountain tops, where the atmospheric pressure is less water boils at lower temperature!)
Generally pressure of about 15 psi is required for autoclaving. This pressure is achieved by heating the water in the sealed compartment of the autoclave. High pressure is due to the built up of the steam as the water is heated. There is a pressure safety valve in autoclaves that the high pressure is not overshot. ( This explains the regular hissing sound produced during autoclaving as excess pressure is regulated)
While it is very important to build the pressure to the correct value before autoclaving is initiated, it is also important that at the end of a sterilization that the pressure is brought back to normal values before the autoclave is opened to remove the sterilized items.
Heating and cooling processes take time. Most users are impatient for the time it takes to cool and lower the pressure. Impatience often results in users trying to speed up the release of pressure by opening the release valve too quickly. This action would result in the boiling over of the contents of the flasks and test tubes which could result in the wetting of the cotton plugs and increase the possibility of contamination.
Opening the doors to quickly could result in the sudden release of internal pressure by the autoclave. This could result in scalding of the body as the hot steam rushes out. Release of pressure must be done slowly and only when it reaches zero is the door of the autoclave opened

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The autoclave is one of the standard equipment in any fermentation activity or in the microbiology laboratory. Some of the autoclaves occur as independent units on its own while there are those which are in built into the fermentor for in situ sterilization. Irrespective most of these autoclaves are used for sterilization purposes. This is especially so in pure culture fermentation work where there is the need to remove the occurrence of unwanted microorganisms at the onset of fermentation. The autoclave is also used at the end of the fermentation run for sterilization or disinfection to avoid biohazards.
There are many options available in disinfection or sterilizations besides autoclaving. Yet in most cases in fermentation, autoclaving is the preferred method of sterilizations. Despite its wide usage there are many of us who take the autoclave for granted without understanding its principles of operations and even its limitations. In my years of autoclaving, everybody seems to remember the steps in the operation of the autoclaves without taking time to understand its limitations. The users have more faith in the operation of the autoclaves as 100% ‘fool proof’ and that there would be no problems with its operation or the efficiency of the sterilization process carried out using the autoclaves.
Thus it is often not surprising that often the quality of sterilization is poor and that the autoclave is not working to their expectations. By then it is often too late….. .
One of the biggest issues in having autoclaves is that often the autoclave in the laboratory have to accommodate all kinds of users (from students, post graduates, post docs and even laboratory assistants and attendants) Too many users with too many types of materials to be autoclaved who may vary from having to little knowledge to excessive pseudo knowledge in the proper use of autoclaves.
At some point, these users are exposing themselves to various health hazards from explosions to even being scald alive! REMEMBER! THE AUTOCLAVE IS IN REALITY A BOILER WHICH WRONGLY USED COULD RESULT IN HIGH PRESSURE AND HOT STEAM!
So many years observing autoclaving have seen many common mistakes made mostly attributed to poor understanding of the autoclave operation to the dangerous ‘don’t care attitude’
Common mistakes often observed have seen plastic trays used to hold the stuff to be sterilized becoming lumps of melting plastic, Melting agar flushed down the pipes resulting in blockages, over spilling of media and even projectiles of bolts and nuts!
Yet again and again lessons are not learnt as proven by the mistakes which occur repeatedly.
It is very very important that those using fermentors and autoclaves are properly trained in using the autoclaves to ensure their very own safety! Those that use the autoclaves need proper training and be supervised and to pass examinations on the use of autoclaves!

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