15 February 2011

Discussion on viscosity of sauce

Assalamualaikum and good evening.  I'm going to share experiments conducted by us. Well, it's better for me to explain background of the experiments. Complainants of customers as well as increasing cases of returned products due to quality deterioration were things that moot the idea for experiments to solve the problem that always occur in sauce production industry.

Deterioration of quality in this experiment refers to low viscosity condition of glass bottle 340ml chili sauce. It easily flows and note that sauce exhibits non-newtonian pseudoplastic behaviour. based on a book titled Understanding Food Science and Technology, written by Peter S. Murano, page 377" Shear thinning fluids are said to exhibit pseudoplastic behaviour. What this means is that the viscosity of the fluid decreases as shear rate increases." So, the problem with the sauce was that even though shear force was not applied,
still the sauce flows easily. This reflects the undesirable quality of sauce. It has very low viscoity.

Based on some company's standard, viscosity at 43dPa.s is the minimum accepted level. Sauce with viscosity lower than that of standard would be rejected from the market products. There are a lot of factors attributed to the deterioration of quality in terms of viscosity, namely storage condition, temperature, cooking
temperature and type of plastic.This writing would discuss the first factor, storage condition. While the
rest factors would be dealt with on the upcoming posts.


After we fill in the sauce into the glass bottle, it is capped, labelled. The bottles arranged on a carton that can place 24 bottles, wrapped and lastly transported into the store. There had been concerns that the way they
are stored in cartons that made heat to stay in the bottles for loner period thus, lowering its viscosity. Starch is the main component for the physical appearance of sauce including its viscosity. Based on our prior knowledge, gel formation concept, starch needs to reach gelation process upon cooling in order to become more solid and firm as well as of high viscosity. So, the sauce bottle that is kept in the store might store more heat, hence it does not reach cooling point causing it to be of higher viscosity.


So, in our experiment, we use two different kind of storage; room and store. Rightly after being packed filled, capped and labelled, the 340ml chili sauce was kept at room temperature and the other one variable used store condition. At the next day, samples are taken. and we found out that sauce kept at room temperature exhibited higher viscosity. To be continued...

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Reply:
can we add some starch based ingredients to make it more thicken...

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Reply:
either add starch  or give time for the sauce to cool.adding more starch into the ingredient would add more cost.giving time for cooling is also cost as time is money. (unless the production is not concerned about yield as the market demand is still asurplus for them)

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Reply:
from my experience....the sauce need to be cooled perfectly i think at least 35 degree..because what i found out before bottles sauce make into the cooling tunnel..the headspace is too little..but when they underwent the cooling tunnel...their headspace increase..means viscosity (much higher)..may be the cool water being
used need much lower temp..or the time for the bottles to undergo cooling tunnel need to be longer or lower the speed of conveyor inside the cooling tunnel in order to achieve desired temperature

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Reply:
but it sounds like there's no cooling tunnel .meaning they cool their product relying on the ambient?

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Reply:
Well, you're right. There is no cooling tunnel. We totally rely on the ambient condition for  the sauce to be cooled which is not quite effective for it to have higher viscosity. That is one of the main problems. For your information, there are two different modes of 'cooling'.

The first one is by straightly keeping the sauce into the store room after being packed nicely on to pallet. This refers to sauce with glass bottles.

The second mode is that the sauce at the production site for one night before being kept in the store room and this is applied for plastic bottles. And the viscosity problem normally emerged from the sauce of glass bottle.

The problem now is how to provide the cooling process in the store room which is not too cool, with opened air and no controlled ventilation system.

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Reply:
well then, you all just should apply the method of cooling for sauce in plastic bottles (although you're using glass bottle). cool it over night and bottling is done the next day. it requires time but no additional cost of
adding new ingredients or new machinery. just have a good plan of production and you're set to go! it is cost-free idea, you also could come up with an effective production plan

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Reply:

cold filling is not a good idea as contamination will occur in the process. The factory should maintain the hot filling technique and solve the viscosity problem in different way. The loss of viscosity is probably due to overcooking or with the quality of thickener.

DISCUSSION TO BE UPDATE...