problem statement:

"Decreasing weight loss in food items in vacuum cooling system"

Description:

Concerned about product quality & safety, advancement in technology has brought the vacuum cooling technique that increases the life of food through the evaporative cooling phenomenon. Processing time, energy-saving, product shelf life, quality and safety of food have improved a lot in all these years and have encouraged many food manufacturers to further use this. 

But certain factors resist it's usage among many, be it in terms of its cost or efficiency. 

Some major limitations are the high initial investment in equipment, uneven cooling in some leafy vegetables and weight loss due to moisture loss.

Loss of water vapour affects the food quality factors such as texture, colour and perceived product characteristics. We will try to mitigate the weight loss in food items kept in vacuum cooling system, so that food quality can be preserved efficiently.

For the first week, we looked into the disadvantages of vacuum cooling technology.

Vacuum cooling is achieved through water evaporation, so that this process mostly used for porous structure product containing free water. during vacuum cooling process, we have to take care of amount of moisture loss due to evaporation should not cause significant deterioration to product quality.

Now, this process rapidly loses water, due to which the yield also decreases. And decreasing yield adversely affects the manufacturers since yield is directly related to profit.

We also found that vacuum cooling process has successfully employed on lettuce, cabbage, mushroom etc. But it has been unsuccessful for oranges, tomatoes and apples unless peeled.

Now for the upcoming week, we are going to look into xyz.

Citation Link: abc.com

For the first week, we looked into the disadvantages of vacuum cooling technology.

Vacuum cooling is achieved through water evaporation, so that this process mostly used for porous structure products containing free water. during vacuum cooling process we have to take care of amount of moisture loss due to evaporation should not cause significant deterioration to product quality.

Now, this process rapidly loses water, due to which the yield also decreases. and decreasing yield adversely affects the manufacturers since yield is directly related to profit. We also found that vacuum cooling process has successfully employed on lettuce, cabbage, mushroom etc. But it has been unsuccessful for oranges, tomatoes and apples unless peeled.

Now, for the upcoming week, we are going to look into factors affecting temperature reduction and weight loss in vacuum cooled lettuce.

Citation Link: https://www.sciencedirect.com/science/article/abs/pii/S0260877405004310

What is vacuum cooling process??

This process works on principle of rapid evaporation of moisture from the surface. Firstly, we have to create vacuum by removing air by using vacuum pump from vacuum chamber. We know that the temperature at which water starts to evaporate is directly depends on the surrounding vapour pressure. In vaccum, vapour pressure is very less so that boiling point of product is also reduces that's why free water within the products easily start to evaporate. And this vapour is condensed in condenser using coolent and leave through drainage.

Advantages:

1: exceptionally fast cooling rate

2: shorten processing time

3: extend product shelf life

4: improve product quality as well as safety

Applications:

Used in vagetables and fruits,  also used in bakery products and viscous food products, fishery products and cooked meats for extend shelf life and improve product quality and also used for extend life of vase

Now, in second week, we looked into the factors affecting temperature reduction and weight loss and we got some rough ideas about reducing weight loss in leafy vegetables like lettuce, cabbage etc. 

The factors are, initial temperature of products, time in the vacuum tank, speed of tank evacuation, tank pressure, condenser temperature, free moisture in products, packaging materials and maturity of products.

From these factors, we saw that weight loss directly depends on the initial temperature of the products. Therefore, we can reduce the weight loss by controlling initial temperature of products.

We also saw that, in some leafy vegetables ( like lettuce, cabbage, cauliflower, spinach ), we can reduce weight loss by spraying water onto these products and thereafter covering them with perforated PVC film before cooling in the vacuum cooled environment.

Now, for upcoming week, we are going to find out solutions for reducing weight loss in different products in vacuum cooling process. We'll also look for ways to make this process more economical.

Citation Link:

1) https://scialert.net/fulltextmobile/?doi=jas.2006.2031.2035

2) https://hortscans.ces.ncsu.edu/uploads/f/a/factors__51ba16284b2a6.pdf

Concerned about the moisture content in different food products, during the third week we analysed the same.

We know that moisture content in food items is responsible for it's taste, texture, appearance and weight. The shelf life of the products, food quality, freshness, resistance to bacterial contamination all these factors are affected by the moisture content. So it is essential to get an idea about moisture content in different food products.

Moisture content is considered as the number of water molecules in food items. Excess amount of moisture in food items can cause an increase microbial growth rate, which can not only spoil a product but could also decrease the freshness time of products. Very less amount of moisture in food items adversely affect the food quality factors. So it is essential to think about moisture content.

Moisture content analysis so done for various products are:

1) fruits and vegetables: more than 90%

2) Meat products : 60-75%

3) Bakery products like bread : 35-45% , cake : 15-30% , biscuits : 1-5%

Now, for upcoming week, we are going to get some ideas about vacuum cooling in Bakery products. 

Citation link:

https://www.news-medical.net/life-sciences/Why-is-Moisture-Content-Analysis-of-Food-Important.aspx

With the progress of our research we further looked into the vacuum cooling process in bakery products and also got ideas for reducing weight loss.

Vacuum cooling is widely using in a bakery industry due to following advantages: decreased cooling time, lower risk of post bake mold contamination, less space required for equipment, product remains crusty to reduce chance of collapse during slicing, safe etc.

The exceptionally high cooling speed of this process makes it more attractive and more adoptable. The uniqueness of this process is that it doesn't depend on the atmospheric conditions, so we can achieve consistent result all the time.

Baked bread, bread rolls and loaves, pastry, pizza etc. are the examples of bakery products in which vacuum cooling can be used.

Besides all these applications and advantages, the main problem in vacuum cooling in bakery industry is that weight loss due to loss of moisture. We can overcome this limitation by shortening the baking time ( this process saves water in the system, so that weight loss can be reduced). In case of bread, by adding baking agent as a PF (potato flour), HPMC (hydroxypropyl methyl cellulose) and honey, we can reduce the weight loss as this agent increases water holding capacity of bread.

Weber cooling (Netherlands) is a big example of vacuum cooling in all applications  including bakery industry.

For upcoming week, we are going to study hydro-vac system, which is more important technique for reducing weight loss.

Citation link :

1)https://www.researchgate.net/publication/236189199_Baking_loss_of_bread_with_special_emphasis_on_increasing_water_holding_capacity

2)https://bakerpedia.com/processes/vacuum-cooling/

3) Weber cooling:

https://webercooling.com/en/vacuum-cooling-process

For this week, we studied hydrovac technique for reducing weight loss.

We saw that, the biggest problem in vacuum cooling process is weight loss due to loss of moisture. The average moisture loss is one percent for each eleven degree Fahrenheit temperature drop. Larger weight loss directly affect the quality of product whether it is a vegetables, bakery products or anything else. and we also know that this kind of food items are sold by weight, so it is essential to maintain the weight loss.

So for reducing weight loss, there is a one technique, that is hydrovac technique which can help to decrease the weight loss by spraying clean water on a given product during the vacuum cooling operation. This technique is activated towards the end of the vacuum cooling operation. So that weight loss can be decrease by maintaining moisture in a product.

Now, for upcoming week, we are going to find out ways for making this process economical.

Citation link :https://southernvacuumcooling.com/the-process/

With the progress of our research we further looked into the vacuum cooling process in bakery products and also got ideas for reducing weight loss.

Vacuum cooling is widely using in a bakery industry due to following advantages: decreased cooling time, lower risk of post bake mold contamination, less space required for equipment, product remains crusty to reduce chance of collapse during slicing, safe etc.

The exceptionally high cooling speed of this process makes it more attractive and more adoptable. The uniqueness of this process is that it doesn't depend on the atmospheric conditions, so we can achieve consistent result all the time.

Baked bread, bread rolls and loaves, pastry, pizza etc. are the examples of bakery products in which vacuum cooling can be used.

Besides all these applications and advantages, the main problem in vacuum cooling in bakery industry is that weight loss due to loss of moisture. We can overcome this limitation by shortening the baking time ( this process saves water in the system, so that weight loss can be reduced). In case of bread, by adding baking agent as a PF (potato flour), HPMC (hydroxypropyl methyl cellulose) and honey, we can reduce the weight loss as this agent increases water holding capacity of bread.

For upcoming week, we are going to study hydro-vac system, which is more important technique for reducing weight loss.

Citation link :

1) https://www.researchgate.net/publication/236189199_Baking_loss_of_bread_with_special_emphasis_on_increasing_water_holding_capacity

2)https://bakerpedia.com/processes/vacuum-cooling/

Concerned about product quality & safety, advancement in technology has brought the vacuum cooling technique that increases the life of food through the evaporative cooling phenomenon. Processing time, energy-saving, product shelf life, quality and safety of food have improved a lot in all these years and have encouraged many food manufacturers to further use this. 

But certain factors resist it's usage among many, be it in terms of its cost or efficiency. 

Some major limitations are the high initial investment in equipment, uneven cooling in some leafy vegetables and weight loss due to moisture loss.

Loss of water vapour affects the food quality factors such as texture, colour and perceived product characteristics. We will try to mitigate the weight loss in food items kept in vacuum cooling system, so that food quality can be preserved efficiently.