Pipette 100 ml of the wine sample into a 500 ml distillation flask, add 50 nil water, and a few...

Question

Pipette 100 ml of the wine sample into a 500 ml distillation flask, add 50 nil water, and a few boiling chips (3 chips are required). Attach the distillation flask to a condenser fitted with a receiver adaptor which reaches into a clean 100 ml volumetric flask, the receiving flask should stand in a vessel of cold water. Distil about 90 ml of liquid at a uniform rate, taking 30-60 minutes. Make up the volume to 100 ml with distilled water.Determine the concentration of ethanol in the distillate (and hence in the sample) from measurements of refractive index.
	
Document Preview: 10
EXPERIMENT 1
ALCOHOL CONTENT OF VYINE
goggles'
Hazard Warning: Wear appropriate gloves, protective eyeglasses or chemical safety 
protective 
and clothing.
Ethanol is flammable
INTRODUCTION (Two 
students work together)
of a
A standard method for the determination of ethanol in beverages involves the distillation 
quantitatively in the
sample, which has been diluted with water. The ethanol is recovered virtually 
ethanol concentration
distillate; since the distillate is essentially a mixture of ethanol and water, the 
can be determined physical measurements or refractive index.
by simple such as density 
EXPERIMENTAL
techniques,
NOTE: To construct distillation system, please consult Appendices/ Experimental 
appendices 1 purification by distillation
Pipette 100 ml of the wine sample into a 500 ml distillation flask, add 50 ml water, and a few
a
boiling chips (3 chips are required). Attach the distillation flask to a condenser fitted with 
receiver adaptor which reaches into a clean 100 ml volumetric flask, the receiving flask shouid
taking 30-60 minutes.
stand in a vessel of cold water. Distil about 90 ml of liquid at a uniform rate, 
Make up the volume to 100 ml with distilled water.
Determine the concentration of ethanol in the distillate (and hence in the sample) from
measurements of refractive index.
CALCULATIONS
Extensive index aqueous ethanol solutions
tables relating ethanol concentration to the refractive of 
may be found in the AOAC Methods of Analysis (available in laboratory).
ASSESSMENT
Show your practical book (to containing the refractive index measurement and the
be signed) 
alcohol content to your demonstrator at the end of the session.
marking
Next week typed or clear hand written report should be summit to the demonstrator for 
REFERENCES
1. Horwitz (ed.), Official methods of analysis of the A.O.A.C., 12th edition I97 5.
, 
2. Distillation (see 
notes Appendix).
3. Refractive (see 
Index notes Appendix).

Robert · Accepted Answer

DETRMINATION OF ALCOHOL CONTENT OF RED WINE USING 
REFRACTOMETRY 
ABSTRACT:  
Red wine is a type of wine usually made from black or other dark colour grape 
varieties.  Its production involves various steps like grape processing, destemming 
and crushing, preparation of the must, cooling of the must, inoculation, fermentation, 
pressing, racking and aging of wine. During this process, strict quality control need to 
be ensured in different stages, especially during the final stages, where the amount 
of alcohol in the wine is very important.  There are many physical and chemical 
methods to determine the alcohol content of the wine.  Use of refractometer is a 
simple and easy method to determine the alcohol content. Direct estimation of 
alcohol is not possible. Instead, it is distilled to get the alcohol portion out and its 
refractive index is measured and compared with the standard tables available to find 
alcohol percentage. 
INTRODUCTION 
Red wine is a common alcoholic beverage using throughout the globe in all 
occasions and social gatherings. Hence the quality control if this undistilled beverage 
cannot be compromised at any cost. As it is contain alcohol, ethyl alcohol, it is very 
important that the proper percentage of alcohol is maintained in the bottle 
commercially available. Being an undistilled alcoholic beverage, where alcohol is not 
present in the pure form, to find the exact amount of alcohol,

Pipette 100 ml of the wine sample into a 500 ml distillation flask, add 50 nil water, and a few boiling chips (3 chips are required). Attach the distillation flask to a condenser fitted with a...

Solution

Answer To This Question Is Available To Download

Related Questions & Answers

Submit New Assignment