Experiment No. 3 

Aim: To determine alcohol content from the marketed Arista formulation (Also calculate specific gravity, total solid content, PH) 

Reference: Government of India. (2008). The Ayurvedic Pharmacopoeia of India-Part-II. Vol II; First Edition, 2008, New Delhi, Page 209, 213-218. 


Requirement: specific gravity bottles, distillation assembly, marketed Arista formulation etc. 

Principle:  
Arista is a fermented product that accumulates alcohol by fermentation of sugar candy. The alcohol in these preparations facilitates the extraction of phytochemicals during fermentation and also acts as a preservative. The formation of alcohol depends upon the procedure adopted, the content of alcohol is present in limits.
The % alcohol in these formulations can be used as the basis of quality control. The alcohol content can be determined on the basis of specific gravity. The specific gravity of any solution depends upon the mixture of solvents or dissolved chemicals. There are standard known specific gravity of mixture of alcohol and water and can be used for analysis. The specific gravity of distillate of these formulations in a specified volume of water is used for alcohol 

Alcohol content (Method-I): 
1. Take 25 ml of the given marketed ayurvedic formulation, add 150 ml of water to it in distillation flask. 
2. Distillate the given mixture up to 90 ml of volume. 
3. Adjust the volume to 100 ml, allow it to cool at 24-25oC. 
4. Determined the specific gravity using a specific gravity bottle using alcoholometric table. 
5. Calculate the % alcohol content.

Alcohol content assembly

 

Procedure for Alcohol content (Method-II):

Transfer  25  ml  of  the  preparation,  accurately  measured  at  24.90   to  25.10 ,  to  the distillation  flask.  Dilute  with  150  ml  of  water  and  add  a  little  pumice  powder.  Attach  the distillation head and condenser. Distil and collect about 100 ml. Transfer to a separating funnel and determine the percentage v/v of ethanol. Determined the specific gravity using a specific gravity bottle using alcoholometric table. Calculate the % alcohol content.

Calculation:

Wt. of empty Specific gravity bottle (x)                   = 22.63 gm

Wt. of Specific gravity bottle with water (Y)            =  47.98 gm

Wt. of Specific gravity bottle + distillate alcohol (Z)  =  47.66 gm

                                                                                        =   0.9875


Specific gravity at 25

Ethanol content*

1.0000

0

0.9985

1

0.9970

2

0.9956

3

0.9941

4

0.9927

5

0.9914

6

0.9901

7

0.9888

8

0.9875

9

0.9862

10

0.9850

11

0.9838

12

0.9826

13

0.9814

14

0.9802

15

0.9790

16

0.9778

17

0.9767

18

0.9756

19

0.9744

20

0.9733

21

0.9721

22

0.9710

23

0.9698

24

0.9685

25

                                                        Alcohol content           =   9 ml

                                                    Hence  25 ml of Arista =  9 ml

                                                    100 ml  of Arista           =  ?

                                            =    36 % v/v

Specific gravity:

The specific gravity of liquid is wt. given liquid at specific temp. compared with the wt. of equal volume of water PH Same temp. all weight between taker in air.

Method: Take Specific gravity bottle of 25 ml capacity is clean dried & weight it in filled up to mark with water of required temp & weighed the specific gravity bottle wash then filled with sample up to mark & wt. of it by calculation get specific gravity by using formula.

Calculation:

Wt. of empty Specific gravity bottle (W1)                            = 22.71 gm

Wt. of Specific gravity bottle with water (W2)                    =  48.94 gm

Wt. of Specific gravity bottle + Sample (W3)                     =  51.20 gm

Wt. of water (W4),    W2-W1                                              =  26.23

Wt. of sample (W5),  W3- W2                                            =  28.49

Determination of Total Solids:

Determination  of  total  solids  in Aristha  is  generally  required.  Aristha containing sugar or honey should be examined by method 1, sugar or honey free Aristha and other material should be examined by method 2.

 

Method  1:  Transfer  accurately  50  ml  of  the  clear  Aristha  an  evaporable  dish  and evaporate to a thick extract on a water bath. Unless specified otherwise, extract the residue with 4 quantities, each of 10 ml, of dehydrated ethanol with stirring and filter. Combine the filtrates to another evaporating dish which have been dried to a constant weight and evaporate nearly to dryness on a water bath, add accurately 1 g of diatomite (dry at 1050  for 3 hours and cooled in a desiccator for 30 min), stir thoroughly, dry at 1050  for 3 hours, cool the dish in a desiccator for 30  min,  and  weigh  immediately.  Deduct  the  weight  of  diatomite  added,  the  weight  of  residue should comply with the requirements stated under the individual monograph.

 

Method 2: Transfer accurately 50 ml of the clear Asava/ Aristha to an evaporable dish, which has been dried to a constant weight and evaporate to dryness on a water bath, then dry at 1050 for  3  hours.  After  cooling  the  dish  containing  the  residue  in  a  desiccator  for  30  min,  weigh  it immediately.  The  weight  of  residue  should  comply  with  the  requirements  stated  under  the individual monograph.

Calculation for total Solid content:

Wt. of empty petridish                                   =   64.67 gm

Wt. of petridish + Liquid after ignition        =  73.98 gm

Wt. of residue                                               =  65.30 – 64.67  =   0.63 gm

Wt. of liquid                                                 =  73.98  - 64.67  =  9.31 gm