Preparation of raw materials
In gathering the fruits and transporting them to the workshop, the prime purpose should be to have the fruit arrive in the very best condition possible. Cashew apples are sorted and only mature undamaged cashew apples should be selected. These should be washed in clean water.
The cashew apples are cut into slices to ensure a rapid rate of juice extraction when crushed in a juice press. The fruit juice is sterilised in stainless steel pans at a temperature of 85oC in order to eliminate wild yeast. The juice is filtered and treated either sodium or potassium metabisulphite to destroy or inhibit the growth of any undesirable types of micro-organisms – acetic acid bacteria, wild yeasts and moulds.
Wine yeast (Saccharomyees cerevisiae – var ellipsoideus) are added. Once the yeast is added, the contents are stirred well and allowed to ferment for about two weeks.
The wine is separated from the sediment. It is clarified by using fining agents such as gelatin, pectin or casein which are mixed with the wine. Filtration is carried out with filter-aids such as fullers earth. The filtered wine is transferred to wooden vats.
The wine is then pasteurised at 50o – 60oC. Temperature should be controlled, so as not to heat it to about 70oC, since its alcohol content would vaporise at a temperature of 75o-78oC. It is then stored in wooden vats and subjected to ageing. At least six months should be allowed for ageing.
If necessary, wine is again clarified prior to bottling. During ageing, and subsequent maturing in bottles many reactions, including oxidation, occur with the formation of traces of esters and aldehydes., which together with the tannin and acids already present enhance the taste, aroma and preservative properties of the wine (Wimalsiri, Sinnatamby, Samaranayake and Samarsinghe, 1971).
by Mr. Mike Battcock and Dr. Sue Azam-Ali,(fao)
Measure the following physico-chemical properties and and adjust accordingly to your set standard. Properties should be uniform every batch.
a. sugar content. Sugar concentration can be increased by adding sugar or can be lowered by adding water or pulp.
b. pH. This can be lowered by adding citric acid or can be increased by adding water or pulp.
c. titrable acidity. Adjustment can be made by mixing different concentrations or addition of citric acid.
d. alcohol content. Adjustment can be made by mixing different concentrations.
Adjustments can be computed using Pearson’s Square formula.
e. See standards for wine here.