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The study on “Process standardisation for banana wine” was undertaken to evaluate the physico chemical and sensory qualities of banana (Palayankodan) wines with pure strains of wine yeast Saccharomyces cerevisiae and commercial baker’s yeast. Since, composition and quality of a wine was closely related to the yeast strain used, standardisation of banana wines with yeast strains was an objective of the study.

In the present study, three pure strains of Saccharomyces cerevisiae viz MTCC 172, MTCC 174 and MTCC180 were obtained from IMTECH and the commercial baker’s yeast were used each in two different dilutions (106 and 107) for fermentation of banana pulp. Inoculum concentration was standardised by standard procedures before fermentation. Wine yield was significantly high with baker’s yeast in both 106 dilution (68.36%) and 107 dilution (67.76%). Among pure strains, wine yield was high with MTCC 172 in both dilutions (59.53 and 57.57% respectively). MTCC 172 (106) also produced wines with significantly high TSS (13.93° brix) and high pH (4.25). Among wines with baker’s yeast, T7 (106 dilution) showed highest wine yield (68.36%), alcohol content (8.23%) and TSS (12.46° brix) with a corresponding high titrable acidity of 0.89 per cent and low pH (3.74). Clarity of wine was maximum (T8) with baker’s yeast (78.75% light transmittance) in 107 dilution. Sensory qualities of the wines with yeast strains revealed that the panelists were in agreement only with the high flavour profile of the wines. Among pure strain, MTCC 172 (106) dilution had the maximum score for colour and appearance (8.1), flavour (8.1), taste (7.9) and overall acceptability (7.8). Among wines with baker’s yeast, T7 (106 dilution) showed the best score for colour and appearance (8.4), flavour (8.2) and overall acceptability (7.6).

Based on the overall acceptability score of the wines, pure strain MTCC 172 (106 dilution) and baker’s yeast in 106 dilutions were selected for wine development.

Another objective of the study was to evaluate the effect of various treatments on the quality attributes of wines developed by the selected yeast strains. Treatments with pectinase enzyme, potassium metabisulphite (KMS) and pressure cooking of banana pulp as a pretreatment were done to evaluate the quality aspects of wines.

Among treatments with MTCC 172, T2 (pulp + sugar + PS + enzyme) and T8 (pressure cooked pulp + sugar + PS + enzyme + KMS) were selected with maximum overall acceptability score (7.9). Among treatments with baker’s yeast, the selected treatments with acceptable quality parameters were T2 (pulp + sugar + BY + enzyme) and T4 (pulp + sugar + BY + enzyme + KMS) with the highest overall acceptability score of 7.8 and 7.7 respectively.

All the four selected wines were treated with pectinase (0.3%).

The selected wines after initial quality evaluation were pasteurised and bottled in amber coloured bottles with cork caps and were stored in ambient temperature for three months for storage studies. The physico chemical characteristics of the wines showed a significant increase in clarity, titrable acidity, tannin and a significant reduction in reducing sugar. Maximum wine clarity, titrable acidity and maximum reduction in reducing sugar were found in T2PS.

With respect to organoleptic qualities, there was no significant change with regard to colour and appearance, taste and overall acceptability of the wines in storage. A significant increase in flavour, desirable level of astringency and acceptable level of alcohol were observed in T2PS (pulp + sugar + PS + enzyme) after storage.

Organoleptic qualities after storage revealed a high score for T2PS in attributes like desirable level of astringency (7.9), sugar acid blend (8.1), taste (8.2), acceptable level of alcohol strength (8.0) and overall acceptability (8.1).

After storage there was no microbial population (yeast, bacteria and fungi) in the wines.
The cost of production of the selected wine treatment T2PS (pulp + sugar + PS + enzyme) was worked out and was compared with the cost of 750 ml of grape wine locally available made by wine makers. Grape wine (750 ml) costs Rs.150/- whereas the banana wine costs Rs. 96/-. The cost can be reduced further in large scale production of banana (Palayankodan) wines