Sugarcane juice was converted to ethanol by Saccharomyces cerevisiae producing 8% (v/v) ethanol. This ethanol was used for vinegar production using adsorbed (bagasse, corn cobs and wood shavings) and entrapped (calcium alginate) cells of Acetobacter aceti NRRL 746. All three adsorbed carrier materials were statistically similar for acetic acid production and produced acidity from 5.9 to 6.7% after 28 days of submerged fermentation. By recycling bagasse adsorbed cells, the time of acetic acid fermentation was reduced to 13 days. Semi-continuous fermentation of bagasse adsorbed cells using a packed bed column further reduced the fermentation time to 80 h.

The fermented tea vinegar combines the beneficial properties of tea and vinegar. The complete fermentation takes 4 to 5 weeks in a batch culture and thus can be shortened by semi continuous/ continuous fermentation using immobilized bacterial cells. In the present study, alcoholic fermentation of 1.0 and 1.5% tea infusions using Saccharomyces cerevisae G was carried out that resulted in 84.3 and 84.8% fermentation efficiency (FE) respectively. The batch vinegar fermentation of these wines with Acetobacter aceti NRRL 746 at the initial 1% acidity yielded 4.5 and 4.7% volatile acidity with 71.4 and 73% FE in 24 days. The semi continuous fermentation using sugarcane bagasse adsorbeded A.aceti cells produced 4.4% of volatile acidity from 1.5% tea wine (8.9% ethanol and 1.0% acidity), in 9 flow cycles, each of 4 h duration in a fermentation column at 50 ml/h. In the scale up process, 600 ml 1.5% tea wine produced 4.3% volatile acidity at 42.7% FE in 9 flow cycles of 12 h duration each.

Two local corn hybrid varieties PMH‐1 and PMH‐2 were evaluated for ethanol production. Corn flour (2.0 mm) was prepared and liquefied with about 3 KNU/g of starch and saccharified subsequently with Spirizyme. Spirizyme concentrations were optimized as 5 and 7 AGU/g of starch for PMH‐1 and PMH‐2 with saccharification levels of 81.1 and 85.6%, respectively. The ethanol production was maximum at 20% solids with yields of 0.45 and 0.52 g/g of starch for PMH‐1 and PMH‐2, respectively.

: The preparation of a fermented tea beverage from a Sri Lankan Broken Orange Pekoe (BOP) tea type is reported. The tea beverage was produced using 1–2.5% (w/v) Broken Orange Pekoe and was brewed using boiling sucrose sweetened (5–25°Brix) water (100°C for 3 min), followed by fermentation at 25°C, utilizing an 8.5% (v/v) inoculum of Saccharomyces cerevisiae G. A maximum ethanol of 14.91% (v/v) was obtained from an initial 25°Brix substrate with a 2.67°Brix drop per day. The tea beverage with an initial 15°Brix and 1.5% (w/v) tea yielded the best sensory score and was stable over a test period of 6 weeks at 15°C.

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