EXPERİMENT 3

BOZA PRODUCTION

Introduction

Boza is a traditional cereal-based fermented cold drink with a slightly acidic sweet flavour. This beverage originated in Mesopotamia 8000-9000 years ago. Boza is mainly made from hulled millet, which is boiled in water and then poured into broad shallow pans. When cool, the mixture is sieved, and water and sugar are added. Boza is produced in most Turkish regions as well as in Bulgaria, Albania and Romania. Different cereals (wheat, millet and rye) can be used for Boza production, and natural mixtures of yeasts and lactic acid bacteria cause fermentation. In Boza production both lactic acid and alcohol fermentation would proceed.

The role of lactic acid bacteria in Boza production is lowering pH due to production of lactic acid LAB’s also produce CO₂, asetaldehyde, hydrojenperoksit, diacetyl ve amino asit which give aroma compounds and protect the Boza.

The role of yeast in Boza fermentation is support the LAB growth. Yeast synthesis the growth factor. Also in Yeast fermentation, ethyl alcohol and CO₂ are released. By the help of CO₂ the Boza volume are increased.

Equipment

2 piece 500 ml container, sifter,  water bath, mixer/ spoon

Materials

Corn, wheat and rice, sugar, 0.1 M NaOH, starter culture (or yoğurt, boza)

Boza Production Process

Raw materials- Flours (maize, whole wheat and rice) (2:1:1)

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Mixing

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Boiling (40 min)

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Cooling

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Add Water (2 times the mixture weight (v/w))

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Sweetening- Add sugar (20% w/v)

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Mixing

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Inoculation of starter culture (2% v/v)

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Fermentation

Procedure

First of all, maize, whole wheat, and rice flours were mixed in the ratio of 2:1:1, respectively. One liter of water was incorporated into the flour mixture and the mixture was heated on a medium heating system with continuous stirring for 40 min. Because the mixture absorbed the water, hot water (4 times the total flour weight (v/w)) was incorporated into the mixture during the heating process. Afterwards, the final mixture was cooled at 4 °C for 2 to 12 h and tap water (2 times the mixture weight (v/w)) was added commensurately. Sugar (20% w/w) was added and stirred in. Finally the mixture was filtered by a sifter to remove the ungelatinized parts of the boza wort. Boza wort was divided into 2 lots (500 mL each) in sterile volumetric flasks and starter cultures (or yogurt, boza as starter culture) were inoculated into each lot at 2% (v/v) concentrations  After inoculation of starter culture, the final boza samples were incubated at 30 °C for 24 h.

FE 211 25.10.2004

EXPERIMENT 3

LAB REPORT

Submitted By : Mutlu DEMİREL Group: 3

MATERIALS:

0.1 M NaOH , Potassium Hydrogen Phthalate , Desiccator , Phenolphthalein , 5 ml Vineger , Distilled water , Flask , Buret , Erlenmayer Flask

PURPOSE:

In this experiment our aim is to determine the molarity of NaOH and weight percentage of with neutralization titration.

METHOD:

Gravimetric Analysis

THEORY:

Both NaOH and HCl are frequently used reagents: the former an example of a strong base, and the latter an example of a strong acid. This classification comes from the position of the equilibrium when each is placed in an aqueous solution:

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