Introduction
Yeasts ( Saccharomyces cerevisiae) are important eukaryotic micro-organism , having range of application such as fermentation, baking and bioremediation. Nutrient cell content of yeasts known as ‘Yeast extract ‘ is extensively used as nutritional resource in bacterial culture media.
Importance of Project
Regardless of availability of numerous commercial yeast extracts for preparation of microbial culture media , a simple method for preparing the high quality yeast extract will be of great benefits.
My aim in ongoing project is to produce a rapid ,simple and cost benefit process to produce yeast extract.
Objectives
Isolation of yeast from yoghurt for Yeast Extract production.
Protocol
1. Preparing yeast suspension through serial dilutionTake 10 ml yoghurt transfer it into 90 ml 0.1% of sterile peptone solution (100 mg peptone into 99ml of distilled water)
2, Transfer 1ml of solution into 9ml of 0.1% peptone solution by using pippete
3 .Repeat this procedure for three times and prepare dilutions of 10-1 , 10-2, 10-3 and 10-4
PLATE NO. 1 : SERIAL DILUTION
4. Strike the suspension on respective nutrient media , here used YEPD Agar Media for yeast colony growth.
5. Use small amount of inoculum by using nichrome loop for striking ( four quadrant method).
6. Make sure that the surface of plate is free from moisture droplet.
- Principles of the Procedure
YPD Agar and YPD Broth contain peptone as a source of carbon, nitrogen, vitamins and minerals. Yeast extract supplies
B-complex vitamins which stimulate bacterial growth. Dextrose is the carbohydrate source. YPD Agar contains agar as the solidifying agent.
TABLE NO. 1: YEPD COMPOSITION
PLATE NO 2 : COLONIES OF YEAST
7. Single colony of yeast from plate transfer into YEPD BROTH using loop .
8. Multiplication of cells done by giving continous agitation to broth using rotatry shaker to collect pure culture.
PLATE NO.3: YEPD BROTH WITH PURE CULTURE
Bread from Yeast Extract
Material
TABLE NO :2 – INGREDIENTS FOR BREAD MAKING
|
Sr.No |
Ingredients |
Quantity for 7kg |
Quantity for ½ kg |
|
1 |
Maida |
7 kg |
½ kg |
|
2 |
Yeast |
150 gm |
10.5 gm |
|
3 |
Sugar |
75 gm |
5.5 gm |
|
4 |
Salt |
150 gm |
10.5 gm |
|
5 |
Oil |
100 gm |
10 gm |
|
6 |
Bread Improver |
14 gm |
1 gm |
Procedure for Bread making
1. Take Maida , Sugar and Bread improver in a bowl , add warm water in batter and kept it for 10 min
2. Seived the refined wheat flour. Add salt in it mixed well
3. Add the batter into flour and mixed well
4. Kneading by using water
5. Fermentation proofing for an hour
PLATE NO 4 : BREAD PREPARATION
COSTING
Reference
Outcome
