Etiket Arşivleri: acetic acid
1. How would you determine if a zone of inhibition was due to the bacteriocidal (killing) or bacteriostatic (growth inhibiting) action of an antimicrobial?
2. Sometimes, one observes a few bacterial colonies growing within a zone of inhibition. How would you explain this? How would you conclusively prove your hypothesis?
3. How do antibiotics differ from other natural products of microbes such as lactic acid, acetic acid, ethanol and others?
4. How are new antibiotics discovered? What properties must they possess in order to be more desirable than previously discovered antibiotics?
These can be made in a day or two in contrast to those that are fermented or brined and cured,a long-term process.In this process, it is important to use a good quality, clear, commercially prepared vinegar that is free from sediment with five percent acetic acid. Home-made vinegar should not be used.Distilled white vinegar helps keep the original color, while cider, wine or malt vinegar may slightly darken the food.Because the vinegar is part of the preservationprocess, it is important not to vary the amount recommended in the recipe. Use reliable, up-todate recipes.
Be creative in pickling fruits and vegetables.Feel free to add or omit herbs and spices, but do not alter the basic ingredients. The ratio of vinegar to vegetables is determined in recipes to insure their safety and quality.In this quick vinegar method, the fruit or vegetables are usually packed into jars, then covered with a hot vinegar solution. They are generally processed in a simmering hot water bath of 170 to 180°F. Some pickled foods can be safely open-kettle canned. Open-kettle canning,however, does contribute to a higher rate of spoilage and seal failures and is therefore not recommended.
VINEGAR MAKING Acetic acid
Vinegar Legally means acetic acid product made from apples ( like wine is from grapes) To be legal, vinegars in US must contain a minimum of 4% of acetic acid
Different countries Different countries
-different starting different starting materials materials
Continental Europe -grape wines
Great Britain – malt
Hawaii and Far East – pineapple pineapple
IMITATION VINEGAR IMITATION VINEGAR
In late 1800s chemist learned how to In late 1800s chemist learned how to make acetic acid make acetic acid Manufacturers added water to reduce Manufacturers added water to reduce strength to 5%, colored it and sold is as a strength to 5%, colored it and sold is as a vinegar vinegar Imitation vinegar is still manufactured and Imitation vinegar is still manufactured and by law the label must state that is diluted by law the label must state that is diluted acetic acid acetic acid