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• Fermentation


  The chemical changes in plant and animal matter caused by microorganisms
• Microorganisms in fermentation


  • Act on organic matter like starches, proteins, fats, and oils
  • Break down into simple substances with changes in tastes, smell, and odor
• Fermentation in food processing

  Conversion of sugar to alcohol using yeast under anaerobic conditions
• General definition of fermentation

  The chemical conversion of carbohydrates into alcohol or acid
• Food processing by fermentation

  Processing foods by means of special microorganisms acting on food constituents
• Fermentation end products of some microorganisms

  • Saccharomyces: ethyl alcohol and carbon dioxide
  • Streptococcus and lactobacillus: lactic acid
  • Propionibacterium: propionic acid, acetic acid, and carbon dioxide
  • Escherichia coli: acetic acid, lactic acid, succinic acid, ethyl alcohol, carbon dioxide, and hydrogen
  • Clostridium: butyric acid, butyl alcohol, acetone, isopropyl alcohol, carbon dioxide, and hydrogen
• Basic factors that affect fermentation


  • Input factor (raw materials/substrate)
  • Microbe
  • Process itself
• Alcohol fermentation


  Decomposition of simple sugars into alcohol and carbon dioxide
• Acetous fermentation


  Conversion of alcohol to acetic acid
• Lactic acid fermentation


  Fermentation of sugar by lactic acid bacteria producing lactic acid
• Fermented fish products

  • Patis
  • Nuoc nam
  • Nam pla
  • Liquamen
  • Garum
• Pickling


  Preserving foods in vinegar (or other acid)
• Two basic categories of pickling

  • Pickles preserved in vinegar
  • Pickling that involves soaking in a salt brine to encourage the growth of fermentative bacteria
• Four classes of pickling

  • Brined or cured pickles (fermented)
  • Fresh pack or unfermented pickles
  • Relishes, chutney and ketchup
  • Fruit Pickles
• Brined or cured pickles (fermented)

  Hold vegetables in a salt solution for several weeks until cured, using lactic acid from fermentation
• Fresh pack or unfermented pickles


  The vinegar in the recipe preserves the fruit or vegetable, using acetic acid from vinegar
• Relishes, chutney and ketchup

  Combine chopped or pureed vegetables or fruits with vinegar, salt, sugar and spices
• Fruit Pickles


  Whole or sliced fruit in a spicy sweet-sour syrup
• Ingredients for quick process pickles

  • Salt
  • Vinegar
  • Sweeteners
  • Spices
• Pickling solution formulation


  1 liter sweet-sour pickling solution is prepared by combining 445 grams refined sugar with 555 grams vinegar (4.5% acidity); while a sweet pickling solution is made with 500 grams sugar and 500 gram vinegar. A sour pickling solution is made with 350 grams sugar in 650 gram vinegar.
• Chutney


  A condiment made up of chopped fruits, vinegar, spices and sugar cooked in a chunky spread, traditionally served to complement curried foods
• Relish


  Usually chopped up crunchy pickled vegetables
• Problems in pickle making

  • Soft pickles
  • Slippery pickles
  • Slimy brine
  • Discoloration
  • Shriveled pickle
• Causes of problems in pickle making

  • Use of very weak brine during fermentation
  • Use of vinegar low in acidity
  • Exposure of the fermenting product to air
  • Scum formation and utilization of acid by the organism
  • Decomposition of pectin substances during the initial stage of fermentation
  • Development of bacteria during the fermentation in brine that are low in salt and acid content
  • Formation of iron sulfide as a result of using utensils made of iron
  • Pickles placed immediately in heavy syrup
  • Too strong brine
  • Too strong vinegar concentration
• Ways of preventing problems in pickles


  • Adequate washing
  • Use of properly cleaned and sanitized vats
  • Employment of the most suitable initial concentration of brine
  • Control of Scum (Film yeasts and molds)
• Characteristics of good quality pickles


  • Green coloring of vegetable turns to olive green or yellowish green, translucent, not chalky white or opaque
  • Uniform pieces of desired designs, firm or crisp, plump, and surrounded by clear pickling solution
  • Possesses a pleasing fermented flavor, not too salty, not too sour, not too sugary, or not too spicy
• Do's and Don'ts on pickling

  • Check your equipment
  • Work quickly to conserve freshness
  • Choose your method
  • Watch your timetable
  • Make sure vegetables are below the brine at all times
  • Preserve your pickles by proper pasteurization
• FERMENTATION

  •Fermentation refers to the chemical changes in plant and animal matter caused by microorganisms.

  •Those microorganisms act on such organic matter as starches, proteins, fats, and oils.

  •These materials are broken into simple substances with changes in tastes, smell, and odor.

  •In food processing, it typically refers to the conversion of sugar to alcohol using yeast under anaerobic conditions. A more general definition of fermentation is the chemical conversion of carbohydrates into alcohol or acid.

  •Processing foods by means of special microorganisms acting on food constituents
• Fermentation end product of some microorganisms:

  Saccharomyces: ethyl alcohol and carbon dioxide

  Streptococcus and lactobacillus: lactic acid

  Propionibacterium: propionic acid, acetic acid, and carbon dioxide

  Escherichia coli: acetic acid, lactic acid, succinic acid, ethyl alcohol, carbon dioxide, and hydrogen

  Clostridium: butyric acid, butyl alcohol, acetone, isopropyl alcohol, carbon dioxide, and hydrogen.
• Basic Factors That Affect Fermentation:

  1. Input factor (raw materials) which consists of the food commodity to be fermented called substrate.

  2. Microbe

  The most common groups of micro-organisms involved in food fermentations are:

  Bacteria

  Yeasts

  
  

  3. Process itself
• Alcohol fermentation

  •The decomposition of simple sugars into alcohol and carbon dioxide.

  •The sugar in the food is converted into ethyl alcohol through the reaction of yeasts at the appropriate temperature. The initial materials used for alcoholic fermentation are fruit juices and rice solution.
• Acetous Fermentation

  • The conversion of alcohol to acetic acid. Acetic acid bacteria (acetobacteria aceti) through the presence of abundant oxygen produces acetic acid, one of the more popular condiments
• Lactic Acid Fermentation

  • Lactic acid fermentation is brought about by certain bacteria which ferment sugar present in fruits and vegetables producing lactic acid. These bacteria are called lactic acid bacteria.

  Examples: sauerkraut, burong mustasa, yogurts
• Fermented Fish Products:

  1.Patis. Clear liquid that separates from the bagoong when this is allowed to ferment for 6 months or longer. It is carried out in concrete vats, earthen jars or wooden casks.

  It also exist in other countries as:

  -Nuoc nam in Vietnam

  -Nam pla in Thailand

  -Liquamen in ancient Rome

  -Garum in Greece

  2.Bagoong
• Pickling is preserving foods in vinegar (or other acid). On a most generic level, pickles are foods soaked in solutions that help prevent spoilage.
• Two basic categories of pickling:

  •Pickles preserved in vinegar, a strong acid on which few bacteria can survive.

  •Pickling that involves soaking in a salt brine to encourage the growth of fermentative bacteria that makes food less vulnerable to spoilage-causing bacteria. Common examples of fermented pickles are: kimchi, sauerkraut, cucumber dill pickles, burong mustasa, etc.
• Quick Process Pickles:

  Ingredients:

  •Salt. Use non-iodized pickling salt. Iodine may react with starches causing discoloration or darkening.
• Quick Process Pickles:

  Ingredients:

  Vinegar. Use vinegar with at least 4% acidity. Too low acidity will not preserve the vegetable. Use white vinegar for a lighter color vegetable such as ubod, singkamas, radish, onions and cauliflower.
• Quick Process Pickles:

  Ingredients:

  Sweeteners. White granulated and brown sugars are the sweeteners most often used in pickling. White sugar will not add any color to the product. However, brown sugar may add distinctive flavor and color.
• Quick Process Pickles:

  Ingredients:

  Spices. Pickling spices is a variety mix of whole spices. Common spices may include: coriander, cumin, mustard, peppercorns, dried hot peppers, cloves, bay leaf, and others.