Fermented Coconut and Palm Sap Products

Fermented Coconut Sap Products: Substrates and Starter

Culture• Products: nata de coco, vinegar, tuba, lambanog• Substrates: coconut sap/water/milk, nipa sap,

kaong sap, and buri sap

STARTER MICROORGANISMS

Nata de coco Glucoacetobacter xylinus (formerly Acetobacter xylinum)

Vinegar – Acetobacter spp. and Gluconobacter spp.

Tuba – Saccharomyces cerevisiae, other Saccharomyces species; LAB and AAB

Lambanog bubod, a mixed microflora of molds, yeasts and bacteria

Nata de Coco• A chewy, translucent, jellylike foodstuff produced

by the fermentation of coconut water by acetic acid bacteria specifically Gluconacetobacter xylinus

• “Nata” is a Spanish word derived from the Latin word natare” meaning “to float”

• Highly regarded for its high

dietary fiber, low fat content,

and zero cholesterol content• Was started in Pagsanjan, Laguna

from juice of pineapple parings

used in bleaching pinya cloth

Nata de Coco Production• Extraction of coconut water• Fermentation of coconut water with a bacterial

culture• Separation and cutting of the produced mat of

nata de coco• Cleaning and washing off the acetic acid

produced• Cutting and packaging

Vinegar• Product of the alcoholic fermentation

of starchy or saccharine materials followed by the acetification of the fermented liquor by acetic acid bacteria

• Acetic acid produced by the bacterial fermentation of ethanol

• Now mainly used as a cooking ingredient for flavoring and preserving food, but historically as the most easily available mild acid for industrial, medical and domestic uses

Etymology

• From the French words meaning wine vin

and aigre meaning sour

So vinegar is simply

“SOUR WINE”

Chemical Process of Vinegar Production

1. Fermentation of sugar to ethanol

2. Partial oxidation of ethanol to acetaldehyde

3. Conversion of acetaldehyde to acetic acid

(acetification)

yeast

CHO CH3CH2OH 2 HCH3CHO 2 CH3COOH

acetic acid bacteria

Points in Vinegar Production1. Alcoholic fermentation

• Favorable temperature: 24-27°C• Best to add yeast as a starter culture• Generates an anaerobic or partially

anaerobic environment to produce alcohol• Normal fermentation period: 7-10 days• Optimum alcohol content: 10-13%

2. Acetification• Right strain of acetic acid bacteria• Right choice of raw materials• Acidity of the substrate should not exceed

pH 5.0• Generates an aerobic condition

Methods of Vinegar Production

1. Natural or spontaneous fermentation• Occurs in nature• Requires no culture inoculation• Substrate undergoes simultaneous

alcoholic fermentation followed by natural acetate fermentation

2. French Orleans process• Also called the continuous method• Fresh alcoholic substrate is added to bring

the volume to ~1/2 of the barrel and acidified with fresh vinegar

• Under aerobic condition, Acetobacter spp. grow as a thin film on the surface of the alcoholic substrate and oxidize ethanol to acetate. As the substrate turns to vinegar, it is withdrawn and fresh alcoholic liquor is added.

3. Submerged fermentation method• Commonly used in wine vinegar production• Requires the use of large stainless steel

tanks called acetators, which are fitted with centrifugal pumps at the bottom for pumping air bubbles. As the bubbles stir the alcohol, acetozym nutrients are piped into the tank, spurring the growth of acetobacter species on the oxygen bubbles, which convert the alcohol to vinegar, which is then piped to a filtering machine and then to a dilution station.

• Tank temperature: 26-38°C

4. Highly sophisticated rapid vinegar fermentation

• Use of Fring’s generator, which has automatic controls for temperature, aeration, and recirculation of substrate

• A fine mist of Acetobacter and alcoholic solutions are sprayed

into the chamber until

ethanol is completely

oxidized to acetate.

Kinds of Vinegar1. Cider vinegar - from apple juice

2. Wine vinegar - from wine

3. Balsamic vinegar - from Trebbiano and Lambrusco grapes

4. Malt vinegar - from barley malt or cereals

5. Sugar vinegar - from sugar syrup, molasses, or refined sugar

6. Glucose vinegar - from glucose solution

7. Spirit/distilled/grain vinegar - from dilute distilled alcohol (by acetous fermentation)

Philippine Vinegar

• Substrates: fruit juices (particularly pineapple), sugar cane, coconut water, nipa, buri, and kaong sap

• Uses: condiment, for manufacture of pickles, tomato catsup, chili sauces, and sauces for canning fish.

Coconut Water

• Low sugar content, thus sugar is adjusted to 15 Brix to produce ~7.5% alcohol v/v and ~6% vinegar

• Vinegar fermentation requires 7-10 days, plus acetification of 2-3 weeks.

Coconut/Palm Sap Vinegar

• A cloudy white liquid with a particularly sharp, acidic taste with a slightly yeasty note

• Produced by collecting palm sap and placing it in earthen jars, allowing it to ferment spontaneously

• Used extensively in Southeast Asian cuisine

Iloko Vinegar (Sukang Iloko) • Prepared from sugarcane wine (basi)• Fermentation requires a year; final acidity of

vinegar is 6% and has excellent quality• Dark yellow to golden brown; has a mellow

flavor similar to

rice vinegar• Has no residual

sugar• Often labeled as

“sukang maasim”

Quality ControlGrowing Acetobacter spp. requires vigilance. • In the Orleans method, bungholes must be

routinely checked to ensure that insects have not penetrated the netting.

• In the generator method, great care is taken to keep the temperature inside the tank in the 26-38°C range. Thermostats on the tanks are routinely checked.

• Because a loss of electricity can kill Acetobacter spp. within seconds, many vinegar plants have backup systems to generate electric power in the event of a blackout.