Fermented cereal products 2

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Fermented Cereal ProductsBread

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Bread• A staple food prepared from a dough of flour and

water, usually by baking --- Wikipedia

• Food made of flour, water, and yeast or another leavening agent, mixed together and baked --- Google

• A staple food made from flour or meal mixed with other dry and liquid ingredients, usually combined with a leavening agent, and kneaded, shaped into loaves, and baked. --- Thefreedictionary

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Manufacturing Process

Mixing and kneading the dough Fermentation Cutting, "resting" and gas reproduction Molding Baking Slicing Packaging

Fermentation

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Yeast Lactic acid bacteria

Saccharomyces cerevisiae Leuconostoc mesentoroides

In breadmaking, fermentation involves two microorganisms

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Roles of Yeast

Increases dough volume Develops structure and texture Imparts distinctive flavor to the bread Enhances the nutritive

value of the product

Roles of Lactic Acid Bacteria

Produce lactic acid Produce flavoring compounds

BREADMAKING

Microorganisms involved Saccharomyces cerevisiae Leuconostoc mesenteroides

Leavening is performed by yeast Longer fermentation will produce more

acids, resulting in a tendency of dough collapse

During fermentation, dough "conditioning" takes place. Conditioning is a result of the action of gluten induced by the following:

a. proteolytic enzymes

b. pH reduction due to acid production

Dough Conditioners

Ammonium salts, which are sometimes used to stimulate the yeast

Sugars, which are usually added in the formulation for activity of yeast

NOTESThe rate of gas production by yeast can be increased by the addition of the following: More yeast Sugar or amylase-bearing malt Yeast food

On the other hand, gas production is decreased by the following: Salt addition Addition of too much yeast food Use of too high or too low a temperature

Production Steps

• (see separate handout about bread making)• Additional notes about Baking Step

Fermented Rice CakePUTO

Generally served with grated coconutBreakfast and snack foodTypes: plain and special

a leavened, steamed rice cake made from year-old rice grains which are soaked, ground with water, and allowed to undergo a natural acid and gas fermentation

Production Steps1. Initial Cooking2. Grinding3. Draining of ground “slurry” (galapong)4. Preparation of starter (lebadura)5. Fermentation (1st stage) – mixing of

lebadura and galapong6. Addition of sugar and lye7. Fermentation (2nd stage)

Control of Process1. Rice – high or medium amylose content

2. Soaking time or hydration factor of rice is 3 – 4 hours

3. Fermentation temperature of 28 – 30 °C in about 42 hours; can be shortened to about 21 hours using prepared starter

4. Addition of lye reduces acidity of the product

5. Use of proper cover during steaming.

Identified Fermenting Microorganisms

•The predominant organisms were always composed of:

Leuconostoc mesenteroides (45 – 89%)

Streptococcus faecalis (20 – 50%)

Saccharomyces cerevisiae ( 18% of the population at the end of fermentation.)

Changes in Microflora

1. Starter (a) aerobic colonies of bacteria and yeast (early stages), (b) predominant LAB and yeast (later stage)

2. Drained flour – absence of aerobic colonies; presence of acid-forming

3. 1st stage of fermentation – consists of LAB and few yeast colonies

4. 2nd stage of fermentation – dominated by yeasts.

Physical Changes1. Acid development – by S. faecalis2. Leavening – by S. cerevisiae and Leuconostoc

mesenteroides3. Amylose content – main factor affecting

gloss, cohesiveness, and tenderness of cooked rice

4. High amylose content rice varieties give higher yield and greater volume than low amylose content varieties.

Biochemical Changes

1. Changes in rice during storage• Old rice is more flaky than freshly harvested

rice• Fresh rice (upon cooking), loses more solids

to the cooking water than stored• Non-reducing sugar decreased while

reducing sugars increased.• Slight drop in pH for stored rice.a

2. Changes in pH and Total Acidity•Starter: pH decreases from 6.0 to 4.2

TA (%lactate) – 0.3 to 0.62- 0.66%•Drained rice flour after 24 hours

pH 3.9 to 4.12; TA (%LA) – 0.34 – 0.42%•Fermenting Mixture

1st stage – pH: 4.4 to 4.10%; %LA 0.40 – 0.59%2nd stage – pH 7.0 decreased to pH 6.12 – 6.25;

%LA (final) = 0.24 – 0.28%

Nutritional Value• 251 calories / 100g• 3.5% protein content• 56% carbohydrates

BIBINGKA

• Method of fermentation is the same as in puto• Cooked by baking or roasting• Cooked in a moulder (bibingkahan) lined with

banana leaves• Classified as ordinary and special types.