Fermentation

FERMENTATION

FERMENTATION  The

oldest form of food preservation.  Encourage multiplication of m/o.  Definition – Chemical conversion of carbohydrates into alcohol or acids

Sugar

yeast

Alcohol/acid/CO2

Cont.   

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Zymology – science of fermentation Ethanol fermentation product – wine, beer, bread Lactic acid fermentation product – sour food (yogurt,kimchi)– also by mamalian muscle

Microbes – – –

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Alter the texture of foods Preserve foods (product of alcohol/ acid) Produce subtle flavours and aromas

Supplemented with other operation – – –

Pasteurization Chilling MAP

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Lactobacillus lactis – dairy Steptococcus thermophilus –dairy Leuconostoc sp. – wine, dairy Pediococcus sp. – meat, vegetable, ripening of some cheeses Lactobacillus sp. – meat, vegetable, dairy, sourdough Bifidobacterium sp. – dairy – promote intestinal health Propiopnibacterium sp. – Swiss cheese Yeast – bread, beer, wine, liquors Molds – ripening cheeses, soy sauce Lactobacillus delbruekii,subspecies bulgaricus & Streptococcus thermophilus – yogurt

Benefits ! 

Preservation – inhibitory to the common pathogenic m/o (Clostridium botuinum)-can’t grow at pH<4.6.

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More nutritious – not only catabolic, but also anabolic  synthesize complex of vitamin (riboflavin, B12,C) protein mycilea

enzyme

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– mold  rich in cellulose-splitting

Disease prevention – Paracoccus denitrificans (carrot

Factors Controlling Fermentation 

Acid – –

Have inhibitory effect Naturally formed/added to prevent further spoilage – In acid cond, preservative power increased. If O2 available – oxidation occurred – natural cond. – Eq: milk – naturally fermented cheese 

Alcohol – Preservative effect – Depends on concentration (12-15% by volume) – Sometimes need pasteurization (increase

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Starter – – – –

Selected strains of lactic acid organism Quick & dependable acid production Specified culture are available Before put the starter, heated-- inactivate other competitors – Ancients times – naturally created 

Temperature – Depends on the ability of m/o. temp, acid content. – <37°C, more bacteria produce acid-- kill other m/o.

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O2

– Aerobic condition encourage development of mold – Mold oxidize acetic acid to CO2 & water

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Salt

– Added to control/inhibit proteolytic organism & spoilage types. – Frequently added as water drawn from vege will dilute brine solution.  Sauerkraut – 2.0-2.5% added into cabbage  Pickled olive – 7-10% added into olive  Pickled cucumber – 15-18% added

 Eskimos

– Prepared fermented fish by digging a hole about 2 ft in the ground. – Put the freshly caught fish in the hole – Covers with earth & let it buried for a couple of weeks/> 1 month. – After reaching the desired level of fermentation – unearth – freeze immediately eat – Tastes best raw and frozen

 African

– Fermented fish popular in Ghana, Uganda, Burundi. – However unclean practices may cause dangerous consequences. – Factors  Water  Cleaning practices  Gutting  Environment

Fish Sauce  Salty,

smelly brown liquid made from fish that is the single, most important flavoring ingredient in Thai cooking (Laos, Cambodia, Vietnam, Burma & Philipines).  Called “nam bplah” in Thai, genuine fish sauce is the water, or juice, in the fish that is extracted in the process of prolonged salting & fermentation.

Processing Small fish Rinsed & drained Mixed with sea salt Filled into large earthenware jars On the bottom with a layer of salt topped with a layer of salt Covered & left in a sunny location for 9 months-year * Protein content increase (9.6 to 15.2%)-from

SOY SAUCE MANUFACTURING

INTRODUCTION SOY SAUCE (shoyu) THIN SAUCE 

Salt > 14% (salty)

Fermentation 40 days – 6 months  

cheaper

THICK SAUCE Salt ( 10 – 13%)  Contains more sugar, caramel, conditioner, flavouring 

Fermentation 6 months – 24 months.  

Expensive than thin sauce.

Under the same legislation : Regulation 340 & Regulation 28 (Food Act 1983 & Food Regulation 1985)

INGREDIENTS    

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Defatted soy bean/mature soy bean Wheat flour Innoculum (culture of Aspergillus oryzae) Brine solution (conc.:depends on types of soy sauce) Sugar Caramel Food preservatives (eg: benzoic acid) Flavour enhancer (eg:

MANUFACTURING METHOD SOY SAUCE

Chemical Method - Mineral acid – hydrolyse the protein & carbohydrate

Chemical and microbiological Method - Acid hydrolysed and fermentation to produced shinshiki

Microbiological Method - 2 step fermentation

PROCESSING OF SOY SAUCE 

Traditional method

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Modern method  produce high Q of soy sauce  fulfill the requirement in Food

Regulation 1985.

MODERN METHOD

washing Soy bean

Put In Fiber Tank

Soaking (10 hrs) *remove seed coats/hulls Koji (greenish yellow) + brine(22%)

Boiling (20min,15psi) *horizontal retort Incubate in Koji Room (30°C,RH 90%, 48 hrs)

Cooling

Put onto rack

Mixing (Wheat Flour,20% Innoculum,0.1%) *Aspergillus spp. Put In Tray-2cm thick (stainless steel)

[1:3-koji wt :brine wt]

Moromi *sampling for Kjeldahl method-not less than 0.9%N2

Fermentation 2-18 months

Extraction & Filtration

Raw Soy Sauce

Aging Tank (1 week – sunlight)

Bottling

Sedimentation Tank Pasteurization (80°C,30min)

Filter

Mixing Tank

PROCESSING PLANT

CRITICAL CONTROL POINT STEP

HAZARD

1. Ingredient of koji; soy bean, wheat flour.

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moisture Insect Microorganisms

2. Boiling of soy bean

Uncooked

3. Innoculum

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4. Koji

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soy bean: effect growth of mould & N2

production low Q of innoculum – effect fermentation of koji.

uncontrolled temp:- high temp - inhibit the growth of A. oryzae - low temp. – growth of Rhizopus nigrificans (black mould) *Best temp. in fermentation of koji 30°C - 35°C.  uncontrolled moisture - high moisture – growth of bacteria * Best moisture content of soy bean 43% - initial of incubation

CRITICAL CONTROL POINT….cont. STEP 5. Concentration of brine

HAZARD  less 20% - enhance the growth of undesired microorganism

6. Pasteurization

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7. Cleaning and sanitizations

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incomplete – effect the flavour and the shelf life of soy sauce. unsanitized of the factory will effect the whole of soy sauce production.

CURRENT ISSUE 

3.

4.

Before the Gazette of Food Regulation 1985, a lot of soy sauce manufacturers:  

Used saccharin as sweetener in soy sauce. Used recycled alcoholic bottles.

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Addition of Acid Hydrolysed Vegetable protein to accelerate production of soy sauce.

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Problem in meeting the requirements of the total nitrogen of soy sauce – because of the poor processing

The main source of 3-MCPD (3-monochloropropane-1,2diol) in soy sauces is from the addition of acid-hydrolysed vegetable protein (acid-HVP), a savoury food ingredient which has been found to contain 3-MCPD. 3-MCDP is a group of chemicals known as chloropropanols.

MAKING OF KOJI  After boiling, the soy bean will be cooled and mixed with wheat flour and spreaded on the bamboo tray – incubate for 3 – 4 days for allowing the growth of selected mould (Aspergillus spp.) KOJI formed

 No deliberate innoculation repeated  Use of same trays (ensure that same organism are carried from one fermentation batch to another)

FERMENTATION  Koji and brine (16 – 18%) are put in earthen jar under sunlight (10 – 12 weeks).  Cover during the night & rainy day  Moromi formed

SORTING  Good Q of soy bean is important in making soy sauce.  During sorting – defected soy beans are separated.

BOILING  Soy beans are boiled in a boiler (horizontal retort (20 min, 15 psi).  Boiling – breakdown the protein structure of the soy beans – *will be hydrolyzed by the protease (Aspergillus oryzae).

MIXING 

Cooled soy beans + wheat flour (20%) + innoculum of Aspergillus oryzae (0.1%) in mixer, eg: ribbon mixer.

Aspergillus oryzae

STAGE 1 :KOJI 

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The mixture is spread (2cm thick) onto the stainless steel tray (with hole). These trays are covered with muslin cloth. Incubate in koji room– 30°C/48 hrs/RH 90% At this stage – protein, oligo and polysaccharides are hydrolyzed – Aspergillus enzyme This results in production of fermentable sugar, peptides and amino acids. Mould grow Koji formed (greenish yellow - good Q). Longer incubation – allow the growth of undesirable black moulds.

FERMENTATION 

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Koji - put into food grade fiber tank – equipped with cover, valve, pipe, filter, air flow. Brine (22%) is put into this tank. 1:3 (koji’s wt : brine’s wt) – to kill the growth of Aspergillus oryzae.  moromi formed Lactic fermentation occurs – Lactobacillus delbruckii & Pediacoccus soyae

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Followed by alcoholic fermentation (by yeast) – Zygosaccharomyces rouxii

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Exposed to the sunlight – Bright and sunny weather tends to be more conducive in producing soy sauce of better Q and aroma. Exposure for 2 months – to get the min aroma of soy sauce and continuously developed.

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To ensure the conc. of the brine not less than 20% - use brinometer.

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Fermentation of moromi within 45 days (min period to dissolve 56%- 68% of total nitrogen from soy bean).

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Total nitrogen in raw soy sauce (45 days) 0.9 – 1.1% - depends on the type of fermentation tank ; fiber/earthen jar/stainless steel.

Brinometer

Moromi

EXTRACTION & FILTRATION  After

fermentation, raw soy sauce will be extracted and filtrated to aging tank – using hydraulic/pump.  In aging tank – the mixture sunned for a week– to develop aroma and flavour.

SEDIMENTATIONS  The

raw soy sauce will be pumped to the sedimentation tank.  Sampling for the total nitrogen using Kjeldahl method – the total nitrogen supposed to at least 0.9% before mixing with other ingredients and pasteurization – may lost during heating.  The processed soy sauce must contains at least 0.6% total nitrogen

MIXING 

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Raw soy sauce with sufficient nitrogen will be pumped to the mixing tank. Brine (18%), sugar, caramel and food additive will be added in the ratio 1:2 (vol ingredient : vol raw soy sauce). Caramel and sugar  to condense and sweeten the sauce. Caramel  calouring agent Food preservative ; eg : benzoic acid – not more than 1000 ppm (Food Regulation 1985). Flavour enhancer also can

PASTEURIZATION 

Raw soy sauce will be pasteurized at 80°C/30 min in mixing tank equipped with  stirrer and jacketed thermal oil (to prevent – burnt and crusty), or  Plate heat exchanger.

BOTTLING 

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The processed soy sauce will be filled into sterilized bottles using high pressure vacuum. Soy sauce – capped, labelled and distributed.

Conclusion  All

of the food potential to be fermented (naturally/ modified), but if there’s no controlled handling, proteolitic and lipolytic will replace the process and spoiled the food.

TODAY’S THORN IS TOMORROW’S FLOWER

CHARACTERISTICS OF FIBRE TANK  Food

grade  recyclable and allows for easy disposal  high-temperature performance  corrosion resistance