Etiket Arşivleri: Tofu

Oriental Fermented Foods

ORIENTAL FERMENTED FOODS

MOLD MODIFIED FOODS

Reason for studying oriental fermented foods:

Different from western foods interms of taste, texture, flavor and appearance.

Different from western foods interms of microbiological standpoint: mixed culture of yeast, bacteria, and mold.

Since it is cheap and nutritious, large number of people consume.

There are too many things to modernize plants.

Oriental foods are receiving increasing attention of western consumers. hİghly nutritive because;

Complementary effect of proteins from plant and animal sources

İncreased protein efficiency ratio and digestibility

Synthesis of vitamins

Shorter cooking time

Desirable enzymes are produced

The lipoxygenase enzyme is responsible for the “beany” flavor commonly noted in soymilk. The

reaction catalyzed by the enzyme involves water, the unsaturated oil, and oxygen and the end-

product hexanal is one of the compounds responsible for the beany flavor.

Soy sauce

-dark -brown liquid with a salty taste and district pleasent aroma

– made by fermenting soybean, wheat and salt with a mixture of mold , yeast, and bacteria.

-During fermentation

Proteins …. peptidies, aminoacids, sugar alcohols, acids

carbohydrates are also hydrolysed

chemical hydrolysis is tried in U.S.A but taste of product is not the same

soy sauce is used as a seasoning agent in preparation of food

Japan leads the soy sauce industry in the world

Shoyu’ is the Japanese name for soy sauce.

In Japan the total production is about 1.04 million kiloliters (kl),

The annual consumption of shoyu per capita is about 8.3 l,

The consumption volume in Japan is decreasing slightly, but that in American and European area is increasing.

Raw Materials and their treatment

Soy Beans: defatted soybean

Soy bean ® washed ® soaked overnight ® drained ® steamed (at 10lb/ in2 for several hrs)This will

effect the future enzymatic action on soy proteins

Wheat:

Wheat ® roasted ® coarsely crushed. Adds color and flavor to resulting soy sauce and destroys

surface microorganisms and facilitates enzymatic hdrolysis

Reason of using wheat:

The mold grows better and produces more enzymes on a mixture of wheat -soybean than any of them alone

Addition of roasted crushed wheat reduce the growth of undesirable microorganism

Cooked soybean : 60 % moisture good for bacterial growth

Soybean-wheat mixture : 45 % moisture good for mold growth but not bacteria

wheat serves as a precursor of sugar, alcohols, organic acids and flavor compounds.

Wheat is rich in glutamic acid

Salt

NaCI ® gives salty taste, surpress undesirable organisms

Soy sauce koji:

Koji: is a japanese name gives to a preparation consisting of mold growth on cooked cereals or/and soybeans.

– serves as an enzyme source.(like malt in alcoholic fermentations)

Soy sauce koji is made from a mixture of roasted wheat and steamed soybeans with

A koji starter ® Aspergillus oryzae or A. soyae (Called tane koji)

Aspergillus oryzae

Aspergillus oryzae on wheat

Preparation of tane koji:

Polished rice is soaked in water overnight ® drained ® steamed for 1 hr ® mixed with 2% of wood ash, for trace elements ® inoculate with A. oryzae spores ® Spread out in tray 1,5 cm ® cover with damp clothes ® incubate at 30C for 5 days (green to yellowish spores of A. oryzae mycellium ® spores are harvested ® dried at 50 C and stored at 15 C. [ 25×107 viable spore/gm of tane koji]

A good soy sauce has 18% salt, 4.6-4.8 final pH

Price is determined by:

Nitrogen yield

Total soluble nitrogen

Amino nitrogen/total soluble nitrogen ® ratio (>50% is good)

Glutamic acid and salt are principle flavoring constituents

Sugars present are glucose, arabinose, xylose, maltose, galactose, glycerol and mannitol (also alcohols)

Organic acids: lactic, succinic and pyroglutamic

Color is due to non-enzymatic browning

SAFETY OF ORIENAL FERMENTED FOODS

Scientist can not find aflatoxin and aflatoxin producing cultures in oriental fermented foods unless they intentionally contaminate with these cultures.

Processing procedures such as cooking, salting, acid formation, antibiotics production, and low moisture are the probable reasons for the safety of oriental fermented foods.

Mycotoxins – the yellowish colonies are of Aspergillus flavus, a producer of aflatoxin.  The green colonies are of  Penicillium, another mycotoxin-producing genus (ochratoxin, patulin, penitrem, PR toxin).

TEMPEH

“Tempeh” is a fermented soybean product and meat substitute that originated in Indonesia.

It is probably the first “fast food” in that it can be deep-fried in 3–4 min or cooked in 10 min.

In the first step the soybeans are soaked in water or acidified water at room temperature.

During this stage a partial germination of the soybeans may occur depending on the amount of O2 available to the seed, and acid is produced by bacteria growing in the soak water.

Depending on the temperature during soaking, bacteria reach 108–1010 colony-forming units per ml after 24–36 h.

The pH drops from 6.5 to 4.5 due to the growth of the acid-producing bacterial species – e.g., Lactobacillus casei, Streptococcus faecium, Staphylococcus epidermidis, and Klebsiella pneumoniae that are present naturally on the soybeans.

The acid helps to prevent the growth of undesirable microorganisms, but any partial seed germination can affect the protein properties of the soybean and the subsequent fungal growth phase.

The bacteria that grow in the steeping water produce vitamin B12, a significant nutrient in tempeh.

The most desirable bacterial species for this stage is K. pneumoniae, but other pure bacterial starter cultures can perform the same function.

The soaked beans are de-hulled and carefully cooked to avoid overcooking or undercooking of the beans.

The soybeans are then drained, cooled below 35 °C, and dusted with wheat flour to provide a good source of fermentable carbohydrate, and inoculated.

The desirable fungal species for successful tempeh production, whether arising from environmental inoculation or from pure starter inoculation, are Rhizopus oligosporus

Tempeh must be consumed fairly quickly.

Defects include:

(1) black patches due to fungal sporulation,

(2) slime due to excessive bacterial growth because of too little O2 or a temperature of 42 °C,

(3) a yellow color due to growth of toxic fungi.

The yellow color indicates that the tempeh is highly toxic and it should not be eaten.

During the fungal growth phase the O2 level must be controlled at a reduced level, otherwise the fungus will grow too quickly and form black spore masses that degrade the quality of the tempeh.

The traditional way to control O2 is to wrap the inoculated beans in banana leaves, but a modern innovation is the use of microperforated polyethylene plastic.

The fungus grows and mycelia knit the beans into a firm cake to give the characteristic meaty texture.

The enzymes from the fungi transform the soybeans making them more nutritious by hydrolyzing the protein and complex carbohydrates and increasing the levels of the vitamins – riboflavin, niacin, pantothenic acid, and vitamin B6.

MISO (Bean paste)

Most popular fermented soybean good in Japan.

Fermentation principles similar to soy sauce.

Miso: like peanut butter (smooth, some chruncy) light-yellow to reddish-brown.

Bean paste (miso) is used as flavoring agent.

Freeze dried miso is getting common in western countries.

® use in dips, salad dressing, sauces

contains > 10% salt. So can be kept for a while without refrigeration

TOFU

Soy cheeses (soya cheeses) are a curd made from soymilk (soybean milk), called tofu in English.

Tofu is made in a similar process to making cheese from milk.

The soymilk is curdled by adding coagulants (CaSO4, MgCl2, glucono-delta- lacton (GDL)).

Curds are then pressed into cakes of various types.

Soft tofu is not pressed and is eaten as it is.

Medium-soft tofu is the most popular in everyday use.

Firm tofu is used in processed foods which are fried, grilled, fermented, and dried.

SUFU

Sufu is mostly sold in the west, more common under the name, Preserved Bean-curd.

sufu virtually means spoiled tofu, due to the strong flavour and pungent aroma.

Sufu resembles the dairy equivalent in cheese, Parmesan or Camembert and is sometimes referred to as Chinese cheese.

Sufu may satisfy cravings for cheese for individuals following a vegan diet.

Salting does five things:

it imparts a salty taste to the sufu,

it prevents the growth of undesirable organisms,

it stops the growth of the mold,

it releases the proteolytic enzymes bound to the mold mycelia so they can penetrate into the tofu to transform it, removes some water from the tofu blocks.

Salting can be by dry salting or brine salting.

Dry salting: takes longer, does not result in a consistent product(6–12 days),16%, washed with water.

Brining is done with a saturated salt solution, or an alcoholic brine solution in which the blocks are immersed for 4–5 days, resulting in final moisture levels of 50–65% with 12% salt.

The ethanol has two effects: first, during ripening lipolytic enzymes release free fatty acids that combine with ethanol to produce aromatic esters,

it seems to interfere with protein degradation when compared with salted sufu.

Ang-kak

Chineese originated food colorant

Washed and sterilized rice is inoculated with Monascus purpureus

In 3 days begin to redden and 3 weeks color will turn to deep purplish red

Dry at 40 C

Pigments, monoscoribrin and monoscoflavin will accumulate in the m.o. solubilise reacting it with water soluble proteins


Tofu

Tofu

It’s not so scary

What is Tofu?

Tofu is soybean curd, made by treating heated soy milk with a coagulant to produce curds. The curds are usually pressed into a block. Tofu has a soft texture and a mild flavor making it useful in many types of cuisine.

Varieties:

Silken tofu ; The traditional Japanese delicacy : the curds are left un-drained and un-pressed. This tofu has a soft, delicate texture, somewhat like custard.

Soft, regular, firm, and extra-firm tofu: The curds can also be pressed to varying degrees of firmness. The firmer the tofu, the better it holds its shape.

Flavored tofu : It may be infused with herbs and spices or sometimes baked or steamed.

( Reduced Fat Tofu is also available)

The History of Tofu

Discovered over 2000 years ago by the Chinese.

Legend claims that tofu was discovered when a Chinese cook combined seaweed nigari to a pot of soybean milk, accidentally causing it to curdle.

It was introduced to Japan in the 8th century but did not become popular until the 17th century.

Tofu was originally called “okabe.” It took on the name Tofu in the 15th century.

As interest in healthier diets increased in the west, tofu gained popularity around the 1960’s in the U.S.

Fun Facts about Tofu

Tofu can take on pretty much any flavor, making it an extremely versatile food.

Tofu can be frozen up to 5 months. Defrosted tofu has a pleasant caramel color and a chewy, spongy texture that soaks up marinade sauces and is great for the grill.

Tofu can be prepared in a huge variety of ways such as in sauces, soups, stir-fries, spring rolls, Japanese dishes, desserts, dairy-free cheesecakes and even smoothies.

Tofu never overpowers. Tofu always compliments.

Tofu is used at Buddhist banquets to imitate meat.

Nutrients in Tofu

Nutritional Value

4.0 oz of Raw Tofu

.14g Tryptophan :an amino acid and essential in human nutrition. It is one of the 20 amino acids in the genetic code.

69 mg Manganese:  important to central-nervous-system function, bone growth, reproduction,helps the body metabolize cholesterol, carbohydrates, and amino acids.

6.08 mg Iron: a component of body systems that are involved in the utilization of oxygen

9.16 g Protein : maintain the functions of the cells and organs

10.09 mcg Selenium: help prevent cellular damage from free radicals.

36 g Omega 3 fatty acids: critical for good health. However, the body cannot make them on its own

22 mg Copper : necessary for iron metabolism, for the formation of the brown pigment, melanin, in hair and skin, and in the functioning of the body’s central nervous system

110.0mg Phosphorus: an important element for many essential processes in the body

100.0mg Calcium: helps your heart, muscles, and nerves function. It is also important for bone health

34.02 mg Magnesium: needed for more than 300 biochemical reactions in the body

Health Benefits of Tofu

Cardiovascular

Soy Protein found in Tofu can lower total cholesterol levels up to 30% and lower bad cholesterol levels up to 35-40%, lower triglyceride levels, reduce blood clots and possibly raise good cholesterol levels.

Menopause

Soy may reduce menopause symptoms.

Phytoestrogens help women’s bodies maintain estrogen levels.

The calcium in Tofu may also help prevent accelerated bone loss during menopause.

How to Buy and Store Tofu

Tofu is available in several different types of packages. In natural foods stores, it is usually in the refrigerator case, often with the dairy foods. In supermarkets, it is usually found in the produce section.

Aseptic-packed tofu is shelf-stable and does not need to be refrigerated until it is opened. Once opened, it should be refrigerated and used within 3 to 4 days.

Water-packed or vacuum-packed tofu should always be kept refrigerated and used by the expiration date. After opening water-packed tofu, rinse before cooking, and change the water daily to keep stored tofu fresh.

Recipe Ideas

Thousands of Tofu Recipes can be found on the internet, try these websites to begin:

http://vegweb.com/recipes/tofu/

http://www.recipegoldmine.com/tofu/tofu.html

http://japanesefood.about.com/library/weekly/aa100801a.htm

http://www.solaeliving.com/soyproteinrecipes/

References

http://www.whfoods.com

http://www.google.com/images

http://www.soyfoods.com/soyfoodsdescriptions/tofu.html

http://en.wikipedia.org


Traditional Fermented Food Presentation

TRADITIONAL FERMENTED FOODS
Reason for studying oriental fermented foods:
Different from western foods (taste, texture, flavor and appearance.) microbiologicaly different from western foods: (mixed culture of yeast, bacteria, and mold.)
cheap and nutritious: large number of people consume.
too many things to modernize in plants.
receiving increasing attention of western consumers.
hİghly nutritive because;
Complementary effect of animal and plant proteins
İncreased protein efficiency ratio and digestibility
Synthesis of vitamins
Shorter cooking time
Desirable enzymes are produced
Soy sauce
-dark -brown liquid, salty, pleasent aroma
– made by fermenting soybean, wheat and salt with mold , yeast, and bacteria.
-During fermentation
enzymatic
Proteins® peptidies, aminoacids, sugar alcohols, acids
carbohydrates are hydrolysed
chemical hydrolysis is tried in U.S.A but taste of product is not the same
used as a seasoning agent
Japan leads soy sauce industry ( 1billion liters)
Raw Materials and their treatment
Soy Beans: defatted soybean
Soy bean ® washed ® soaked overnight ® drained ® steamed (at 10lb/ in2 for several hrs)This will effect the future enzymatic action on soy proteins

Wheat:
Wheat ® roasted ® coarsely crushed. Adds color and flavor to resulting soy sauce and destroys surface microorganisms and facilitates enzymatic hdrolysiswheat serves as a precursor of sugar, alcohols, organic acids and flavor compounds.
Wheat is rich in glutamic acid)
Salt NaCI ® gives salty taste, surpress undesirable organisms
Soy sauce koji:
Koji: mold growth on cooked cereals or/and soybeans.
– serves as an enzyme source
made from a mixture of roasted wheat and steamed soybeans with
A koji starter ® Aspergillus oryzae or A. soyae (Called tane koji)
Aspergillus oryzae on wheat
Preparation of tane koji:
Polished rice…soaked in water…drained.. Steamed…mixed with 2% of wood ash, for trace elements …add A. oryzae spores .. Spread out in tray … cover with damp clothes … incubate at 30C for 5 days (green to yellowish spores of A. oryzae mycellium… spores are harvested ® dried at 50 C and stored at 15 C.
A good soy sauce: 18% salt, 4.6-4.8 pH
Price is determined by:
Nitrogen yield , Total soluble nitrogen
Amino N /total soluble N: >50%is good)
Glutamic acid and salt: principle flavoring
Sugars: glucose, arabinose, xylose, maltose, galactose, glycerol and mannitol (also alcohols)
Organic acids: lactic, succinic and pyroglutamic
Color is due to non-enzymatic browning
TEMPEH
Indonesian and the first “fast food”.
soybeans are soaked in water or acidified water at room temp.( partial germination) acid is produced ( pH drops from 6.5 to 4.5 ) ie L casei,
The bacteria produce vitamin B12
The most desirable bacterial species for this stage is K. pneumoniae
The soaked beans are de-hulled, cooked, drained, cooled below 35 °C, and dusted with wheat flour, inoculated with Rhizopus oligosporus
Defects include:
(1) black patches due to fungal sporulation,
(2) slime due to excessive bacterial growth ( too little O2 or a temp. of 42 °C)
(3) a yellow color ( due to toxic fungi. )
The yellow color indicates that the tempeh is highly toxic and it should not be eaten.
MISO (Bean paste) in Japan.
like peanut butter (smooth, some chruncy) light-yellow to reddish-brown.
used as flavoring agent, use in dips, salad dressing, sauces
contains > 10% salt. (can be kept without refrigeration)
TOFU
Soy cheese : curd made from soymilk (tofu in English)
The soymilk is curdled by adding coagulants (CaSO4, MgCl2, glucono-delta-lacton (GDL)).
Pressed
SUFU
Sufu resembles cheese, Parmesan or Camembert and referred to as Chinese cheese.
Ang-kak
SAFETY OF ORIENAL FERMENTED FOODS
Scientist can not find aflatoxin and aflatoxin producing cultures in oriental fermented foods unless they intentionally contaminate with these cultures.
cooking, salting, acid formation, antibiotics production, and low moisture are the probable reasons for the safety of oriental fermented foods.
Mycotoxins – the yellowish colonies are of Aspergillus flavus, a producer of aflatoxin.
The green colonies are of Penicillium, another mycotoxin-producing genus (ochratoxin, patulin, penitrem, PR toxin).
SHALGAM (SALGAM)
Shalgam: (functional foods, red coloured, cloudy and sour soft drink ) traditional lactic acid fermented beverage( black carrot (Daucus carota L), bulgur flour, sourdough, salt, turnip(Brassica rapa L), and water are used for production. )
Carrot anthocyanin (eastern): traditionally grown in Turkey, Afghanistan, Egypt, Pakistan, and India
carotene (western): grown WorldwideOrange-rooted carrots that are rich in carotenes.
It is difficult to preserve carrot juice due to high pH and high risk of fermentation.
black carrot
total sugar: 5.12–6.45 g/100 g. ( sucrose (1.20–3.31 g/100 g),
glucose (1.10–5.60g/100 g), and fructose (1.00–4.36 g/100 g).
Turnip: glucose (1.41 g/100 g), fructose (1.10 g/100 g),
bulgur flour: total sugar 2.23–3.30 g/100 g and 4.44–5.84 g/100 g,
Sourdough (mixed cultures of different LAB and yeasts
LAB : L. sanfranciscensis, L. brevis, L. plantarum, L. reuteri, and L. fermentum.
yeasts : S cerevisiae, S exiguous,Candida krusei
( – no standard production technique in industry.)
two methods for shalgam production:
-the traditional method (sourdough fermentation and carrot fermentation.)
– the direct method. (only the carrot fermentation is applied. )
During fermentation:L acid, ethanol, organic compounds
Traditional Production Method
Traditional Production Method

1- First Fermentation (Sourdough fermentation): enrichment of LAB and yeasts. -Bulgur flour (3%), salt (0.2%), sourdough (0.2%), and adequate water are mixed.
-room temperature for 3–5 days. -.(pH drops .)
2-Second Fermentation (Carrot or main fermentation)
extracts from First fermentation are combined with sorted and chopped black carrots (10–20%), salt (1–2%), if available sliced turnip (1–2%) . wooden vessels, fiber glass, plastic, or stainless steel tanks.
Fermentation : 3 to 10 days at 10–35°C., colour compounds (anthocyanins) are extracted.
can also be seasoned by adding chilli powder.) no Clarification is applied. marketed in sealed bottles and plastic containers
Direct Production Method
Factors Affecting Shalgam Fermentation
– microflora ( LAB, yeast, no commercial cultures available, inoculating up to 15% of shalgam from a previous production )
– chemical composition of raw materials ( turnip improves sensory characteristics, Bulgur flour: nutrent source for microorganisms)
– fermentation temperature(at 20–30°C Leuconostoc mesenteroides and yeasts are favoured, LAB grow rapidly at 30–35°C. extraction of anthocyanins)
– salt. 1–2% to control the flora, favouring LAB Leuconostoc spp. Are the least tolerant to salt,
Lactobacillus spp. and Pediococcus spp. have similar salt tolerance
The composition of shalgam beverage
BOZA
Boza is a colloid suspension light to dark beige, sweet, slightly sharp to slightly sour beverage consumed daily in Bulgaria, Albania, Turkey, and Romania.
It is made from wheat, rye, millet, maize and other cereals mixed with sugar good source of bacteriocin-producing lactic acid bacteria
LAB: L plantarum, L. acidophilus, L. fermentum, Leuconostoc raffinolactis, Ln. mesenteroides and Ln. brevis.
The yeasts: S cerevisiae, Candida tropicalis, C. glabrata, Geotrichum penicillatum and G. candidum
BOZA PRODUCTION
-the grains: washed, cooked in an autoclave for 2 h at 4–5 atm.
mixed with cold water at a ratio of 1:1 volume parts.
-fermented 2-3 days at room temp ( old boza and yeast innoculated)
-The mash is percolated and then stored at 4C.
-Sugar is added before bottling
Boza was prepared in the traditional way.
Maize, wheat and rice flours were mixed in the
ratio of 2:1: 1. respectively.
boiled in 3 times water (w/v) for 1 h under continuous stirring. Cool overnight and diluted by 2.5 times with water and sugar (20% w/v) was added.
Inoculum (2%) ( backslopping) Fermented at 25-30 C
Boza without preservatives nor unpasturised has two days of shelf lives. Then it gets too sour.
Storage at 4 C could maintain the good qualities of the drink up to10 days.
Ed. Ahmet Nezihi Turan;
Ministry of Culture and Tourism Publication , Ankara 2007,