Proteases

It has been shown that the proteases of Aspergillus oryzae or Aspergillus sojae include seven kinds of proteases with four different optimum pH values. Of these proteases, alkaline protease has been studied in most detail (47). It is a serine enzyme and is active in a broad pH range (between 6 and 11). Neutral proteases are zinc proteases. Neutral proteases have specificities that are common to the metal proteases of microorganisms. The proteases described above are all endotypes that hydrolyze...

Gel Formation During Fermentation

During the manufacture of semisolid dairy foods, an irreversible gel is formed due to the destabilization of the casein micelle. The gel can be classified into one of the following groups based on whether it is (a) enzymatic, (b) acid-induced, or (c) salt heat-induced (14). The gel or coagulum formation in fermented semisolid dairy foods is primarily of the acid type similar to that of acid-set cheeses. In acid-set cheeses, however, syneresis is desirable, whereas in yogurt or other semisolid...

Increased Shelf Life of Kimchi by Fermentable Sugar Reduction

Kim et al. (63) studied the sugar content of radishes to improve the storage stability of cubed radishes by monitoring the titratable acidity (TA) at the completion of fermentation. The final TA obtained at the end of fermentation was directly proportional to the sugar content of the radishes, with a value of 0.29x + 0.4428, where x is the sugar content of the radish. These investigators also studied the relation between the soluble solids (SS) content of baechu cabbage and the final TA value...

Introduction

In Europe, starter cultures of molds are primarily used for the production of cheese and meat, and worldwide the production of a variety of indigenous foods is based on spontaneous mold fermentations (Table 10). Molds grow only in the presence of oxygen, which limits their applications. In general, molds are known as effective producers of enzymes, and their proteolytic and lipolytic activities are often high several molds also have extracellular glycoamylase activity. Furthermore, molds are...

Yeasts

Although yeasts play a minor role in dairy fermentations, several fermented milk products with a natural yeast-containing microflora exist. A distinctive feature of these products is that, in addition to the lactic acid fermentation induced by lactic acid bacteria, a slight alcoholic fermentation due to yeasts takes place (41,42). The best-known examples offermentation of milk by a combination of yeasts and lactic acid bacteria are kefir and kumiss, both originating from countries of Eastern...

Streptococcus thermophilus

This organism is a gram-positive, catalase-negative anaerobic coccus and it is largely used in the manufacture of hard cheese varieties, mozzarella, and yogurt. It does not grow at 10 C but grows well at 45 C. Most strains can survive 60 C for 30 min (22). It is very sensitive to antibiotics. Penicillin (0.005 IU mL) can interfere with milk acidification (20). It grows well in milk and ferments lactose and sucrose. Two percent sodium chloride may prevent growth of many strains. These...

Fermented Jalapeno Pepper

This preservation method is based on acid production by fermenting sugars in the plant material through the action of lactic acid bacteria such as Lactobacillum plantarum, although the presence of Leuconostoc mesenteroides also has a marked effect upon the fermentation and product quality (5,6). In addition of lactic acid bacteria activity, other fermentative bacteria, such as acetic acid-producing microorganisms, also carry out vegetable fermentation, which enhances shelf life and sensory...

Info

H-keto acid decarboxylation or fatty acid h-oxidation Interaction of free carboxylic acids and alcohols Maillard reaction of amino acids with carbohydrates Sulfur-containing amino acids with carbohydrates Some of these tasty peptides, mainly di- and tripeptides, have been successfully purified and sequenced (37). Free amino acids may also serve as a source of volatile compounds during further ripening (75) or when the ham is heated, like the country-style ham (76). Aroma development in...

Oxygen Absorbers

The most widely researched and patented area of active packaging is the use of oxygen-absorbing systems (80-83). Since the first iron-based pouch-type oxygen absorber was introduced to the market in Japan in 1977, there has been a sharp increase in designs and applications of oxygen absorbers, first in Japan and then also in the United States and last in Europe (82). The most widespread type is based on powdered ion others are based on ascorbic acid, glucose oxidase, alcohol oxidase, and...

Manufacture of Pouchung and Dungding Oolong

Wenshen Pouchung tea and Dungding Oolong tea are typical examples of Pouchung-type tea. They have lighter degree of fermentation among all the partially fermented teas. These teas have only 8-18 of their polyphenols oxidized and have a dark green appearance. Color of brewed liquor ranges from honey green to honey yellow, or golden yellow. These teas are bright and transparent, and their taste is lively, sweet, and smooth. Aroma is fresh pure, and flowery (fragrant). Wenshen Pouchung tea is...

Aluminum Laminated Pouches

Aluminum laminated pouches have a beautiful outer appearance and the advantage of exceptional impermeability to moisture, light, and air. However, they are more expensive than PE bags. Because of compression problems if used alone, these packages are often equipped with a cardboard box or composite-paper box as an exterior package. Aluminum laminated pouches can be used with vacuum packaging, nitrogen-flush packaging, or oxygen absorbents or scavengers, and solve the oxygen problem in the bag....

Temperature

The temperature of the sourdough is influenced by the temperature of the flour, the water, and the mother sponge, and it is often adjusted regulated by the water temperature. In practice, the temperature increases 6 to 8 C during fermentation on an industrial scale if the temperature is not thermostatically regulated, so it is important that the temperature of the water is not too high. The temperature of the sourdough greatly influences the microbial propagation and production of acids, as the...

1

Mature at 5 C for 24 hr iJattcT The packages are put into shallow sliced-wood or polystyrene trays and set in a warm thermostatic chamber with a controlled temperature at 40 C. After 14-20 hr of fermentation, the bacteria will have covered the beans with a white sticky coating, indicating the time for harvesting. Overfermentation should be avoided because it leads to release of ammonia, which not only spoils the natto flavor but also destroys the B. natto and promotes spoilage by other...

Polyethylene PE or Plastic Bags

PE bag is a fairly commonly used package for tea leaf in Taiwan. In general, there are two kinds, the low-density and high-density PE. Low-density PE bags are more permeable to moisture and air than the high-density PE. The advantages of PE is that it is economical, with reasonable resistance to moisture, and its disadvantages are transparency and permeability to air. So it is not suitable to be used alone for packaging tea leaf. Currently, many tea leaf wholesalers still use PE bags for direct...

Tempeh

Tempeh, or tempe in some literature, is another fermented soy food. Widely believed to have originated in Indonesia centuries ago, tempeh is made by fermenting dehulled and briefly cooked soybeans with mold, Rhizopus. Freshly prepared tempeh is a cakelike product, covered and penetrated completely by white mycelium, and has a clean, yeasty odor. When sliced and deep-fried, it has a nutty flavor, pleasant aroma, and crunchy texture. Unlike most other fermented soy foods, which are usually used...

Current Developments

Lactic acid and acetic acid are the major products of sauerkraut fermentation, and their concentrations in the finished product are highly variable. Research is needed for improvement in the uniformity of sauerkraut quality. Possible methods for controlling the level of acidity in the finished product include (a) pasteurization of the product when it reaches the desired acidity, (b) development of cabbage varieties with a low concentration of fermentable sugars, (c) dilution of the product with...

Process Mechanization In The Manufacture Of Fermented Foods

Fermented foods produced by traditional methods are labor intensive and rely a great deal on the experience of the manufacturers. The main drawback is product inconsistency. Many cheeses, yogurts, breads, sausages, and soy sauce are now made by highly mechanized processes to standardize the products in most developed countries (57-65). This not only provides product consistency but also reduces production costs. Consumers benefit from these developments. However, some consumers, even in...

Storage Treatment And Preparation Of Cheese

All cheeses except those consumed fresh must undergo a storage period for some amount of time. This is necessary in order for the enzymatic processes that determine the maturation of the cheese to have an appropriate reaction time. This reaction time varies significantly between different types of cheese, depending on which reaction takes place. For similar cheese types, it is common to use different storage times, depending on the taste desired and the temperature used. The possibilities for...

Types of Sourdoughs

Sourdoughs can be started as follows By adding a piece of mature sourdough (mother sponge) Most sourdoughs used in both wheat and rye bread baking are still initiated by adding a piece of mature or ripe sourdough, also called mother sponge, but there is a tendency to use defined starter cultures with specific fermentation patterns or production of antimicrobial substances. This tendency increases as these cultures become commercially available. When dough made from flour and water is left for 1...

Subingredients and Natural Preservative Plants

Kimchi subingredients were examined for their ability to inhibit the growth of microorganisms. An increased garlic concentration (0-6 ) in the preparation decreased the number of aerobic bacteria but increased LAB levels at 2 days (early stage fermentation) at 21 C (44). A recipe of 2 percent garlic content in kimchi decreased the amount of aerobic bacteria significantly (50- to 1000-fold) compared to a kimchi recipe of 1 garlic. Cho and Jhon (45) also reported that 21...

Iitypes Of Fermented Soy Foods

There are four major fermented soy foods (soy paste, soy sauce, tempeh, and natto) and three minor fermented soy foods (sufu, soy nuggets, and soy yogurts). Table 1 lists English names, local names, and general description and uses of fermented soy foods. Fermented soy foods vary greatly in terms of microorganisms involved, methods of preparation, length of fermentation, principles, and end uses. It takes only a few days to prepare tempeh and natto, but preparation of the remaining types of...

Utilization of Oxygen Free Packaging

Oxygen is present everywhere, with about 20 in concentration in air. Presence of air is definitely related to deterioration of tea quality during storage, giving rise to '' aged,'' rancid, and reversed taste, discoloration, and weakening of the lively taste. Solution to the problem of oxygen in packaged containers is urgently needed. There are many methods to prevent the tealeaf from reoxidization during storage, such as vacuum packaging or nitrogen-flush packaging. These two techniques are...

References

Botanical classification of tea. In K. C. Willson and M. N. Clifford. ed. Tea Cultivation to consumption. London Chapman & Hall, 1992, pp. 25-51. 2. Anhui Agricultural College. Chapter 1 Classification of tea. In Tea Manufacturing. Peking Agriculture Press, 1992, pp. 13-23. 3. CK Cheng, GK Yao, SX Zhuang, Y Bai. Chapter 4 Famous Chinese Tea. In Science of Drinking Tea. Taipei Vacation Press, 1992 pp. 64-83. 4. Anhui Agricultural College. Chapter 10 White tea. In Tea...

Longer Shelf Life

During storage of bread, several different physical and microbiological changes occur, lowering the quality of bread. The bread crumb becomes hard, the bread crust changes from crispy to leathery, and the characteristic and favorable bread flavor disappears. All these changes are characterized as the staling process. Within few days the bread might be spoiled due to contamination and growth of molds on the surface or development of rope in the bread crumb caused by Bacillus spp. Addition of...

Sanitation Management And Quality Controls

Fermented soy foods are traditional, fermented foods with characteristic flavor produced by utilizing the enzymatic reactions of microorganisms and suitable processing methods. In the manufacturing processes, sanitary management is critical. Besides those criteria that should be followed as discussed in the chapter on soy sauce, suitable microorganisms have to be selected for the various kinds of fermented soy products for proper fermentation. During the course of manufacture, it is critical to...

Manufacture of Fenghuang Shuixian

Plucking of Fresh Leaves There are many good cultivars in the Fenghuang (Pheonix) mountain in Guangdong Province. The tea farmers there selected single clones suitable for manufacturing of good quality tea. They grow this single clone and pluck only this same clone for Fenghuang Shuixian tea manufacture. Shuixian is a more popular cultivar. In general, plucking is conducted four times a year, (spring summer, fall and winter). Tea made from spring plucking is more common and has the best...

Microbiology Of Fermentation

In kenkey production, fermentation occurs during the steeping of maize and the fermentation of the dough. Earlier studies on the microbiology of maize dough fermentation during kenkey production carried out in 1970, reported the presence of a mixed population of lactic acid bacteria and yeasts at the advanced stage of fermentation (11). The bacteria consisted of homofermentative Pediococcus cerevisiae and the heterofermentative species Leuconostoc mesenteroides and Lactobacillus fermentum....

Inoculation with Natto Bacteria

The cooked beans are taken out from the cooker. The natto starter is inoculated immediately and mixed thoroughly. The amount of inoculum is 1 kg of raw beans to 1 ml liquid inoculum or 1 g inoculum powder. When liquid inoculum is used, the starter is diluted with 100 ml of sterilized water before inoculation. Commercial natto starter contains bacteria in the spore form. One ml or 1 g of this starter has 108 spores or more. When it is used to inoculate small soybeans (6500 beans per kg), each...

Origin of Leaf Mustard Pickles

The origin of leaf mustard fermentation is hard to trace. It is generally believed that the origin is in the Orient. When Emperor Chin Shih Huang was constructing the Great Wall of Figure 1 Mature head-type mustards pior to harvest for leaf mustard pickle fermentation. Figure 1 Mature head-type mustards pior to harvest for leaf mustard pickle fermentation. China in the third century b.c., a portion of the coolies' rations consisted of a fermented mixture of vegetables, probably mustards,...

Reduced Phytate Content by Sourdough

Whole-meal cereals are good sources of minerals such as K, P, Mg, Fe, and Zn but without treatment, the bioavailability is poor for minerals stored as phytate, an insoluble complex with phytic acid (myoinositol hexa-phosphoric acid, IP6). The content of phytate is 6 mg g rye grain (115), 3-4 mg g in flour of soft wheat and 9 mg g in hard wheat flour (116). Phytate accounts for more than 70 of the total phosphorus in cereals, and it can be degraded during the bread-making process due to the...

Sourdough

Rye bread, several wheat bread types, and some sweet baked goods have traditionally been fermented with sourdough. Besides improving the flavor and texture of the bread, this mixture of lactic acid bacteria and yeast increases the shelf lives of these products (38). The antimicrobial effect oflactic acid bacteria has been assigned to both the lactic and acetic acids produced during fermentation (39,40) newer studies, however, have shown that lactic acid does not have an antimicrobial effect...

Alcohol Formation

Lactic acid bacteria metabolize pyruvate anaerobically, yielding varying amounts of carbon dioxide, acetoin, diacetyl, 2,3-butanediol, acetic acid, ethanol, and lactic acid (81). Volatile acyloins (alpha-hydroxy ketones) are obtained by condensing either aldehydes with pyruvate or 2-keto acids with acetaldehyde in a reaction catalyzed by yeast pyruvate decarboxylases (EC 4.1.1.1). Odor qualities and threshold values of 34 acyloins were evaluated, and 23 of them possessed distinct flavor...

The History Of Kimchi

Records indicate that salted vegetables as a type of macerated vegetable were consumed in Korea as early as the 3rd or 4th century a.d. (6). The first record of kimchi appears in the Koguryojon of China's Weizdongyizhuan region, Samguozhi (a.d. 289). The book states, ''The Koguryo people referring to the Korean people are skilled in making fermented foods such as wine, soybean paste, and salted and fermented fish.'' This passage indicates that fermented foods were widely enjoyed at that time....

Chemical Modification of Amino Acids

Too much heat treatment decreases the extent of proteolysis by causing other changes in the proteins. a- and s-amino groups may be modified by the Maillard reaction. The modification of the lysine and arginine residues on the protein molecules may reduce the digestability of koji protease. Some of the koji protease attacks the side chain of basic amino acid residues, such as lysine and arginine. Glutamine is chemically changed to pyroglutamic acid, which has no taste (24). During severe heat...

Standard Yogurt Processing

An overall scheme of yogurt processing is included in Fig. 5. Milk or standardized yogurt mixes are heat-treated to high temperatures well above minimum legal pasteurization. LTLT pasteurization at 85 C for 30 min or 88 C for 15 min or HTST pasteurization at 88-91 C for 30 sec to 5 min are typically employed. The purpose is twofold. First, high temperatures destroy indigenous bacteria, particularly themodurics, which reduces competition and enables rapid growth of the culture bacteria. Second,...

Fermented Tofu

Sufu or fermented soy cheese is made from fermenting tofu that is made by coagulating the soy protein in soy milk with calcium and or magnesium sulfate. It is similar to feta cheese in its fermentation process. Both products are matured in brine in sealed containers. Some packed sufu contains flavoring ingredients. Table 47 lists the basic steps in the manufacture of sufu. For detailed information, readers should refer to the list of references in this chapter and Chapter 31 on fermented tofu...

Vitamins

Kimchi is known to be a good source of vitamins in the Korean diet. The raw ingredients used for kimchi preparation contain high levels of vitamins, but some vitamins can be synthesized during the fermentation. Table 9 shows vitamin contents of common kimchi, the average contents of vitamins in three different starter-inoculated kimchis, and the common kimchi during fermentation at 3 to 7 C (77). The levels of vitamin B1, B2, B12, and niacin are all increased during the course of fermentation....

Dough Properties and Bread Texture

Incorporation of sourdoughs in wheat bread making influences the gluten proteins and the viscoelastic behaviour of doughs due to the drop in pH value caused by the organic acids produced. Several investigations have shown that the addition of acid to wheat dough decreased the dough stability during mixing, and the acidified doughs became considerably softer than a nonacidified control dough (82-84). Dough stability was also decreased when it was prepared with the addition of sourdough (85,86)....

Modified Atmosphere Packaging

In modified atmosphere packaging (MAP), the air inside the package is replaced with a single gas or a mixture of gases. The choice of gas atmosphere depends on the product to be packed, and for bread it usually consists of pure nitrogen (N2), pure carbon dioxide (CO2), or a combination of these. Other gases are only seldom used. N2 is an inert, tasteless gas with low solubility in water and lipids. It has no antimicrobial effect but may be used to displace oxygen from the packaging atmosphere,...

Microbiology Of Sourdough

The microflora of the sourdoughs includes adapted LAB and yeasts that have optimal conditions for growth and fermentation similar to the conditions for the sourdough (temperature, water content, pH), and which probably produce antimicrobial compounds (41). The microflora in bakery sourdoughs remains remarkably stable despite the use of nonaseptic fermentation conditions (20,23,34,42). The LAB and yeasts isolated and identified from rye and wheat sourdoughs are listed in Tables 3 and 4,...

Production of Sourdough

Sourdough can be made with variations in the following parameters flour type wheat rye, flour extraction rate, flour water ratio, temperature, time and amount of starter. Sourdough can also be made in one to three steps. The one-stage process is the basic way to make a sourdough and is widely used. Two- and three-step sourdoughs have traditionally been used in rye bread production in many German bakeries (21). Industrialization in bakeries has also included sourdough production, where the...

Natto

Originating in the northern part of Japan about 1000 years ago, natto is one of the few products in which bacteria predominate during fermentation. When properly prepared, natto has a slimy appearance, a sweet taste, and a characteristic aroma. In Japan, it is often eaten with soy sauce or mustard, and served for breakfast and dinner along with rice. Similar products are found also in Indonesian and Thailand but not in China. To make natto, soybeans, preferably small-seeded, are washed and...

Bifidobacteria

This Y-shaped organism was isolated from infant stool in 1899 at the Pasteur Institute by Tissier (21). There are 24 species in this group. Nine of these are of human origin and the other 15 come from animals (40). These gram-positive organisms are strictly anaerobic. The degree of tolerance to oxygen depends on the species and the growth medium. It appears that the strains of B. bifidus are relatively aerotolerant (40). Optimum growth temperature for species of human origin is 36 -38 C no...

Upgrading Of Traditional Technology And Use Of Starter Cultures

Several studies have been carried out to upgrade and mechanize some of the unit operations involved in the production of kenkey, including the development of shelf-stable dehydrated fermented maize meal flour as a convenience intermediary product. As mentioned above, a partly updated traditional production site is shown in Fig. 3. Spontaneously fermented maize dough has been successfully dehydrated in a hot air tray dryer (Fig. 4) at temperatures of 60 C, 120 C, and 200 C to produce acceptable...

Sufu

When fresh tofu is fermented with a strain of certain fungi such as Mucor hiemalis or Actinomucor elegans, it becomes a new product known as sufu or Chinese cheese. The product consists of tofu cubes covered with white or yellowish-white fungous mycelia, it was firm texture, salty taste, and characteristic flavor. Although relatively unknown in some adjunctive countries such as Japan and Korea, sufu was produced in China long before the Ching Dynasty and is consumed mainly as an appetizer or...

Fermentation and Its Management

The optimum germination temperature for B. natto spores is about 40 C. The spores can still germinate after storage at 0 C for one year. In actual practice, the cooked soybeans are inoculated at about 80 C. Fortunately, the B. natto spores are heat-tolerant and can survive this exposure to high temperature. This heat-shock helps induce the dominant spores to germinate. After exposure to 100 C for 3 mins, or 80 C for 30 mins, the spores start to germinate. It is important that the beans be...

Enzymes in Natto Beans

Natto beans have a microbial population of 108 g. The natto bacteria produce different enzymes. Among them, proteases are the majority. Alkaline protease reaches an amount that can be crystallized. At pH 8.2 and at 55 C, it has the highest activity. It is also stable between pH 5 and 9. It is not stable at temperature above 55 C. Heating at 65 C for 30 min can inactivate this enzyme. The activity of this enzyme is stronger than the hydrolytic powder of commercial pancreatin on casein. Other...

Mixing of Brine and Soya Koji Mixture Mashing or Fillinthe Crock

Brine cooled to 0-5 C in the summer can avoid sedimentation and darkening of soy sauce. The mixing container, such as a cement or fiberglass tank, is filled up with brine (Fig. 5). Disintegrated and cooled soya koji mixture is then added. Compressed air is used to stir the mixture. The amount of mashing water (brine) is in the '' 10 water'' to '' 11 water'' range. Nowadays, when defatted soybeans are used, it is common to use '' 12 water'' to '' 13 water.'' Use of lesser amounts of brine will...

Therapeutic Properties Of Liquid Fermented Milk Products

Medicinal value of liquid fermented milk products has been suggested for hundreds of years, and various studies have implied that individuals for whom fermented milks such as acidophilus milk, Bulgarian buttermilk, and kefir is a part of the diet as in some parts of Russia, live long lives (1). This value goes beyond the accepted high nutritional quality of unfermented milk. The fermentation process apparently adds therapeutic qualities to milk that are not found in the original milk. These...

Formulation of Raw Materials

In general, equal amounts of defatted soybeans and wheat are used in the manufacturing of soy koji. The volume of brine at Baume 19-20 (22.5-23.7 sodium chloride, average 23.1 ) is 1.2 times the total volume of soybeans and wheat i.e., approximately the sum of weight of soybean (divided by specific gravity 0.6) and weight of wheat (divided by specific gravity 0.75). This is called '' 12 water.'' Brine added at 1.1,1.3, and 1.4 times are called '' 11 water,'' '' 13 water,'' and '' 14 water,''...

Nonstarter Lactic Acid Bacteria NSLABLactobacillus paracasei

There are almost always bacteria that are not added as a culture during cheese production that grow to high numbers in the cheese during ripening. Facultative heterofermentative Lactobacillus (FHL) and most commonly Lb. paracasei are found dominating in high-quality Scandinavian semihard cheeses, and their importance increases with ripening time (12-14). They are present at low numbers at the beginning of ripening, and no significant influence on the primary production of medium-sized peptides...

Foam Cleaning

Foam is beneficial for cleaning large surface areas and can be used to clean transportation equipment exteriors, ceilings, walls, piping, belts, and storage containers. Portable foam equipment is similar in size and cost to portable high-pressure units. This cleaning method is popular in the meat and poultry industry primarily because less labor is involved. Figure 2 A portable high-pressure, low-volume cleaning unit that can be used where a centralized system does not exist. This unit is...

Incubation Room

A standard incubation room for natto has a door with an internal dimension of length 2.4 m x width 3.3 m x height 2.1 m. The roof has a shape of inverted bottom of a boat, with a vent in the center. The door should be a double-door design. The wall should be surrounded with wood panels or stone. Mortar is put on the surface or it is lined with iron sheets. If insulation is needed, a 25-cm thick layer of sawdust, fiberglass, or polystyrol can be used. Inside the room, shelves are installed on...

Molds Fermentation

Molds are multicellular microorganisms (eukaryotic cells) with mycelial (filamentous) formation. They possess tubular cells that range from 30 to 100 Am in diameter, called hyphae, which form a macroscopic mass called a mycelium. These microorganisms are characterized by the display of a variety of colors and are normally recognized by their mildewy or fuzzy, cottonlike appearance. They can develop numerous tiny spores that are found in the air and can be spread by air currents. Molds normally...

Lactic Acid Bacteria

When raw milk is left at room temperature for some time, a microflora will develop in which lactic acid bacteria generally dominate. These bacteria acidify the milk and, as a consequence, inhibit the growth of other bacteria. Concomitantly, they give the milk a pleasant flavor. This spontaneous fermentation has been the basis of several fermented dairy products in history. The discovery of the role of lactic acid bacteria in milk fermentation paved the way for their isolation, characterization,...

Organic Acid Preservatives

Among the most commonly used food preservatives are sorbates, benzoates, and propionates. Propionates have traditionally been the preferred preservative for bread they inhibit molds and Bacillus spores, but not yeasts (30). Sorbate is more effective than propionate it inhibits both molds and yeasts, and is used in a wide range of food products, including fine bakery products and confectionary (31) more recently sorbate has been included on the so-called positive list laid out by the European...

Ivpickled Nonfermented Jalapeino Peppers

Jalapeiio peppers that are most widely sold in producing countries, such as Mexico are pickled nonfermented products. They are sold in different can sizes and consist of whole cut peppers, mixed with scalded onions, carrots and mushrooms, with vinegar to which spice has been added. (Fig. 2). The main difference between this product and fermented peppers is that the raw material is fresh peppers or peppers preserved with salt (brine). According to its acidity, the product is then heat-treated...

Treatment of Defatted Soybeans

The main purpose of treating defatted soybeans is to denature the soybean proteins to a form so that it is more suitable for the protease from the starter to digest or hydrolyze (primary denaturation), without the presence of ''native'' proteins (6). However, the soy protein should also not be denatured to an extent that it is not easily utilized by the protease (secondary denaturation.) In order to avoid over-denaturation, the current practice is to steam the soybeans for less than one hour,...

Mesophilic Dlstarter Culture

Mesophilic undefined starters with mixed species are used in the production of semihard cheese. This kind of starter is composed of several strains of lactic acid bacteria that give rise to the development of a dynamic population during the manufacture and ripening of cheeses. They are referred to as DL-starters because of their composition. The bacterial strains are of four different kinds namely, the two main acid producers, Lactococcus lactis subsp cremoris (Lc. cremoris) and Lc. lactis...

GABA

GABA tea is a new type of tea with health benefits, manufactured in anaerobic condition. GABA tea is so called because it contains high concentration of g-aminobutyric acid (GABA). In animal and human studies, g-aminobutyric acid has a hypotensive effect another metabolite in anaerobic fermentation of GABA tea is alanine, which has an alcohol-detoxifying effect. GABA tea is truly a natural healthy beverage (16-18). B. Development of Tea Culture Activities, Tourism, and the Recreational Tea...

Soy Nuggets

Soy nuggets are known as''douchi'' in mandarin Chinese, or '' toushih in Cantonese. They are made by fermenting whole soybeans with strains of Aspergillus oryzae, although some other strains of fungi or bacteria may also be responsible. The product usually has a flavor similar to soy sauce or jiang. Because the color of the beans is often black after fermentation, the product is also known as salted black beans in the West. Soy nuggets are commonly used as an appetizer to be consumed with bland...

Technological Aspects Of Dough Fermentation

Very good accounts of the fermentation and preparation of doughs, describing the large variation in time needed to produce them while taking into account the mechanical and chemical methods of preparing dough, are already provided by textbooks (20-22). It can be deduced from this literature that all these processes have both advantages and disadvantages in the production of certain bakery products. For example, the short preparation time (2 hr) required for wheat flour doughs without bulk...

Industrial Food Fermentations

With the discovery of microorganisms, it became possible to understand and manage food fermentations. Methods for isolating and purifying microbial cultures became available in the 19th century. Sterilization or pasteurization of the raw materials prior to inoculation with well-defined cultures allowed the fermentation processes to be managed with little variation. The use of defined cultures became the industrial standard in breweries by the 19th century. During the 20th century, the wine,...

Plant Layout

The objective of the layout was to permit an orderly flow of material through the plant during processing, give enough elbow room for the processing staff during processing and cleaning of equipment, and prevent cross-contamination of maize with fermented dough or the final product. The processing hall is divided into the main hall, the milling room, the fermentation room and the cooking section. This layout reduces noise pollution of the plate mill by its seclusion in a milling room, the...

Sourdoughs

A number of different sourdoughs and methods of fermenting them have been described in the literature (6,27-33). Common to all sourdoughs is the proliferation of lactic acid bacteria that accompanies the formation of organic acids, predominately lactic acid and acetic acid. The properties of the respective sourdoughs are the result of that metabolic activity, which in turn can be influenced by production conditions. The way in which microorganisms and the process variables of sourdough...

Commercial Kimchi Production And Trade A Commercial Kimchi

The commercial production of kimchi started in the 1960s when it was supplied to the Korean army stationed in Vietnam. Kimchi production has increased considerably for commercial purposes since the 1970s. Kimchi was one of the official foods selected for the 1988 Seoul Olympic games, the 1992 Barcelona Olympic games, and the 1996 Atlanta Olympic games. Koreans consume 1526,000 tons of kimchi per year, of which 115,000 tons 7.5 was produced by commercial kimchi manufacturers in 1992, increasing...

Preservation Methods

Since industrialization, urbanization and changing lifestyle started to demand for longer shelf life, the use of sorbate and propionic acid has been the main choice. Today's consumer, however, expect less use of synthetic preservatives but still they require food to be free from microbial growth, toxins, and other quality-deteriorating factors. Meanwhile, product freshness and sensor qualities must be preserved. The problem for the food industry is to fulfill these demands for minimum changes...

Biochemical And Nutritional Changes During Fermentation

During kenkey production, the pH reduces from about 5.9 to 4.2 during 24 to 48 hours of steeping. After milling and addition of water, the pH increase to about 5.3 but drops rapidly during fermentation to 3.7 after 24 to 48 hours 13 . As the reduction in pH is observed, an increase in titratable acidity is also recorded from about 0.7 to 2.2 mg NaOH g_1 after 2 days of maize dough fermentation 29 . The main carboxylic acids produced during the fermentation of maize dough are D L-lactic acid and...

Distillation A Malt Whisky

The production of malt whisky involves batch-distillation of the fermented liquid in two copper pot stills, namely the wash still and the spirit still Fig. 3 . The contents of the fermentation vat are transferred to a large wash still, of capacity 15,000 to 30,000 liters, and boiled for 5-6 hr to produce a distillate the low wines that contains 20-25 ethanol 35-45 proof British . The low wines are distilled in the spirit still to produce the following three fractions 2. Whisky potable spirit...

Summary

Packaging is a very important element in the manufacture of semisolid fermented dairy products and significantly affects the shelf life, quality, and safety of the products. Critical aspects in the design of a packaging system include selection of appropriate materials that meet required barriers to moisture, gases, and light, and are environment-friendly geometry and construction to protect product from environmental factors and physical deformation, and provide consumer convenience and...

Strongly Acid Cleaners

These compounds are corrosive to concrete, most metals, and fabrics. Strongly acid cleaners are used in cleaning operations to remove encrusted surface matter and mineral scale frequently found on steam-producing equipment, boilers, and some processing equipment. Strongly acid compounds used for cleaning operations in meat and poultry plants include hydrochloric muriatic , hydrofluoric, sulfamic, sulfuric, and phosphoric acids. Nitric and sulfuric acids are not used in manual cleaners because...

Kefir

Pencil Drawings Semi Trucks

Kefir has a long history in Russia, where it originated, but is now manufactured and consumed in several other parts of the world as well 1,13 , though the per capita consumption remains high in Russia at 4 to 5 kilograms. The name kefir is derived from the Turkish term kef or from kefy in the Caucusus region implying pleasant taste 4 . Kefir is a viscous pourable liquid, with a smooth, slightly foamy body and whitish color. It is yeasty, acidic, mildly alcoholic, refreshing, and slightly...

Spoilage Of Bakery Products

The spoilage of bakery products is mainly caused by molds and yeasts and only occasionally by bacteria. This is due to a reduced, water activity and for some products, also a reduced pH. The spoilage fungi are fastidious organisms, and a shelf life of only 2-3 days may be expected for products like unpreserved wheat bread, especially if the hygiene in the factory is not sufficiently high. Besides the repelling sight of visible growth, fungi are responsible for off-flavor formation and the...

Conclusion

Tempeh is a fermented food of Indonesia with a long, storied past and great potential yet uncertain future in the United States. Largely made on a small, cottage industry level where self-sufficiency is valued over financial gain, Indonesian tempeh is made today in thousands of shops all across this island nation using very rudimentary fermentation methods. Tempeh is an ethnic food that deserves the pride that Indonesians now place in this most unusual product. Transferring this cottage...

Processing Technology

Dry Cured Ham Cross Section

Traditionally, pigs were reared at home and slaughtered by the end of November or early December so that hams could be salted and then left for salt diffusion during the coldest months. During the spring and summer, hams were ripened and dried, becoming ready for consumption by autumn almost one year of total process . The production sites were usually located in the mountains, with cool and dry weather conditions favoring this process. The windows of the rooms were opened or closed depending...

Proteolysis Leads to Peptides and Free Amino Acids

Because the concentrations of free amino acids and peptides are very low in milk, the starter cultures depend for growth in milk heavily on their proteolytic systems. The degradation of milk proteins caseins leads to peptides and free amino acids, which can subsequently be taken up by the cells 99,100 . Proteolysis is initiated by a single cell-wall-bound extracellular proteinase Prt , which can be either chromosomally or plasmid-encoded. Most dairy lactic acid bacteria strains contain such an...

Koumiss Kumys

Koumiss is a frothy beverage with a grayish-white color, a refreshing taste, and a characteristic aroma 1 . The name koumiss is derived from the Kumanes tribe of the central Asian steppes, where it is believed to have originated many hundreds of years ago and was a common drink of the Tatar and Mongol tribes. Traditionally, this product was obtained by fermentation in a vessel made of horse-skin 35 , but now it is made on a large scale in some parts of the world from mare's milk. It is an...

Probiotics In Semisolid Dairy Foods A Introduction

In the early 1900s, Nobel prize-winning scientist Elie Metchnikoff was the first to propose that acid-producing organisms in fermented dairy foods offered a prolongation of life by preventing fouling in the large intestine 34 . From his idea evolved the idea of functional foods as a marketing term in the 1980s. This term is used to describe foods fortified with ingredients capable of producing health benefits. The trend for healthful foods is becoming increasingly popular with consumers because...

Packaging Materials

Packaging is the main preservation technology in the commercialization of food products. Through the correct selection of both materials and packaging technology, food freshness can be maintained to obtain the required shelf life. Traditionally, a package is considered a passive barrier that retards the adverse effect of the environment on the packaged product. The most visual example of such a package is a glass jar. However, packaging science and technology is in constant evolution, and...

Kimchi Fermentation with Starter Cultures

In the hope of better quality control, there have been several attempts to ferment kimchi using starter cultures. Lac. plantarum, Lac. brevis, Ped. cerevisiae, and Leu. mesenteroides isolated from kimchi were used as starters 33 . The starter cultures inoculated into kimchi increased fermentation rates compared to the control kimchi, even though the fermentation period was shortened by about 24 hours compared to the control at 25 C. Also, these studies showed that the sensory test score was...

Clarification Separation

Disk Stack Separator Cross Sections

If raw milk is the starting material in the yogurt or sour cream processing facility, separation is necessary because the starting materials must contain specified fat levels. Separation of milk into skim and cream fractions must be conducted in approved equipment. Centrifugal separators not only separate the cream and skim fractions but remove solid impurities from milk. Milk is forced through discs with vertically aligned distribution holes at a specific distance from the edge of the disc...

Fyx

Tofu Fermentation Process

Figure 4 Flowchart for making stinky tofu. From Ref. 4. increased gradually to about 7.5. The total bacterial count fluctuated between a light decrease after 10 weeks of fermentation. In the first week of the fermentation period, the pH value of tofu slices in the stinky tofu brine dropped from 6.5 to about 4.6 due to the production of lactic acid and growth of the lactic acid bacteria. Thereafter, the protein in the tofu was hydrolyzed by the microbial proteases to form amino acids, followed...

Pretreatment of Subingredients and Mixing Process

As shown in Fig. 1, the brined baechu cabbage is spiked with premixed subingredients of spices, seasonings, and other things. Red pepper powder, garlic, ginger, and green onions are the main spices added to the kimchi. These subingredients should be selected for their good quality, as they can substantially impact the final quality of the kimchi. For instance, appropriate amounts of capsaicin, the sugar content, and the color intensity of the red pepper are important factors in selecting a...

Rhizopus Chinensis

Rhizopus Chinensis

Sufu Chinese soy cheese and stinky tofu chaotofu are block-type fermented soy foods. In the manufacture of these fermented foods, sufu utilizes mainly mold s , whereas stinky tofu utilizes mainly bacteria. Molds multiply under aerobic condition and produce amylase, protease, and other hydrolases. These enzymes then hydrolyze their substrates. However, molds do not grow under anaerobic conditions but can use the enzymes they produced to hydrolyze their substrates. Therefore, under aerobic...

Packaging and Weighing

Inoculation Room Natto

Inoculated beans are put into the proper container for fermentation. This process is characteristic of natto manufacturing. Because the inoculated beans have to be put in one by one, the packaging and weighing are very labor intensive. The process has to be mechanized Fig. 5 . Figure 4 Inoculation of Bacillus natto. Figure 4 Inoculation of Bacillus natto. In the past, the package material was rice straw. Later, thin wood slices of fir or cypress was used. Nowadays, bags with perforated inner...

Meat Ingredients

Because of the warm, humid conditions normally utilized for fermentation of semidry sausages, meat ingredients must be of very high quality. Fermentation encourages microbial growth and accelerates chemical reactions, both of which have potential to affect final product quality and may even result in spoilage. Fresh meat with no microbiological or chemical age is essential for manufacturing fermented sausage. If initial microbiological counts on meat are high, undesirable growth may occur...

Hamanatto A Introduction

Japanese hamanatto is a fermented, intermediate-moisture soybean that belongs to a group of very similar, fermented soybean products that are sometimes called soy nuggets. It is made by fermenting the cooked soybeans with Aspergillus oryzae followed by soaking in a brine or soy sauce, and then dried. It is consumed directly in Japan. It differs from the ordinary natto with its sticky substance on its surface. In Japan, various similar names are used with this type of products such as daitokuzi...

Fermented Whole Soybeans

Ordinary natto is a typical Japanese fermented whole soybean product. Its sticky muci-lageous substance on the surface of soybeans is its characteristic. It is produced by fermenting cooked soybeans with Bacillus natto for a brief period. It has a short shelf life. Table 44 lists the basic steps in the manufacture of ordinary natto. For detailed information on ordinary natto, please refer to the Chapter 30 in this book and the references in this chapter 34,36,41 . Hama-natto is fermented whole...

Future Trends

The market for probiotic drinks is booming, and clinical work with probiotics continues to provide support for their benefits. Yakult, from Japan, is the world's largest probiotic dairy beverage, followed by Actimel from Danone 81 . The dividing line between yogurt and cultured milks is becoming thinner. Probiotic strains may become the sole fermenting agents in yogurt and fermented milk 82,83 . Biogaia and Farm Produce Marketing Ltd. have signed an agreement to market and sell drinkable yogurt...

Molds Used for Dairy Products

Penicillium Camemberti Mold

The use of molds such as Penicillium roqueforti and Penicillium camemberti has a long history in the production of cheese, and their use as starter cultures goes back to the beginning of the 19th century. P. roqueforti is used as a secondary starter culture in the production of blue-veined cheeses, but it may also occur spontaneously in a number of other foods, and for some types of cheeses it is regarded as a contaminant. The fact that P. roqueforti is able to grow at high NaCl and low O2...

The Fermentation Of Vegetables

At present only cabbage sauerkraut and Korean kimchi , cucumbers pickles , and olives are of real economic importance. In this chapter, the discussion is focused on these vegetable products. In addition to these vegetables, fermented carrots, the potential new products, and fermented bamboo shoots will be described. Sauerkraut is a fermented product made from fresh cabbage. In the cabbage fermentation process lacti acid bacteria are favored. The addition of 2.25-2.5 salt restricts the...

Douchi A Introduction

Flow Chart Douchi Fermentation

Douchi is a Chinese fermented soybean product. It is very similar to the Japanese hamanatto. Douchi can be made from black soybean preferred , or soybean. One kind of douchi, sometimes called yinshi, is the dried residual black soybean koji starter in the manufacturing of Yinyui pot bottom oil or pot bottom excrement, one kind of soy sauce made from black soybean, Glycine max L. merri var. o au . Good-quality douchi is made by proper control of the bean soaking and steaming processes so that...

Steamed Bread Mantou

Steamed bread is common in the Chinese community. Plain steamed bread is consumed as the major staple in the northern provinces of China. However, stuffed steamed breads are Table 36 Various Breadmaking Processes Straight dough baking process Weigh out all ingredients Add all ingredients to mixing bowl Mix to optimum development First fermentation, 100 min., room temperature, or at 27 C for 1.5 hr Punch Second fermentation, 55 min, room temperature, or at 27 C for 1.5 hr Divide Intermediate...

Stabilizers

The set yogurt gel structure results from an acid-casein interaction in which casein micelles at or near their isoelectric point flocculate and the colloidal calcium phosphate partially solubilizes as acidity increases. During the fermentation of milk, the pH gradually declines to around 4.5 and destabilized micelles aggregate into a three-dimensional network in which whey is entrapped 43,44 . Appearance of whey on the surface of yogurt gel is due to syneresis, separation of serum from curd. In...

Anticancer Effect of Kimchi

Kimchi showed antimutagenic activities against aflatoxin B1 in Ames test, SOS chromotest in vitro 94-96 . The kimchi extract also showed antimutagenic activity in the Drosophila wing hair spot test in vivo 97 . Kimchi also exhibited anticlastogenic activity in mitomycin C-induced mice, using the in vivo supravital staining micronucleus assay 98 . C3H 10T1 2 cells are mouse embryo cells that form foci in culture media when exposed to carcinogens. The foci, developed as type II and type...

Chaotofu Or Stinky Tofu

Chaotofu or stinky tofu is one of the traditional Chinese soy foods. It is still made by the traditional, household, open-fermentation method. The tofu is soaked in special stinky brines for 4-6 hr, to conduct the brief fermentation. The stinky brine is made by letting the various ingredients in the brine carry out a natural fermentation with production of a strong stinky odor. These ingredients can be a various vegetables such as amaranth leaves, bamboo shoots, and winter wax melon, b salted...

Yogurt Fermentation

Yogurt fermentation is a homolactic fermentation. Glucose metabolism by ST, LB, and Lb. acidophilus proceeds by the EMP pathway. Lactose utilization in ST, LB, and bi-fidobacteria involves lactose transport into the cells via cytoplasmic proteins permeases . This translocation of lactose takes place without its chemical modification. This unphos-phorylated lactose is hydrolyzed by h-galactosidase to glucose and galactose. Glucose is catabolized and galactose is secreted from the cells 23,53 ....

Microorganisms and the Characteristics of the Fermentation

Kimchi Fermentation Temperature

The fermentation of kimchi is carried out through a naturally controlled brining process. During kimchi fermentation, microorganisms should be tolerant to salt, acidity, anaerobic conditions, and endogenous antimicrobial compounds in the ingredients. The main microorganisms involved in kimchi fermentation are LABs, which are facultative anaerobes, microaerobes, or anaerobes. Several factors, such as salt concentration, temperature, pH, microorganism population, and air exposure control the...

Dongchimi

Dongchimi, a whole oriental radish 12-15 x 7-10 cm kimchi, requires a large quantity of seasoned water. Whole radishes are salted with dry salt and then rinsed. The rinsed uncut radishes are mixed with other ingredients shown in Table 3 in a large quantity of 3 to 4 percent brine solution and then fermented in a crock, completely immersed in the mixed ingredients and water. Green onion, garlic, and ginger are the main subingredients for dongchimi preparation. However, pears, fermented green...

Conclusions And Perspectives

At present, choices of packaging materials and methods are primarily based on practical experience and or empirical methods. However, it is crucial to commercial viability to target research and development activities on interactions between packaging, the surrounding headspace, and the product. Different types of cheeses call for different packaging concepts hence, in-depth knowledge is required of the most important quality changes taking place in the various types of cheese in order to...