References

Cheese and Fermented Milk Foods. 3rd edition, Vol. I & II. F.V. Kosikowski, Wesport, Connecticut. 1997. 2. P Walstra, TJ Geurts, A Noomen, A Jellema, MAJS van Boekel. Dairy Technology Principles of Milk Properties and Processes. Marcel Dekker, Inc. New York. 1999. 3. E Spreer. (A Mixa translator). Milk and Dairy Technology. Marcel Dekker, Inc. New York. 1998. 4. R Jenness. Composition of milk. In Fundamentals of Dairy Chemistry. (NP Wang, R Jenness, M Keeney, EH...

Labeling of Tea Leaf Packages

Labeling requirements for tea leaf in Taiwan are not strict. This is mainly due to the various kinds of tea produced in Taiwan that are used for local consumption and for marketing. Correct and clear labeling of kinds of tea, manufacture date, location of production, manufacturer, brewing and consumption methods can help establishment of brand names and marketing. There is absence of strict requirements for shelf life. Some indicate 1 or 2 years. Theoretically, a clear message about consuming...

Packaging And Storage Of Partially Fermented

In tea manufacture whether of green tea, partially fermented tea, or fully fermented tea fresh tea leaf is plucked, transported to the factory, and finish-processed with the final step of drying to the final product. This raw tea or roughly processed tea undergoes change in moisture content from about 75 (wet weight basis) moisture is rapidly reduced to below 5 . Because raw tea or roughly processed tea go through such a drying process, it is a product with very low moisture and with water...

Outlook for Modern Large Scale Wheat Sourdough Production

The concept for a plant capable of manufacturing liquid sponges developed by the Reimelt company constitutes a new approach to the development of large wheat sourdough plants. Reimelt has developed a plant for the fermentation of liquid sponge, which constitutes a technical breakthrough in sponge production. The capacity of the liquid sponge plant is 2000 kg hr at a fermentation time of 4 hr. The plant is operated with wheat flours with a high gluten content (wet gluten > 30 ) and pronounced...

Cereal As A Substrate

Cereals are, in general, a good medium for microbial fermentations. They contain a high level of carbohydrates, which can be used as a source of carbon and energy by microbes in fermentation (Table 1). Most of the carbohydrate in cereals is present as starch and only available for microbes after amylolytic hydrolysis. The level of free sugars in fully matured sound grains is relatively low, but the 2-5 free sugars supports the initiation of the fermentation process. The content of free sugars...

Sauerkraut

The term sauerkraut literally means sour (sauer) cabbage (kraut). It is a traditional German fermented vegetable product that has spread to other cultures and is used in food preparations. The sequential growth of lactic acid bacteria in sauerkraut has long been recognized. Each lactic acid bacterium dominates the fermentation until its end product becomes inhibitory for its own development and creates another environment suitable for Table 49 Production Scheme for Tempeh Whole, clean soybeans...

Quality Characteristics of Chingcha Oolong Type

The Chingcha (Oolong-type tea) group of tea has many varieties. Due to varietal and procedural differences in processing, considerable quality differences exist among the different Oolong teas. As in the case of white tea, variations in tea leaf plucked at different seasons affect its quality. Spring and winter teas have the best quality, followed by the autumn tea, and then the summer tea, which is poorest, with a more bitter taste and poor aroma. The exception is Pomfeng tea (also called...

Amino Acid Converting Enzymes AACEs

Amino acids are the precursors of various volatile cheese flavor compounds that have been identified in cheese (93,94). They can be converted in many different ways by enzymes such as deaminases, decarboxylases, transaminases (aminotransferases), and lyases (Fig. 7). Transamination of amino acids results in the formation of a-keto acids that can be converted into aldehydes by decarboxylation and, subsequently, into alcohols or carboxylic acids by dehydrogenation. Many of these components are...

Nutritive Value And Importance In The Diet

The nutritive value of kenkey is basically dependent on the maize from which it is made and the processing technique used in production. Maize contributes significantly to the total calorific and protein content of the diet of people who consume it as a staple in Ghana and is richer in protein than other staples such as cassava, coccoyams, yams, and plantain. However, the traditional maize varieties are deficient in lysine, tryptophan, and B vitamins (2). It has been estimated that maize...

Biochemical Changes During The Process

Many biochemical changes have been reported during the processing of dry-cured ham, most of them bring a consequence of enzymatic reactions. Some of these changes are restricted to the beginning ofthe process such is the case with nucleotide breakdown reactions or the glycolysis-related enzymes and subsequent generation of lactic acid. Proteolysis and lipolysis constitute two of the most important enzymatic phenomena, responsible for the generation of compounds with direct influence on taste...

Formation Of Acid Coagulum

The mesophilic fermentation slowly converts lactose to lactic acid, which leads to increased acidity of the cheesemilk. The acid development causes several physico-chemical changes in the milk (13), primarily based on the conversion of casein from micellar form to a casein matrix. It is generally recognized that colloidal calcium phosphate connect and bridge casein submicelles within the casein micelle. Most or all of the colloidal calcium phosphate is solubilized by the time that acidification...

Accelerated Processing Of Drycured Hams

Many attempts have been made to accelerate the process, especially in country-style hams. Most of them try to accelerate the penetration and diffusion of salt into the hams, such as by boning and skinning of hams (84-86), mechanical tenderization through blade penetration prior to dry cure (87), tumbling in a revolving drum with baffles (88), or the direct use of nitric oxide instead of nitrate or nitrite (89). In other cases, more intense biochemical changes through papain injection (90),...

Free Whey

Whey syneresis on top of the sour cream in the package is considered a significant quality defect. There are three solutions available for solving the problem. 1. Change or increase the concentration of stabilizer. 2. Increase fat content. Higher fat sour creams have a better water-binding capacity. 3. Reevaluate the entire process and eliminate points of product abuse. This would primarily include all steps after fermentation. Cr me fra che, or more correctly cr me fra che paisse ferment e, is...

Yogurt Mix Inoculation And Incubation

The inoculation rate may vary from 0.5 to 6 , depending on the type of yogurt and system set up. For yogurt fermented in the cup (set style), small surges of mix, 20-100 gal may be inoculated at 5 and packaged and then incubated at 43-45 C. Yogurt may reach pH of 4.7 to 4.8 in less than 2 hr and is then sent out of the hot room. If more time is available, the mix can be inoculated at 0.5 to 1.5 , which may take it 6 to 10 hr to reach pH 4.4 to 4.5. The inoculation rate may vary from 0.5 to 6 ,...

Viirole Of Biofilms

Biofilms are microcolonies of bacteria closely associated with an inert surface attached by a matrix of complex polysaccharide-like material in which other debris, including nutrients and microorganisms, may be trapped. When a microorganism lands on a surface, it attaches itself with the aid of filaments or tendrils. The organism produces a polysaccharide-like material, which cements in a matter of hours the bacteria's position on the surface and acts as a glue to which nutrient material will...

Biogenic Amine Biosynthesis

Fermented vegetables usually contain small amounts of biogenic amines. An excessive intake of biogenic amines may cause food poisoning. Biogenic amines may also be considered carcinogens because of their ability to rect with nitrites to form potentially carcinogenic nitrosamines (57). Most biogenic amines present in fermented vegetables are formed by the action of microorganisms through the decarboxylation of amino acids during fermentation. Sauerkrauts and sauerkrautlike products are popular...

Manufacture of Wuyi Yancha

The manufacturing method for Wuyi Yancha is very special and uses fine technology. It includes the essentials for making black and green teas. The manufacture includes proper selection of tea cultivar with optimum plucking, and at the same time, the application of very detailed heating (baking) technology. The degree of fermentation for Wuyi Yancha is more extensive than for Anxi Tieguanyin and Fenghuang Shuixian. It is a tea made with extensive withering and shaking. Except for the highest...

Quality Evaluation And Characteristics Of Partially Fermented

Due to differences in the manufacturing processes, each tea has its own quality characteristics. These differences in quality characteristics subsequently affect consumer preference significantly and also account for the wide variations in unit prices. It is difficult to describe the general characteristics of different teas. However, the differences can be discriminated by sensory evaluation. In other words, different groups of tea have their own characteristics. Green tea is typical example...

Basic Principles Of Cheesemaking

The first step in making cheese is coagulation of milk. Milk can be coagulated by the action of rennet enzyme or by acidification. The coagulum has a natural tendency to syneresis contraction and expelling of whey (i.e., water and water-soluble compounds of the milk (Fig. 1). Larger particles such as fat globules and bacteria will be retained in the shrinking coagulum, the cheese curd. The syneresis can be accelerated by cutting up the gel and by heating. The resulting firm curd can be pressed...

Changes in Characteristic Flavoring Compounds

The characteristic flavoring compounds of natto beans are produced during fermentation. The umami compounds are mainly the protein hydrolysates. During natto fermentation, about 50-60 of the proteins soybean are hydrolyzed to water-soluble nitrogenous compounds, of which 10 is amino acids. Water-soluble nitrogen increases by 228 , amino nitrogen by 757 , and ammonia nitrogen by 900 (dry wt. basis) (1). The free amino acids profile also changes considerably. The freeing rate ranges from 2 to 26...

Info

A baker's yeast preparation, through the electron scanning microscope, reveals a multitude of distinctive cells (Fig. 1), ovoid in shape. Some of them have buds or the scars that they have left. They vary in size from 6 to 8 Am. One cubic centimeter of compressed yeast with a 30 dry matter content contains about 10 billion cells. Transmission electron microscopy reveals the following ultrastructure (Fig. 2), from the outside towards the inside The cell wall. Composed of glucans and mannans...

Selection and Formulation of the Raw Ingredients

The quality and species of the major ingredients (Korean baechu cabbage, Brassica cam-pestris sp. Pekinensis or oriental radish, Raphabus satirus L.) may significantly affect the product characteristics of kimchi. For example, only carefully selected baechu are used for baechu kimchi. The best baechu fit for a high quality kimchi has a compact structure, an oval-shaped head, white tissue, and green leaves. Essential to this selection process are the evaluations among the cabbage varieties for...

Aflata Preparation and Mixing

A portion of the fermented dough is made into a slurry by adding two or three parts of water and cooked with continuous stirring into a sticky gelatinous paste known as aflata. During this process, salt is added in the case of Ga-kenkey. The aflata is mixed thoroughly with a portion of the uncooked fermented dough using wooden ladles and allowed to cool. The ratio of aflata mixed with uncooked dough depends on the type of kenkey being produced and the preference of the consumers. Amongst the...

Semisolid Cultured Dairy Products

Semisolid Cultured Dairy Products Principles and Applications Dilip Patel and Marcia Walker 8. Sour Cream and Creme Fraiche Lisbeth Meunier-Goddik 9. Yogurt and Sour Cream Operational Procedures and Processing Equipment Stephanie Clark and Virginia Cristina Plotka 10. Fromage Frais Lisbeth Meunier-Goddik 11. Semisolid Cultured Dairy Products Packaging, Quality Assurance, and Sanitation

Salami Mincing and Mixing Operations

In order to extract a good quantity of the salt-soluble proteins, the cutting of the various fractions, the addition of ingredients and additives, and the mixing of the various components can be done on one or several machines, each having a specific function. The most complex line (several machines) involves an initial breaking up of the meat using a roughing machine the final mincing of the particles takes place in a mincer, and the addition of ingredients and additives in a mixer. This line...

Maturation

The whiskey obtained directly from the distillation step is colorless and has a harsh taste, and therefore a long period of maturation is essential to develop the final flavor, which is a major determinant of whiskey quality. The diluted raw spirit is stored in air-permeable oak barrels (casks) in temperature-controlled government-bonded warehouses for up to 12 or 15 years, sometimes even longer a minimum maturation period of 3 years is mandatory for Scotch and Canadian whiskies. There are five...

Probiotic Features of Starter Cultures

Probiotics are live microbial food supplements that benefit the health of consumers by maintaining or improving their intestinal microbial balance (88). Species of Lactobacillus and Streptococcus have traditionally been used in fluid fermented dairy products to promote human health (89). These probiotic starters may influence the microbial ecology of the host, lactose intolerance, incidence of diarrhea, mucosal immune response, levels of cholesterol, and cancer. Besides the traditional carrier...

Yeasts Used for Dairy Products

For dairy products, yeasts are mainly used in cheese production but may also be involved in the production of fermented milk. Yeasts are primarily used as single-starter cultures but many products are still produced by back-slopping or spontaneous fermentation. A mixture between the used starter culture and a dominant indigenous flora is also seen in many dairy products. Yeasts are in most cases used as secondary starter cultures in order to enhance the aroma production or to facilitate the...

Pasteurization Heat Treatment

The only step in the dairy processing system in which inactivation of pathogenic microorganisms is guaranteed is pasteurization. For this reason, pasteurization is the most critical segment of the processing line. Pasteurization may be conducted in a vat batch system, also called low-temperature long-time (LTLT) or in a continuous high-temperature short-time (HTST) system. Of course, strict sanitation is critical up to and beyond pasteurization to assure the safety and quality of dairy...

Placement in Crocks

The premixtures of subingredients for stuffed tongbaechu kimchi are either stored for ripening or packaged for sale. Traditionally, a large quantity of cabbage heads were used for making kimchi, which were stored in underground potteries for the winter. This practice is called kimjang, and it is a major annual event for the Korean family. Kimjang kimchi is the most traditional way to make baechu kimchi, and it is made between mid-November and early December, depending on the climate of the...

Acidification and Overfermentation

Various biochemical changes occur during fermentation along with the formation of acceptable flavor and texture. However, undesirable fermentation or overfermentation after ripening may produce a poor-quality kimchi, resulting in acidification and cabbage tissue softening (78). Because the raw materials contain sufficient sugar to convert to organic acids, excessive acid can be formed with continuous fermentation by more acid-tolerant microorganisms. The tissue softening problem is associated...

Coagulation

Coagulation by rennet is performed at 32-34 C for 45-50 min. Sheep's milk is very sensitive to rennet and, because of the higher h as-casein ratio, coagulation proceeds faster than with cow's milk (9,10). Alternatively, less rennet is required to obtain the same coagulation time as with cow's milk (11). The use of homemade rennet, made from the abomasa of unweaned lambs and kids (12), was very common when the majority of Feta cheese was manufactured at small plants in mountainous and...

Ixwhiskey Flavor Components

The ethanol content excepted, the most important property, and hence quality criterion, of whiskey is the flavor, which is governed by the presence and relative concentrations of a large number of organic compounds (congeners), which together are less than 1 of the total whiskey composition (6). The detailed congeneric content of three blended types of whiskey is presented in Table 4. In whiskey, carboxylic acids are present acetic acid accounts for 50-90 of the total volatile acid fraction....

Macerating and Amylolytic Enzymes

Macerating enzymes such as b-glucanases (cellulase C1, CM cellulase, b-glucanase, b-1,3-glucanase), pectinases (pectin lyase, polygalacturonase), hemicellulases (xylanase, araba-nase, galatanase) have been characterized as plant tissue degradation enzymes from Aspergillus oryzae in soy bean koji (44). Koji prepared by solid fermentation is superior to that of the liquid culture because of the existence of macerating activity. The macerating enzymes enhance the contact btween the proteolytic...

Starters and Calcium Chloride

Starter culture is usually a combination of lactic acid bacteria at a ratio of lactococci to lactobacilli of 1 3 (e.g., Lactococcus lactis subsp. lactis and Lactobacillus delbrueckii subsp. bulgaricus). In small cheese plants, yogurt is sometimes used instead of pure cultures in this case, acid development is slow (2). Culture is added to cheese milk to a level of 0.5 to 1 (v v) and incubated for about 30 min. Calcium chloride up to 20 g per 100 kg milk may also be added, although this addition...

Classification Of

In general, tea can be classified, based on the degree of fermentation, into four big groups (Fig. 1). These are unfermented tea, partially fermented tea, fully (completely) fermented tea, and post-fermented tea. The so-called fermentation in tea processing is, in fact, a misnomer. In the beginning, tea was considered to undergo fermentation like that of other kinds of fermented foods and beverages, with involvement of microorganisms. Later, it was proved that...

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...

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...

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

Manufacturing Flow Chart Sauce

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

Parameter For Bread Processing

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...