Bread flavoring from

The richness of bread is directly associated with the fermentation of the dough. The rich bread flavor is supposed to be due to split-protein products produced during fermentation. The flavor of flour is a very different thing from the flavor of rich bread. The bread flavor is something very complex and delicate as shown by the fact that any small change in manipulation changes the flavor of the bread. 

Salt. Salt adds flavor but also controls the yeast by slowing the fermentation process, keepir the bread matrix from overstretchir and subsequently deflating. For a proper rise, you have to get the salt-to-yeast tario r ht. Plain table salt will do, though some prefer the flavor of sea salt. 

CY Chang, LM Seitz, E Chambers IV. Volatile flavor components of breads made from hard red winter wheat and hard white winter wheat. Cereal Chem 72 237-242, 1995. 

The aroma of fmit, the taste of candy, and the texture of bread are examples of flavor perception. In each case, physical and chemical stmctures ia these foods stimulate receptors ia the nose and mouth. Impulses from these receptors are then processed iato perceptions of flavor by the brain. Attention, emotion, memory, cognition, and other brain functions combine with these perceptions to cause behavior, eg, a sense of pleasure, a memory, an idea, a fantasy, a purchase. These are psychological processes and as such have all the complexities of the human mind. Flavor characterization attempts to define what causes flavor and to determine if human response to flavor can be predicted. The ways ia which simple flavor active substances, flavorants, produce perceptions are described both ia terms of the physiology, ie, transduction, and psychophysics, ie, dose-response relationships, of flavor (1,2). Progress has been made ia understanding how perceptions of simple flavorants are processed iato hedonic behavior, ie, degree of liking, or concept formation, eg, crispy or umami (savory) (3,4). However, it is unclear how complex mixtures of flavorants are perceived or what behavior they cause. Flavor characterization involves the chemical measurement of iadividual flavorants and the use of sensory tests to determine their impact on behavior. 

Another group of natural flavoring ingredients comprises those obtained by extraction from certain plant products such as vanilla beans, Hcotice root, St. John s bread, orange and lemon peel, coffee, tea, kola nuts, catechu, cherry, elm bark, cocoa nibs, and gentian root. These products are used in the form of alcohohc infusions or tinctures, as concentrations in alcohol, or alcohol—water extractions termed fluid or soHd extracts. Official methods for their preparation and specifications for all products used in pharmaceuticals are described (54,55). There are many flavor extracts for food use for which no official standards exist the properties of these are solely based on suitabiUty for commercial appHcations (56). 

Lactic Acid B cteri. The lactic acid bacteria are ubiquitous in nature from plant surfaces to gastrointestinal tracts of many animals. These gram-positive facultative anaerobes convert carbohydrates (qv) to lactic acid and are used extensively in the food industry, for example, for the production of yogurt, cheese, sour dough bread, etc. The sour aromatic flavor imparted upon fermentation appears to be a desirable food trait. In addition, certain species produce a variety of antibiotics. 

Many nitrogen- and sulfur-containing heterocycles have been identified in the aroma fractions of foods [214]. In roasted products (e.g., coffee) and heat-treated foods (e.g., baked bread or fried meat), these heterocycles are formed from reducing sugars and simple or sulfur-containing amino acids by means of Maillard reactions [215, 216]. Their odor threshold values are often extremely low and even minute amounts may significantly contribute to the aroma quality of many products [217, 218]. Therefore, N- and N,S-heterocyclic fragrance and flavor substances are produced in far smaller quantities than most of the products previously described. 

The /Invar of an edible substance is the combined sensation of taste and odor as perceived by the eater/drinkcr of that substance. Although the components Jlufood substances, the full aspects of flavor require intimate contact between substance and consumer. The odors emanating from a bakery tend to be richer and more pleasant than the bread itself the flavor of coffee seldom attains the richness of aroma lhat one perceives in the vicinity of a coffee roasting plant. Flavor is a unique combination of nerve impulses on the brain centers as the result of actions upon receptors located on the longue and in the lining of [he nose. II is thus the result of interaction between the food substance and the consumer. 

Proteins are important from the nutritional and technological points of view. Proteins affect every property that characterizes a living organism, and they play different roles in the human body. Proteins are also very important in food technology and are responsible for many food properties. The physical properties of proteins and their interactions with other components contribute significantly to the functional behavior and quality of several food products, such as cheese, bread, and meat products (9). An overview of the functional roles of proteins in different food systems is presented in Table 2. Food preferences by human beings are based not on nutritional quality but on sensory attributes to the food, such as appearance, color, flavor, texture, and... 

A first approach to analyze such volatiles is the application of the AEDA on extracts prepared by dynamic headspace extraction. An apparatus used for the extraction especially of solid foods is shown in Figure 5 [55]. The powdered material is placed into a rotating cylinder and the volatiles are continuously flushed onto a polymer material (Tenax( )) by using a stream of helium (1 L/min). After 3 hr the volatiles are desorbed from the polymer by elution with a small amount of diethyl ether and evaluated by AEDA after concentration. Since different yields may change the composition of the volatiles during headspace extraction [7], it is essential to sensorially evaluate the flavor of the extracts in comparison with the food flavor itself. The following examples show applications of this method on fresh and stored wheat bread crust [55] and on fresh rye bread crust [P. Schieberle and W. Grosch, unpublished results]. 

The carob, or locust bean, tree, Ceratonia siliqua L., is indigenous to Mediterranean shores. It produces flat pods, known as St. John s bread, eight to twelve inches long, from which the seeds are removed and processed to yield locust bean gum. The deseeded pods are dried, broken, and sold as "kibble", which can be roasted and ground to provide a nutrient flavoring agent. 

Sample b c roasted (bread, coffee, peanut, walnut, malt), burnt, popcorn, slightly rancid, heated cooking oil Sample ds heated cooking oil, deep-frying fat, solvent, old paint Since the panel found no difference between samples b and c in the triangle test, it was not possible to ask for two distinct "profiles" in the descriptive test. However, it was evident that samples b and c were the most attractive oils from a flavor point of view. There were similarities with sesame oil and Swedish crispbread. 

Amino acid specific Maillard products were isolated from the extracts by preparative GC or HPLC and identified by MS-, IR-, 1 H- and c-NMR-spectroscopy. Proline derived components are important constituents in bread, malt and beer. More than 120 proline specific Maillard products were characterized. Cysteine and methionine derived components were predominant in roasted coffee and meat flavors. Thirty cysteine- and twenty methionine-specific Maillard products were identified for the first time. 

The aroma extract dilution analysis was applied to extracts obtained from the crumb of wheat bread. Twenty nine odorants were detected and the flavor compounds responsible for the odor notes identified (Schieberle, P. Grosch, W. in preparation). The 12 aroma compounds having the highest FD-factors are presented in Table IV. 

The flavor compounds of the crust from the chemically leavened model bread were then compared to those recently identified (6) in the crust of a standard wheat bread which was leavened by addition of yeast (Table I). One striking difference was that Acp (No. 16), which showed the highest FD-factor in the yeast-leavened bread showed a very low FD-factor in the chemically leavened bread. This indicated, that the flour contained only minor amounts of the precursor (s) for the formation of Acp. On the other hand, 2(E),4(E)-decadienal, 2(E),4(E)-nonadienal, l-octen-3-one and 2(Z)-nonenal, which are undoubtedly formed by a heat-induced oxidative degradation of the flour lipids, became predominant odorants in the chemically leavened compared to the yeast-leavened bread. 

While several reviews on the role of ingredients are available, none of these describe the flavor chemistry of cracker sponge and dough (2, 3, 4, 5). However, some insight into the chemistry of cracker aroma can be obtained from examination of products that have a "cracker-like aroma" such as white bread crust. 

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