Flavour intensity

A decrease in the perception of taste and aroma of the jellies has been noted when hardness increases, which agrees with Chai et al. (1991) who refer a reduction in the perception of flavour intensity with an increase of gel rigidity which may be related with the available surface area of gel exposed on chewing. 

Flavour research is driven by a need to find compounds that produce desirable flavours. In some cases the improvement that is sought over the natural substance is not flavour intensity or cheapness but chemical stability. 

It is crucial that the consumer finds the product pleasant and comfortable to drink, both during and after heavy physical activity. Sipping small amounts in a laboratory during a day of sedentary work cannot give a valid appraisal and field testing with athletes is essential. Particular aspects needing attention are car-bonation, sweetness, saltiness, acidity and flavour intensity. 

The formation of typical cheese flavours during natural ripening processes are not fully understood yet. The majority of reactions last for an extended time period (months) and comprise oxidative, inter- and intramolecular, enzymatic or microbial (cf. blue cheese) reactions. Substrates are partially very reactive milk-based ingredients which are mainly transformed to volatile flavour intensive compounds like esters, methylketones, aldehydes, lactones and sulphur containing products. The effect of enzymes on the flavour enhancement is also not fully understood. By variation of lipase dosage, reaction time and reaction temperature the production of different flavour notes from milk and butterfat is possible. 

Beef sticks are produced similarly to other dry sausages. Normally, smoke flavourings can be added to the emulsion to provide the optimum smoke flavour intensity. Aqueous base flavourings may also be atomised on the exterior surface during processing to provide a uniform smoke colour. 

Fig, 5,25 Schematic representation of time vs. flavour intensity curves of full fat and fat-reduced or fat-free foods when manipulated and warmed in the mouth [53]... 

Rosin and Tuorila [63] did some comparative research on the odour and flavour intensity of garlic oil and pepper oleoresin in beef stock and in mashed potatoes with no fat and with 10 percent fat content respectively. Using the same dose the intensity of garlic oil was perceived nearly equal in all three foods, i.e. texture (liquid or solid), carbohydrate content and fat content of the foods had almost no influence. In contrast, pepper oleoresin was perceived far better in the liquid beef stock than in the two types of mashed potatoes. In those containing fat, the oleoresin was perceived weaker than in the fat free potatoes. This allows conclusions as to the flavour binding capacity of the fat. 

C.N. DuBose, A. V. Cardello and O. Mailer, Effects of colorants and fla-vorants on identification, perceived flavour intensity, and hedonic quality of fruit-flavoured beverages and cake. J. Food Sci., 1980, 45, 1393-1399. 

Colour and colour uniformity are two of the main parameters that define the direct quality of a vegetable. Colour is often taken as an index of freshness, palatability and nutritional value (Haisman and Clarke, 1975). Colour affects the pleasantness and acceptability of a food and interferes with judgements of sweetness, bitterness, saltiness and flavour intensity (Clydesdale, 1993). 

Taste and odour can be perceived separately but more often than not the two senses are integrated to produce the sensation of flavour. The measurement of taste, odour, or flavour intensity is the subject of at least two different approaches which use different mathematics [15]. Those working with strong flavours are concerned with suprathreshold effects and describe the perceived intensity i as a power factor n of the concentration S so that ... 

Boccorh RK, Paterson A (2002) An artificial neural network model for predicting flavour intensity in blackcurrant concentrates. Food Qual Prefer 13(2) 117-128 Ceballos-Magana SG, de Pablos F, Jurado JM, Martin MJ, Alcazar A, Muniz-Valencia R, Izquierdo-Homillos R (2013) Characterisation of tequila according to their major volatile composition using multilayer perceptron neural networks. Food Chem 136(3) 1309-1315... 

Woo, A.H., Lindsay, R.C Statistical correclation of cjuantitative flavour intensity assessments tmd mdividutil free acid measurements for routine detection and prediction of hydrolytic rancidity off-flavours in butter. J. Food Sci. 48, 1761 (1983)... 

In China some teas, such as Pu-er tea, are made through microbial fermentation and called post-fermented teas. The typical characteristic of these teas is a mouldy or aged flavour the more intense this flavour, the better the quality. Other kinds of tea, such as white, yellow and dark, are produced in small quantities and consumed locally. Further processing of these teas produces scented and brick teas. 

In the foregoing we loosely talked about the intensity of a sensory attribute for a given sample, as if the assessors perceive a single (scalar) response. In reality, perception is a dynamic process, and a very complex one. For example, when a food product is taken in the mouth, the product disintegrates, emulsions are broken, flavours are released and transported from the mouth to the olfactory (smell) receptors in the nose. The measurement of these processes, analyzing and interpreting the results and, eventually, their control is of importance to the food... 

Yolk colour plays a role in consumer acceptance, but the preferred colour varies in different countries. Yolk colour has no relation to nutrient content, flavour or freshness, but is often enhanced in conventional production systems by addition of synthetic pigments to the animal feed. In organic production, synthetic yolk pigments are prohibited and this normally results in paler yolks, but may also lead to greater variability in yolk colour intensity. In many European countries paler yolk colour is perceived by consumers as being associated with less natural production systems, an issue that clearly needs to be addressed by improved consumer information. 

Meat flavour. Meat flavour represents a large number of compounds formed during heating of the product. The flavour development mainly depends on constituents in the fresh meat, for example, fat composition, peptides, glycogen concentration, vitamin content and the heat treatment of the product. Increasing temperatures increase flavour development. According to Andersen (2000), the intensity of pork flavour has decreased during recent years, most probably as a result of the production of pork with a minimal content of intramuscular fat. 

Alternatively, hydrogen sulfide could be produced alongside ammonia and acetaldehyde by the breakdown of the mercaptoimino-enol intermediate of the decarboxylation reaction of the cysteine-dicarbonyl condensation product. Fisher also points out that hydrogen sulfide is forms many odiferous an hence intensely flavoured products.2 Cysteine is important as it is one of the major sources of sulfur. 

Anthocyanins usually give a purple red colour. Anthocyanins are water soluble and amphoteric. There are four major pH dependent forms, the most important being the red flavylium cation and the blue quinodial base. At pHs up to 3.8 commercial anthocyanin colours are ruby red as the pH becomes less acid the colour shifts to blue. The colour also becomes less intense and the anthocyanin becomes less stable. The usual recommendation is that anthocyanins should only be used where the pH of the product is below 4.2. As these colours would be considered for use in fruit flavoured confectionery this is not too much of a problem. Anthocyanins are sufficiently heat resistant that they do not have a problem in confectionery. Colour loss and browning would only be a problem if the product was held at elevated temperatures for a long while. Sulfur dioxide can bleach anthocyanins - the monomeric anthocyanins the most susceptible. Anthocyanins that are polymeric or condensed with other flavonoids are more resistant. The reaction with sulfur dioxide is reversible. 

Whether the flavour used is natural, nature identical, synthetic, or a mixture it has to be dosed into the product. Although some flavourings are very intense the volume added to the product has to be large enough for the equipment or the people to add it with sufficient accuracy. The flavour of course has to be uniformly distributed in the product. This normally means producing the flavour as a solution. Flavours are prepared for a particular use. As an example, citrus oil based flavours can be dissolved in various alcohols. 

The actual levels at which additives are used in foods may differ from those listed in the EU Directives since these are intended to achieve the maximum technological effect. In practice use levels might be much lower. For example, it is not always necessary to create very intense colours and the amount of colourant needed will also depend on the natural colour of the matrix. Similarly, many sweeteners are used in combinations in order to control costs whilst avoiding unpleasant side-flavours. This means that in order to gain an accurate impression... 

Intense sweeteners are characterised by a high sweetness intensity on a weight basis. Sweetness intensity values differ for general comparisons standard sweetness intensity values are often used with sucrose being the standard with a sweetness intensity of 1. Sweetness intensities depend on a number of factors, e.g. concentration and presence of flavours or taste components. They are therefore not a suitable tool for calculation of use concentrations except for very preliminary approaches. 

Other than the sweeteners discussed so far thaumatin is a polypeptide consisting of amino acids commonly found in food proteins. It is quickly and completely digested like proteins and did, after demonstration of its metabolic characteristics, only require a rather limited set of safety data. In contrast to the other intense sweeteners the ADI of thaumatin is not specified , as for substances of similar composition.27 It is approved in many countries but, owing to its flavour enhancing properties, is often used as a flavour enhancer rather than a sweetener. 

FAD. FMN AND RF CONCENTRATION (juG/L) FOR WINES. BEERS AND FRUIT JUICES AND THE ESTIMATE OF THE AVERAGE INTENSITY OF THE DEFECT SUNLIGHT FLAVOUR AFTER EXPOSURE TO LIGHT OF SAMPLES... 

FRIJTERS, J.E.R., BEUMER, S.C.C., KLARENBEEK, J.V. and JONGEBREUR, A.A. (1979) Psychophysical methodology in odour pollution research the measurement of poultry house odour detectablitv and intensity. Chem. Senses and Flavour 4 (4), 327-340... 

F.Patte, M.Etcheto, P.Laffort, Selected and Standardized Values of Suprathreshold Odor Intensities for 110 Substances, Chemical Senses and Flavour, 1, 1975, 283-305. 

Application of Sweetener Flavour Antibiotic High intensity Antibiotic... 

Partial least squares regression analysis (PLS) has been used to predict intensity of sweet odour in volatile phenols. This is a relatively new multivariate technique, which has been of particular use in the study of quantitative structure-activity relationships. In recent pharmacological and toxicological studies, PLS has been used to predict activity of molecular structures from a set of physico-chemical molecular descriptors. These techniques will aid understanding of natural flavours and the development of synthetic ones. 

The EU Regulation on food additives necessary for storage and use of flavourings, including respective conditions for their use, has been established. Following several years of intensive discussion and several drafts. Directive 2003/114/EC amending Miscellaneous Directive 95/2/EC was been published on 22 December 2003 [5, 6]. 

The most important flavour compound in raw onions is thiopropanal-S-ox-ide, the lachrymatory factor [145,146]. Other important flavour compounds are 3,4-dimethyl-2,5-dioxo-2,5-dihydrothiophene and alkyl alkane thiosulfonates such as propyl methanethiosulfonate and propyl propanethiosulfonate with a distinct odour of freshly cut onions [35, 36, 147]. Various thiosulfinates that have a sharp and pungent odour may also contribute to the flavour of onions. These compounds, however, are rapidly decomposed to a mixture of alkyl and alkenyl monosulfides, disulfides and trisulfides (Scheme 7.3) of which dipropyl disulfide, methyl ( )-propenyl disulfide, propyl ( )-propenyl disulfide, dipropyl trisulfide and methyl propyl trisulfide are the most important contributors to the aroma of raw and cooked onions (Table 7.5, Fig. 7.6) [148-150]. Recently, 3-mercapto-2-methylpentan-l-ol was identified in raw and cooked onions eliciting intense meat broth, sweaty, onion and leek-like odours [142, 151]. 

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