Sour flavours

We see how solvated protons impart the subjective impression of a sour, bitter flavour to the ethanoic acid in vinegar. In fact, not only the sour flavour, but also the majority of the properties we typically associate with an acid (see Table 6.1) can be attributed to an acidic material forming one or more solvated protons H+(aq) in solution. 

The separated buttermilk is drained. Its milk fat content should be as low as possible which is mainly influenced by the way of physical cream ripening. Sweet buttermilk contains more milk fat (0.3-0.6%) than sour buttermilk (0.2-0.3%). The butter granules are washed with cool tap water to reduce the buttermilk solids content. This step is omitted in cases where buttermilk drainage is sufficient. The process of buttermilk and wash water removal is controlled in such a way that a low residual water content (about 13%) is obtained, so that the final water content can be adjusted to 16% by controlled addition of flavour concentrates/cooking salt solution/water. Addition of sour flavour concentrates allows the... 

Sour flavours can be improved with acid flavours probably in addition with sweet flavourings. Also substances that suggest a sour taste by smell or colour (for example, lemon + yellow or raspberry -i- red) can be used. 

Sourness and bitterness are instinctively unpleasant sensations many of the toxins that occur in foods have a bitter or sour flavour. Learned behaviour will overcome the instinctive aversion, but this is a process of learning or acquiring tastes, not an innate or instinctive response. 

Sour dough bread is made all over the world in both primitive and advanced societies. In primitive societies there is no alternative, but in advanced societies sour dough bread is made for its special flavour. Sour... 

Sour dough bread has a range of flavours that are not present in other bread also it keeps relatively well. The keeping properties, no doubt, originate from some of the products of the side-reactions that have taken place in the dough. There is no need to add propionic acid as a mould inhibitor as some is likely to be present naturally. Quite possibly, some of the substances produced by the fermentation would not be permitted as additives ... 

If the culture is to provide both the yeast and the flavour of sour dough then either it must acquire a wild yeast or a starter culture that includes yeast must be added. In some cases the sour dough culture is only used to give the sour dough taste while conventional yeast is added. 

Flavour is of increasing importance when food is sufficiently abundant for consumers to exert choice. Sensory analysis, using trained laboratory panels, has been developed to profile fruit flavours, and describe relationships between products with a marked de ee of confidence but is time-consuming, requiring d icated obs ers who appreciate the nuances of individual character. Many, if not most, consumers, however, do not discriminate between fruit flavours. In dried orange juices, sweetness has been shown to be the major factor determining preference in canned juices, sourness and in frozen juices the interaction between sweetness and sourness is the significant factor (77). 

Flavourings are a major category of ingredients intentionally added to food and feeding stuff. Flavourings are concentrated preparations with the primary purpose to impart flavour except for substances that have an exclusively sweet, sour or salty taste. They are added in small amounts to food or feeding stuff but are not intended to be consumed as such. 

Key flavour Peach Nectarine P. persica Apricot Plum Sweet cherry Sour cherry... 

Key flavour compounds Peach P. persica) Nectarine P. persica var. nucipersica) Apricot P. armeniaca) Plum P. domestica) Sweet cherry P. avium) Sour cherry (P cerasus)... 

The typical flavour of sour cherries is produced during processing into wine, liqueur, juice, jam or fruit sauce. Benzaldehyde has been determined to be the most important aroma compound in sour cherries [82], but benzyl alcohol, eu-genol and vanillin are also important flavour compounds (Table 7.2, Fig. 7.5) [83]. Growing and storage conditions affect the concentration of benzaldehyde, benzyl alcohol, eugenol and vanillin [83, 84], and cold and rainy weather produces sour cherries with a less delicate sour cherry aroma [83]. 

Non-volatile flavour compounds in the sense of this chapter are defined as molecules which cause one of the sensory impressions sweet, bitter, salty, sour or umami (Fig. 23.2). 

These natural acids synthesised from natural alcohols have market prices of less than 100 per kilogram and are of great importance to the flavour industry either because of their intense smell and sour taste or as substrates for enzymatic... 

The characterisation of a fruit type or variety will be reflected in the flavour profile of its volatile components. Analytical techniques can produce an accurate peak profile using gas chromatography, but in simpler terms the sensory receptors of most individuals can quickly differentiate between fruit varieties. We have four basic taste senses, sometimes described as sweet, sour, acid and bitter, and these are identified by taste receptors situated mainly on the tongue. The key component of flavour differentiation, so-called top-notes and the like, is detected not so much by taste as by aroma in the nasal cavity. Thus, during the process of eating and drinking, the release of aroma volatiles can be identified and an assessment of their value arrived at. 

Contributes sharpness, sourness, background to flavour. Increases thirst-quenching effects... 

Note These concentrations, in water, were considered to be equivalent (tartness, sourness) from taste trials carried out in the laboratories of Borthwicks Flavours (now Danisco (UK) Ltd.), Wellingborough in 1990. Although subjective they give a proximate comparison of the pure acid effect in solution. 

Phosphoric acid has a drier, and perhaps sharper, flavour than either citric or tartaric acid, tasting rather of flat sourness , in contrast with the sharp fruitiness of citric acid. It therefore appears to blend better with most non-fruit drinks. 

The wine is tasted to ascertain if it is sweet or dry, and if there is any abnormality of taste indicative of alteration or adulteration. Thus, the alcoholic taste may not harmonise with the quality of the wine, or there may be acidity caused by souring of the wine, harshness due to tannin, a flavour from the lees or cask or from carbon dioxide, abnormal sweetness, a taste of sulphur dioxide, etc. 

The flavour threshold for acetic acid depends on wine type and style, and ranges from 0.4 to 1.1 g/L (Dubois 1994). At threshold concentration it provides warmth to the palate and, as the concentration increases, it imparts a sourness/sharpness to the palate and a vinegary odour at higher concentration. As the fatty chain length increases, volatility decreases and the odour changes from sour to rancid and cheese (Francis and Newton 2005). Sensory studies show that hexanoic, octanoic, and decanoic acids can contribute to the aroma of some white wines (Smyth et al. 2005). The branched-chain fatty acids can also contribute to the fermentation bouquet of wine, with the concentration of 2-methylpropanoic acid typically exceeding its odour threshold (Francis and Newton 2005). 

OXYTRIPYLLUM — The Sour or Acid Trefoil so called, firstly, on account of its flavour, and, secondly, because it has three leaflets like common trefoil. 

Sugar confectionery (strawberry on top in all regions) and regions with very specific flavours and generally a high geographic diversity (chocolate within the top ten of Asia, liquorice (Europe), tamarind (Latin America), sour (North America)). 

For other product classes, it is characteristic that the flavour only forms or is changed significantly during production. Thermal, enzymatic and microbiological processes can be responsible for these changes. Examples are the ripening of salami and sour dough fermentation. In both cases, undesired bacteria can cause off-flavour formation. 

The latter plays an important role with freeze-dried sour dough. The microorganisms cultivated on flour substrate already form a number of flavour constituents, which stick well to the flour matrix. The subsequent freeze drying preserves both, flavour and microorganisms. The resulting product saves time in the bakery and improves the quality of bread. 

Other flavour modifiers Miraculin Sour tasting substances are perceived as sweet tasting for approx, two hours... 

Last but not least, it must be mentioned that sodium chloride (often referred to as the poor man s flavour enhancer ) has a flavour enhancing effect at usage levels below and above its taste threshold (370 to 5000 ppm). Without salt, many foods (both sweet and savoury) have a flat taste. Salt may enhance sweemess and mouthfeel and decrease bitter, sour and metallic sensations [4, 32]. Even in sweet foods such as cakes, candies and toffees, salt has its place. However, its presence is most critical for... 

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