Potato flavour

Taylor, M. A., McDougall, G. J., Stewart, D. (2007). Potato Flavour and Texture. In D. Vreugdenhil (Ed.), Potato Biology and Biotechnology Advances and Perspectives (pp. 525-540). Elsevier, Oxford. 

Table 7.8 Key flavour compounds in Fabaceae (pea) and Solanaceae (potato, tomato) vegetables... 

Methionine can be obtained from enzymatic protein hydrolysates or from petrochemical sources. To a lesser extent than cysteine, it is a raw material in Maillard reactions for the preparation of process flavours and it can also be utilised as a precursor for the chemical preparation of the sulfide methional, which is an important flavour constituent for potato, malt, seafood and many other flavours. Methional can be reduced to methionol, which can be esterified with organic acids to, for instance, methionyl acetate and methionyl butyrate, which are useful compounds for pineapple and other fruit flavours (Scheme 13.16). 

The oleoresin of parsley provides a flavour characteristic of the entire plant, and is used in chicken- and potato-soup bases, salad dressings, meatball seasonings, etc. Extraction by CO2 of Austrian parsley seed yields about 15% with extraction conditions of 450 bar and 65°C. 

Polyphenol oxidase Mushroom, grape, pear, kiwi, sago, tea, potato, strawberry, olive, beet, cocoa Enzymatic browning (pig-ments),ripening of fruits, flavour formation, colour e.g. strawberries) formation... 

Peroxidase Horse radish, apple, bean, grape, barley, potato, cucumber, pea, peanut, tomato Ripening of foods, several functions in plants, colour formation (off-) flavour formation. 

CIC the typical sulphurous flavour is represented by the high concentration of dimethyl sulphide, combined with traces of 1,2-dithia-cyclo-pentene. The vegetable-green note results from 2-isopropyl-3-methoxy pyrazine, resembling raw potatoes, and 2-sec-butyl-3-methoxy pyrazine, a green bell pepper note. 

This staple food is never eaten in the raw state the earthy taste is not quite appealing and the starch has to be transformed into an eatable form either by cooking or by baking/frying. Boiled, cooked potatoes develop a characteristic bland balanced creamy, sweet, sulphurous, earthy flavour. Fried potatoes are appreciated for their... 

CIC the earthy odour of fresh potatoes is represented by 2-isopropyl-3-methoxy pyrazine. This earthy note is supported by the mushroom character of l-octen-3-ol. The key component of boiled potatoes is 3-(methylthio)-propanal, balanced with dimethyl sulphide. The high reaction temperatures in baked and fried potatoes start the Maillard reaction to form mainly heterocyclic components 2-ethyl-3,5-dimethyl pyrazine, 2-ethyl-6-vinyl pyrazine, 5-methyl-6,7-dihydro-(5H)cyclopenta-pyrazine, 2-acetyl-l,4,5,6-tetrahydro-pyridine are responsible for the roasted, nutty cracker-like flavour. The heat-induced degradation of the potato lipids and the frying oil imparts a fatty, tallowy character to the french fried potatoes. (E,E)-2,4-Decadienal, 2-octenal, octanoic acid and decanoic acid are main contributors to this fatty note. 

Different starches show varying flavour binding capacity. Starches with a low amy-lose content (e.g. tapioca at 17%) and waxy starches consisting only of amylopectin have only a weak binding capability those with a high amylose content (like potato or maize) have a greater one. Gelatinized potato starch has been researched best. 

The binding of volatile flavouring substances to dry and air-equilibrated potato starch (which has an 8.2% water content) has also been studied [6,11 [. As one would expect, the moist starch binds more flavour than the dry one. Some of the bound substances are not even released in a vacuum at ambient temperatures and above when water is added, however, the bond is destroyed. 

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. 

Wyler, R. and Solms, J. Inclusion Complexes of Potato Starch with Flavour Compounds. In Flavour 81 (Schreier, R, ed.)., Berlin, Walter de Gruyter, pp. 693-699 (1981)... 

Alcohol is an important food ingredient that is often used as a carrier for various flavourings and for the production of vinegar. In general grape products and related products must be produced completely by Jews in order to be acceptable as kosher. Once these are heated (e.g. pasteurised), however, or alcohol coming from other sources (i.e. potatoes) may be handled or manufactured by non-Jews. 

Deck R.E. and Chang S.S. (1965) Identification of 2,5-dimethylpyrazine in the volatile flavour compounds of potato chips. Chem. Ind. (London) 1343-A. 

Nursten H.E. and Sheen M.R. (1974) Volatile flavour components of cooked potato. J. Sci. Food Agric. 25, 643-63. 

Four of the 12 flavouring agents in this current group (Nos 1771,1772,1774 and 1777) have been reported to occur naturally in foods. They have been detected in white wine, spinach, potatoes, sweet potatoes, yams, kale, brown rice, brown rice germ, brown rice sprouts, barley, barley sprouts, beans, bean sprouts, corn, oatmeal, squash, carrot, onion, chestnut, apple, shiitake mushrooms, green laver, lactobacilli and broccoli (Cutillo et al., 2003 Oh et al., 2003 Anon., 2004). No quantitative data on the natural levels in food were available, and therefore consumption ratios (the ratios of their consumption from natural food sources to their use as flavouring agents) were not calculated. 

The experiment could be extended by carrying out these investigations e How does the variety of potato affect the flavour of the chip ... 

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