Aroma development

During the oxidation process, leaf color changes from green to copper and a pleasant characteristic aroma develops. In most instances, the proper termination point is deterrnined by the skill of the process supervisor (tea maker) on whose judgment the value of the final product is highly dependent. However, some attempts to control a suitable end point by instmmental techniques have been made. The fermentation step is terrninated by firing (drying). 

Gillat, P. (2001). Flavour and aroma development in frying and fried food. In "Frying Improving Quality" (J. B. Rossell, ed.), pp. 266-366. CRC Press Inc., Boca Raton, FL. 

The early scientific discoveries relating to heat induced aroma development can be traced to the work of Louis—Camille Maillard at the University of Nancy during the period of 1912 to 1936 (2). He published at least 8 papers on the subject of the reaction of sugars with amino acids. The Maillard Reaction, or so-called, non enzymatic browning reaction chemistry, has become the focus on a great amount of scientific work (3). 

Aroma Development in Chinese Fried Pork Bundle... 

Aromas Developed by the Reactions of Carbonyl Compounds and Various Amino Compounds at 100°C ... 

Aromas Developed by Heating Glucose with Various Amino Acids... 

The data in Table VI indicate that the aromas developed when sugars and amino acids were heating at 120 and 180°C, were quite different from those produced at 100°C. Noticeable differences exist between aroma notes developed at 120°C and 180°C, this may be attributed to sugar degradation notes which become noticeable in the system heated at 135 C and above. 

Late picked apples show an Immediate aroma development and reach a considerable higher maximum compared to early picked apples. From this picture one can conclude that for optimum apple quality the picking date should be related to the consumption period. 

Figure 6. Aroma development after removal from ventilated controlled atmosphere. Influence of storage time and picking date.

Aroma development In ripening apples is dependent on a number of external and Internal factors. Dynamic headspace sampling of the volatiles from intact fruits, followed by high resolution gas chromatography or g.c.-m.s. anlysis is a convenient procedure for the study of these factors. 

Recent studies on salmon flavors revealed that a single compound appears to be responsible for the characterizing cooked salmon flavor (39). The cooked salmon flavor compound was found to have an extremely low threshold, and was Initially detected only by odor assessment of a fraction eluting at Ig of 9.6-9.7 on a Carbowax 20M packed column when headspace volatiles were analyzed from canned salmon meat. Accelerated oxidation of salmon oil did not yield salmon-llke aromas before the development of fishy oxidized aromas. However, when salmon oil was coated onto Cellte supports, and allowed to oxidize at room temperature, a distinct salmon-loaf-llke aroma developed within 24 h after Initiation of oxidation. A variety of supports were evaluated In model systems with salmon oil for their ability to produce the salmon aroma compound. Odor assessments of the oxidizing systems Table II Indicated that a range of odors developed from salmon-loaf-llke to oxidized fishy aromas, and only the Cellte system provided the aroma. 

However, when the carotenoids and acylglycerols were recombined, the salmon aroma developed. Combinations of alternate sources of fish acylglycerols along with crayfish carotenoids revealed that the necessary component for salmon flavor development was the presence of carotenoids specifically derived from salmon oil (Table III). Such results strongly suggest that the compound Is derived by co-oxldatlon of fish acylglycerols with salmon carotenoids, and that the precursor Is located In the carotenoid fraction. 

The enterococci contribute to the ripening and aroma development of cheese due to their proteolytic and esterolytic activities, as well as their diacetyl production by citrate metabolism (Centeno et al. 1999). The presence and growth of enterococci in cheeses and sausages results in organoleptically unique products, which contribute to the local cuisine and the region s heritage. Due to interlinked European and worldwide markets, these cheeses are widely distributed and are internationally considered as delicacies (Franz et al. 1999). 

Aroma development Aroma loss Porosity Shrinkage... 

Up to the desired limit in pursuit of maximum aroma development as both under and over fermentation result in deteriorated quality of black tea affecting the flavour index [44], Out of the two detectable parameters (colour and aroma), aroma is very important since a strong and unique fragrance emanates from the leaves once leaves are optimally fermented. 

Aroma development from non-floral grape precursors by wine lactic acid bacteria. Food Research International, Vol.42, No. 7, (August 2009), pp.773-781, ISSN 0963-9969... 

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