Vegetable roasting

Chestnut Castanea sativa Fagaceae Cooked as a vegetable, roasted, or milled into a flour and used in soups and bread doughs... 

Coffee substitutes, which include roasted chicory, chick peas, cereal, fmit, and vegetable products, have been used in all coffee consuming countries. Although consumers in some locations prefer the noncoffee beverages, they are generally used as lower cost beverage sources. Additionally, it is not unusual for consumers in some of the coffee producing countries to blend coffee with noncoffee materials. 

Cucumbers, zucchini, and summer squashes are eaten young and picked regularly to maintain the supply. They tend to have a mild flavor. Melons are picked when ripe, and pumpkins and winter squashes are left to mature on the plant, to develop a tough skin for storage (see also p.271). Some are bland and watery while others develop sweet, rich, densely textured flesh—excellent as a roasted vegetable and for soups and stews. 

Amino acids may also undergo thermal degradation, which is almost always coupled with some other food components, particular sugars. The major types of volatile compounds formed from amino-sugar interactions include Strecker degradation aldehydes, alkyl pyrazines, alkyl thiazolines and thiazoles and other heterocycles [35, 36]. As the subject has mainly relevance for baked and roasted vegetable food products, this subject will not be discussed in further detail. 

Oxazoles have been found in relatively few cooked foods, although over 30 have been reported in coffee and cocoa, and 9 in cooked meat. Oxazolines have been found in cooked meat and roast peanuts, but not to any extent in other foods. 2,4,5-Trimethyl-3-oxazoline has been regularly detected in cooked meat [26], and when it was first identified in boiled beef [27] it was thought that the compound possessed the characteristic meat aroma however, on synthesis it was shown to have a woody, musty, green flavour with a threshold value of 1 mg/kg [28]. Other 3-oxazolines have nutty, sweet or vegetable-like aromas and the oxazoles also appear to be green and vegetable-like [28]. The contribution of these compounds to the overall aroma of heated foods is probably not as important as the closely related thiazoles and thiazolines. 

Meat products, e.g. beef, chicken, pork, lamb Vegetables, e.g. onions, potatoes, garlic Roasted products, e.g. coffee, cocoa, roasted nuts, popcorn Cereal products, e.g. biscuits, bread, extrudates Beverages, e.g. beer, wine, whiskey... 

As for S-containing heterocycles, many N-containing heterocycles are also found in heat-treated foods as secondary flavours as a result of Maillard-type reactions between reducing sugars and amino acids. Pyrazines are N-heterocycles important contributors to the taste and aroma of roasted and toasted foods as well as vegetables and fermented foodstuffs. In cultures of Pseudomonas perolens ATCC 10757, amino acids such as valine, glycine and methionine were shown to... 

F Nutty, roasted, meaty O Hazelnut, steak, meat, liver, green vegetables, "Buccu" leaf and black currant F Nuts, meat, steak... 

T at 2 ppm Sweet, roasted meat-like, roasted nut-like, chocolate-like, vegetable green-like, hydrolyzed vegetable protein-like. 

The third path to aromas are non-enzymat1c processes resulting from thermal treatment such as cooking and roasting. These reactions typically Include thermal decomposition of I1p1d, carbohydrates and proteins, and are responsible for the aroma of foods such as coffee, meat, nuts, cereals, and also contribute to the aromas of heat processed foods and vegetables. 

The aroma precursors have been selected by taking into account the significant role of the Maillard reaction. Indeed, most aroma compounds of this type are formed by the reaction of amino acids with sugars or their degradation products. So we have obtained roast beef, roast mutton and heated vegetable aromas after having treated a mixture of amino acids and glucose at different temperatures and for varied times. 

Peptides have long been recognized as important flavor compounds in processed foods. The taste of peptides per se is veil known in cheeses (1), meat (2), hydrolyzed vegetable protein including soy products T3), cocoa (A, 5) and to a lesser extent in roasted malt (6), corn steep liquor (7) and aged sake (8). Structurally, food peptides can occur as linear protein fragments (1-3, 5), cyclic dimers (diketopiperazines, DKPs)(A, 6-81 and cyclic trimers (7). 

Cashew kernels possess pleasant taste and flavor and are eaten either raw or roasted with salt. The raw nuts, which are packed in flexible packages, are usually marketed as plain cashews. The roasted nuts are usually fried in vegetable oil to light brown colour, salted and packed in cans. The flavor characteristics of plain cashew nuts are enhanced as a result of oil roasting. A literature review revealed that the flavor constituents of plain or roasted cashew nuts have not been investigated previously. In the present study, the authors have attempted to isolate the flavor compounds by steam distillation and extraction and to identify them by GC and GC-MS techniques. Thirty six compounds have been identified for the first time. 

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