Some people have allergies or sensitivities to foods which are not problematic to most people. This occurs when a person's immune system mistakes a certain food protein for a harmful foreign agent and attacks it. About 2% of adults and 8% of children have a food allergy. The amount of the food substance required to provoke a reaction in a particularly susceptible individual can be quite small. In some instances, traces of food in the air, too minute to be perceived through smell, have been known to provoke lethal reactions in extremely sensitive individuals. Common food allergens are gluten, corn, shellfish (mollusks), peanuts, and soy. Allergens frequently produce symptoms such as diarrhea, rashes, bloating, vomiting, and regurgitation. The digestive complaints usually develop within half an hour of ingesting the allergen.
Texture plays a crucial role in the enjoyment of eating foods. Contrasts in textures, such as something crunchy in an otherwise smooth dish, may increase the appeal of eating it. Common examples include adding granola to yogurt, adding croutons to a salad or soup, and toasting bread to enhance its crunchiness for a smooth topping, such as jam or butter.
The ideal temperature for serving a particular wine is a matter of debate by wine enthusiasts and sommeliers, but some broad guidelines have emerged that will generally enhance the experience of tasting certain common wines. A white wine should foster a sense of coolness, achieved by serving at "cellar temperature" (13 °C (55 °F)). Light red wines drunk young should also be brought to the table at this temperature, where they will quickly rise a few degrees. Red wines are generally perceived best when served chambré ("at room temperature"). However, this does not mean the temperature of the dining room—often around 21 °C (70 °F)—but rather the coolest room in the house and, therefore, always slightly cooler than the dining room itself. Pinot noir should be brought to the table for serving at 16 °C (61 °F) and will reach its full bouquet at 18 °C (64 °F). Cabernet Sauvignon, zinfandel, and Rhone varieties should be served at 18 °C (64 °F) and allowed to warm on the table to 21 °C (70 °F) for best aroma.
During aeration, a younger wine's exposure to air often "relaxes" the drink, making it smoother and better integrated in aroma, texture, and flavor. Older wines generally fade (lose their character and flavor intensity) with extended aeration. Despite these general rules, breathing does not necessarily benefit all wines. Wine may be tasted as soon as the bottle is opened to determine how long it should be aerated, if at all.[better source needed] When tasting wine, individual flavors may also be detected, due to the complex mix of organic molecules (e.g. esters and terpenes) that grape juice and wine can contain. Experienced tasters can distinguish between flavors characteristic of a specific grape and flavors that result from other factors in wine-making. Typical intentional flavor elements in wine—chocolate, vanilla, or coffee—are those imparted by aging in oak casks rather than the grape itself.
The earliest archaeological and archaeobotanical evidence for grape wine and viniculture, dating to 6000–5800 BC was found on the territory of modern Georgia. Both archaeological and genetic evidence suggest that the earliest production of wine elsewhere was relatively later, likely having taken place in the Southern Caucasus (which encompasses Armenia, Georgia and Azerbaijan), or the West Asian region between Eastern Turkey, and northern Iran.
Cooking requires applying heat to a food which usually, though not always, chemically changes the molecules, thus changing its flavor, texture, appearance, and nutritional properties. Cooking certain proteins, such as egg whites, meats, and fish, denatures the protein, causing it to firm. There is archaeological evidence of roasted foodstuffs at Homo erectus campsites dating from 420,000 years ago. Boiling as a means of cooking requires a container, and has been practiced at least since the 10th millennium BC with the introduction of pottery.
Freeze-drying requires the use of heavy machinery and is not something that most campers are able to do on their own. Freeze-dried ingredients are often considered superior to dehydrated ingredients however, because they rehydrate at camp faster and retain more flavor than their dehydrated counterparts. Freeze-dried ingredients take so little time to rehydrate that they can often be eaten without cooking them first and have a texture similar to a crunchy chip.
Population studies exhibit a J-curve correlation between wine consumption and rates of heart disease: heavy drinkers have an elevated rate, while people who drink small amount (up to 20 g of alcohol per day, approximately 200 ml (7 imp fl oz; 7 US fl oz) of 12.7% ABV wine) have a lower rate than non-drinkers. Studies have also found that moderate consumption of other alcoholic drinks is correlated with decreased mortality from cardiovascular causes, although the association is stronger for wine. Additionally, some studies have found a greater correlation of health benefits with red than white wine, though other studies have found no difference. Red wine contains more polyphenols than white wine, and these could be protective against cardiovascular disease.