title_body: What should I expect from a Belgian triple (tripel)?
upvoted_answer: I expect a high alcohol beer, with a lot of complex flavors.  One that the alcohol content will "sneak" up on you because it isn't very obvious in the taste.  
  
  Quoting from the Beer Judge Criteria:
  
  
    Aroma: Complex with moderate to significant spiciness, moderate
    fruity esters and low alcohol and hop aromas. Generous spicy, peppery,
    sometimes clove-like phenols. Esters are often reminiscent of citrus
    fruits such as oranges, but may sometimes have a slight banana
    character. A low yet distinctive spicy, floral, sometimes perfumy hop
    character is usually found. Alcohols are soft, spicy and low in
    intensity. No hot alcohol or solventy aromas. The malt character is
    light. No diacetyl.
    
    Appearance: Deep yellow to deep gold in color. Good clarity.
    Effervescent. Long-lasting, creamy, rocky, white head resulting in
    characteristic “Belgian lace” on the glass as it fades.
    
    Flavor: Marriage of spicy, fruity and alcohol flavors supported by a
    soft malt character. Low to moderate phenols are peppery in character.
    Esters are reminiscent of citrus fruit such as orange or sometimes
    lemon. A low to moderate spicy hop character is usually found.
    Alcohols are soft, spicy, often a bit sweet and low in intensity.
    Bitterness is typically medium to high from a combination of hop
    bitterness and yeast-produced phenolics. Substantial carbonation and
    bitterness lends a dry finish with a moderately bitter aftertaste. No
    diacetyl.
    
    Mouthfeel: Medium-light to medium body, although lighter than the
    substantial gravity would suggest (thanks to sugar and high
    carbonation). High alcohol content adds a pleasant creaminess but
    little to no obvious warming sensation. No hot alcohol or solventy
    character. Always effervescent. Never astringent.
    
    Overall Impression: Strongly resembles a Strong Golden Ale but
    slightly darker and somewhat fuller-bodied. Usually has a more rounded
    malt flavor but should not be sweet.
    
    Comments: High in alcohol but does not taste strongly of alcohol. The
    best examples are sneaky, not obvious. High carbonation and
    attenuation helps to bring out the many flavors and to increase the
    perception of a dry finish. Most Trappist versions have at least 30
    IBUs and are very dry. Traditionally bottle-conditioned (“refermented
    in the bottle”).
    
    History: Originally popularized by the Trappist monastery at
    Westmalle.
    
    Ingredients: The light color and relatively light body for a beer of
    this strength are the result of using Pilsner malt and up to 20% white
    sugar. Noble hops or Styrian Goldings are commonly used. Belgian yeast
    strains are used – those that produce fruity esters, spicy phenolics
    and higher alcohols – often aided by slightly warmer fermentation
    temperatures. Spice additions are generally not traditional, and if
    used, should not be recognizable as such. Fairly soft water.