Have you ever smoked a cigar you know is good, and it just tastes "off"? Usually we just blame the cigar maker, tobacconist, or our humidor, but, maybe it wasn't the cigar. It is very likely that our mouth can be "off".  The balance between Acidity and Alkalinity affects our lives in innumerable ways; from the environment, soil, and our bodies, to the food we eat and the liquids we drink.  "pH" is a measure of Acidity and Alkalinity [of a solution] on a scale where 7 is neutral; lower numbers are more Acid (down to 0), and higher numbers are more Alkaline (up to 14).

We learn in Tobacco and Taste Colleges that cigars are more Alkaline and cigarettes are more Acidic: this effects the consumption method (i.e. inhaling for cigarettes), nicotine absorption, and therefore the addictive differences between the two.

As it pertains to luxury tobacco, pH monitoring is critical for the soil and even the water used for irrigation and fermentations.  But, the greatest impact of pH does not necessarily come from the product (cigar or pipe tobacco), but rather from your mouth.  Your palate's (tongue, mouth, saliva) neutral pH setting is around 7.  Lemon juice is around 2, tomatoes are around 4, and milk is around 6.5.  Anything we consume will effect the pH level in our mouth, and subsequently, the way we perceive the taste of a cigar or pipe tobacco.

Fortunately, our mouths/palates have the ability to restore their neutrality within a short period of time. You can expedite this process by drinking water, milk, or eating plain bread, to bring your mouth closer to neutral.  If you just finished smoking a cigar and want another, you can eat a little lemon sorbet to restore some Acidity to your palate. Ultimately, maybe you like the contrasting Acidity of coffee with the Alkalinity of a cigar; if so, great - it's up to you and your personal taste. But it is good to know the facts and be aware of how our senses can be biased.