【Adulterate】 , 【sophisticate】 , 【load】 , 【weight】 and 【doctor】 mean to alter fraudulently especially for profit.

【Adulterate】 , the usual and technical term, especially when used with reference to foodstuffs and drugs, implies either the admixture of ingredients of similar appearance to increase the bulk or of a harmful substance as a preservative or as a restorer or improver of appearance.

• 【adulterate】 maple syrup with beet-sugar syrup
• lime juice adulterated with five percent sulfuric acid, jellies with formaldehyde, peas with copper
  —Heiser

In its extended use 【adulterate】 implies spuriousness or loss of purity; such implications come out strongly in unadulterated, which is the equivalent of pure and sheer in their hyperbolic senses.

• that book is unadulterated trash

In meaning 【sophisticate】 is essentially identical with 【adulterate】 but its use is restricted almost entirely to raw drug and essential oil trade.

• rose oil is sophisticated with geraniol
  —Shreve

【Load】 implies the admixture of something to add 【weight】 whether as an adulterant or in the normal course of manufacture.

• numerous adulterants have been used to 【load】 tea to increase its 【weight】
  —Ukers
• most kinds of paper are loaded in some way or other . . . . The process . . . was first practiced . . . to save pulp . . . but it was found that restricted quantities of loadings improved the paper
  —Jennett

【Weight】 is used interchangeably with 【load】 but is applied more especially to textiles.

• silk weighted with salts of tin

【Doctor】 implies tampering sometimes by adulteration but more often by alterations or falsifications which give an illusion of genuineness, of superior quality, or of great value.

• doctoring poor wine with essences and brandy
• doctored his accounts to hide his thefts