Pumpernickel bread that came to be known as "Pumpernickel", Westphalian pumpernickel is distinguished by use of coarse rye meal and a very long baking period, which gives the bread its characteristic dark color. Like most traditional all-rye breads, pumpernickel is traditionally made with an acidic sourdough starter, which preserves dough structure by counteracting highly active rye amylases. That method is sometimes augmented or replaced in commercial baking by adding citric acid or lactic acid along with commercial yeast. Traditional German pumpernickel contains no coloring agents, instead relying on the Maillard reaction to produce its characteristic deep brown color, sweet, dark chocolate,
What Is Life a combination that became the top-selling single of 1971 in that country. "What Is Life" is one of Harrison's most commercial and popular songs – a "spiritual guitar quest" that "became [a] classic", according to "Rolling Stone" magazine. On release, "Billboard" magazine's reviewer wrote of "What Is Life" and "Apple Scruffs" as "intriguing rhythm follows-ups" to Harrison's previous single, which were "sure to repeat that success" and "should prove big juke box items". In their "Solo Beatles Compendium", authors Chip Madinger and Mark Easter refer to it as an "intensely catchy track" and view its pairing with "My Sweet Lord"