Aromatic alcohols of pH 1 turned emulsive essentially (7)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

PH + ONE (the number 1) reversed (returned) + LS ( central letters o f [essentially] EMU LS IVE) – a liquid classified pH1 is an acid; PHENOLS vare acids although they will have a higher pH1 number as they are described as weak acids.