* Raw sugar has largest one-session gain since Jan. 6
* Brazil real rallies to highest level in a week
* Capital flows into commodities on 1st day of quarter (Adds trade comment, updates with closing prices, adds byline, NEW YORK dateline)
By Luc Cohen and David Brough
NEW YORK/LONDON, April 1 (Reuters) - Raw sugar futures saw their largest single-session gain in nearly two months on Wednesday as the real currency of top-grower Brazil rallied and speculator money poured into underperforming commodities on the first day of the new quarter.
Cocoa on ICE Futures U.S. gained, also benefiting from the capital inflows, while arabica coffee futures rallied on the firmer real before paring gains late in the session.
"There's new money coming into the markets for the second quarter," said Nick Gentile, managing partner at commodity trading advisor NickJen Capital in New York.
"A lot of people have been running short commodities and they're getting blown out today."
Front-month raw sugar benefited from the inflows, gaining 0.39 cent, or 3.3 percent, to settle at 12.32 cents a lb in heavy volume. That was its largest single-session gain since Jan. 6.
The gains came as Brazil's real rallied to its highest levels in a week against the dollar, discouraging producer selling by reducing local returns for greenback-traded commodities like sugar.
The gains in the real prompted speculators to cover short sugar positions and could have attracted some new buying, Gentile said.
May white sugar gained $2.70, or 0.8 percent, to settle at $358.10 a tonne.
Strong demand has helped to boost the white sugar premium by 50 percent since early February, increasing the profitability of refiners and potentially boosting demand for raw sugar.
New York May cocoa gained $49, or 1.8 percent, to settle at $2,748 a tonne, also in heavy volume benefiting from fund inflows, and as investors rolled short positions out of the front-month, Gentile said.
London May cocoa gained 19 pounds, or 1 percent, to settle at 1,920 pounds a tonne.
May arabica coffee gained 1.95 cents, or 1.5 percent, to settle at $1.3485 a lb in choppy, high-volume trade, after rising as high as $1.3980.
The initial gains came as a result of the rally in top grower Brazil's real, traders said, though coffee sold off sharply ahead of the close of the trading session after hitting resistance at a key technical level.
"Maybe it should have held up better given the strengthening of the real but the chart is not healthy yet," one trader said.
May robusta coffee rose $21, or 1.2 percent, to settle at $1,750 a tonne. (Editing by Bernadette Baum)