Another sharp increase in the cost of energy pushed wholesale prices up 1.1 percent in July, ending several months of relative moderation, the government reported yesterday.

The jump followed more modest increases of 0.5 percent in June and 0.4 percent in May and brought the rise in wholesale prices for the first seven months of 1979 to 11 percent, the worst since before the 1974-75 recession.

Moreover, analysts said, the increase did not reflect any of the latest round of crude-oil price rises announced by the oil-exporters' cartel in June or the start of decontrol of domestic oil prices ordered by President Carter. Because of lags in collecting data, these will not appear until next month.

Although food prices remained steady in July for those items ready for shipment to supermarkets, prices of farm products leaped 2.1 percent, dampening White House hopes for a long-term respite in retail food prices.

Analysts both in and outside the government agreed the new figures made it less likely that retail prices would stay within the 10.6 percent increase for all of 1979 that the White House has forecast.

A revised internal administration forecast has raised that estimate to 11 percent, but high-level policymakers have not yet embraced it formally. Consumer prices this year have risen at a 13.2 percent annual rate.

The administration greeted yesterday's figures with conspicuously little comment. White House press secretary Jody Powell said only that the report "underlines our belief...that inflation is the number one problem."

Carter has called the food industry leaders to a White House meeting on Monday to try to prod them into lowering retail prices more rapidly to reflect recent declines in wholesale food prices and farm prices.

However, yesterday's report may take some of the edge off the president's appeal. Food industry leaders say prices are responding with the usual lag, but argue that they're strapped by steep increases in energy costs.

The rise in energy prices was by far the major factor behind July's speedup in wholesale prices. Producer's prices of home heating oil mumped 9 percent over the month, while gasoline prices climbed 3.9 percent.

There also were sharp increases in manufacturers' prices on a broad range of household items from appliances and jewelry to floor coverings and dinnerware. These rose 0.8 percent, up from 0.6 percent in June.

Prices of foods ready for shipment to grocery stores remained unchanged in July after plunging 1.2 percent in June and 1.3 percent in May. There were continued steep declines in meat and fresh vegetable prices.

However, prices of raw farm products jumped 2.1 percent, reversing the declines of the three previous months. Included among the increases were a 25.9 percent jump in green coffee prices and a 13.1 percent rise in grain prices.

Prices of other crude materials - also a harbinger of coming inflation trends - climbed sharply in July, rising 1.8 percent, or more than twice their pace in May and June. Again, the main culprit was energy prices.

Prices of products still in the middle stages of processing soared 1.9 percent in July following an 0.9 percent jump in June. The food portion of this index jumped 6.7 percent, mainly because of higher prices for animal feeds.

The July increase brought the pace of inflation at the wholesale level for the past three months to an annual rate of 8.2 percent. Over the past 12 months, the producers' price index has risen by 10.1 percent.

The July index stood at 215.8 percent of its 1967 level. That means it took $215.80 to buy the same goods from producers last month that sold for $100 12 years ago. CAPTION: Graph, Wholesale Price Index for Furnished Goods, The Washington Post