Wineries Unlimited brought its trade show, the largest

exhibit of the wines of eastern America, to Washington's back door last month. Crystal City and midweek not being a convenient combination for most of

us, the attendance must have disappointed the organizers. The point in forsaking Lancaster, Pa., the show's home for the past six years, was to bring the wines closer to a large audience. Anyway, for those who did attend, it was the best chance yet to taste the products of the steadily expanding eastern wine industry.

Since the show was on our doorstep, I was pleased to see how well the wines of our own states compared with those of further north and west. Virginia, Maryland and southern Pennsylvania, unilaterally annexed to back my argument, are keeping apace in the development of new wineries and better wines. I had tasted the wines of 20 eastern wineries at a mini- show in a Washington wine shop a couple of weeks earlier and have combined my notes from the two events for this column.

I admit to preferring eastern whites to eastern reds. In hybrids, the crossing of European vinifera and native eastern American grape varieties, the whites are, well, less native than the reds. And in vinifera, so far the whites have been more successful than the reds.

Glenora and Chateau Esperanza, both in New York's Finger Lakes region, produce enjoyable whites. Glenora's '81 Ravat Blanc, $6, fresh and dry, and Ch. Esperanza's '81 Ravat, $7.50, a germanic style late harvest, show the possibilities for ravat, a newer hybrid. Closer to home, Montbray, of Westminster, Md., has bottled the '80 Seyve-Villard in two different styles. Lot 3, $4, is the lighter, crisper and less complex. Lot 7, $6, has been wood-aged. Both are good.

Allegro, in Brogue, Pa., already known for its cabernet sauvignon, changed the style of its chardonnay from a full, oaky style in '80 to a medium-bodied, fruitier wine in '81, with good results. When released, it should be about $10.

Maryland's Byrd Vineyards poses a dilemma. Just when the wines are getting better and better, they are becoming harder to find. And even at the winery near Myersville, there is another deterrent: price. A $10 sauvignon blanc and $15 chardonnay are expensive wines, even by the standards of proven California producers.

In sweeter whites, Tabor Hill of Michigan has a delicious '81 Seyval Blanc Dry Berry Harvest, and--a surprise here--Great Western, New York, has two remarkably good ice wines. For a giveaway $6 a half-bottle, the '81 Catawba and '81 Vidal taught me a lesson on keeping an open mind--both on eastern wines and on the products of larger companies.

Great Western, part of Coca-Cola's Wine Spectrum, has remodeled its range. From Naturel Champagne, which has no more than a hint of labrusca in the latest bottling, to the still wines, which have new labels and new varietals, there is altogether a new image. We're still waiting for the still wines to be released here. Let's hope the ice wines won't be far behind.

As for reds, Wineries Unlimited and the mini-show confirmed that our mid-Atlantic states can do as good a job as any of the eastern states. That may be faint praise, however. I did like the '80 Cabernet Sauvignon, $11, from Allegro, a wine that needs at least two years more bottle age. A barrel sample of the '81 cabernet, without the final blending of a small amount of merlot, promised an even fuller-bodied wine.