FARM BILL conferees have been busy over the last two weeks stitching new supports into the multi-billion dollar safety net for food producers, while undermining protection for the most vulnerable of food consumers.

Thus far House and Senate conferees have undone much of the good work done in their respective chambers to curb the cost of farm subsidy programs and eliminate their most objectionable features. Senate conferees compromised their attempt to reduce dairy price supports while House conferees agreed to restore expensive props for sugar and peanut farmers. The conferees then adopted a set of loan guarantees and direct payments to protect farmers against such other vicissitudes of the marketplace as grain elevator bankruptcies, personal financial emergencies and agricultural embargoes.

These concessions will cost the consumer dearly while putting the farm bill far outside the budget limit sought by the administration. The main beneficiaries of this generosity will not be the much-invoked small farmer but large corporate farms. A new Agriculture Department study shows that the largest 10 percent of farms receive almost half of all support payments.

The conferees are not without concern for frugality. They simply prefer to make their savings in less well-protected quarters. Food stamp recipients, for example, will be called upon to absorb another $700 million in losses this year--on top of the $1.65 billion in cuts voted last summer. The conferees decided to save this money by delaying for another six months a cost-of-living adjustment for food stamps (a delay of three months was voted earlier).

The cost-of-living delay cannot be defended--as could similar delays in Social Security or federal pensions--on the grounds that food stamps have been overindexed. The basic food stamp benefit is adjusted only for increases in food prices and is not affected by the CPI's inflated measure of housing costs. Nor has the food stamp program been afflicted by the benefit formula error that has further escalated Social Security costs. The food stamp delay is a benefit cut-- mean and simple--for some of the nation's poorest people.

With the administration planning still larger food stamp cuts, the chances of reversing the conferees' action are slim. One improvement, however, could be made at minor cost. Since Social Security and Supplemental Security Income payments to the aged and disabled are indexed for inflation in July --while food stamps will not be so adjusted until October--many recipients of both will have their food stamp benefits cut in July and then restored three months later. This will cause enormous confusion for both state administrators and recipients. Allowing states to skip the July food stamp reductions for the aged and disabled would be an efficient and humane addition to a farm bill that has acquired a substantial and unsavory tilt in the direction of well-heeled special interests.