THE CANNED pumpkin has a metallic smell and you want to know if it is safe to eat. Whom do you call for advice?

You have resolved to improve your family's diet and you want to expert guidance, fresh meal ideas and innovatice recipes that tell how many calories per serving. Where can you get that for free?

The waiter has served the vegetable soup to you and your companion at the new restaurant in your neighborhood. After one spoonful, you notice a small, wriggly creature in the bowl. Whom do you call to report the restaurant?

In all three cases the source of help is the same -- the government.

The problem, of course, is finding which goverment agency is giving away what you need or accepting the complaints you want to lodge. Since these agencies are scattered through local, state and federal branches, this can be as frustrating as the initial problem.

But there are some general guidelines that can simplify the search.

Here is a summary of where to go for help in government:

Cooking help, food safety guidance and food preparation tips are available from the cooperative extension offices operating in each jurisdiction. Telephone numbers for each are listed below.

Food publications on nutrition, family diet, recipes, additives and other topics can be ordered from the U.S. Consumer Information Center, Department A. Pueblo, Colo. 81009. The center also has a catalog listing all current material that can be obtained either free or for $2 or less.

Sanitary conditions at restaurants and grocery stores are policed by local health departments. Some of the departments also monitor menus to make sure the restaurant serves what's on the menu.

Milk freshness and milk package dating normally is under the surveillance of special dairy boards in each state or region.

Complaints and questions about the labeling, quality and safety of canned or processed foods are handled by two federal agencies -- the Food and Drug Administration on foods other than meats and poultry and the Department of Agriculture on meats and poultry.

All of the goverment agencies have come to expect certain questions from consumers calling for help and information. "They want to know how long they can store a roast in their freezer [up to one year] -- that is one of our most common requests," said Nancy Pfafflin, a home economist in the Alexandria cooperative extension office. When Pfafflin doesn't know the answer to the less-common questions -- how to make cheese from goat's milk or how to prepare persimmons -- she researches to find the information requested.

Food safety questions that Pfafflin has had to grapple with included one about the canned pumpkin with the metallic taste. "We advised against eating it becaue when something doesn't taste good, it possibly is spoiled. And we had rather be safe than sorry."

The extension office avoids giving recipes over the telephone because there is too much chance for error, Pfafflin said. But the home economists will mail them upon request. They also have a variety of publications on food preparation, such as canning and freezing, that they furnish consumers.

But the mother lode of government food publications is in the Pueblo Consumer Information Center, which issues a catalog each quarter of its current offering. Last year the center mailed out an estimated 24 million publications on a range of consumer topics, including food. The most popular publication on food is a 64-page magazine compiled by the U.S. Department of Agriculture and entitled "Food." With a front cover depiciting a cup of split pea soup and a handful of breadsticks, the magazine looks more like a lively newsstand publication than a government brochure.

"Food" provides what its authors call as "hassle-free guide to a better diet." It is billed as the first in a new series of USDA publications intended to give readers "up-to-date, reliable information about food and nutrition issues and suggestions on how to apply this information to your food decisions." Among other things, "Food" suggest how breakfast can be a more interesting meal, how snacking can be nutritional and how meals can be planned for a household in which some members are attempting to lose weight while others are trying to gain. The magazine gives the recipes for its suggested menus and tells how many calories per average serving.

At the goverment bookstores here, "Food" is sold for $3.25 a copy. But it is free when ordered by mail from the Consumer Information Center in Pueblo. Ask for "Food 544J". At the same time, you can request the catalog of other publications, which cover a range of material including food labels, health foods, food additives, microwave ovens and brown bag lunches. Some of the publications are free; others are priced generally for $2 or less. Local government bookstores may stock some of the publications in the catalog, but because they are under a legal mandate to sell their material rather than give it away, they don't stock any of the free publications. As a result, any free booklet must be ordered from Pueblo.

Consumers who want to ask a question or file a complaint about a food problem can use the telephone in most cases. This can often -- but not necessarily aways -- produce results. To keep frustrations at a minimum, remember that it may be necessary to call more than once because the telephone number is busy and that the agency may simply record the information without offering any assurance that it will act upon your comments. Also, of course, the agency organization is subject to change, meaning that you may reach the agency only to discover that it wants to refer you to another.

But here is a list to start:

Cooperative extension offices for general help in the kitchen. District of Columbia, 727-2004; Montgomery County, 948-6744; Prince George's County, 952-3116; Fairfax County, 691-3433; Alexandria, 750-6393, and Arlington, 558-2475.

If the restaurant or retail store is dirty, if there are signs of rodents or roaches, if the food could pose a health hazard, telephone the local environmental health department in which the establishment is located. In Montgomery County, 468-4110; Prince George's County, 794-6800; District of Columbia, 724-4113; Fairfax County, 534-0343; Arlington, 558-2661, and Alexandria, 750-6672.

If the menu isn't truthful -- it says 16-ounce steak but you are served a 12-ounce steak, for example -- the complaint involving a Fairfax or Alexandria restaurant can be filed with the Virginia Office of Consumer Affairs, 573-1286. If the restaurant is in Arlington, the District, Montgomery County or Prince George's County, the complaint would go to the local health department listed above.

If you have reason to believe that a food product weighs less than the amount stated on the label or that the scales at a particular store are wrong, the complaint goes to the local weight-and-measure unit. In Montgomery County, call 279-1776; Prince George's, 952-3994; District of Columbia, 767-7923; Fairfax County, 691-2388; Arlington, 558-2142, and Alexandria, 750-6675.

If you have a complaint or question about milk that is being sold past the package sell date, speak to the store management first. If the store fails to act, contact in Maryland the Division of Milk Control, 301/383-2755; in Virginia, the state Office of Consumer Affairs, 573-1286, and in the District of Columbia, the health department, 724-4113.

If you want to apply for food stamps, call Montgomery County, 468-4394; Prince George's, 779-5970; District of Columbia, 727-0858; Alexandria, 750-5774; Fairfax County, 938-5300; Arlington, 558-2325.

If you want to report processed or canned goods -- except meat or poultry -- that are swollen or that contain foreign objects, call FDA at 443-1240. The Agriculture Department handles meat and poultry complaints and questions on 472-4485.

If you have a question or complaint about labeling of canned or processed goods, except meat or poultry, call the FDA at 443-3170. The Agriculture Department takes labeling questions about meat and poultry at 472-4485.