Oyster Sauces: Content and Comparison

by Jacqueline M. Newman

Sauces, Seasonings, and Spices

Fall Volume: 1998 Issue: 5(3) page(s): 11, 12, and 21

The Five Sauce Comparison in an earlier issue of Flavor and Fortune in Volume 5(1) on pages 16 and beyond not only fulfilled a promise, but also brought questions about other sauces that asked about content, regional use, recipes, and more. With these queries in mind, this issue investigates oyster sauce; future issues will evaluate yet others. Why oyster sauce; it was requested most since the barbecue sauce comparison. One can understand why, there is much variety in oyster sauces on the shelves of large Chinese and other Asian supermarkets. There were also many brands of this sauce in several markets on Long Island.

Reading Chinese cookbooks for relaxation, as I do almost daily, it is impressive how many authors tell their readers that one brand or another is their preferred oyster sauce. That is of particular interest because the same authors did not give advice for soy sauce or most other items. That piqued my curiosity and I began to query anyone who would discuss Chinese sauces with me. I learned that oyster sauce had a brand name favorite more often than any other Chinese ingredient. I wondered why and have no answers, do you?

Some people asked what is in oyster sauce. The ingredient information about oyster sauce in books is sometimes in conflict with ingredients on their labels. Authors T.C. Lai, Gloria Bley Miller, Nina Simonds, and Pat Tung, among others, advise that oyster sauce contains soy sauce. I found not a single label indicating that directly and many not even doing so indirectly. There are other differences besides soy sauce; some advise that oyster sauce is made from dried oysters, others say fresh oysters; some advise that the oysters, fresh or dried, are ground while others say never to grind but to chop the oysters and do so coarsely; yet others say boil the oysters whole. Some authors make oyster sauce using only water, salt, cornstarch, caramel coloring, and the oysters. Several say that oyster sauce also has other seasonings but they never mentioned which ones.

On the twelve different bottles bought for this comparison, all labels list oyster extract, water, salt, and sugar in one way or another. Some also say that they contain monosodium glutamate (MSG), soy protein in one form or another, guar gum, wheat flour, lactic acid, yeast extract, and preservatives. One can assume that several of the products have soy sauce in them because a few contain ingredients used to manufacture most soy sauces. Thin or light soy is usually made with water, soy beans, salt and flour while dark or thick soy from water, molasses (or another sugar source), salt, soy beans, and flour.

Soy sauce is ubiquitous in Chinese cooking while oyster sauce is not. It is primarily a southern condiment used for cooking and dipping. The oysters are cultivated in Hong Kong, Kwangtung, and in nearby areas, raised not only for sauce or other food usage, but also for pearls.

Oysters are a marine bivalve that like to live in brackish waters in the Pearl River delta and other bay areas. They prefer warm relatively still-water estuaries rich in organic matter. They are not always found in these types of waters and, they can not be raised everywhere.

When cultivated, oysters start as larvae called spats seeded in shallow waters. In some months, when about half-inch in size, they are moved to deeper areas. There, in about three years, they are fattened and ready for consumption.

Some say that small oysters have better flavor; this can not be judged in the United States because only oysters can only be harvested when the shell measures three or more inches.

Many who adore these sea creatures prefer them raw or lightly cooked. For me, a favorite way to preprepare fresh oysters is to water blanch them for 30 seconds then drain immediately. Though the term is to "blanch," do not dip them into cold water as one does after blanching. This thirty second hot water bath is all that is needed o plump and ready oysters for immediate use in a variety of home recipes.

In China, early records indicate oysters used dried, not fresh. During the Tang Dynasty (circa 618 - 907 CE), cooked in wine, dried oysters were very popular. More recently, they are made into oyster sauce as well as appreciated fresh, stir-fried, and deep-fried.

Lee Kum Kee makes several different commercial oyster sauces. Their brochure indicates that a restauranteur named Kum Sheung Lee founded their company in a coastal village of Nam Shui at the estuary of the Pearl River. Mr. Lee, seeing an abundance of oysters there, was inspired to pioneer a seasoning which lead to the creation of the first oyster flavored sauce. This singular reference, trade or otherwise, is the only one that mentions anything about the origins of this sauce.

I do not know how he did it then, but now bottled and canned oyster sauce is made with large quantities of raw or dried oysters; more raw than dried, manufacturers tell me. They are salted. washed, boiled in fresh water about half an hour or so, and then removed from the liquid. More oysters are added to it, they are boiled again and again until the remaining liquid is thick and brown. Years ago, the darkish liquid was put into large pottery jars and cooled, then the sauce poured into smaller containers and sealed for later use. Today, some manufacturers just add other ingredients, bottle, and seal it.

Whole oysters are drained from the above liquid, dried in the sun a few hours, then dried twice as long in the shade. When the correct texture is reached, they are coated with oil and sold. These dried oysters have a short shelf life, usually one or two weeks. To prepare dried oysters for longer storage, they need oven drying; that yields an oyster of firmer texture.

When I first learned to cook Chinese food, I watched others, learned by trial and error, and purchased products seen in the pantries of my mentors. When teaching Chinese cooking as a non-schooled instructor, students asked where I learned to cook. Some were not satisfied with my response so I enrolled in a course with Virginia Lee (who later authored The Chinese Cookbook by Craig Claiborne and Virgina Lee, Lippincott, 1972). That provided them a more acceptable answer and me more information. My class notes indicate that Mrs. Lee's said to "buy the thinnest oyster sauce, even that with a grayer color as it would have the least amount of flour or starch and the most oysters"; and to buy one "not too sweet."

Of the bottled sauces tested for this article, all were lots thicker and browner than I remembered from when taking her course and all had one or another thickener and sugar listed alone or as caramel. Be advised that the caramel is added for color and flavor and is usually made by browning sugar, the starch is purely for texture. When I repeat Mrs. Lee's advice, students wonder aloud as to how a thin sauce can have more oysters than a thicker one. I am not sure that they do, but they certainly taste better.

To do the taste testing for this article, several in-house sessions were dedicated to using groups of oyster sauces prepared either in meat or in vegetable dishes. All together, twelve different oyster sauces were tested that way using bottles purchased in large Chinese supermarkets. After those tests, the top four and two more (those most recommended in cookbooks that had not made it to the top in the in-house testing) were tested again by outside taste testers.

The twelve sauces are manufactured in four different countries. Eight are made in Hong Kong with five of these different brands made by/for Lee Kum Kee, two in China, and one each in Malaysia and in Singapore. Because they are sold in the United States, ingredients must be listed in reduced order by weight. The order varied, almost all listing water as an ingredient. Two of the labels said, 'for USA market only.'

Every one of the bottles calls itself an 'oyster flavored sauce.' Eleven of them have oyster extract, or oyster extratives, as some call them. One does not, it is a vegetarian product. Every bottle lists salt. Oysters, a rich protein food, are not in oyster sauce. The sauces only use the water extracted from cooked oyster liquid. Thus, the amount of protein in all twelve sauces is listed as and varies from none to one gram.

There are major differences in the amount of carbohydrate in these twelve sauces are reported in grams (one to twelve) and the amount of sodium in milligrams (three hundred to thirteen hundred). The number of calories varies (five to thirty) per tablespoon; and there is no fat and no cholesterol in these bottled oyster sauces.

Below, Numbers 1 though 12 indicate they are made by Kum Chun, Amoy, Panda, Vegetarian, Yu Yee, Choy Sun, Oriental Mascot, Sa Cheng, Haddon House, New Brand, Hop Sing Lung, and Premium, respectively; and the information that follows comes from their labels. In the hard copy, this information is in a table.

Amounts are given per tablespoon. Column A is the Manufacturer, as listed above. Column B tells where the product was manufactured (HK=Hong Kong; C=China; M=Malaysia; and, S=Singapore). Column C is the price paid per bottle (in US dollars and cents). Column D is calories per tablespoon and Column E is milligrams of sodium per tablespoon.

The brands in order in Column B are made in: HK, HK, HK, HK, C, HK, M, C, S, HK, HK, HK, and HK, respectively. Column C has their prices; they are: 0.89, 0.99, 1.29, 1.29, 1.49, 1.49, 1.69, 1.99, 2.69, 2.69, 2.67, and 3.79, respectively. Column D indicates calories per tablespoon and are: 15, 15, 25, 25, 10, 25, 25, 10, 10, 25, 5, and 30, respectivley. The last column has milligrams of sodium per tablespoon and are: 670, 825, 990, 770, 430, 1010, 740, 430, 300, 1040, 740, and 1300, respectively. For your information, the four, five, six, seven, eight, and nine do not contain MSG, though a few do contain other flavor enhancers. Except for the one made by Amoy (#2), all these sauces do contain sugar.

For your information, item #'s 4, 5, 6, 7, 8, and 9 do not contain MSG, though a few contain other flavor enhancers, and except for Amoy (#2), all of them contain sugar. Three use no soy or soy protein (#'s 8, 11, and 12), one uses sodium benzoate as a preservative (#1), another says "preservatives" (#11). Other ingredients include whey (# 2), lactic acid (#4), and yeast extract (# 4).

Eleven of the twelve bottles come filled with 14 to 18.7 ounces of oyster sauce, the other, item #9, has only 5.6 ounces. The five items manufactured by Lee Kum Kee have expiration dates that vary from two to four years from date of purchase. No other oyster sauce comes with a date, though many have lot or scrambled numbers that may include a hidden date.

For those who do not have access to bottled oyster sauce, and/or do not wish to purchase from a mail-order sauce, there are several ways to make oyster sauce at home. Below are two slightly different preparation techniques, try one or both of them. It is interesting to note that the results of the taste testing follow and there is no single winner. In the in-house taste testing, eight of the bottled oyster sauces used in this taste testing garnered more than one first-place vote. In alphabetical order, they are: Amoy, Choy Sun, Haddon House, New Brand, Oriental Mascot, Panda, Premium, and Vegetarian (item #'s 2, 6, 9, 10, 7, 3, 12, and 4, respectively). Of these, the four with the most votes were: Amoy, Panda, New Brand, and Premium. The above four were retested with the two sauces most frequently mentioned in cookbooks, also in alphabetical order, the Hop Sing Lung and Sa Cheng brands (#'s 11, and 8)

Some comments about those preferred by the cookbook authors but not selected by the taste testers are for the Sa Cheng brand: Almost too light, has no complexity; minimal aroma; very little taste; and thin; and for the Hop Sing Lung brand: Bland, minimal taste, salty, very little aroma, and hardly any oyster taste.

Comments about those oyster sauces with several votes include for the Amoy: Mild, nice taste, pleasant oyster after taste, and delightful flavor; and for the New Brand: Complex texture, smooth, intense flavor, slightly sweet, and a little salty aftertaste. Also, for the Panda: Not too salty, nice aroma, pleasant mild taste, a little more intense than others, both sweet and salty aftertaste; and for the Premium: Nice meaty aroma, light, good oyster taste, pleasant, a little salty after taste, and good aroma.

Though none of the taste testers selected either sauce most frequently mentioned in the cookbooks as their favorite oyster sauce, nearly half did pick one of them as their second choice. The second spots were equally divided between the two cookbook recommendations.

Of the four best, the same four most as in the in-house taste testing, three are manufactured in Hong Kong by the same manufacturer, the same address given on each of their labels. Of these four, some liked the under one dollar one as much as they liked the most expensive one costing almost four times that amount. Also, an equal number voted for an oyster sauce with eight hundred twenty-five milligrams of sodium per tablespoon as one with thirteen hundred milligrams. Liked best were ones with varied calorie amounts but with MSG.

In this taste testing, the top two are preferred equally. These are Amoy (#2) and New Brand (#10); the one just under these was Choy Sun (#6). Prior to this taste testing, I was a Premium user (#12); however, after all the testing was completed, I took the three best and made identical batches of a shrimp dish. My in-house testing and my own blind taste-testing showed me that differences were minimal. I suggest that you do your own evaluation. I might now purchase New Brand because I appreciated knowing there was less sodium; though truth be told, I barely tasted the difference. Can you?
Oyster Sauce made Two Ways
Method 1: Grind a pint of raw oysters and bring them, the liquid drained from them, and one-quarter to one half cup of water to the boil. Boil for five minutes, then reduce the heat and simmer for half an hour. Strain and discard the oysters at this point, add three tablespoons soy sauce to the remaining oyster liquid, stir, and use.
Note: This can be refrigerated for up to one week, the discarded oysters used in an omelet or another dish.
Method 2: Mix one or more pints of raw oysters and the liquid drained from them with one-half cup of chicken stock and two tablespoons of Shaoxing wine or dry sherry. Bring this mixture to the boil then simmer for ten to fifteen minutes. Then add three tablespoons of soy sauce, one teaspoon of sugar, and a teaspoon of corn oil. Stir well and simmer for another ten minutes. Cool. Then strain and discard the oysters.
Note: This can be refrigerated for up to one week, the discarded oysters used in an omelet or another dish.

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