CAVIAR: ROE PROCESSING MANUAL

FOREWORD

1.0 CAVIAR PRODUCTS
1.1 INTRODUCTION
1.2 THE WORD 'CAVIAR'
1.3 LABELLING PRODUCTS
1.4 CANADIAN ROE RESOURCES
2.0 ROE
2.1 OVARIES
2.2 MATURITY
2.3 YIELD
2.4 FROZEN ROE
2.5 GRADING FRESHNESS
2.6 CHEMICAL COMPOSITION
2.7 EGG STRUCTURE
3.0 SCREENING
3.1 SCREENING OPERATION
3.2 SCREENING TECHNIQUE
3.3 SCREENING DEVICES
3.4 MECHANIZED SCREENING
4.0 SALTING
4.1 PRESERVATIVE ACTION
4.2 THE SALTING MECHANISM
4.3 SALINITY
4.5 CURING EFFECT
4.6 SALTING TIME
4.7 SALINITY MEASUREMENTS
4.8 DRAINING, EGG VISCOSITY AND VISCOSITY MEASUREMENTS
5.0 PACKING
5.1 FREEZING AND REFRIGERATION
5.2 BULK AND RETAIL PACKAGE
5.3 PACKAGE TYPE
5.4 CHEMICAL PRESERVATION
5.5 ADDITIVES AND DYES
5.6 PASTEURIZATION
5.7 PACKAGING OVERVIEW
6.0 QUALITY AND SHELF-LIFE
6.1 QUALITY GRADING
6.2 ORGANOLEPTIC TRIALS
6.3 DEFECTS
6.4 CHEMICAL AND BACTERIOLOGICAL EXAMINATIONS
6.5 SHELF-LIFE
6.6 QUALITY CONTROL AND ASSURANCE
7.0 THE CAVIAR SHOP
7.1 LAYOUT AND MECHANIZATION
7.2 PLANNING A SALMON CAVIAR OPERATION
7.3 WATER QUALITY
7.4 SALT QUALITY
7.5 BRINE PROPERTIES
7.6 BRINE MAKING REQUIREMENTS AND APPARATUS
7.7 SALTING TANKS
7.8 MISCELLANEOUS TOOLS, INSTRUMENTS AND MECHANISMS
7.9 SANITATION
8.0 PROCESSING DIFFERENT SPECIES
8.1 HARVESTING LUMPFISH ROE
8.2 PROCESSING LUMPFISH CAVIAR
8.3 WHITEFISH AND OTHER ORDINARY FISH
8.4 STURGEON FISHERIES
8.5 PROCESSING STURGEON CAVIAR
8.6 SALMON FISHERIES
8.7 PROCESSING SALMON CAVIAR
8.8 ARTIFICIAL CAVIARS

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8.0 PROCESSING DIFFERENT SPECIES

8.4 STURGEON FISHERIES

Commercial sturgeon fisheries in Canada are practically extinct. Except for the Caspian Sea fishery, sturgeon fisheries barely exist throughout the world. This is the result of stock over-exploitation during the 'caviar rush' at the turn of the century. In the last dec-ade, other factors such as hydro construction on rivers and pollution greatly contributed to this decline.

The dramatic collapse of the sturgeon fishery is a matter of biology. Sturgeon, unlike salmon, spawn several times during their lifetime. They mature and return to spawn for the first time when 10-25 years of age. That is why, if spawners (females with mature ovaries) are withdrawn from a particular population and unregulated fishing continues, that population is doomed to disappear.

Sturgeon represent one of the oldest groups of fish, they are in fact relicts of eras dating millions of years ago. Similar to salmon, they are anadromous, i.e. they are bom in freshwater, migrate to the sea and return to rivers for spawning. There are sturgeon spe-cies who are adapted to spend their entire life in freshwater bodies. The Caspian Beluga lives 70-80 years, spawns every 5-10 years (starting with age 17-20), and produces 200,000 to 2,500,000 million eggs. Beluga's weighing close to 800 kg are reported.

The white sturgeon spawns in pacific coast rivers from Alaska to San Francisco. Younger females return to spawn at intervals of 4 years, older females at intervals of 9-11 years. Egg numbers vary from 700,000 for a 35 Ibs. female to 3-4 million in the lar-ger females. They may live up to 100 years. In the Fraser River, females mature at 26-34 years of age.

It is difficult to find sturgeon fishery and caviar processing statistics. Information from different sources is often contradictory. Table 8-2 characterizes the world's sturgeon fisheries in 1979 -1988 (Soviet sources). Table 8-3 shows the potential caviar process-ing resources of Russia and Iran taken as -5% of the sturgeon catch.

TABLE 8-2

WORLD STURGEON CATCH IN TONS

CO-UN-TRY	YEAR
CO-UN-TRY	1971	1972	1978	1979	1980	1981	1982	1983	1988
USSR	19,100	20,400	24,958	26,322	26,697	26,452	25,704	25,570	18,470
Iran	2,400	2,200	1,801	1,578	1,429	1,496	1,450	1,500	1,700
U.S.A.	700	700	553	246	148	360	321	321	314
China	Not available								300
Canada		100	133	128	163	131	129	79	30
Ruma-nia	200	200	65	61	39	70	64	76	17
Total World Catch	22,400	23,800	27/646	28,459	28,526	28,558	27,718	27,582	21,440

TABLE 8-3

POTENTIAL STURGEON CAVIAR PROCESSING, IN TONS

COUNTRY	YEAR
COUNTRY	1971	1972	1978	1979	1980	1981	1982	1983	1988
USSR	850	1,020	1,200	1320	1,330	1,320	1,280	1,270	923
Iran	120	110	90	80	70	75	70	75	85

The dominant species in the Caspian Sea fishery are Beluga, Osetra and Sevruga. Other fisheries are the Black Sea (-1,000 tons), Siberian freshwater bodies (-100 tons) and Amur River (-70 tons). The Amur is the only place in the world inhabited by Kaluga sturgeon. Figure 8-6.

FIGURE 8-6: Sturgeons

a & b) Kaluga, , Astrachan Museum, Russia
d) Sevruga, Ural Amur River, China
c) Record size Beluga River, Kazachstan

Potential Canadian commercial fisheries sturgeon species are: the white sturgeon in B.C., the Atlantic sturgeon in New Brunswick and the lake sturgeon (Manitoba lakes and the Great Lakes).

The dynamics of the sturgeon fisheries in the Caspian Sea can be seen in Table 8-4. The decline in the valuable Beluga catch may signal bad news for the sturgeon caviar indus-try. The decline in the sturgeon commercial fishery in B.C. can be seen in Table 8-5. Between 50 and 90% of B.C. sturgeon are caught in the Fraser River, the remainder is a bycatch in salmon gillnet fisheries. Similar declines can be observed for each and every Canadian water body where sturgeon were commercially fished in the past: Nelson River (Manitoba), St. Johns (New Brunswick). These reported landings do not include sports fishermen's catches and native food fishing.

TABLE 8-4

STURGEON FISHERIES IN CASPIAN SEA

YEARS	TOTAL CATCH IN TONS	BELUGA IN % OF TOTAL CATCH
1899	23,810	27
1900	28,230	27
1901	35/390	24
1902	39,070	31
1903	39/230	38
1904	30,660	42
1905	26,630	47
1906	30,990	42
1907	27,540	39
1915	28,720	13
1917	7,290	28
1918	3,420	18
1924	8,740	18
1925	12,090	17
1926	13,500	20
1935	19/350	26
1936	21,460	30
1939	11,300	27
1940	7,480	21
1944	3,360	26
1947	9,370	18
1948	11,190	18
1952	12,810	10
1953	11,670	7
1960	10/140	11
1961	13,040	11
1962	19,330	10
1975	23,200	7
1990	13,600	8

TABLE 8-5

WHITE STURGEON CATCHES IN B.C.,
1880-1991 IN TONS

1880	36	1910	249	1940	7	1970	18
1881	32	1911	235	1941	10	1971	15
1882	36	1912	229	1942	4	1972	17
1883	181	1913	49	1943	8	1973	18
1884	160	1914	52	1944	12	1974	17
1885	161	1915	37	1945	14	1975	21
1886	52	1916	33	1946	8	1976	22
1887	113	1917	20	1947	21	1977	33
1888	93	1918	5	1948	11	1978	29
1889	144	1919	10	1949	19	1979	23
1890	182	1920	6	1950	15	1980	19
1891	147	1921	9	1951	12	1981	10
1892	236	1922	15	1952	18	1982	8
1893	150	1923	26	1953	25	1983	3
1894	269	1924	14	1954	12	1984	8
1895	170	1925	12	1955	16	1985	8
1896	173	1926	12	1956	16	1986	5
1897	516	1927	15	1957	14	1987	6
1898	340	1928	12	1958	22	1988	4
1899	126	1929	14	1959	17	1989	8
1900	48	1930	12	1960	15	1990	9
1901	29	1931	11	1961	15
1902	15	1932	9	1962	13
1903	14	1933	45	1963	13
1904	15	1934	9	1964	16
1905	9	1935	20	1965	12
1906	11	1936	6	1966	12
1907	45	1937	4	1967	10
1908	81	1938	8	1968	11
1909	227	1939	7	1969	19

The record annual B.C. landing of 516 tons was reported in 1897 and the record mini-mum of 4 tons in 1937 and 1988. On August 14th, 1897 a 1/387 Ibs. fish was taken at New Westminster. In August 1981, the record sturgeon caught in the Hope area weighed 650 Ibs. As a rule of thumb, one can estimate caviar yield as 5% of total catch. B.C. regulations do not allow the taking of sturgeon outside the range of 100 to 200 cm (measured from the tip of the snout to the tip of the tail).

Today caviar processing does not exist on the Fraser River. Caviar processing takes place only on the St. John River (N.B.) where several hundred pounds of caviar are processed yearly, see Figure 8-7. Thus, in fact, sturgeon caviar is not commercially produced in Canada. Sturgeon caviar from New Brunswick has a superb sweet yolky taste similar to the Caspian sevruga caviar.

FIGURE 8-7: Sturgeon Caviar Processing in Canada

a & b) Atlantic sturgeon/ St. John River, N.B.
c) Ovaries
d) Caviar

This manual discusses sturgeon caviar processing issues because Canada imports sev-eral thousand pounds of sturgeon caviar yearly. All of it packed in retail packages in Russia or repacking countries such as the U.S.A. or Germany. Considering the high wholesale prices (200 to 900 $ per kg) sturgeon caviar constitutes a substantial part of the caviar trade. That is why repackers, distributors and consumers should be educated in all as-pects of sturgeon caviar processing in order to make intelligent business decision.

In recent years sturgeon rearing has been successful and there is speculation that cul-tured-in-captivity stocks could become a resource for caviar production. These suc-cesses are truly remarkable. For over ten years, hundreds of millions of sturgeon of all species are released annually by a dozen Russian and one Iranian hatchery. The number of hatchery sturgeon of all species introduced into the Caspian Sea annually exceeds 100 million frys. The spawners are taken from the wild. It is estimated that about 80% of Beluga and 25% osetra and sevruga in the current catches are hatchery grown and re-leased fish. Hatcheries grow 2-3 gram fish and then the fish are reared further in sea pens or ponds to 50-60 grams. Marketable size sturgeon farming, based on wild and domesticated broodstocks/ started originally in Russia and now there are similar devel-opments in many other countries i.e. France, Italy, Spain, Germany, Japan and the U.S.A.

Sturgeon farming in freshwater or brackish water pens and ponds in Russia, and to some extent in the U.S.A., is now an economically viable industry. The Russians produce 500 tons of farmed sturgeon per year. The main species involved are the so called Bester (a hybrid of Beluga and Sterlyat), Sterlyat and sterile hybrids of Oestra and Beluga, See Figure 8-8. In the U.S.A., the main product of farming is the White sturgeon. To obtain marketable size fish, they are grown to 3 years. In the first year they reach the weight of 200 grams and subsequently 1.0-1.2 kg and 1.5-2.5 kg. With good water quality and year round 18-22°C water temperatures, the same growth results are achieved in 2 years. The most promising economical and biological performance is achieved by Bester. Af-ter growing to 5-7 grams the mortality rates for Bester are nil. The success with Bester, Russian Osetra and Siberian Osetra broodstock management for almost 30 years pro-vides for realistic planning of full cycle sturgeon farming facilities, which will produce caviar. The economic viability of processing caviar from farmed sturgeon is based on the following considerations:

FIGURE 8-8: Bester

a) 5 month old juveniles
b) 3+ year pond grown 7 Ibs, Russia

Injections into the hypothalamus enhance the maturation process and decrease the inter-val between two maturations of the specimen to 1-2 years.

The eggs can be extracted by surgical procedures. The ability of the female to ripen again enjoys a success rate of 70-80%.

Some species (like Bester or White sturgeon) may mature in captivity after 5-6 years of rearing. At age 9-13, the ovaries yield 11-17 kg per fish.

The popularity and high price of sturgeon caviar makes it attractive and viable to farm sturgeon for caviar. At the moment, such an industry does not exist but numerous ex-perimental lots have been produced.

One of the difficulties encountered with this method is that when eggs are taken before the 'running' stage, i.e. the eggs are not yet mature, the mortality rate of the fish is higher. At the same time the best caviar is obtained from eggs taken before the 'running' stage. It is a technological challenge which can be solved. Development of a caviar industry from farmed sturgeon will lift the pressure from wild stocks which in turn will lessen the danger of their depletion or even worse, their extinction.