COMMERCIAL Alango Canning t • IN HAWAII

G. DONALD SHERMAN• SEIJI SAKATA• R. A. HAMILTON

Hawaii Agricultural Experiment Station University of Hawaii Circular 54 June 1958

CONTENTS

PAGE

SELECTION OF FRUIT • 6

PREPARATION OF FRUIT FOR PROCESSING 7

EXPERIMENTAL PACKS g

RECOMMENDED PROCESS • 12

ECONOMICS OF CANNING MANGOES 12

SUMMARY 14

LITERATURE CITED 14 THE AUTHORS DR. G. DONALD SHERMAN, Senior Soil Scientist at the Hawaii Agricul­ tural Experiment Station, Head of the College of Agriculture Department of Agronomy and Soil Science, and Senior Professor of Agriculture, Uni­ versity of Hawaii, is Director of the Food Processing Laboratory. SEIJI SAKATA was Analyst at the Food Processing Laboratory, 1952-56. DR. RICHARD A. HAMILTON is Horticulturist at the Hawaii Agricultural Experiment Station and Professor of Agriculture, University of Hawaii.

ACKNOWLEDGMENT The funds and facilities which made possible this report on the com­ mercial canning of mangoes were supplied through a grant to the University of Hawaii by the Industrial Research Advisory Council (now known as the Economic Planning and Coordination Authority, Territory of Hawaii). COMMERCIAL CANNING IN HAWAII

G. Donald Sherman, Seiji Sakata, and R . A. Hamilton

There has been a limited increase in mango production in the Hawaiian Islands due to new plantings which are beginning to bear heavy yields of improved quality fruit. Yields have been very irregular so that the fruit available for the fresh fruit market may be very scarce one year and the next year may exceed the market demand. In years when there is a surplus, there is a need for a means of taking care of it. l\fangoes cannot be ex­ ported as fresh fruit to the Mainland because of the mango seed weevil. Entomologists have not been able to control the weevil with insecticides presently available. This study was undertaken to develop the best method of preservation of mango fruit in years when the supply exceeds consumer demand. There are a number of preservation methods available which are as follows: (1) coating the surface of fresh fruit with materials to protect it from decaying, extending its storage life; (2) dehydration; (3) c;mning; and (4) quick freezing. In this study the method of preservation which was considered was canning. Experimental packs were made during the 1953, 1954, and 1955 seasons. India has grown a large acreage of mangoes for many years. Studies have been made there of methods of preserving the fruit in order to extend the use of it as a food. India produces two types of mangoes. One is a juice mango while the other, which has firmer flesh, is used as a dessert fruit. Lai et al. (2) canned mangoes in a 40° Brix sirup containing 0.5 percent of added citric acid. The canned fruit was heated to 212° F. for 25 minutes. Siddappa and Bhatia (5) heat processed mangoes in an acidified sirup containing from 0.1 to 0.5 percent of added citric acid depending on acidity of the fruit. They also blended it with other acid fruits. The blends with orange and pineapple juices were of excellent quality and were acceptable. Basu (1) made one of the most comprehensive studies on the preserva­ tion of mangoes. In his studies he preserved mangoes by the following methods: I. Wax coatings: The mango fruit was dipped in melted paraffin at 80° C. for 10 seconds and then stored at 55° F., which extended the storage period of mangoes to 46 days while the untreated fruit spoiled in 12 days. Dipping the fruit in 50 percent paraffin in a petroleum ether increased the storage life 15 days at 55 ° F.

5 2. Canned fruit: Mangoes canned as sliced fruit in sirup kept well from 90° to 115° F. The addition of calcium chloride improved the texture of the pack. 3. Dried fruit: Mangoes were dried as a powder. The dehydrated man­ goes were stored for eight months but were hygroscopic. Leverington (3) described procedures for the canning and freezing of Australian mangoes. He recommended canning of mango slices and cubes in a 35° to 40° Brix sirup with added citric acid to insure satisfactory preservation. He obtained a yield of 30-35 percent slices and cubes from common mango and 45-55 percent in the case of the Kensington variety of mangoes. Mangoes are canned commercially in Mexico, the Philippine Islands, India, and Costa Rica. The first two pack most of the fruit as irregular­ sized chunks and as halves. Costa Rica packs a canned mango juice. Orr and Miller (4) have studied the adaptability of different mango varieties in Hawaii to quick freezing.

SELECTION OF FRUIT A number of varieties of mangoes are grown in the Hawaiian Islands, all for the fresh fruit market. The demand for fresh fruit is excellent. The bearing habits of the mango are very irregular due to disease anthrac­ nose, which attacks the flowers and small fruit, and physiological reasons. The pattern of yields is alternating years of heavy and light production. During each year of good yields, a growing surplus of fruit has been flood­ ing the markets. This surplus is due to increased plantings of the fruit in both commercial or semicommercial orchards and on backyard trees. Home plantings contribute to the surplus whenever the trees yield more than the owners can consume. This surplus is either preserved or sold as fresh fruit for the added income it furnishes the family. In 1954 the largest commercial grower in the Islands canned the surplus fruit to avoid spoilage. In 1955 another larger grower preserved a large part of his crop by quick freezing. The surplus fruit is not large in total tonnage, approximately 50 tons, but indications are that the volume will increase in the future. The most common varieties grown in the Islands ate the , Pirie, and . Sandershaw, Shibata, Ameeri, , Late, , and Joe Welch are also grown to a limited extent. Juice mangoes are not grown in the Islands. The following four varieties were selected for this study: Haden Fruit large, plump, and oval; up to 6 inches in length and 24 ounces in weight; apex rounded, no beak. Ground color, yellow with a crimson blush over exposed portions of the fruit. Flesh is 5weet, juicy, subacid, and almost fiberless. Quality good. Tree is upright, vigorous, and considered fairly productive in dry areas in Hawaii. Originated in as a seedling of Mulgoba. It was imported into Hawaii about 1930. There are probably more grafted Haden trees in Hawaii than there are trees of

6 Zill Fruit small to medium in size, ovate; up to 4 inches long, to 3 inches thick, and 12 ounces in weight. Ground color is yellow, with an attractive crimson blush usually extending over at least half of the surface. Small beak located about Yz inch above the rounded apex. Flesh orange-yellow, firm, juicy, and fiberless. Flavor rich, sweet, and aromatic; quality very good. This variety, which originated in Florida, is said to be a Haden seedling. It was introduced into Hawaii about 1945. In Florida it is considered productive and consistent in bearing habit.

Joe Welch or Mapulehu Fruit medium in size; plump; oblong-ovate; 3-4Yz inches long, 2Y2-3 inches thick, and up to 16 ounces in weight. Ground color is orange-yellow with a slight reddish blush on the exposed cheek. Conspicuous beak located about Y2 inch above the apex; apex rounded; seed, medium in size, with very little fiber. The stem is attached squarely. Flesh is juicy and firm enough so that it holds together well in canning and freezing. Quality and flavor are fair to good, depending on locality and season. Originated from a seed planted by Joe Welch on Molokai. Production appears to be relatively good and off-season fruiting is common with this variety. It has been propagated and distributed to a limited extent since about 1942 through the Hawaiian Sugar Planters' Association Experiment Station. The only sizeable orchard of this variety is found at the H.S.P.A. Quarantine Station at Mapulehu, Molokai.

Ah Ping Fruit medium to large; up to 6 inches long, to 3Yz inches thick, and up to 18 ounces in weight. Shape oblong and plump, with a rounded apex and no beak. Ground color, orange-yellow with an attractive crimson blush on well-colored specimens. Prominent white lenticels. Flesh is firm, sweet, and yellow with very little fiber. Quality, good. The original seedling tree on Molokai has been a good producer. Only a few trees of this comparatively new variety have been grafted and these have not come into production, so the bearing behavior in other areas has not yet been determined.

PREPARATION OF FRUIT FOR PROCESSING A good processed fruit product, canned or frozen, requires careful se­ lection of top-quality fruit. A processing plant operating with this type of fruit will always produce superior quality product£ at a lower cost of operation. Mango varieties vary considerably in flavor, firmness of flesh, fiber con­ tent, and size and shape of the seed. In selecting fruit for canning, the fruit should have the following characterstics: I. A good mango flavor is essential in order to retain the mango flavor in the canned product. Mangoes have a delicate flavor. Many of the mango

7 varieties when canned develop a flavor which resembles the flavor of peaches. Some varieties will retain a mango flavor in a canned product. 2. A good canning mango must be firm and free from tough fibers in order to produce a firm slice or chunk in the finished product. 3. The flesh of the mango must have a bright orange or orange-yellow color in order to make an attractive product. 4. The fruit should be free of spoilage or blemishes. If the fruit has soft spots or blemishes, it should be trimmed. Trimmed fruit should be used in sliced or diced fruit packs; or if it has a tendency to be soft, it should be used in a puree pack. Firm ripe fruit shoulrl be used in all packs. The first step in the preparation of mangoes for processing is the wash­ ing and grading of the fruit. The fruit should be washed in order to re­ move adhering materials and to give a clean surface for grading. The fruit should be peeled by a method that completely removes the peel. The peel carries taste constituents which are undesirable in the finished product. Hand peeling, while efficient in the removal of the peel, is an expensive operation. Some form of mechanical operation should be considered. Pear peelers can be adapted to do a satisfactory removal of the peel if the fruit is firm and sound. Chemical and heat methods are not satisfactory for peeling mangoes because of the physical nature of the fruit. The fruit will be in better condition for the slicing and dicing operation which follows if peeled mechanically. The fruit can be checked for im­ perfections after mechanical peeling and before slicing. The stem-end flesh should be trimmed as it is a source of off-flavor. After peeling, the fruit is cut into appropriate-sized slices or chunks for canning. The fruit of the mango has well-developed cheeks; thus, it is possible to prepare packs consisting of the cheeks, or the cheeks can be cut into slices, diced, or cubed. The shape of the fruit and the width of the seed will determine the type and size of slice or cube which is canned. A thin seed would be very desirable in a commercially canned mango pack. The slices prepared in this laboratory varied from Y:!" X l" X 2Y-i_" to Yz" X lY-i_" X 3". The "cubed" packs were prepared by a o/4-inch dicer. The waste from these packs is collected and made into a puree from which other mango products are prepared. The sliced or cubed fruit is packed tightly into plain tin cans (13 ounces net weight of fruit in No. 2 cans) . The fruit can also he packed in glass containers. When packing is done in glass containers, the fruit should be carefully packed in order to give the most attractive appearance possible. Sirup of the required concentration is heated to 190° F. and is then added to the fruit in the containers. Prolonged heating of the sirup should be avoided because of browning. The packs are placed in an exhaust box, which is then heated until the internal temperature of the filled container reaches 165° F. (usually 5 minutes), after which they are immediately sealed by the sealing machine.

8 The sealed cans are next placed in a boiling water bath and cooked for 20 to 25 minutes for No. 2 cans (307 X 409). They are then removed and cooled at room temperature.

EXPERIMENTAL PACKS Experimental packs were prepared in 1955 by the foregoing procedure from the fruit of the Zill, Haden, Ah Ping, and Joe Welch varieties. The fruit was packed as "sliced" and "cubed" fruit in sirups ranging from 30 to 50 percent sugar. In addition, citric acid was added to certain packs. The various packs were stored and examined at various intervals. The data presented in table 1 show the recovery of canned mango products from a typical pack of each variety. The percentage of fruit re­ covered as sliced or cubed fruit available for canning was the highest in Haden variety, 57.6 percent, and lowest in the Joe Welch variety, 41.4 percent. The percentage of recoverable fruit pulp ranged from 54 to 69 percent, with fruit of the Zill variety the lowest, and fruit of the Haden variety, highest. These recoveries compare favorably with those obtained by Leverington (3). The recoverable fruit for canning from any variety will vary considerably in different lots of fruit. The size of the fruit will have a major influence on the percentage of recovery in the form of finished products. The fruit of the Ah Ping and Joe Welch varieties gave the high­ est yield of slices and chunks because the fruits were larger than fruit of the Zill and Haden varieties. Haden fruits are often larger than the fruit used in these packs.

TABLE 1. The recovery of pulp and canned products from samples of each variety of mango in packs made during August, 1955

PROCESSING RECOVERY WEIGHT OF VARIETY SAMPLE Canned POUNDS Peeled fruit sliced or chunk Seed and peel percent percent percent Zill 66.5 54.0 50.4 46.0 Haden 55.0 69.0 57.6 31.0 Ah Ping 58.3 57.9 47.2 42.l Joe Welch 148.5 55.7 41.4 44.3

The data presented in table 2 show the results of chemical control tests conducted during storage. The pH and cut-out Brix remained constant throughout the storage period which indicates complete heat sterilization of the packs. All packs were in good condition during the entire storage period. The packs of Joe Welch were less acid than the packs of the fruit of other varieties and should have citric acid added to insure complete

9 TABLE 2. The results of chemical control tests on samples of different packs of the four mango varieties after certain periods of storage

pH CUT-OUT BRIX CAN VACUUM TYPE SIRUP VARIETY OF 0 BRIX 6 weeks 3 months IO months PACK 3 months IO months 6 weeks 3 months IO months (9 percent) (inches of Hg.) 30 4.10 4.18 4.10 23.0 23.7 Chunk 23.8 14.0 Zill 40 4.04 4.18 4.08 26.1 27.1 27.4 14.0 (packed 30 4.11 4.18 3.97 23.0 23.0 23.6 16.0 7-25-55) Sliced 18.7 40 4.01 4.04 4.05 26.8 26.7 27.9 16.0 13.5 30 3.95 4.06 3.98 20.3 20.5 21.8 Chunk 17.0 12.4 Haden 40 3.96 4.03 3.99 24.5 25.1 25.6 16.8 10.4 0 (packed - 30 3.98 4.00 3.97 20.3 20.9 21.4 7-25-55) Sliced 17.0 16.2 40 4.01 4.13 3.94 24.9 25.8 25.0 16.5 12.3

Ah Ping 30 4.29 4.19 21.5 20.3 21.7 Chunk 13.0 9.6 (packed 40 4.18 4.19 4.13 26.0 25.9 26.5 14.0 8-15-55) I 12.2 30 4.49 4.48 4.42 21.0 20.6 21.1 16.0 Chunk 11.7 Joe 40 4.51 4.50 4.42 26.0 25.3 25.4 14.2 10.0 Welch 40 4.44 4.47 4.40 24.7 24.3 23.5 18.0 10.5 (packed 50 4.50 4.33 29.3 29.4 29.2 10.0 8.2 8-15-55) Sliced 50 plus 0.5% acid 4.33 4.38 4.25 29.8 29.0 29.5 10.3 8.3 sterilization. The reaction of the Joe Welch packs ranged from pH 4.3 to pH 4.5 while the reaction of the packs of other varieties ranged from pH 4.0 to pH 4.3. The most acidic packs were those of the Haden variety. All packs of mangoes have been completely sterilized without the addition of acid. The organoleptic tests were conducted at each cutting in the storage period. The tests were not conclusive as no pack was picked as being clearly better than the others. The general observations are summarized in table 3. The data presented in this table should be considered a trend of public reaction to the products. Several observations, however, can be made from the organoleptic tests, and they are as follows: I. All packs of the fruit of the varieties Zill, Joe Welch, and Haden were considered good by the majority of the samplers (14 out of 15). 2. The packs of the variety Ah Ping were definitely inferior, being rated good by only 1 of the 15 samplers. 3. The samplers who liked the taste of the mangoes having a mild turpentine taste preferred the packs of the Joe Welch variety. They also preferred this variety packed in heavy sirup containing citric acid. 4. The samplers who preferred milder flavored mangoes selected the packs of the Zill and Haden varieties. 5. The samplers preferred the packs in 40° Brix sirup to the same fruit packed in a 30° Brix sirup (9 out of 15). 6. The heavier sirup packs apparently improved the fl avor by greater retention of flavor within the fruit. 7. The packs of all four varieties used were considered superior to any of the foreign mango packs presently sold on the American market. The results of this study indicate that excellent canned mangoes can be made with the process described.

TABLE 3. The general rating of the different packs of the different varieties of mangoes

FLAVOR COLOR TEXTURE I. Joe Welch chunks, packed in 40° Brix sirup I. Joe Welch I. Haden 2. Joe Welch chunks, packed in 30° Brix sirup 2. Haden 2. Zill 3. Zill slices, packed in 40° Brix sirup 3. Ah Ping 3. Joe Welch 4. Zill slices, packed in 30° Brix sirup 4. Zill 4. Ah Ping 5. Zill chunks, packed in 40° Brix sirup 6. Zill chunks, packed in 30° Brix sirup 7. Joe Welch slices, packed in 50 ° Brix sirup with citric acid 8. Haden slices, packed in 40° Brix sirnp 9. Haden chunks, packed in 40° Brix sirup IO. Haden slices and chunks, packed in 30° Brix sirup

11 RECOMMENDED PROCESS The process tentatively recommended for commercial processing of mangoes is as follows (fig. 1) : l. Fruit should be washed and graded before peeling. All blemishes should be removed at this stage. 2. The fruit should be peeled mechanically. All of the peel should be removed. 3. The peeled fruit should pass over an inspection table for misses in the peeling operation. The fruit should be sized to give uniformity in the size of chunks or slices in the finished product. Off-colored flesh at stem end is cored out to eliminate off-flavors. 4. The fruit is sliced longitudinally so as to obtain two symmetrical cheeks. These cheeks can be canned or passed through other cutters which cut them into chunks of the size desired. The seed will then be trimmed by hand to recover additional chunks or passed through a stripper to re­ move the remaining pulp. 5. The cheeks, slices, or chunks are placed in appropriate containers and a 4Q° Brix sirup added. The filled cans are exhausted to a center tem­ perature of 165° F. They are then sealed in the can-closing machine and processed for the prescribed time in a boiling water bath to a center tem­ perature of 195° F. (approximately 10 minutes) . The cans are cooled to room temperature and labelled. 6. The pulp which has been removed from the seed and the juice which has accumulated from the slicing operation is passed through a finishing machine using a .062-inch screen. The pulp can be heat pro­ cessed by the same method as the chunks, beginning with filling of the container. The canned puree can be either pasteurized or quick frozen.

ECONOMICS OF CANNING MANGOES The price of the mangoes will determine the success of any commercial development of processed mango products. If a processor is packing fruit in one-pound containers, his fixed costs will range between 12 and 16 cents a can. This includes all costs except the cost of the fruit which goes into the pack. The packer, in order to be competitive with other products, would have to keep the cost of production below 25 cents per can. Higher production costs would limit the market to the specialty trade. It is likely that any early development of mango processing in the Islands will be limited to this specialty market as the lowest price acceptable to the grow­ ers would probably be about $200 per ton. This would make the cost of fruit for a one-pound container about 15 to 18 cents depending on the percentage of recoverable canned mango products from the fruit. The resulting retail price of this product would probably place it in the specialty market. Even this would permit the canned H awaiian mango products to compete to advantage with imported mango products.

12 WASHER

MECHANICAL PEELER

GRADING a INSPECTION

SLICER MACHINE

SEEDS a SIZER a LOOSE PULP SLICER

TRIMMING TABLE

CHUNKS CHEEKS

PULP 8 PACKING IN SEEDS JUICE CONTAINER

FINISHER 0 .062 SCREEN SIRUPER

PACKAGING EXHAUSTER

QUICK FROZEN CAN CLOSER PUREE FREEZING COOKER

CANNED CHUNKS CANNED SLICED

FIGURE 1. Flow sheet for the commercial processing of mangoes.

13 SUMMARY The Food Processing Laboratory of the Hawaii Agricultural Experiment Station has developed a process for the commercial canning of mangoes based on the results of experimental packs over a three-year period. The mangoes were packed as cheeks (halves), chunks, and slices in unacidified and acidified 40° Brix sirup. Mangoes canned by this process retained their flavor and have maintained their quality over a two-year storage period. A typical flow sheet of the recommended process has been developed. Excellent and satisfactory canned mangoes have been prepared from the fruit of the Haden, Zill, and Joe Welch varieties. The packs of the Ah Ping variety were inferior in quality as compared to the other three varieties used in this study. The recovery of canned fruit from all varieties ranged from 54 to 69 percent of the gross weight of the fruit. The packs of Joe Welch, Zill, and Haden were well accepted on taste tests but differ­ ences between the three varieties were not significant.

LITERATURE CITED

1. BASU, G. 1954. PRESERVATION OF THE MANGO, Indian Food Packer 8: 15-17. 2. LAI, G., G. L. TANDON, and J. D. PRUTHI. 1952. PILOT PLANT TRIALS ON THE PROCESSING OF CANNED MANGOES AND MANGO SQUASH. Chem. Agr. India 6: 103-109. 3. LEVERINGTON, R. E. 1953. MANGO PROCESSING. Queensland Fruit and Vegetable News 4: 438-439. 4. ORR, K. J. and C . D. MILLER. 1955. DESCRIPTION AND QUALITY OF SOME MANGO VARIE· TIES GROWN IN HAWAII AND THEIR SUITABILITY FOR FREEZING. Hawaii Agr. Expt. Sta. Tech. Bul. 26. 5. S1DDAPPA, G. D. and B. S. BHATIA. 1956. lloLE oF pH IN THE CANNING oF MANGoEs: EFFECT OF ADDING ACID OR OTHER FRUIT TO THE CANNED PRODUCT. Food Research 21: 165-169.

14 UNIVERSITY OF HAWAII COLLEGE OF AGRICULTURE HAWAII AGRICULTURAL EXPERIMENT STATION HONOLULU, HAWAII

WILLARD WILSON Acting President of the University H. A. WADSWORTH Dean of the College MORTON M. ROSENBERG Director of the Experiment Station