EFFECTS OF PHOMOPSIS PEACH ROT ON PULP LOSSES AND PUREE QUALITY

The effects of a Phomopsis sp. on four peach (Primus persica) cultivars and three fruit maturities were evaluated for pulp losses and quality changes of peach puree. Fruits were inoculated with 2 mm × 2 mm of agar with Phomopsis mycelium and incubated at room temperature (24 to 26 C) for 3 days. The early-maturing cultivar Goldilocks had higher susceptibility to Phomopsis than the late maturing Babygold 8. Mature fruit had a slightly higher degree of susceptibility to Phomopsis than less mature fruit, except for Goldilocks, which showed equal susceptibility at all maturity stages. Pulp losses, percentage of decayed tissue, titratable acidity, Howard mold counts, soluble solids (SS), SS/acid ratio, viscosity, pH and changes in color were variable among cultivars and maturities. Puree made with 1% or more Phomopsis-decayed tissue may be unacceptable because of a high (16–75%) mold count.     

STABILITY OF GUAVA PUREE CONCENTRATE DURING REFRIGERATED STORAGE

SUMMARY— Guava puree concentrate, containing 1000 ppm potassium sorbate, showed no gross signs of spoilage during storage for 5 months at 45°F. During this period, the initial number of yeasts (the predominant spoilage organisms) decreased steadily to an insignificant level. Flavor and aroma quality were good and did not deteriorate appreciably until the fourth month of storage. Browning of the concentrate was apparent after 2 months and became more pronounced with continued storage. The browning may be related to a rapid loss of ascorbic acid that was virtually complete after 1 month. The carotenoid level, on the other hand, remained constant during the 5-month storage period.     

EFFECTS OF LONG-TERM STORAGE ON QUALITY OF PROCESSED FOODS

Experiments were conducted on the effects of long-term storage at 4.4, 21.1, and 37.8°C temperatures on nutritional quality, physicochemical characteristics and organoleptic quality of 8 food packets (ready to eat individual ration items processed in flexible retortable pouches) of ham and chicken loaf, beef steak, beef stew, frankfurters, fruit cake, pineapple slices, cheese spread, and chocolate brownies. At 37.8°C storage life of cheese spread, pineapple slices, beef stew, chocolate brownies and fruit cake was 12, 12, 30, 30 and 30 months respectively. Ham and chicken loaf, beef steak, and frankfurters were acceptable after 37.8°C storage for 54 months, but frankfurters were near the borderline of rejection. The browning is usually associated with the high temperature storage of high sugar foods. Meat products except beef stew are apparently more stable than others at high temperature storage. The high temperature storage resulted in drastic loss of thiamin and ascorbic acid, significant loss of riboflavin and niacin, and discoloration and rancidity. Despite the losses of quality observed in all food packets stored at 21.1°C for 54 months, they were acceptable. Storage at 4.4°C for 54 months had very little effect on quality of the food packets and were highly acceptable.     

IMPACT OF IMMATURE FRUITS ON QUALITY OF PEACH PUREE1

Peaches (Prunus persica L. Batsch) were sampled during the early harvest season to determine the percentage of immature fruits harvested in commercial orchards. The results indicated that the earlier the harvest, the higher the percentage of immature fruits (24%). Six days after the harvest season started, the percentage of immature fruits stabilized to 13%. Removal of immature fruits decreased acidity, increased soluble solid/acidity ratio but did not affect soluble solids content in peach puree. Color was improved by the removal of immature fruits in the cultivar (cv) Baby Gold 5, but no effect was noted in Allgold; puree of the cv Baby Gold 7 showed an improvement in color in 1989 but no effect in 1988.     

EFFECTS OF LONG-TERM STORAGE OF FOODS ON QUALITY OF PROCESSED FOODS II.

The effects of long-term storage at 4.4, 21.1, and 37.8°C on physicochemical characteristics, nutritional and organoleptic qualities of freeze-dehydrated ration items from Packet Long Range Patrol were studied. The items included beef hash, beef stew, chicken stew, spaghetti with meat sauce, chili con carne with beans, chicken and rice, pork with escalloped potato, and beef and rice. The freeze-dehy drated foods were stable in quality during storage at 4.4, 21.1, and 37.8°C. After 44 months of storage all freeze-dehy drated ration items were in acceptable condition.     

EFFECTS OF SODIUM LACTATE, SODIUM ACETATE AND SODIUM DIACETATE ON MICROBIOLOGICAL QUALITY OF VACUUM-PACKED BEEF DURING REFRIGERATED STORAGE

Beef samples were cut into the pieces and treated with solutions of 1.8 and 2.5% sodium lactate (SL), 0.1% sodium acetate (SA), 0.1 and 0.2% sodium diacetate (SDA) and their combinations, packed under vacuum and stored in a refrigerator at 4C. Microbiological quality of the samples was investigated during their storage for 21 days. Sodium salts and their combinations significantly (P < 0.05) affected the aerobic plate count (APC). Although growth of lactic acid bacteria (LAB), psychrotrophs and coliforms was delayed in treated samples, they were not completely inhibited. The most effective treatment to delay the growth of microorganisms was the combination of 2.5% SL + 0.2% SDA. The count of bacteria of the samples reached and exceeded the spoilage limit (10⁷?10⁸log cfu/g) after 14 days at 4C.     

SODIUM LACTATE EFFECTS ON THE STABILITY OF FRESH AND CURED PORK LONGISSIMUS

Boneless pork loins sliced into 1.9 cm fresh chops were dipped to retain 0, 1.5 or 3% sodium lactate (SL) and packaged in polyvinylchloride (PVC) or vacuum-packaged (VP), Color of fresh chops was monitored visually and objectively. Boneless pork loins were cured by injection with 0, 1.5 or 3% SL, or were dipped after slicing to retain 0, 1.5 or 3% SL. Cure for the dipped loins contained no SL. Color and aerobic plate count (APC) of vacuum-packaged chops were evaluated over 70 days of retail storage (4C). Visual color was darker (P < 0.05) and L* values were lower (P < 0.05) for 3% SL-dipped fresh chops. Fresh chops containing 1.5 and 3% SL had higher a* values than controls. Surface discoloration of 3% SL fresh chops was lower (P < 0.05) than control chops. Cured injected chops (3% SL) had lower (P < 0.05) L* values than dipped chops or injected controls. L*, a* and b* values of cured dipped chops (3% SL) were not different (P > 0.05) from controls. No consistent trends were found in APC of cured chops. Injection of SL prior to cooking darkened the color of cured pork loin chops.