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p. 36 A new index, BrimA (pronounced 'bree-mah' for 'Brix minus Acid') has been proposed by horticultural researchers as an index for measurement of fruit maturity and palatability. It is based on the linear weighted difference between the Brix and the total acid measured rather than their ratio. With it, the Brix reading is modified to account for the sweetness-reducing effect of acids. The Brix/acid ratio is the reading in degrees determined by refractometry over the total acid concentration determined by titration. Topics include the reasons for a new index, review of published data, a nomogram to interpret Brix/acid combinations, BrimA in maturity regulations, geometry of Brix and acid, and pH and other factors. Table grape and grapefruit data are reviewed.

Research is presented concerning the extraction of crushed and intact achenes from the jelly fig for different time periods to investigate the changes occurring in pectinesterase activity. Pectinesterase inhibition is discussed.

A new study compares the quality of hydroponic tomatoes ripened off and on vine. It is shown that vine-ripened tomatoes are redder and darker than off-vie tomatoes.

Research into testing the quality and maturity of oranges.

Research into accelerating the production of black olives.

A study was conducted to examine delayed luminescence associated with tomato fruits during the ripening process. The ultraweak flow of photons resulting from biological systems was determined while the samples were maintained an 20 degrees C. The use of fruit luminescence as a quality indicator of tomatoes was also analyzed by correlating experimental findings with fruit properties and respiration. Results indicated that delayed luminescence can be utilized as a nondestructive tool to analyze the quality of tomato fruits.

Light irradiation affects the ripening characteristics of tomatoes. The greatest effect on color development occurs when tomatoes are irradiated at breaker and turning maturity stages. Exposure to a three min red (R) irradiation enhances red color development. A three min far-red (FR) irradiation delays red color development in breaker stage tomatoes during the first four days of ripening. An interval of one or two days between R and FR treatments yields similar effects and effective color development. R irradiation yields lower firmness values than FR irradiation.

The peel gloss of mature-green tomatoes decreases with ripening at 20 degrees Celsius, while peel roughness increases with chilling conditions and is unaffected by time. Pink tomatoes show similar changes in peel gloss, but their peel roughness is unaffected by chilling. Peel gloss is non-destructively measured with a glossmeter and can be used as an indicator of ripeness.

Green tomatoes were examined to examine the effects of chilling injury on the ripening of the fruit. Mature tomatoes exposed to low or freezing temperature exhibited lower polygalacturonase activity than nonchilled fruits after 10 days of ripening, but had higher extracted pectinmethylesterase activity. Microscopic techniques showed that injury to the fruit tissue causes loss of turgor in the cell wall, leading to the softening of the fruit.

The activities of peroxidase (POD) and polyphenoloxidase (PPO) enhance during papaya ripening and activity peaks of soluble forms are observed when there is a simultaneous rise in protein content. The synthesis of protein with PPO and POD activities precedes the climacteric stage. During freezing and frozen storage of papaya, the POD activity is increased but PPO activity is slightly influenced.

Study of fungi-related post-harvest fruit diseases reveal that fungi, which are dormant in unripe fruit, transform to a multiple infectious structure in response to the fruit's ripening hormone, to trigger the infection process. Post-harvest fungal diseases account for nearly 10 to 50% loss of world food supply. Ripening fruits are more susceptible to post-harvest fungal diseases than green, developing fruits.

Secondary compounds in fruits are thought to be a defense against invertebrates or pathogens which might otherwise damage or destroy the fruits or seeds without contributing to seed dispersal. We incorporated ground, nonripe green or ripe red fruits of American holly Ilex opaca into standard diets of two species of polyphagous caterpillars to test the hypothesis that nonripe fruits are better defended than ripe fruits. Fall armyworm Spodoptera frugiperda larvae grew more slowly on diet augmented with 10% (dry wt) ripe fruits than on control diet with 10% cellulose powder, and slower still on diet with nonripe fruits. However, survival, pupal weight and length of the pupal period were not affected by either treatment. Growth rates and survival of fall webworms Hyphantria cunea were reduced to a similar degree by both nonripe and ripe fruits. Methanolic extracts of nonripe fruits brushed on leaf disks of sassafras, a preferred host, deterred feeding by Japanese beetles Popillia japonica Newman, a highly polyphagous species. Extracts of ripe fruits were not repellent. Saponin content was highest in nonripe green fruits, while tannin levels were highest in ripening fruits. In choice tests, red holly fruits were removed from bird feeders at a faster rate than nonripe green fruits. Levels of secondary compounds in fruits of I. opaca may be a compromise between the continued need to protect the seeds from predispersal damaging agents without deterring potential vertebrate dispersers.

Senescence in apple fruit induces modifications in superoxide dismutase activity (SOD), independent of specific physiological factors. Different cultivars exhibit various SOD levels, with specific physiological conditions affecting the functions of all three SOD metalloenzymes. Environmental and cellular stresses in plants are sensitive to genetic variance in SOD functions.

CIE L measurements of enzymatic browning rate in Golden Delicious apple pulp reveal green apple pulp to have highest browning rate. The browning rate depends on temperature and ripeness of the fruits. The inhibitory activity of ascorbic acid (AA) reduces the browning rate and identifies an exhaustion breakpoint of the AA antioxidant properties.

The descriptive sensory levels of three maturity grades of Cresthaven peaches were compared before ripening, after ripening and after storage. Sensory evaluations were conducted by a trained descriptive analysis panel. Variable Cluster Analysis was used to characterize the implications of the sensory findings. Results indicate that the sensory quality of peaches are dependent on its degree of maturity upon harvesting.

The oil palm is a major factor in the economy of much of South East Asia and maximising the harvest is of major consequence. One important source of loss is the shedding of ripe fruit from the bunches before they reach the factories. Study of the course of abscission reveals unusual processes in the oil palm - and in a few other plantation crops such as dates and coconuts - which suggest practical means of achieving better harvesting regimes and regulation of fruit shedding.

The nucleotide sequence of the genepds from tomato was determined by encoding the carotenoid biosynthesis enzyme phytoene desaturase. It was shown that one polypeptide is responsible for phytoene desaturase activity which catalyzes the introduction of two symmetric double bonds into the carbon chain of phytoene in tomato and cyanobacteria. These findings suggest that zeta-carotene is a product of a single enzyme in the carotenoid biosynthetic pathway in which phytofluene is predicted to be an intermediate between phytoene and zeta-carotene.

The isoenzyme pattern and biochemicalmal changes of peroxidase in mangoes during ripening was studied using Lippens and Smith varieties stored at 12 degrees centigrade and at 85-90% relative humidity. Fruit pH and amount of glucose, fructose, and sucrose had increased values during ripening.The study also showed that different species had dissimilar isoenzyme activity patterns.

One- aminocylcopropane-1-carboxylate (ACC) synthase is a key enzyme involved in ethylene biosynthesis. Using primers complementary to conserved regions of ACC synthase, four ACC synthase related gene fragments were detected and amplified from tomato fruit and tomato suspension cell culture. Characterization of theseACC synthase homologs showed that two homologs are novel sequences. The expression of these homologs was monitored under different conditions which enhance ethylene production. The results showed that ACC homologs are differentially expressed under different conditions.

A study to discover the qualities of FLA 9-20C nonmelting clingstone peaches, and to analyze how ripening and cold storage affect the phystical, chemical and sensory properties of this variety is presented. Clingstone peaches of maturity grades 1 and 2 were put in 0 degrees Celsius storage for 8 weeks. Results showed that there were no notable changes in the physical qualities of both grades, except for an increase in firmness over the 8-week storage. It was found that ripening of both maturity grades of clingstone peaches can be done at 20 degrees Celsius for a 15-day duration and stored for 8 weeks at 0 degrees Celsius without any significant alteration in its characteristics.

A study, quantified by HLPC for clingstone cultivars 'Babygold 5,' 'Babygold 7' and a freestone cultivar, 'Cresthaven,' was conducted on organic acids and their alterations during peach (Prunus persica) fruit ripening. At complete development, 'Babygold 5' and 'Babygold 7' had around 20% citric, 60% malic and 19% quinic acid, but 'Cresthaven' had 35%, 37% and 28% respectively. 'Babygold 5' and 'Babygold 7' showed a rise in malic acid and a fall in citric and quinic acids during fruit ripening, but 'Cresthaven' exhibited little variation in these acids.