Quality changes and internal browning developments of summer pineapple fruit during storage at different temperatures

Pre- and post-harvest salicylic acid treatments alleviate internal browning and maintain quality of winter pineapple fruit

Summary One of the major disorders that develop during storage in Asian pears is fruit internal browning (IB) of the core and/or flesh. The relationship between IB, ascorbic acid (AA) concentrations, total phenolic content (TPC) or polyphenoloxidase (PPO) activity during five months storage was investigated in Asian pear fruit. Mature Asian pear ( Pyrus serotina Rehd.) trees cultivar 'KS' 13 grown on European pear seedling rootstocks were used during the 2006 growing season. Fruit were harvested on August 1 (H1) and August 15 (H2), representing early and late harvest for this cultivar. Fruit were picked according to the maturity standard based on soluble solid content (SSC), titrable acidity (TA), firmness and background colour and stored at 1°C and 80-85% relative humidity (RH). Results indicated that IB incidence was higher in fruit from H2 than H1. The activity of PPO in disordered fruit varied with the intensity of the disorder. Ascorbic acid decreased during long-term storage and was lower in H2 fruit compared with H1 fruit. There was a trend for IB to develop when the AA concentration dropped below a threshold. This threshold value depended on picking date and time elapsed from storage and varied between about 3.3 to 9.4 mg 100 g -1 FW. The amount of TPC declined during storage in both H1 and H2 fruit as PPO activity and intensity of IB damage increased. It is suggested that the lower incidence of IB in earlier harvested fruit was a result of the presence of a higher level of AA and a lower level of PPO activity than in later harvested fruit.

The effect of methyl jasmonate (MeJA) on internal browning (IB) and postharvest quality of ‘Huai-mun’ pineapple fruit was investigated. Fruit were harvested at the green mature stage and dipped in MeJA at concentrations of 0 (control), 10‑2, 10‑3 and 10‑4 M for 5 min prior to storage at 10°C for four weeks. Each week, fruit were randomly removed to room temperature for ripening prior to fruit quality determinations. A completely randomized experiment was conducted with four replications (1 fruit/replication). Data analysis was performed by using ANOVA and means were compared by using DMRT at 95% confidence level. MeJA did not reduce IB development in this study. The internal browning (IB) symptoms limited storage life to only 1.25 weeks after treatment with 10(‑2) M MeJA while it was 1.5 weeks in control fruit and in 10(‑3) M MeJA. A concentration of 10(‑4) M MeJA enabled fruit to be stored for 2.5 weeks. In addition, MeJA significantly (p 0.05) difference. Therefore, the application of 10(‑4) M MeJA could maintain the quality of ‘Huai-mun’ pineapple fruit harvested at a mature green stage for up to 2.5 weeks at low temperature.

Background: Vitamin B12 is the micronutrient, present naturally in animal products. The present study was conducted with the aim of developing a naturally fortified vitamin B12 rich fruit product, which can easily be consumed by vegan population. Methods: Pineapple (Ananas comosus) fruit pulp was fermented with Lactiplantibacillus plantarum 20174 to produce vitamin B12 rich jelly. The selected microbial strain grew well in pineapple (Ananas comosus) fruit pulp matrix. The physiochemical properties and nutritional content were analysed and compared for the jellies prepared from fermented (fermented pineapple jelly or FPJ) and spontaneous fermented (control pineapple jelly or CPJ) pineapple pulp. Both CPJ and FPJ were packed and stored for 30 days at low (4 ºC) and ambient (30 °C) temperature conditions, and were subjected to analysis at 10 days intervals. Results: The Total soluble solids (TSS), pH, and reducing sugars were higher in CPJ than FPJ. The FPJ contained 8.17 µg vitamin B12/100 g, while it was not detected in CPJ. There was no microbial growth detected in FPJ throughout the storage period when stored at 4 ºC, rendering it safe for consumption up to 30 days at both the storage temperatures. The decrease in scores of various sensory attributes during storage was little and the developed FPJ was still in the “liked very much” category throughout the storage period. The vitamin B12 content of FPJ was stable during storage and sufficient enough to fulfil an individual’s daily requirement. Conclusion: The developed fermented pineapple jelly can be recommended as an excellent vegan source of vitamin B12.

ABSTRACT: Fruit storage is beneficial to growers to avoid the exposure of fruits to adverse weather conditions and infestation by pests and diseases that may affect the seed quality. This study was conducted to evaluate the influence of fruit maturity and fruit storage on the germination and vigor of bell pepper. Fruits of California Wonder cultivar were evaluated. A storage of bell pepper fruits (green mature, half-ripe (green and red) and fully-ripe (red)) at room temperature was conducted for 0, 5, 10 and 25 days. The experiment was arranged in a Completely Randomized Design with four replications. Results showed that fruit weight was higher in green mature bell peppers without storage. However, fruit storage was advantageous due to the increase in total soluble solids and dry matter. Heavier dried seeds were obtained from fruits without storage. Half-ripe with five days of storage and fully-ripe without storage exhibited the highest germination percentage and germination index of bell pepper seeds, which was higher than the standard germination rate. However, a shorter mean germination time was observed in green mature and half-ripe fruits after five days of storage. Longer and vigorous seedlings were produced from half-ripe fruits with 25 days of storage.

A series of bread samples stored at various temperatures (4°, 25°, and 40°C) were analyzed by differential scanning calorimetry (DSC) to determine if retrogradation (quantified by DSC enthalpy values) and storage temperature were correlated. The increase in enthalpy values during storage time was dependent on storage temperature. However, the rate of recrystallization was not linear at any of the temperatures studied. The net result was that the enthalpy values tended to converge with time, irrespective of storage temperature. Another effect of the increased storage temperature was an increase in the peak temperature (Tp) of the amylopectin endotherm. This indicates either that storage temperature affects the type of crystal being formed as the starch recrystallizes, or that annealing of crystals occurs at the higher storage temperatures. X‐ray diffractometry of starch isolated from the crumb gave similar diffraction patterns indicating no difference in crystal type among the treatments. In addition, the DSC endotherm became sharper at the higher temperatures. Thus, the increase in Tp was apparently the result of annealing of the crystals at the higher storage temperatures.

硫酸カルシウム, 硫黄華などの硫黄含有物質の施用がダイコンの赤心症発生, 肥大根の硫黄およびポリフェノール含有率に及ぼす影響を調べた.硫酸カルシウム40~80kg•a-1の施用により赤心症の発生が軽減され, 肥大根の硫黄含有率が若干高まった. 過リン酸石灰によっても赤心症は抑制され, 肥大根中のリン, カルシウムおよび硫黄含有率が高まった.炭酸カルシウム施用により肥大根のカルシウム含有率は高まったが, 硫黄含有率は高まらず, 赤心症は抑制できなかった.硫黄華4~16kg•a-1の施用では, 施用量が多いほど赤心症の抑制効果が高く, 肥大根の硫黄含有率が高まった. また, 硫黄華施用による土壌酸度の低下の影響を少なくするために消石灰を併用すると硫黄華単用よりも赤心症の発生が多く, 肥大根の硫黄含有率は低くなる傾向にあった. このことから, 硫酸カルシウムによる赤心症の抑制作用はカルシウムではなく硫黄によるものであると考えられる.赤心症の発生が抑制された硫黄華施用区では肥大根のポリフェノール含量が減少し, ポリフェノール酸化酵素活性が低下した.

The potential effect of preharvest environmental variation on the postharvest behaviour of apples (Malus domestica Borkh.) was assessed for ‘Cripps Pink’ variety apples grown in four different agroclimatic locations along the irrigated valley of Central Chile (Llancanao, Malloa, El Radal and El Parrón). The flesh firmness, total soluble solids (TSS), skin colour, internal ethylene concentration (IEC), internal browning (IB) and index of absorbance difference (IAD) were assessed in apples that had been stored at 0.5 and 2°C for 4 and 6 months and correlated with environmental parameters prior to harvest (February). There was notable variation in the IAD, percentage of red-coloured skin, TSS, firmness and IEC among the orchards at both storage temperatures, and both radial and diffuse IB were identified. Further analysis showed that the preharvest environmental conditions were correlated with the evaluated parameters, with five significant correlations (P < 0.05) being found and 63 of the 120 correlations examined having r values above 0.5. These findings indicate that preharvest environmental conditions affected fruit parameters during storage, which has implications under climate change.

Identification of physiological changes and key metabolites coincident with postharvest internal browning of pineapple (Ananas comosus L.) fruit

A combination of hot air and methyl jasmonate vapor treatment alleviates chilling injury of peach fruit

In this study, physical and chemical changes were investigated during 6 months storage of cranberry nectar at different temperatures (4, 22, 30 and 40 °C). The water-soluble dry matter value remained approximately the same throughout storage. The decrease in the pH value during the preservation of the nectars increased the titration acidity. Total phenolic substance and antioxidant activity values decreased at high storage temperature, but there was no regular change during the storage period. Sugar, water-soluble vitamin and trans-resveratrol analyzes were performed by high performance liquid chromatography (HPLC). During storage at high temperatures, a decrease in a value and an increase in b values were observed in cranberry nectar. The least change in color values was measured in cranberry nectars stored at 4℃. While sucrose was the dominant sugar in cranberry nectars at the beginning of storage, the amount of glucose and fructose increased at the end of storage. The ascorbic acid content of cranberry nectar was detected to be high. While the initial value of trans-resveratrol in cranberry nectar was 0.9518 mg/L, it decreased to 0.6478 mg/L at 40 °C at 6 months. The least loss in trans-resveratrol content was seen in cranberry nectars stored at 4 °C and 22 °C. A decrease in the bioactive components of cranberry nectar was observed during storage. Total phenolic substance content decreased as storage temperature increased. Although the antioxidant activity value did not show a change depending on the storage time, it decreased due to the increase in temperature. The highest physical and chemical change during storage occurred at 40°C.

Effect of different temperatures on the storage of papaya fruits and respirational activity during storage

Sugar palm fruit is a tropical fresh product which derived from sugar palm plants. Handling and storage of sugar palm fruit is still in the traditional way, and it creates difficulties for broader marketing. Storage air temperature and film packaging greatly affects to various factors of the fresh products damage that can be represented by the change in respiration rate of those produtcs. The aim of this study was to study the effect of storage temperature and plastic film characteristics on the change of the respiration rate of sugar palm fruit during storage period in the MAP. Several treatment combinations including storage temperature and plastic film thickness were investigated in the research. It was found that storage temperature had stronger effect on the respiration rate of sugar palm fruit as compared to the effect of packaging film thickness. The higher storage temperature the longer would the time to reach constant O2 and resulted in the higher respiration rate. Statistical analysis indicated that storage temperature, packaging film thickness, and the interaction of those two factors were significantly affect the respiration rate of the fruit. Arrhenius kinetics could explain the effect of storage temperature on respiration rate of sugar palm fruit.

SummaryThe effects of constant high temperatures of 25 and 307C in comparison with a low temperature storage regime at 2&C were investigated on storability of two bulb onion (Allium cepa L.) cvs. Texas Early Grano and Dorcheh (an Iranian cultivar) under 65–75% relative humidity for a period of 270 days. In both cultivars, sprouting of onion bulb is inhibited at high storage temperatures as a result of significant reduction in the relative growth rate of sprout leaves within the bulbs, compared with low-temperature storage at 2&C treatments in both cultivars, and onions became nearly dormant. Onion cv. Texas Early Grano maintained marketability at temperatures of 25 and 30&C for periods of three and two months, respectively. During the first 3–4 months of storage at these high temperatures there was no significant change in pH, total soluble solid (TSS) and titratable acidity of the bulbs contents, compared with a low temperature of 2&C for both cultivars. However, over longer periods, rotting and desiccation in bulbs increased and cv. Texas Early Grano showed significantly more weight loss and rotting than cv. Dorcheh. The data indicate that weight loss due to desiccation was a major index in onion for the determination of storage potential at high temperatures, and that is varies between cultivars.

Effects of Storage Time and Temperature on Egg Quality in Old Laying Hens