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Modified atmosphere packaging (MAP) and refrigeration of fruits and vegetables are used to extend their shelf life. The hypothesis of this study is that quality attributes of avocados stored in MAP at 8 °C can be preserved for a longer period, compared to room temperature (RT) or refrigeration (REF) storage; however, during post-storage ripening (PSR), these quality variables approach those of refrigeration or room temperature in a brief time. The objective of this research was to evaluate quality variables in avocado (Persea americana Mill.) cv. "Hass" during storage in MAP at 8 °C and PSR at 21 °C and contrast them to those obtained during storage at RT or REF. Fruits at physiological maturity and MAP bags were used. A completely randomized design was used; factors were type of storage (RT 21 °C, REF 8 °C, and MAP 8 °C), storage time (0, 8, 16, 24, and 32 d), and PSR time at 21 °C (0, 2, 4, and 6 d). Quality variables were firmness (penetration force), total colour difference (AE) in exocarp and mesocarp (colorimeter), pH (potentiometry), and total soluble solids (TSS, refractometry). Avocados stored in MAP retained firmness, which was higher compared to REF and RT during the storage period. Firmness retention for avocados at RT, REF, and MAP, at day 16, was 5.7, 32.6, and 87.2 %, and at day 32, it was 0 (no reading), 9.5, and 78.2 %, respectively. Total colour difference in exocarp and mesocarp, pH, and TSS ranged from 3.8 to 25.6, 3.2 to 20.3, 6.7 to 7.1, and 5.3 to 7.7 °Brix, respectively. During the storage period, fruits stored at MAP showed a firmness, AE of exocarp and mesocarp similar to those of fresh fruit. Type of storage showed no effect on pH and TSS, during the storage period. Modified atmosphere at 8 °C allows to extend the shelf life of "Hass" avocado for a period twice as long as that at room temperature, based on the changes in firmness and colour are reduced, properties that are important quality benchmarks. [ABSTRACT FROM AUTHOR]

During the harvest, processing, and distribution of avocado (Persea americana Mill.), a large amount of waste (peel, seed, and pulp) is produced, which has proven to have antioxidant properties and this by-product might be used as input within the food production chain. This study evaluates the lipid oxidation, antioxidant capacity and phenolic compounds of two pastes made with avocado by-products (with seed: PS and without seed: PWS) during 60 d stored under refrigeration. On the results obtained, an analysis of variance (ANOVA) was performed, followed by the Tukey's test (p ≤ 0.05). The lipid oxidation was controlled in both pastes and was even reduced during storage. In the PS, the antioxidant capacity declined, although it remained high and very similar to the PWS towards the end of the storage. The concentration of phenolic acids increased during most of the time of storage. Although PWS displayed better results with two of the analyses performed, both pastes were considered to have important antioxidant characteristics, which remained during the refrigerated storage. Due to this, its potential use in the production of foods is inferred, particularly for animals such as cattle, pigs, in aquaculture, or even in the cosmetics industry. [ABSTRACT FROM AUTHOR]

Refrigeration and modified atmosphere packaging (MAP) are useful technologies to preserve and extend the shelf life of fruit and vegetables. The packaging industry aims to permanently develop technologies that provide suitable conditions for the commercialization of fruit and vegetables. Due to the market demands, packages were developed to protect fresh products from quality loss and to prolong shelf life. MAP is not always used for horticultural products in Mexico. There are few cases where packages are designed for a specific fruit. Sometimes, the same package is used for different fruit; therefore, there is no adequate control of the gas concentration during storage, causing a faster deterioration. The objective of this research was to simulate the O2 and CO2 concentrations of "Hass" avocado (Persea americana Mill.) stored in a MAP with different O2 and CO2 permeabilities, based on the non-stationary state mass balances for the gas concentrations and the enzymatic kinetics for O2 consumption and CO2 production rates. A closed system and inhibition models were used to determine the respiratory behavior, and the correspondent kinetic parameters were obtained through a regression analysis. The O2 and CO2 concentrations inside a MAP in function of time were satisfactorily (R2>0.97) simulated at 8±1 °C using a competitive inhibition model. Through simulation, different permeabilities were tested to ensure lower O2 and higher CO2 concentrations levels inside the MAP. With the estimated O2 (2.9´10-5 mL cm cm-2 h-1 cmHg-1) and CO2 (4.1´10-5 mL cm cm-2 h-1 cmHg-1) permeabilities, the gas concentrations inside the package were simulated for the system to reach stable concentrations of 10.0 and 9.5 mol% for O2 and CO2 after 240 h of storage. These permeabilities could improve the internal atmosphere and extend the "Hass" avocado shelf life when stored under MAP at 8±1 °C. [ABSTRACT FROM AUTHOR]