Data/hora: 17/06/2024 07:17:17

Biblioteca(s): | Embrapa Mandioca e Fruticultura.
Data corrente: | 08/07/2013
Data da última atualização: | 19/05/2023
Autoria: | PEREIRA, M. E. C.; TIEMAN, D. M.; SARGENT, S. A.; KLEE, H. J.; HUBER, D. J.
Afiliação: | MARCIO EDUARDO CANTO PEREIRA, CNPMF; DENISE M. TIEMAN, University of Florida; STEVEN A. SARGENT, University of Florida; HARRY J. KLEE, University of Florida; DONALD J. HUBER, University of Florida.
Título: | Volatile profiles of ripening West Indian and Guatemalan-West Indian avocado cultivars as affected by aqueous 1-methylcyclopropene.
Ano de publicação: | 2013
Fonte/Imprenta: | Postharvest Biology and Technology, v.80, p.37-46, 2013.
Idioma: | Português
Conteúdo: | Separate experiments were conducted with three major commercial avocado (Persea americana Mill.) cultivars grown in Florida: Simmonds (early-season, West Indian race); Booth 7 (mid-season, Guatemalan-West Indian hybrid); and Monroe (late-season, Guatemalan-West Indian hybrid). Fruit were harvested at preclimacteric stage and left untreated (Control) or treated 24 h after harvest with aqueous 1-methylcyclopropene (1-MCP) at 1.39 (treatment M1) or 2.77 mol L1 a.i. (treatment M2) (75 or 150 g L1) for 1 min at 20 C. Whole fruit ripening was monitored at 20 C/92% 3% R.H. and based on whole fruit firmness, respiration and ethylene evolution. Fruit volatiles were assessed at preclimacteric (24 h after harvest), mid-ripe (half of initial fruit firmness) and ripe maturity stages, from 100 g of chopped pulp using a purge and trap system. Untreated, firmer fruit Monroe (268 N at harvest) ripened within 12 d of harvest while softer fruit Simmonds (118 N) ripened within only 6 d. 1-MCP treatment extended ripening time from 33% (M1) to 83% (M2). All fruit softened normally, indicating the potential benefits of aqueous 1-MCP as a postharvest treatment for avocado when applied at these concentrations. Volatile profiles differed among the three cultivars with several compounds detected in only one cultivar, results that may contribute to a potential identification of the origin of the cultivar based on fruit volatile composition. The West Indian cultivar Simmonds had much higher emission of hexanal (preclimacteric fruit) and cis-3-hexenal and cis-3-hexen-1-ol (ripe fruit) than the uatemalan-West Indian hybrids Booth 7 and Monroe. On the other hand, these latter hybrids had much higher levels of alkanes than Simmonds. Treatment with 1-MCP increased emissions of alkanes during ripening of Booth 7 and Monroe. Total volatiles of avocado decreased during ripening mainly due to the significant reduction of sesquiterpenes, the main group of volatiles in all cultivars at harvest (Simmonds, 53%; Booth 7, 78%; Monroe, 66%). -Caryophyllene was the major compound at harvest, but decreased to less than 2% in ripe fruit, at which point most sesquiterpenes were not detected. Among the 10 sesquiterpenes commonly found in the avocado cultivars in this study, only -Copaene had significantly higher emissions in mid-ripe fruit treated with the higher concentration of 1-MCP (2.77 mol L1 a.i.), suggesting that ethylene participates in the regulation of this sesquiterpene.
Thesagro: | Abacate.
Thesaurus Nal: | Avocados.
Categoria do assunto: | --
Registro original: | Embrapa Mandioca e Fruticultura (CNPMF)
Exemplares: | CNPMF - (29472-1) - UPC - AP - DD - Publicação digital -  -  - DIS