A comparative study of composition and postharvest performance of organically and conventionally grown kiwifruits

Abstract

Postharvest performance of organic and conventional 'Hayward' kiwifruits grown on the same farm in Marysville, California, and harvested at the same maturity stage were compared in this study. Quality parameters monitored included morphological (shape index) and physical (peel characteristics) attributes of the initial samples. Maturity indices (CO 2 and C 2 H 4 production, firmness, color, soluble solids content and acidity) and content of compounds associated with flavor and nutritional quality (minerals, sugars and organic acids, ascorbic acid, total phenolics, and antioxidant activity) were determined at 0, 35, 72, 90 and 120 days of storage at 0• C, and after 1 week of shelf-life simulation at 20• C, after each storage duration. Organically and conventionally grown kiwifruits had similar soluble solids content at harvest, but conventional kiwifruits had a higher firmness and L * value, and a lower hue angle and chromaticity, resulting in a lighter green color when compared with the organic kiwifruits. These differences were maintained for all the storage durations, with the soluble solids content increasing more in conventionally grown kiwifruits. The two production systems resulted in different morphological attributes since organic kiwifruits exhibited a larger total and columella area, smaller flesh area, more spherical shape, and thicker skin compared to conventional kiwifruits. All the main mineral constituents were more concentrated in organic kiwifruits, which also had higher levels of ascorbic acid and total phenol content, resulting in a higher antioxidant activity. Sugars and organic acids composition was not affected by the production system.

Qualidade de laranjas 'Valência' produzidas sob sistemas de cultivo orgânico e convencional

“…Estes resultados da relação SST/ATT estão em conformidade com observações de Amodio et al (2007), que determinaram que quivis 'Hayward' produzidos em pomares convencionais apresentam maior SST após 4 meses de armazenamento em relação aos frutos produzidos em pomares orgânicos, mas não houve diferenças entre os sistemas de cultivo quanto à ATT. Já Lester et al (2007) Prange (1992), os frutos produzidos em sistema de cultivo orgânico apresentaram maior teor de SST e não se diferenciaram entre si quanto à ATT.…”

“…Lester et al (2007) verificaram que os pomelos orgânicos apresentaram maior L que os convencionais, em duas das três épocas avaliadas, e menor C em uma das três épocas, sendo os frutos do sistema orgânico mais luminosos e de coloração menos intensa que os frutos de sistema convencional. Amodio et al (2007) verificaram que quivis 'Hayward' de pomar convencional apresentavam-se mais brilhosos e de coloração menos intensa que os quivis de pomar orgânico. Já Roussos e Gasparatos (2009) não observaram diferenças nas variáveis de cor avaliadas em maçãs cultivadas sob sistemas de cultivo orgânico e convencional.…”

“…Lester et al (2007) observaram que os pomelos de pomar orgânico continham maior teor de vitamina C que os pomelos produzidos em pomar convencional, só não havendo diferenças nos frutos colhidos tardiamente. Amodio et al (2007) também verificaram que quivis provenientes de pomares orgânicos continham mais vitamina C que os de pomares convencionais após 120 dias de armazenamento a 0º C. Worthington (2001) verificou que frutos e vegetais produzidos sob sistema orgânico de cultivo apresentam, em média, 27 % a mais vitamina C que os sob manejo convencional, em um total de 132 comparações. Acerolas produzidas sob manejo orgânico apresentaram quase que o dobro de vitamina C em relação aos frutos produzidos sob manejo convencional, enquanto não houve diferenças em caqui.…”

Impact of Harvesting Time and Length of Cold Storage Period On Physiological and Quality Traits of Four Quince Genotypes (Cydonia Oblonga Mill.)

“…Khoush Ghalb et al (2008) showed that Asian pear at harvesting had large amounts of sucrose that was converted into simple sugars during prolonged storage, which leads to increase of TSS. These metabolic processes coincide with an increase or decrease other compounds, such as acids, soluble pectins, and phenolics (Amodio et al 2007). In current research, TSS values differ among genotypes.…”

The influence of “Hayward” kiwi fruit (Actinidia deliciosa) from organic and conventional cultivations on the content of some trace elements in the rat kidneys and assessment of copper, manganese and zinc bioavailability / Wpływ owoców kiwi “Hayward” (Actinidia deliciosa) z upraw ekologicznej i konwencjonalnej na zawartość niektórych mikroelementów w nerkach szczura i ocena biodostępności manganu, miedzi i cynku

“…"Hayward" kiwifruits originating from ecological cultivations where only natural fertilisers were used were characterised by thicker peel and smaller flesh surface [Amodio et al 2007] and were firmer than kiwi from the conventional cultivations [Hasey et al 1997]. However, Benge et al [2000] revealed that kiwi from conventional cultivations did not differ in firmness but were characterised by a higher content of soluble stable substances.…”