ABSTRACT
We have identified the best harvesting periods, related to higher bioactive compound content and post-harvest quality, for minimally processed sweet potatoes with orange pulp and cream pulp. Quality loss in minimally processed sweet potatoes occurred due to browning in cv. Mãe de Familia and ESAM1 and to whitening in cv. Paraná. Both Mãe de Família and ESAM1 presented higher peroxidase and polyphenol oxidase activities at 120 days, and cv. Paraná contained high levels of provitamin A. ß-carotene was the major carotenoid (up to 99%) in orange pulp. All cultivars harvested at 150 and 180 days and minimally processed showed the best visual quality, the highest bioactive compound content, and no microbial infection. Delaying the harvest also increase the antioxidant activity in orange roots, which was associated with a high content of carotenoids and phenolic compounds, resulting in an increase in the nutritional quality of the product. PRACTICAL APPLICATIONS: Postharvest techniques can improve the visual and phytochemical quality of vegetables and extend their shelf life. The present research provides the best harvesting periods for minimally processed cream and orange sweet potato roots with higher postharvest qualities. Delaying the harvest resulted in a product with better visual quality, higher levels of bioactive compounds, which are highly beneficial to health, for example, ß-carotene, and no microbiological contamination. Our results may contribute to improvements in the current knowledge about harvesting times for sweet potato growers who aim to produce high quality, minimally processed products with a longer shelf life.
Subject(s)
Ipomoea batatas , Solanum tuberosum , Antioxidants , Carotenoids , beta CaroteneABSTRACT
Fresh cut beetroot showed low shelf life, even under refrigeration, and the main quality depreciative factor is the superficial discoloration (white blush) that depreciates the quality of the product. The objective of this research was to verify the effect of three cut types on quality of the minimally processed beetroot during cold storage. The cut types used were slice, cube and shred. After processing, the beetroots were stored at 5°C during ten days and the evaluations were carried out each two days. Sliced beetroots showed higher respiratory rate and higher losses of betalains and soluble solids during cold storage. Visual quality of minimally processed beetroot was preserved up to four days of storage in both cut type. The main factor that has caused loss of quality of this vegetable was the incidence of white blush. It can be concluded that the beet minimally processed in slices or cube presents conservation of, at the most 4 days to 5°C, while minimally processed in shred it presents 6 days of conservation.
Beterrabas minimamente processadas apresentam vida de prateira curta, mesmo sob refrigeração, devido à descoloração superficial que deprecia a qualidade do produto. O objetivo do trabalho foi verificar o efeito de três tipos de corte em beterraba minimamente avaliando sua qualidade durante a conservação refrigerada. Os cortes utilizados foram: fatia, cubo e retalho. Após o processamento as beterrabas foram armazenadas a 5°C e as avaliações sendo realizadas durante dez dias a cada dois dias. Beterrabas em fatias apresentaram maior respiração e maiores perdas dos pigmentos betalaínas e de sólidos solúveis durante o armazenamento. Através de análise sensorial, verificou-se que a qualidade visual do produto foi mantida por até quatro dias, independente do tipo de corte. O fator que mais depreciou a qualidade de beterraba minimamente processada foi a perda de coloração das raízes (esbranquiçamento). Pode-se concluir que a beterraba minimamente processada em fatias ou cubo apresenta conservação de, no máximo 4 dias, a 5°C, enquanto minimamente processada em retalho apresenta 6 dias de conservação.
ABSTRACT
Fresh cut beetroot showed low shelf life, even under refrigeration, and the main quality depreciative factor is the superficial discoloration (white blush) that depreciates the quality of the product. The objective of this research was to verify the effect of three cut types on quality of the minimally processed beetroot during cold storage. The cut types used were slice, cube and shred. After processing, the beetroots were stored at 5°C during ten days and the evaluations were carried out each two days. Sliced beetroots showed higher respiratory rate and higher losses of betalains and soluble solids during cold storage. Visual quality of minimally processed beetroot was preserved up to four days of storage in both cut type. The main factor that has caused loss of quality of this vegetable was the incidence of white blush. It can be concluded that the beet minimally processed in slices or cube presents conservation of, at the most 4 days to 5°C, while minimally processed in shred it presents 6 days of conservation.
Beterrabas minimamente processadas apresentam vida de prateira curta, mesmo sob refrigeração, devido à descoloração superficial que deprecia a qualidade do produto. O objetivo do trabalho foi verificar o efeito de três tipos de corte em beterraba minimamente avaliando sua qualidade durante a conservação refrigerada. Os cortes utilizados foram: fatia, cubo e retalho. Após o processamento as beterrabas foram armazenadas a 5°C e as avaliações sendo realizadas durante dez dias a cada dois dias. Beterrabas em fatias apresentaram maior respiração e maiores perdas dos pigmentos betalaínas e de sólidos solúveis durante o armazenamento. Através de análise sensorial, verificou-se que a qualidade visual do produto foi mantida por até quatro dias, independente do tipo de corte. O fator que mais depreciou a qualidade de beterraba minimamente processada foi a perda de coloração das raízes (esbranquiçamento). Pode-se concluir que a beterraba minimamente processada em fatias ou cubo apresenta conservação de, no máximo 4 dias, a 5°C, enquanto minimamente processada em retalho apresenta 6 dias de conservação.