Effects of Postharvest Time, Heat Treatment, pH and Filtration on the Limonin Content in Newhall Navel Orange (Citrus sinensis Osbeck cv. Newhall) Juice

Abstract

Delayed bitterness causes severe economic loss in citrus juice industry worldwide, which is mostly due to the formation of limonoid compounds, especially limonin, in juice. In this study, effects of postharvest time of fruits, heat treatment, pH and filtration of juice on limonin content in Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) juice were investigated. Our research indicated for the first time that: (1) limonin content in juice would gradually increase to a maximal level and then remained almost constant thereafter as storage time going on, whereas the maximum constant value (MCV) of limonin content in juice significantly (p < 0.05) decreased with the increment of postharvest time of fruits being juiced; (2) heat treatment and acidification of juice only speeded up the formation of limonin to the maximal level while without changing the MCV of limonin content; (3) the juice after filtration exhibited much lower MCV of limonin content compared with the unfiltered one. These experimental observations might not only provide useful information for the development of new debitterness method for navel orange juice, but also strongly support the acid-promoted delayed bitterness mechanism, suggesting the formation of delayed bitterness might primary due to the acid-promoted rather than the enzyme-catalyzed lactonization of limonoate A-ring lactone (LARL) to produce limonin in juice of navel orange.

Chemical composition, antioxidant, antibacterial, and tyrosinase inhibition activity of extracts from Newhall navel orange (Citrus sinensis Osbeck cv. Newhall) peel

“…Newhall) is the major navel orange cultivar planted in Ganzhou, in east China's Jiangxi province. By the end of 2017, the total planting areas of navel orange (over 90% being Newhall cultivar) in Ganzhou had reached around 103 200 hectares, with an annual output of about 1.24 million tons, making Ganzhou the largest navel orange production area in China . With the consumption of orange pulp, huge amounts of orange peel are left, which account for about 30% of the weight of the whole fruits.…”

“…With the consumption of orange pulp, huge amounts of orange peel are left, which account for about 30% of the weight of the whole fruits. Eating the fresh fruit is the main consumption method for Newhall navel orange at the present time due to the delayed bitterness of its juice, which is primarily caused by the gradual formation of limonin . With the development of technology to control the delayed bitterness, juice production from Newhall navel orange might be achievable in the future.…”

“…By the end of 2017, the total planting areas of navel orange (over 90% being Newhall cultivar) in Ganzhou had reached around 103 200 hectares, with an annual output of about 1.24 million tons, making Ganzhou the largest navel orange production area in China. 1 With the consumption of orange pulp, huge amounts of orange peel are left, which account for about 30% of the weight of the whole fruits. Eating the fresh fruit is the main consumption method for Newhall navel orange at the present time due to the delayed bitterness of its juice, which is primarily caused by the gradual formation of limonin.…”

“…Eating the fresh fruit is the main consumption method for Newhall navel orange at the present time due to the delayed bitterness of its juice, which is primarily caused by the gradual formation of limonin. 1 With the development of technology to control the delayed bitterness, juice production from Newhall navel orange might be achievable in the future. Indeed, Nongfu Spring, a leading water company in China, has recently established a factory in Ganzhou, to produce juice from the Newhall navel orange.…”

Dynamic variation of the phytochemical and volatile compounds in the pericarp of Citrus reticulata ‘‘Chachi’’ (Rutaceae) during 2 years of storage

“…Li et al (2019) have illustrated that the conversion of precursor limonoate A-ring lactone (LARL) to limonin is primarily related to limonoid D-ring lactone hydrolase (LLH). The reduction of limonin during storage may be due to the change of LARL and LLH, and this change could reduce the bitterness of medicinal herb (Zhang et al, 2018). Evidently, ferulic acid was extremely low in content, and it could not be determined accurately at the beginning, but it increased significantly (p < 0.05) to 0.07 ± 0.01, 0.07 ± 0.01, and 0.07 ± 0.02 mg g −1 in CRCP-G1, CRCP-G2, CRCP-G3 after storage, respectively.…”