Library

feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 43 (1978), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Research is described for the extraction of pectin from lime and lemon peel with nitric acid. Temperature and time were varied while extraction acidity remained constant at pH 1.6. For those extraction conditions that resulted in maximum jelly units, yield of pectin as alcohol precipitate, jelly grade and yield as 150 grade pectin were tabulated. Yields of pectin from lemon peel decreased (6.49% in July to 2.55% in November) with increasing fruit maturity. Comparative data were also obtained for pectins extracted from commercially leached peel and the corresponding rotary dried peel. Loss due to drying peel was from 7.7–10.6% in yield of 150 grade pectin.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 43 (1978), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Samples of approximately 350 kg of commercially leached lime and lemon peel were dried in a pilot plant direct fired rotary dryer with inlet air temperatures of 370, 425 and 535°C, yielding dried pectin pomace with a final moisture content of 15–20, 8–12 and 3–7%, respectively. Pectin was extracted from laboratory leached, undried peel, each of the above dried samples, and commercially leached and dried samples. From fresh peel leached in the laboratory, we found a 65.6 and 55.9% yield of 150 grade pectin on a dry weight basis for lime and lemon, respectively. Drying lemon peel to final moistures of 15–20, 8–12 and 3–7% resulted in yields of 41.1, 41.1 and 25%, respectively. Dehydration of lime peel to 3–7% moisture decreased the yield to 37%. Similar losses were found in commercially dried pectin pomace. A separate experiment was conducted to evaluate the effect of drying on pectin yield from fresh, unleached lemon peel. Unleached peel was successfully dried by mixing 1 part unleached peel with 2.5 parts of dry leached peel. There was a slight loss in the percentage yield of pectin 23.3 and 21.8, but not much change in the jelly grade 230 and 232 between the dry leached and dry unleached peel, respectively.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 41 (1976), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: The necessary pasteurization temperature, F and z values for pectinesterase inactivation were developed for three varieties of orange juices and one grapefruit juice. Since common commercial practice involves blending various orange varieties, the recommended conditions are those for the most heat resistant variety. For an FT=1.0 min, the recommended processes are T = 194°F with z = 12.2 for orange juice and T = 186°F with z = 9.3 for grapefruit juice.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 27 (1962), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Pectinesterase activity, 3 pectic fractions, and other characteristics were determined periodically on 5 component parts of Valencia oranges during a 7-month maturation cycle for 2 seasons. Usually, PE activity for peel, membrane, and juice sacs was least in December, when the Brix/acid ratio was low, and highest in June, when this ratio was greatest. The order of component parts for PE in most cases, from highest to lowest activity, was juice sacs, membrane, peel, seeds, and juice. Water-soluble pectin generally remained constant in peel and juice sacs, increased slightly and then remained constant in the membrane, and was irregular throughout the cycle in the seeds. The trend of ammonium-oxalate-soluble pectin in the components was to increase during maturation. Protopectin in the component parts usually increased to a peak and then gradually decreased for the remainder of the season, except that protopectin in the juice sacs decreased throughout the sampling period. In this component, protopectin evidently was at its maximum by the first picking in December. Total pectin remained constant in the juice and seeds, and slowly declined in the other 3 components with maturation. Membrane contained the highest source of protopectin and total pectin throughout the season.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 18 (1953), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 33 (1968), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: SUMMARY— Exposure of citrus fruits to gamma radiation at doses of 150 and 300 krad increased the water- and oxalate-soluble pectins and decreased the protopectin in component parts of Valencia oranges and Duncan grapefruit. The quantities of water-soluble pectin and protopectin in the peel and membrane were affected the most by irradiation. Degradation of the pectins as measured by jelly grade increased in all components of the irradiated fruits. The greatest decrease in jelly grade occurred in the March samples when the Brix/acid ratio was least. Methoxyl contents of the pectins from the peel of oranges and grapefruit decreased, while this characteristic decreased only slightly in pectins from the membrane of irradiated fruits. Pectinesterase activity in the peel of both oranges and grapefruit decreased with increased dosages, while the activity in the membrane of both fruits increased.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Journal of food science 29 (1964), S. 0 
    ISSN: 1750-3841
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Process Engineering, Biotechnology, Nutrition Technology
    Notes: Pectinesterase activity, 3 pectic fractions, and other characteristics were determined periodically on 5 component parts of Pineapple oranges during a 9.month maturation cycle for 2 seasons. Generally, PE activity was greatest in the peel, membrane, and juice sacs in March, April, and May, when the Brix/acid ratio was highest. However, the activity varied in similar components for like months during the 2 seasons. The order of component parts for PE in most cases, from highest to lowest activity, was juice sacs, membrane, peel, seeds, and juice. Total PE in the average whole orange attained maximum activity in March and April. Over 52% of the activity present was found in the juice sacs, which represented about 22.5% of the whole fruit. Water-soluble pectin increased slightly in the peel and membrane, remained somewhat irregular in the juice sacs, and decreased to a constant level in the seeds throughout the growing season. Ammonium-oxalate-soluble pectin in the peel decreased slightly, and in the other components was either irregular or increased slightly, during maturation. Quantity of protopectin was greatest in the membrane and generally decreased toward the end of the sampling period in the various components. Total pectin and weight of the average whole orange was greater in the 1961–62 season than in the preceding season.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    ISSN: 1618-2650
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...