Sugar Tech

, Volume 20, Issue 3, pp 235–251 | Cite as

Preliminary Study on the Use of Inexpensive, Unsaturated Vegetable Oils as Surface Sealants in the Long- and Short-Term Storage of Syrup Feedstocks from Sweet Sorghum

  • Gillian Eggleston
  • Stephanie Boone
  • Alexa Triplett
  • Matthew Heckemeyer
  • Randall Powell
  • Maureen Wright
Review Article


For large-scale manufacture of biofuels and bioproducts from sweet sorghum (Sorghum bicolor L. Moench) biomass feedstocks, the long-term storage of 65 Brix (% dissolved solids) syrups is urgently needed for year-round supply and operation, efficient transport, and acceptable end-product yields. Shorter-term storage of lower Brix syrups is also required for direct fermentation. Three unsaturated, inexpensive, and readily available vegetable oils were preliminary evaluated as surface sealants (0–1.7 cm-deep layers) on stored 65 Brix sweet sorghum syrups at 25 °C. Compared to no sealant, soy bean, canola, and sunflower oil sealants preserved the 65 Brix syrups for up to 1 year. There was generally a strong surface oil layer effect, with 1.7 cm-deep layers providing the most significant (P < 0.05) protection. Soy bean oil (up to 0.5 cm) did not preserve 28 Brix syrups against severe microbial deterioration over 7 days of storage. More replicated studies are now needed to validate the results.


Sweet sorghum Bioproducts Syrup feedstocks Storage stability Surface sealants Vegetable oils 



The authors thank Dr. Michael Dowd of USDA-ARS-SRRC in New Orleans for undertaking the oil analyses experiments. Mention of trade names or commercial products in this article is solely for the purpose of providing specific information and does not imply recommendation or endorsement by the US Department of Agriculture. USDA is an equal opportunity provider and employer.

Compliance with Ethical Standards

Conflict of interest

The authors declare that they have no conflict of interest.


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Copyright information

© Society for Sugar Research &#38; Promotion 2017

Authors and Affiliations

  1. 1.USDA-ARS Southern Regional Research CenterNew OrleansUSA
  2. 2.Heckemeyer MillSikestonUSA
  3. 3.Delta BioRenewables LLCMemphisUSA

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