NomenclatureA, B, C, K, k1, k2, z = models' constants; aw = water activity; HST = isosteric heat of sorption (kJ mol−1); L*, a*, b* = color features; Meq = equilibrium moisture content (g of water g of dry matter−1); N = number of data; p = number of constants P = relative percent error (%); PTFE = polytetrafluoroethylene; R = universal constant of gases (8.314 × 10−3 kJ mol−1 K−1); R2 = coefficient of determination; SE = standard error; xm = monolayer moisture content (g of water g of dry matter−1); Y and Ŷ are the experimental equilibrium moisture content and the calculated equilibrium moisture content, respectively.
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ORIGINAL ARTICLE
Effects of environmental conditions on characteristics of annatto seed by-product
Article first published online: 21 DEC 2012
DOI: 10.1111/qas.12003
© 2012 Blackwell Publishing Ltd
Additional Information
How to Cite
, (2012). Effects of environmental conditions on characteristics of annatto seed by-product. Quality Assurance and Safety of Crops & Foods, 4, e20–e28, 4:5, 20–28.
Publication History
- Issue published online: 21 DEC 2012
- Article first published online: 21 DEC 2012
- Manuscript Accepted: 1 JUN 2012
- Manuscript Revised: 15 MAY 2012
- Manuscript Received: 31 JAN 2012
- Abstract
- Article
- References
- Cited By
Keywords:
- Bixa orellana;
- bixin;
- by-product;
- color;
- isotherm
Abstract
Introduction
The processing of annatto seeds yields a low-cost by-product known as annatto seed by-product. Due to its remarkable bixin levels, which is a natural antioxidant, the annatto seed by-product could be used in animal feed supplementation. As a low-moisture product, it is important to know information about hygroscopic behavior, changes during storage, package selection and drying equipment design.
Objectives
The annatto seed by-product's hygroscopic behavior was studied at 25 °C and 35 °C by using saturated salt solutions and the static method.
Methods
During storage with different relative air humidity, the annatto seed by-product's isosteric heat of sorption, bixin content and instrumental color parameters were evaluated.
Results
The isotherms exhibited type III behavior and the Kühn model properly fitted the annatto seed by-product's equilibrium moisture data. Above 75% air relative humidity, agglomeration, darkening and fungal development were observed. The isosteric heat of sorption decreased with an increase in moisture content.
Conclusion
Once the equilibrium was established, bixin losses (approximately 43% of the content) and color changes were more prominent at 35 °C, especially under 68% relative humidity.