Relative humidity effect on encapsulation properties of coproducts obtained from wet milling of amaranth grain

Abstract

The co-products of the amaranth starch extraction have recently aroused the interest of the industry, mainly due to their functional characteristics. In this paper, the encapsulating efficiencies of starch-enriched fraction (SEF) and native starch (NS) obtained, respectively, by dry or wet milling were studied. The storage humidity effect (11 to 84%, 21 days) on β-carotene retention were evaluated. Significant effects of amaranth protein present in SEF matrix on emulsification and subsequent retention of β-carotene were found. The best encapsulation performance was showed by ball milled starch enriched fraction (SEF-BM) fraction, with up to three times of total β-carotene content in comparison with the NS containing matrices. The glass transition temperature (Tg) of the samples decreased with the increase in relative humidity due to the plasticizing effect of the water. The starch-enriched amaranth fraction showed a high technological potential as an encapsulating agent and its own protein content served as a good emulsifier-stabilizer.

Keywords

• Encapsulating Agent
• β-carotene
• Amaranth Starch
• Amaranth Flour
• Planetary Ball Milling
• Wet milling