Stability of Vitamins during Extrusion

Abstract

Vitamins (fat and water soluble) are vital food ingredients for healthy living, required by our bodies for normal metabolism. These are present in most natural food in small quantities, but when we process food through thermal processing methods (especially extrusion) a reasonable amount of the present vitamins are lost. During extrusion, factors like barrel temperature, screw rpm, moisture of ingredients, die diameter, and throughput affect the retention of vitamins in food and feed. The vitamins most sensitive to the extrusion process are vitamin A and vitamin E from fat-soluble vitamins, and vitamin C, B(1), and folic acid from water-soluble vitamins. The other vitamins of the B group, such as B(2), B(6), B(12), niacin, Ca-pantothenate, and biotin, are stable. Vitamin E itself or in its complex form is quite unstable during processing and even in storage of extruded food. Ascorbic acid directly added or coated with fat and then added to feed during extrusion is also very unstable. Vitamins A, C, D, and E are also sensitive to oxidation, so these vitamins have minimum retention during storage of extruded food.

Thermal sterilization affects the content of selected compounds in diets for laboratory animals

“…In general, our recent results (Taciak et al, 2011) on the effects of autoclaving on vitamin B 1 and Ca pantothenate are inconsistent with the conclusions of Riaz et al (2009), who designated vitamin B 1 as sensitive and Ca pantothenate as heat stable during extrusion.…”

“…In Taciak et al (2011), the retention of thiamine reached 73% only in a premix autoclaved at 105°C for 10 min, whereas it dropped to 15% and 17% in the premix autoclaved at 121°C for 20 min and 134°C for 10 min, respectively. Also in a study reported by Riaz et al (2009), the effect of temperature on thiamine stability seems to be greater than found in the recent study: high retention of thiamine in feed extruded at 91°C to 95°C declined to 50% when the temperature was raised the range of 141°C to 145°C. According to data presented by Coelho (2002), the destructive effect of temperature on vitamin B 1 depends on its chemical form and is greater on thiamine HCl than on thiamine mononitrate.…”

“…In view of the lack of available data on the vitamin losses in autoclaved feeds, we compared our results with the effects of similar temperature ranges applied during extrusion and pelleting. Such comparisons are not, however, fully valid since physical factors such as screw speed, die diameter, or throughput also affect vitamin deterioration in differently processed feeds (Riaz et al, 2009).…”

“…Losses of particular vitamins in differently processed feeds are variable -in extruded feeds they may vary from 5% for choline to 85% for vitamin C (Riaz et al, 2009). Attempts have been made to enhance their retention by the use of protective technologies and more stable chemical forms (Coelho, 2002).…”

Critical Review—Electrochemical Properties of 13 Vitamins: A Critical Review and Assessment

“…[13][14][15][16][17][18][19] Vitamins may be unstable to heat and light as well as exposure to acid, alkali, air, and moisture. Review of four References 13-16 flagged vitamins unstable in acid, alkali, and on exposure to air (oxygen) and moisture.…”