Nghiên cứu ảnh hưởng của thời gian sấy thứ cấp đến chất lượng thịt rẻo thanh cá ngừ cắt viên sấy đông khô

Abstract

Freeze-drying of tuna meat fragments (Scombridae) was carried out to assess their physical and sensory characteristics, with the goal of developing products for use in instant soups and snacks. To optimize the drying time, the dehydration kinetics and drying yield were investigated. The results showed that tuna samples cut into 0.5 × 0.5 cm blocks and subjected to different freeze-drying programs all achieved moisture content ≤ 5% and water activity (aw) ≤ 0.155. Color differences were observed, with an average ΔE* of 5.15. The L* values ranged from 37.43 ± 9.5 to 59.90 ± 6.65; a* values ranged from 9.36 ± 1.22 to 14.68 ± 1.35; and b* values from 9.84 ± 1.46 to 16.22 ± 1.10. The hardness of the dried products ranged from 5.94 N to 12.86 N. Processing yield varied between 26% and 28.4%. Shrinkage was ≤ 12%, while the rehydration capacity of the freeze-dried product reached 188.8% within 10 seconds.

Key words: freeze-dried, lyophilization, dried fish, yellowfin tuna