Assessment of Green Tuna: Determining Trimethylamine Oxide and its Distribution in Tuna Muscles

Abstract

SUMMARY– In order to assess green meat of tuna in preparation for canning, it is necessary to determine the trimethylamine oxide (TMAO) content of the raw meat.A simple and rapid TMAO determination method combined with a reduction method, which converts TMAO to trimethylamine (TMA), was developed. Using this method, the distribution of TMAO content in the muscles of yellowfin tuna was investigated to determine the most suitable sampling portion of the fish.A recommended practical method of sampling and determining TMAO for assessing green tuna is presented.

Effects of thermal processing and various chemical substances on formaldehyde and dimethylamine formation in squid Dosidicus gigas

“…TMA was determined by the picrate method of Conway and Byrne 17. TMAO was determined by reducing it to TMA as described by Yamagata et al 18 with slight modification. Briefly, 1 mL of squid or gadoid fish extract was treated with 0.5 mL of 10 g L −1 TiCl 3 at 80 °C for 90 s to convert TMAO to TMA.…”

Banana Shrimp, Penaeus merguiensis, Quality Changes During Iced and Frozen Storage

“…The TMAO was determined as TMAO-N (mg/lOOg) by first reducing the TMAO to TMA using TiCl,, giving a total TMA value. The total TMA was then determined by the microdiffusion method (Yamagata et al, 1969). The amount of TMAO was calculated by subtracting the TMA present from total TMA.…”

Procedures for the Efficient Washing of Minced Whiting (Merluccius productus) Flesh for Surimi Production

“…The nitrogen content of solutions was determined using a semi-micro Kjeldahl procedure (AOAC, 1984). TMAO was determined by using a modification of the procedure of Yamagata et al (1969), involving the reduction of TMAO to TMA: TCA extract (2.0 mL) was transferred to a screw-top culture tube with a Teflon cap and 1.0 mLof 1.0% titanium chloride (J.T. Baker Chemical Co., Phillipsburg, NJ) solution was added.…”