Yield maximization in sous vide cooked beef (Semitendinosus muscle)

Abstract

The temperature and cooking time used in meat processing are factors that interfere with its yield. The sous vide system associates pasteurization of up to 95 °C of vacuum packed foods with the control of the processing and storage conditions. This system can provide an increase in the yield of processed meat. The objectives of the present study were to maximize the processing yield of beef slices (Semitendinosus muscle) using the sous vide system, and to assess the effects of cooking time and temperature on the water extracted under pressure, and on the pH, colour and shear strength. A central composite rotational design for two independent variables (temperature and cooking time) was used, totalizing eleven treatments. The meat processing yields ranged from 60.70 to 75.05%, and maximization was achieved at the lower temperatures (around 65 °C) with cooking times around zero (after reaching the required temperature). Under these conditions higher percentages of liquid were extracted under pressure after cooking, since they favoured water retention in the meat. The variation in cooking temperature had a greater impact on the yield than that of time. The pH of the processed meat ranged from 5.73 to 6.49, showing no apparent association with the cooking conditions. Cooking at intermediate temperatures resulted in meats with higher values for L* and lower values for a*. All the meat samples showed low shear strength values (between 1.19 and 2.31 kgf). The greater dissolution of the collagen during the prolonged cooking times must have contributed to the lower shear strength values under these conditions.

Keywords:
Vacuum cooking; Semitendinosus muscle; Yield; Shear strength; Colour