EFFECTS OF BROMELAIN ENZYMATIC PROTEOLISIS ON SOME RHEOLOGICAL AND TECHNOLOGICAL PROPERTIES OF BEEF

R.M. Radu-Rusu, Roxana Raţu, Olga Sorocopud

Abstract
    The research focused on the effect induced by two enzymatic proteolytic solutions based on bromelain on certain rheological and technological traits of beef. There were studied samples from Longissimus dorsi muscle, non-enzymatically treated (control, NET group) or treated with natural originated bromelain solution (ABE group, solution 50%, triturated pineapple and filtered liquid phase, mixed with distilled water 1:1) and with bromelain food additive (BFA group, Bromelain powder 2000 GDU/g, solution 1%). There have been run 120 analytical tests (3 experimental factors x 4 reasoning criteria x 10 repetitions). The results indicated decreased Adams consistency, compared to control group, by 72.7% (ABE) – 90.9% (BFA) and reduced shear force by 16.56% (ABE, 39.30N) – 23.31% (BFA, 36.12N), vs. NET samples (47,10N). Water holding capacity was 13.70-20.79% decreased while the cooking yield was 10.68-12.70%, consequently to the bromelain proteolysis. Although textural improvement of the meat has been noticed, assessed instrumentally through tenderness descriptors, the proteolytic treatment induced, however, loss of beef technological properties. It remains to study to what extent the usage of bromelain, as proteolysis agent, could efficiently improve meat tenderness, without affecting significantly its technological or sensorial properties, knowing that bromelain could impregnate to meat, in certain situations, a slightly bitter and astringent taste, not accepted by some consumers.

Key words: beef, proteolysis, bromelain, Adams consistency, shear force, water holding capacity, cooking yield