Use of iPergularia tomentosa/iPlant Enzymatic Coagulant System in Fresh Cheese-Making

摘要

Introduction: Pergularia tomentosa is a saharan spontaneous plant belonging to Asclepiadacea family. It has several medicinal properties and uses in the human food as an auxiliary in cheese-making. The purpose of this study is the extraction of the coagulant enzymatic system (C.E.S) from the plant dried leaves and its use in the preparation of fresh cheese. Materials & Methods: The determination of the coagulant activity was carried out on a skimmed milk powder by Berridge’s method. Cow’s milk used for coagulant strength determination and cheese-making. Proteolytic activity. The chemical determinations of raw milk were carried out according to AFNOR analysis methods. A descriptive sensory evaluation was performed to determine the organoleptic properties of the produced cheese. The proteolytic activity was determined by measuring the aspartyl-protease units. Results: The main results of the physico-chemical characterization show that its coagulant activity (R.U mL-1) was 97.19 ± 4.67, coagulant strength (SU) was 230.05 ± 0.37, proteolytic activity (μg·mL-1) was 0.33 ± 0.04 and coagulant activity/proteolytic activity ratio was 294.51. For the cheese made, it has presented the following results as % (g/100g): titrable acidity 0.80 ± 0.005, total dry extract 30.48 ± 1.490, fat 2.32 ± 0.02, fresh yield 11.5 ± 0.09, dry yield 30.06 ± 0.05. Moreover, sensory analysis results showed that fresh cheese prepared from Pergularia tomentosa dried leaves diluted enzymatic extract filtrate was characterized by whitish color, smooth texture, with acceptable and satisfying lactic taste. Conclusion: The plant enzymatic system studied could be added to the list of plant rennet substitutes and, thus, contributes to the manufacture of enzymatic coagulation cheese.