Effect of chemical preservatives on the quality of refrigerated apple cubes in orange juice packaged in different plastic films

ANDRÉS, SILVINA CECILIA; GIANNUZZI, LEDA; ZARITZKY, NOEMÍ E.

Puebla, México

Congreso; Eighth International Congress on Engineering and Food (ICEF 8); 2000

IAEF, International Association for Engineering and Food

Demand from consumers is increasing for ready-to-use fruits and vegetables; these products deteriorate during storage by physiological aging, discoloration at the cut surfaces and microbial spoilage. Discoloration involves the enzymatic polymerization of phenolic compounds; it is retarded by low temperature storage, low levels of oxygen and the addition of antioxidants. The objective of the present work was to analyze surface color changes and microbial growth (molds and yeasts) in apple cubes (Red Delicious and Granny Smith) immersed in orange juice (with or without ascorbic and citric acids) with the addition of preservatives (potassium sorbate and benzoate, 250-1000 ppm) during storage at 10°C in packaging plastic films with different gaseous permeability. Coliforms and sulfite reducing bacteria were also tested to analyze the sanitary conditions of the product. Results showed that the best condition for Red Delicious apples packaged in a high gaseous permeability film was reached using orange juice with ascorbic acid (30 mg/100ml), citric acid (0.2 g/100ml) sucrose (4 g/100ml) and potassium sorbate (250 ppm); under these conditions, storage life was 7 days. A higher storage life (>15 days) was obtained when the formulated product was packaged in a low gaseous permeability film. For Granny Smith apples the addition of chemical preservatives did not improve the quality of the product, in comparison to the quality of the apples maintained in orange juice with sucrose (8 g/100ml); storage life values were 10 and 15 days for high and low gaseous permeablity films respectively. In all cases the absence of pathogenic microorganisms was verified.