Browning Inhibition in Fresh‐Cut Pears

color measurement. Four replicate plugs (representing 2 pears) were treated by immersion for 90 sec either in water (control) or in a solution containing 1% AA + 0.2% CaCl2 (pH 3.3) or 1.13% NaA + 0.2% CaCl2 (pH 7.7). Treated plugs were drained and placed in crystallizing dishes, covered with Petri dish lids, for storage at 4 C. Samples were evaluated for browning by visual examination and by measurement of tristimulus color coordinates in the CIELAB scale with a spectrocolorimeter (The Color Machine; Byk-Gardner, Inc., Silver Spring, MD) (Sapers and Douglas, 1987). In subsequent experiments carried out with fresh-cut pears, raw material firmness was determined with a McCormick Fruit Tester (Model FT 327; McCormick Fruit Technology, Yakima, WA) with the 7.94 mm plunger, and the pears were sorted into several ranges of firmness prior to treatment. In some trials, the pears were sanitized by immersion for 1 min in 200 ppm Cl2 (sodium hypochlorite solution, adjusted to pH 6.5 with citric acid). The pears were cut into 10 wedges with a stainless steel apple and pear slicer (Westmark Divisorex, Herscheid, Germany), and wedges damaged by pressure testing were discarded. Wedges were hand-trimmed to exclude tissue compressed by the wedge cutter, seed pockets, and most of the adjacent core tissue which are highly susceptible to browning during storage. Wedges from 5 or more pears were composited and held briefly in a solution containing 0.25% NaCl to prevent browning prior to application of the inhibitor dip. Sufficient wedges for each treatment were removed from the holding solution, drained in a colander, and immersed for 1 min in water (control) or solutions containing 4% NaE, 4% NaE 0.2% CaCl2, 4% NaE 50-400 ppm 4-HR, 4% NaE 0.2% cyst, or 4% NaE 0.2% CaCl2 50-100 ppm 4-HR. Treated wedges were drained in a colander and then distributed, 5 per container, in 10 × 12 × 5 cm plastic boxes. The containers either were over-wrapped with 0.6 mil plasticized polyvinyl chloride film, with 6 perforations (3.18 mm diameter) per box (Goodyear Films Division, Goodyear Tire & Rubber Co., Akron, OH) or were heat-sealed within MAP bags having specified OTR values of 1395 (laminated polyethylene film; Cypress Packaging, Rochester, NY) or 4650 cc/m2/day (coextruded polyethylene film; CVP Systems, Inc., Downers Grove, IL). Under the conditions of these experiments, the cypress packages contained ca. 14% O2 and 3% CO2 after 14 days at 4 C. Samples (duplicate containers per treatment Authors Sapers and Miller are with the U.S. Department of Agriculture, ARS, Eastern Regional Research Center, 600 E. Mermaid Lane, Wyndmoor, PA 19038. Direct inquiries to Dr. G.M. Sapers. ABSTRACT Treatments to control browning and maintain quality of fresh-cut pears were evaluated. Pear wedges were dipped in solutions containing sodium erythorbate, CaCl2 and 4-hexylresorcinol; packed in air or with a modified atmosphere (MAP); and stored at 4 C. Samples were evaluated for browning, microbial spoilage, and presence of off-flavors or loss of firmness. For treatments to be successful, pears had to be above a minimum firmness of 4 kg (d’Anjou) or 5 kg (Bartlett) when treated. Inhibitor treatments, in conjunction with MAP, controlled browning and maintained quality of fresh-cut Bartlett and d’Anjou (but not Bosc pears) for 12-14 days.