Evaluation of Antimicrobial and Preservative Effects of Cinnamaldehyde and Clove Oil in Catfish (Ictalurus punctatus) Fillets Stored at 4 °C

Abstract

This study aimed to evaluate cinnamaldehyde (CN) and clove oil (CO) effectiveness in inhibiting growth and killing spoilage and total aerobic bacteria when overlaid with catfish fillet stored at 4 °C. A 1.00 mL concentration of CO inhibited growth by 2.90, 1.96, and 1.96 cm, respectively, for S. baltica, A. hydrophilia, and total bacteria. Similarly, treatment with 1.00 mL of CN resulted in ZIB of 2.17, 2.10, and 1.10 cm, respectively, for S. baltica, A. hydrophilia, and total bacteria from catfish exudates. Total bacteria from catfish exudates treated with 0.50 mL CN for 40 min, resulted in a 6.84 log decrease, and treatment with 1.00 mL resulted in a 5.66 log decrease at 40 min. Total bacteria exudates treated with 0.50 mL CO resulted in a 9.69 log reduction at 40 min. Total bacteria treated with 1.00 mL CO resulted in a 7.69 log decrease at 7 days, while untreated pads overlaid with catfish resulted in ≥9.00 CFU/mL. However, treated absorbent pads with catfish at 7 days, using 0.50 mL and 1.00 mL CN, had a bacterial recovery of 5.53 and 1.88 log CFU/mL, respectively. Furthermore, CO at 0.50 mL and 1.00 mL reduced the bacteria count to 5.21 and 1.53 log CFU/mL, respectively, at day 7.

Keywords: absorbent food pads; catfish; cinnamaldehyde; clove oil; essential oil; spoilage; storage.

Figure 1

Reduction of bacterial count in store-bought catfish treated with CN. n = 3 for each concentration on each day. Concentration of treatment to water was at 1:10 mL per each treatment. Significance was defined as p ≤ 0.05. Differences within each day are represented by a and b. Data were analyzed by one-way ANOVA.

Figure 2

Reduction of bacterial count in store-bought catfish treated with CO. n = 3 for each concentration on each day. Concentration of treatment to water was at 1:10 mL per each treatment. Significance was defined as p ≤ 0.05. Differences within each day are represented by a and b. Data were analyzed by one-way ANOVA.

Figure 3

Absorbent food pads treated with CN for storage of catfish at 4 °C. * represents plates that were above the highest level of bacteria count, too numerous to count. n = 3 for each concentration and trial. One mL of each prepared concentration was added to 5 mL of bacteria. The different letters (a, b, c) indicate significant differences between treatments on each day. Significance was defined as p ≤ 0.05. Statistical analysis for this study was conducted by means of one-way ANOVAs.

Figure 4

Absorbent food pads treated with CO for storage of catfish at 4 °C. * represents plates that were above the highest level of bacteria count, too numerous to count. Treatment with 1.00 mL CO resulted in no growth. n = 3 for each concentration and trial. One ml of each prepared concentration was added to 5 mL of bacteria. The different letters (a, b, c) indicate significant differences between treatments on each day. Significance was defined as p ≤ 0.05. Statistical analysis for this study was conducted by means of one-way ANOVAs.