Pomegranate By-Products as Natural Preservative to Prolong the Shelf Life of Breaded Cod Stick

Abstract

This work evaluated the efficacy of pomegranate byproducts, specifically peel powder, as valid preservatives for food quality. Ready-to-cook cod sticks breaded with pomegranate peel powder were prepared. Shelf-life tests were conducted on breaded cod sticks during refrigerated storage (17 days) at 4 °C, monitoring the pH, microbiological and sensory quality. In addition, the nutritional quality of both the breaded and control samples was assessed. The results highlighted that active samples showed higher phenol and flavonoid content and higher antioxidant activity compared to the control fish, suggesting that pomegranate peel powder was responsible for a significant increase in cod stick nutritional quality. Furthermore, the cod stick active breading led to a delay in microbial growth without affecting the sensory properties; rather, it helped slow down the sensory attribute decline during the refrigerated storage. The data suggest that using pomegranate byproducts in breaded cod stick was effective in prolonging its shelf life, as well as improving its nutritional quality. Therefore, pomegranate peel powder can be considered as a potential resource as natural food preservative.

Keywords: byproducts; fortified food; pomegranate; ready-to-cook fish; sustainable food.

Figure 1

Evolution of total mesophilic (a) and psycrhrotrophic (b) bacteria in breaded cod sticks during storage at 4 °C. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Solid Line: threshold for microbial acceptability set to 5 × 10⁶ log cfu/g. Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.

Figure 2

Evolution of Pseudomonas spp. in breaded cod sticks during storage at 4 °C. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Solid Line: threshold for microbial acceptability set to 10⁶ log cfu/g. Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.

Figure 3

Evolution of Shewanella in the breaded cod sticks during storage at 4 °C. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Solid Line: threshold for microbial acceptability set to 10⁶ log cfu/g. Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.

Figure 4

Trend of pH of breaded cod sticks. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.

Figure 5

Overall quality of the breaded cod sticks during storage. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Solid Line: threshold for sensory acceptability set to 5. Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.

Figure 6

Sensory attributes of breaded cod sticks: (a) color, (b) texture, (c) appearance, (d) odor. Data are presented as mean ± SD (n = 2). Symbols: experimental data; Solid Line: threshold for sensory acceptability set to 5. Con: sticks breaded with sole no active mix; A: sticks breaded with sole active mix; B: sticks breaded with pomegranate peel powder/no active mix; C: sticks breaded with pomegranate peel powder/active mix.