Effects of cold plasma on avocado pulp (PerseaamericanaMill.): Chemical characteristics and bioactive compounds

Abstract

The effects of cold plasma on the enzymatic activity, color, bioactive compounds, and antioxidant activity of avocado pulp with lime extract (PL) and without extract (PW) were studied. The experimental conditions applied varied with regard to time (10, 20, and 30 min) and gas flow (10, 20, and 30 ml). The gas flow combination of 20 ml/20 min applied in PL was efficient for reducing POD and PPO activities and browning index as well as for color maintenance. Cold plasma increased the phenolic and carotenoid levels in PW in T1 and T2 (gas flow 10 ml/10–30 min) and in PL in T3 and T8 (gas flow 30 ml/10 min and 20 ml/30 min), which contributed to the improvement in antioxidant activity. The phenolic showed a strong correlation with ORAC‐H in PL (0.85) and PW (0.75). Myristic and palmitic acid were reduced after applying cold plasma, however, oleic, linoleic, and linolenic increased the content. It is concluded that the synergistic effect of lime extract in avocado pulp with cold plasma technology is efficient at maintaining the quality characteristics and improving the bioactive content. Practical applications Cold plasma processing is an alternative method of effective maintenance for enzyme control, and it also shows promising results in the conservation of chemical quality and in increasing the levels of bioactive compounds and increasing the antioxidant capacity in fruit products, such as avocado pulp. Avocado has gained prominence in the market due to knowledge of its nutritional characteristics; however, its commercialization is hampered mainly by a high concentration of enzymes that cause enzymatic browning, such as polyphenol oxidase and peroxidase, which favor the appearance of degradation reactions, compromising the quality of the fruit. Available information on the effect of this conservation technology on this type of matrix has not been found, and this is one of the first studies to address the effect of cold plasma processing on avocado pulp, providing information for the food industry.

Effect of cold plasma on different polyphenol compounds: A review

“…The other process parameter, gas flow rate (argon), unaffected the total phenolic content (Garofulić et al, 2015). In another study, Batista et al (2021) showed a synergistic impact of treatment duration and gas flow rate while processing avocado pulp with cold plasma. The total phenolic content of avocado pulp and avocado pulp supplemented with lime extract increased when the treatment time was raised at a specific gas flow rate.…”

“…The positive impact of cold plasma exposure on the concentration of phenolic content in food matrices was reported by several authors. An increase in the phenolic content was reported in siriguela juice (Paixão et al, 2019), cashew juice (Rodríguez et al, 2017), Marasca cherry juice (Garofulić et al, 2015), allspice berries (Medvecká et al, 2020), turmeric powder (Hemmati et al, 2021), sugarcane juice (Manzoor et al, 2020), tomato pomace (Bao et al, 2020a), blueberry (Ji et al, 2020), avocado (Batista et al, 2021), grape pomace (Bao et al, 2020b), pitaya fruit (Li et al, 2019), tomato‐based beverage (Mehta et al, 2019), strawberry (Rana et al, 2020), and strawberry juice (Mehta & Yadav, 2020). The increase in the phenolic content was attributed to the reactive species generated by the cold plasma.…”

Environmentally Friendly Techniques for the Recovery of Polyphenols from Food By-Products and Their Impact on Polyphenol Oxidase: A Critical Review

“…Nonthermal techniques decrease the amount of PPO, resulting in the better maintenance of phenolic compounds [21]. Indeed, the reduction of PPO activity has a direct impact on the maintenance of polyphenols and could increase the recovery yield of polyphenols [28,132,135,136]. reported that raisins with a low PPO activity have a more quantity of polyphenols and accordingly have a richer nutritional value [137].…”

“…This leads to the loss of PPO activity. As a result of this reduction, the phenolic content of the food matrix is not used as the substrate of enzymatic browning and could be extracted with better quality [28]. To the best of our knowledge, there is no research evaluating the impact of nonthermal technologies on PPO during the extraction process of polyphenols from food by-products.…”

“…Hence, there is a growing demand for novel extraction methods with less solvent consumption, shorter time, and higher extraction yield [7]. Recently, many sustainable technologies such as microwave [26], ultrasound [27], cold plasma [28], pulsed electric field [29], pressurized liquid [30], and ohmic technology [31] have been utilized in the pre-treatment and extraction process of polyphenols. In these techniques, the temperature is not the decisive factor, and thus they require lower energy and have a lower effect on the loss of sensitive compounds, resulting in better recovery of bioactive compounds [32].…”