Sustainable Design of Innovative Kiwi Byproducts-Based Ingredients Containing Probiotics

Abstract

Industrial processing of kiwifruits generates a large quantity of byproducts, estimated to be one million tons per year. The resulting byproducts are rich sources of bioactive components that may be used as additives, hence minimizing economic and environmental issues. In this study, kiwifruit byproducts were used to develop added-value food-grade ingredients containing probiotics. The byproducts were divided into peels and pomace. Both residues were inoculated with a selected strain of probiotic (Lacticaseibacillus casei 431®), and two variants were additionally enhanced with prebiotic sources (buckwheat and black rice flours). The inoculated powders were obtained by freeze-drying, and the final ingredients were coded as KP (freeze-dried kiwi peels), KBR (freeze-dried kiwi pomace and black rice flour), KPB (freeze-dried kiwi pomace and buckwheat flour), and KPO (freeze-dried kiwi pomace). The phytochemical profile was assessed using different spectrophotometric methods, such as the determination of polyphenols, flavonoids, and carotenoids. The kiwi byproduct-based formulations showed a polyphenolic content varying from 10.56 ± 0.30 mg AGE/g DW to 13.16 ± 0.33 mg AGE/g, and the survival rate of lactic acid bacteria after freeze-drying ranged from 73% to 88%. The results showed an increase in total flavonoid content from the oral to gastric environment and controlled release in the intestinal environment, whereas a maximum survival rate of probiotics at the intestinal end stage was 48%. The results of SEM and droplet size measurements revealed vesicular and polyhedral structures on curved surfaces linked by ridge sections. The CIEL*a*b* color data were strongly associated with the particular pigment in kiwi pulp, as well as the color of the additional flour. Finally, the ingredients were tested in protein bars and enhanced the value of the final food product regarding its phytochemical and probiotic content.

Effects of Green Kiwifruit Peel Extract on Sleep-Wake Profiles in Mice: A Polysomnographic Study Based on Electroencephalogram and Electromyogram Recordings

“…Further studies are needed to evaluate the sleep-promoting effects of GKPEE by polysomnography in human clinical trials. On the other hand, kiwifruit peel by-products generated plentifully in industrial processing have several applications, such as juice, smoothies, sweets, and ice creams [3]. The industrial utilization of fruit by-products is a major global trend for addressing the issue of sustainability in the food industry [35].…”

“…The industrial utilization of fruit by-products is a major global trend for addressing the issue of sustainability in the food industry [35]. As thousands of tons of kiwifruit by-products are discarded, it is necessary to consider them as a valuable source of health functional ingredients [3]. Therefore, the demonstration of the sleep-promoting effects of GKPEE provides an additional application that could contribute to the more efficient utilization of kiwifruit processing by-products and serve as a solution to certain economic and environmental problems.…”

“…Kiwifruit, often shortened to kiwi, is one of the most consumed and processed fruits worldwide because of its sensory properties and health benefits [1][2][3]. Kiwifruit, which belongs to the genus Actinidia, is cultivated in the tropics and subtropics, including New Zealand, Italy, Japan, and France [4].…”

Valorization of Food Processing By-Products

“…Another rich source of biocomponents is kiwi processing waste, such as peels and pomace. An application of the valorization of this by-product was reported by Ille et al [ 14 ]. After freeze drying, these substances and the obtained powder was added with black rice and buckwheat flour, inoculated with Lactobacillus spp.…”