Impact of lemon peel extract utilization on the biological values of Labneh during storage

Abstract

Lemon peel extract is a natural source of improving biologically and physiological functions. The aim of this study is to evaluate antioxidant, phenolic compounds, cytotoxicity and antimicrobial potential of lemon peel water extracts. Fresh and dried lemon peel extracts at concentrations of 1,2 and 4% were used to enhance Labneh quality. The hemical, physical, rheological, microbiological and sensory properties of the tested samples were evaluated (at 5±1°C) after 30 days of storage. Dried lemon peel extract (DLPE) recorded high radical scavenging activity, total phenolic and flavonoids contents compared to fresh lemon peel extract (FLPE). Dried lemon peel extract has potent, also, antiproliferative effects with CC50 = 61.2 μg/ml which provided a promising approach to its safety. DLPE possessed a great antimicrobial activity against all tested microorganisms. Meanwhile, total solids, ash, fat and protein values were slightly affected by extracts addition in Labneh samples. Antioxidant activity was increased with increasing the concentration of lemon peel extracts. Control sample recorded the highest values of hardness, while cohesiveness, gumminess and chewiness values were gradually decreased with higher concentrations of lemon peel extracts till the end of storage period. Total bacterial counts of Labneh samples were increased, reached the maximum after 7 days of storage. Psychrophilic bacteria, Yeasts & moulds and coliform bacteria were not detected in processed Labneh up to 3 weeks of storage period. The addition of lemon peel water extracts (fresh or dried up to 4%) improved Labneh flavor, body & texture and appearance at 5±1°C for 30 days of storage.

Traditional Fermented Dairy Products in Southern Mediterranean Countries: From Tradition to Innovation

“…Extracts from lemon peel were found to improve Labneh flavor, texture, appearance, and shelf life. This is due to the antioxidant and antimicrobial potential of lemon extracts [140]. Adding moringa at 2% to Halloumi cheese, Labneh, and buttermilk increased the content of iron; protein; calcium; vitamins C, B1, B2, and B3; and protein digestibility and extended their shelf life without impacting the organoleptic properties [141][142][143].…”

“…Addition of lemon peel extracts -Improvement of the flavor, texture, appearance, and shelf life [140] Halloumi cheese, Labneh and buttermilk Addition of moringa (2%) -Increase in iron, protein, calcium, vitamins (C, B1, B2, and B3), protein digestibility, and shelf life [141][142][143] Kishk Addition of purslane -Increase in mineral and protein contents [144] Labneh Addition of Lactobacillus casei and broccoli paste (5%)…”

Novel Perspectives on Food-Based Natural Antimicrobials: A Review of Recent Findings Published since 2020

“…Dairy products are susceptible to contamination and, therefore, pose a risk to consumer health due to their relatively short shelf life [ 66 ]. Microbial spoilage in these products can be delayed by using food-based extracts because of their phytochemical contents and antioxidant and antimicrobial activities [ 51 , 52 , 53 , 54 ].…”

“…El-Kholany et al [ 51 ] aimed to evaluate the effect of lemon peel extract, obtained using distilled water, on labneh cheese, on the physical properties, microbiological properties, and sensory qualities of the cheese. While the total bacterial count reached its maximum after 7 days of storage in the control labneh, the labneh cheese with added lemon extract showed no detection of psychrophilic bacteria, yeast, mold, and coliform bacteria for up to 3 weeks.…”

“…The extract exhibited antimicrobial activities against B. cereus , S. aureus , Listeria monocytogenes , B. subtilis , E. coli , S. typhimurium , P. aeruginosa , C. albicans , and A. fumigatus . Furthermore, the addition of lemon peel extract up to 4% was found to have a positive effect on the flavor of labneh cheese [ 51 ]. In another study, in which the extract obtained using pomegranate pomace was added to strawberry yogurt smoothies, the extract inhibited the growth of pathogenic bacteria and fungi such as L. monocytogenes , P. aeruginosa , K. pneumoniae , A. niger , and C. glabrata , and the extract-added smoothies exhibited lower microbial load compared to control samples.…”