Development and characterization of black mulberry (Morus nigra) pekmez (molasses) composite films based on alginate and pectin

Abstract

Production of composite films is an important approach to improve functionality of edible films, by combining different polysaccharides, proteins, and lipids. Carbohydrate-based composite films are most attractive, which have good filmforming ability due to their unique colloidal properties. Fruit purees include high polysaccharide content that plays a role to have desirable film properties including mechanical resistance, efficient barrier properties, and selective permeability against oxygen transmission. The purpose of this study was to characterize physical, barrier, mechanical, thermal, and water sorption properties of composite films formulated with different mulberry pekmez concentrations (26, 32, and 38 Brix) based on alginate or pectin. All film-forming solutions were showed shear thinning behavior with higher yield stress and viscosity-shear rate data were fitted to Ostwald de Waele model (R 2 ≥ 0.943). A noticeable decrease in tensile strength of films with increasing concentration was determined, but films prepared with high concentration showed more flexible. The mechanical properties of pectin films exhibited weakened properties compared to alginate films. Increasing pekmez concentration in the film matrix improved the water vapor permeability of alginate films, whereas pectin films showed reverse behavior as resulting in cracks and crack propagation within the structure. The sorption isotherms of films showed a typical profile of foods contain high soluble components and the Guggenheim-Anderson-deBoer (GAB) model gave a good fit for all of the obtained data. The results showed that mulberry pekmez films based alginate have a potential for food applications depends on the physical properties and for the replacement of non-biodegradable plastic packaging.

Influence of egg albumin and whey protein in the co‐encapsulation of betalains and phenolic compounds fromBougainvillea glabrabracts in Ca(II)‐alginate beads

“…All dispersions exhibited a non‐Newtonian shear thinning behavior, where viscosity decreased with increasing shear rate, probably due to the alignment of sodium alginate molecules in the flow direction (Belalia & Djelali, 2014). The increase of the shear rate results in the breakdown of the alginate chain entanglement, increasing its flexibility (Cakıroglu et al., 2020).…”

Erzurum un Karnavas Dut Pekmezi: Gastronomik Miras ve Coğrafi İşaretle Buluştuğu Noktada Gelenek ve Yenilik Arasındaki Diyalektik (Karnavas Mulberry Molasses of Erzurum: The Dialectic Between Tradition and Innovation at the Point Where Gastronomic Heritage Meets Geographical Indication)

“…Bu tespit aslında korunması gereken geleneksel bir yöntemdir (Eroğlu vd., 2016). Üretici modernleşme ile genç nüfusun köyden göç ettiğini ve bu durumun pekmez üretimini tehdit ettiğini belirtmektedir (Çakıroğlu, Dervişoğlu & Gül, 2020) Üreticinin belirttiği gibi yakacak odun bulma konusunda yaşanan zorluklar, üretim sürecini olumsuz etkilemektedir. Bu tespit, pekmez üretimindeki düzenleyici zorlukları temsil etmektedir (Smith vd., 2016).…”

Antibacterial films made with persimmon (Diospyros kakiL.), pectin, and glycerol: An experimental design approach

“…Thus, it is important to investigate new technical feasibilities to obtain products with higher added value from persimmon. Among the various possible applications is the production of biodegradable films from fruit (Çakıroğlu et al., 2020; Rangel‐Morrón et al., 2019; Torabi et al., 2019). The growing interest in the use of fruits for the development of films and coatings occurs to the presence of natural biopolymers, which can favor the development not only of biodegradable packaging for food but also active and/or intelligent packaging system, given bioactive compounds in the vegetable source (Galus et al., 2020; Otoni et al., 2017).…”