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20 pages, 5431 KiB

Open AccessArticle

Investigations on Changes in the Surface Geometrical Texture Caused by the Use of Corrosion Product Removers

by Aleksandra Ochal, Daniel Grochała, Rafał Grzejda and Agnieszka Elżbieta Kochmańska

Coatings 2025, 15(5), 539; https://doi.org/10.3390/coatings15050539 - 30 Apr 2025

Viewed by 332

In addition to ensuring the functionality of objects used in the household, transport or industry at large, applied design focuses on aesthetic qualities related to the external form and condition of a surface. At the same time, there is a trend for plastic, rubber or aluminium objects made by moulding (both injection and casting) to look as if they were made of natural materials. This effect is ensured by properly designed and manufactured surface textures in the mould seats. However, the working surfaces of the moulds often corrode as a result of inadequate maintenance and storage. The aim of this study was to find out how popular agents on the market dedicated to corrosion product removal would change the surface geometrical texture. During the prepared experimental plan, it was also decided to investigate the properties in this respect of one of the popular drinks (i.e., cola) which is sometimes used in workshop practice as an alternative corrosion product removal agent. Based on the results of the study, conclusions were drawn about the short- and long-term effects of the corrosion product removal agents. Full article

(This article belongs to the Special Issue Anti-corrosion Coatings of Metals and Alloys—New Perspectives)

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21 pages, 3599 KiB

Open AccessArticle

The Study of Combination of Biodegradable Packaging and Biocoating with Lactic Acid Bacteria as a Green Alternative for Traditional Packaging in Gouda Cheese

by Elvidas Aleksandrovas, Agnė Vasiliauskaitė, Justina Milerienė, Sandra Muizniece-Brasava, Inga Ciprovica, Epp Songisepp, Ida Rud, Lars Axelsson, Beatričė Kasparavičienė, Liis Lutter, Mindaugas Malakauskas and Loreta Šernienė

Coatings 2024, 14(7), 886; https://doi.org/10.3390/coatings14070886 - 16 Jul 2024

Cited by 3 | Viewed by 1934

Abstract

Biodegradable packaging, both alone and in combination with acid whey protein coatings, has been used to pack fresh Gouda cheese to improve preservation prior ripening or storage. This study involved three key components: (i) the selection of biodegradable packaging (BP), (ii) the development of a plain liquid acid whey protein concentrate, pectin-based edible coating (BP + Ch + Coating), and (iii) the incorporation of at least 6 log₁₀ CFU (colony forming units) mL⁻¹ Lacticaseibacillus paracasei (BP + Ch + Coating + Lp) and Lactobacillus helveticus (BP + Ch + Coating + Lh) strains. The created compositions were compared with cheese packed in conventional polyethylene (PE) packaging to evaluate their overall synergy effect in reducing microbiological spoilage and influencing chemical parameters in Gouda cheese during 45 days of ripening and cold storage. The evaluation included microbiological analysis (total LAB, Enterobacteriaceae spp., and fungi CFU) and quality assessment of pH, moisture content, water activity, texture, and colour (CEI system) during ripening and shelf life. Although biodegradable packaging (BP) alone did not protect the cheese effectively compared to conventional packaging (EVA/PE/EPC/PVDC), the combination of biodegradable packaging with a coating (BP + Ch + Coating) showed protective properties against Enterobacteriaceae spp. and mould, maintaining moisture, pH, and colour during ripening and storage. Incorporation of L. helveticus (BP + Ch + Coating + Lh) into the coating efficiently decreased the growth of fungi. Full article

(This article belongs to the Special Issue Degradation of Organic Coatings)

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20 pages, 7952 KiB

Open AccessArticle

Research on the Tribological Properties of a New Generation of Multi-Layer Nanostructured PVD Coatings for Increasing the Technological Lifetime of Moulds

by Janette Brezinová, Miroslav Džupon, Viktor Puchý, Jakub Brezina, Pavlo Maruschak, Anna Guzanová, Lýdia Sobotová and Miroslav Badida

Metals 2024, 14(1), 131; https://doi.org/10.3390/met14010131 - 22 Jan 2024

Cited by 1 | Viewed by 1939

Abstract

This paper presents the results of research focused on increasing the lifespan of HPDC moulds for casting aluminium alloys by applying duplex PVD coatings in combination with laser texturing the base material before the coatings’ deposition. This article describes the HPDC process and the degradation mechanisms of the moulds that arose during this process. The PVD nanostructured coatings utilised, the methods of their deposition, and the evaluation of their wear resistance are defined in this paper. The surface texturing process is described alongside the description of the analysis of the wear of the functional parts of the mould after decommissioning, which was carried out by visual inspection and optical and light microscopy. Three types of PVD duplex coatings were analysed during our study. The coatings were deposited using the LARC technology method (lateral rotating cathode). Subsequently, the procedure of laser texturing in the form of dimple textures using a laser was proposed. The quality of the coatings was evaluated under tribological conditions by means of the “Ball on disc” method. Based on the experimental results, recommendations for practice are established. Full article

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13 pages, 557 KiB

Open AccessArticle

Influence of Salting on Physicochemical and Sensory Parameters of Blue-Veined Cheeses

by Noemí López González, Daniel Abarquero, Patricia Combarros-Fuertes, Bernardo Prieto, José María Fresno and María Eugenia Tornadijo

Dairy 2024, 5(1), 93-105; https://doi.org/10.3390/dairy5010008 - 12 Jan 2024

Cited by 1 | Viewed by 2256

Abstract

Salting influences microbial growth, enzymatic activity, and biochemical reactions during ripening, thus contributing to the final quality of cheese. The aim of this study was to evaluate the influence of different salting methods (dry salting at 12, 24, and 48 h; salting in brine; and salting of partially drained curd, before moulding) on the chemical (moisture and salt content), physicochemical (pH, titratable acidity, and water activity), and sensory characteristics (texture profile analysis, colour, and sensory attributes) of industrial blue-veined cheese. Dry-salted cheeses had lower moisture content and water activity, and higher salt/moisture content and acidity than those salted in brine and in the partially drained curd. Dry-salted cheeses were also characterised by higher values for hardness, fracturability, and instrumental gumminess. Dry-salted cheeses showed differences only in the red/green colour component (a*), with the cheeses salted in the partially drained curd being less greenish. All cheeses scored high (around 7) in the tasters’ overall impression, with the dry-salted cheeses at 12 and 24 h showing optimal growth and distribution of mould, as well as better flavour and texture. Full article

(This article belongs to the Section Milk Processing)

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15 pages, 1356 KiB

Open AccessArticle

An Analysis of Changes in the Physicochemical and Mechanical Properties during the Storage of Smoked and Mould Salamis Made in Poland

by Jerzy Stangierski, Ryszard Rezler and Krzysztof Kawecki

Molecules 2023, 28(13), 5122; https://doi.org/10.3390/molecules28135122 - 29 Jun 2023

Cited by 7 | Viewed by 1721

Abstract

The aim of the study was to analyse changes in the physicochemical, rheological, and textural properties occurring during the storage of industrially produced smoked salami and mould salami. Tests on these cold cuts were conducted on the 2nd, 15th, 30th, and 45th days of storage. There was a significant increase in the pH value of the mould salami from 5.16 on the 2nd day to 5.42 on the 45th day (p < 0.05). There was a downward trend in the A_w of the smoked salami sample from 0.892 on the 2nd day to 0.873 on the 45th day. The A_w in the mould salami sample decreased from 0.889 on the 2nd day to 0.847 on the 15th day and then increased to 0.871 on the 45th day (p < 0.05). In the first two test periods, the smoked salami was characterised by a higher modulus of elasticity value than the non-smoked salami but lower loss tangent and dynamic viscosity values. The hardness of the whole bars, as well as the hardness of the salami pieces, was affected by their storage time and the related water content. The texture test results showed that the smoked salami was more resistant to compressive force than the mould salami, which affected the sensory evaluation and ease of slicing of this type of salami. Full article

(This article belongs to the Special Issue Physicochemical Study of Foods)

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23 pages, 5374 KiB

Open AccessArticle

A Digital Twin for Friction Prediction in Dynamic Rubber Applications with Surface Textures

by Valentina Zambrano, Markus Brase, Belén Hernández-Gascón, Matthias Wangenheim, Leticia A. Gracia, Ismael Viejo, Salvador Izquierdo and José Ramón Valdés

Lubricants 2021, 9(5), 57; https://doi.org/10.3390/lubricants9050057 - 20 May 2021

Cited by 15 | Viewed by 4430

Abstract

Surface texturing is an effective method to reduce friction without the need to change materials. In this study, surface textures were transferred to rubber samples in the form of dimples, using a novel laser surface texturing (LST)—based texturing during moulding (TDM) production process, developed within the European Project MouldTex. The rubber samples were used to experimentally determine texture-induced friction variations, although, due to the complexity of manufacturing, only a limited amount was available. The tribological friction measurements were hence combined with an artificial intelligence (AI) technique, i.e., Reduced Order Modelling (ROM). ROM allows obtaining a virtual representation of reality through a set of numerical strategies for problem simplification. The ROM model was created to predict the friction outcome under different operating conditions and to find optimised dimple parameters, i.e., depth, diameter and distance, for friction reduction. Moreover, the ROM model was used to evaluate the impact on friction when manufacturing deviations on dimple dimensions were observed. These results enable industrial producers to improve the quality of their products by finding optimised textures and controlling nominal surface texture tolerances prior to the rubber components production. Full article

(This article belongs to the Special Issue Machine Learning in Tribology)

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