Effects of gelatin origin, bovine-hide and tuna-skin, on the properties of compound gelatin-chitosan films

With the purpose to improve the physico-chemical performance of plain gelatin and chitosan films, compound gelatin-chitosan films were prepared. The effect of the gelatin origin (commercial bovine-hide gelatin and laboratory-made tuna-skin gelatin) on the physico-chemical properties of films was studied. The dynamic viscoelastic properties (elastic modulus G', viscous modulus, G″ and phase angle) of the film-forming solutions upon cooling and subsequent heating revealed that the interactions between gelatin and chitosan were stronger in the blends made with tuna-skin gelatin than in the blends made with bovine-hide gelatin. As a result, the fish gelatin-chitosan films were more water resistant (∼18% water solubility for tuna vs 30% for bovine) and more deformable (∼68% breaking deformation for tuna vs 11% for bovine) than the bovine gelatin-chitosan films. The breaking strength of gelatin-chitosan films, whatever the gelatin origin, was higher than that of plain gelatin films. Bovine gelatin-chitosan films showed a significant lower water vapour permeability (WVP) than the corresponding plain films, whereas tuna gelatin-chitosan ones were only significantly less permeable than plain chitosan film. Complex gelatin-chitosan films behaved at room temperature as rubbery semicrystalline materials. In spite of gelatin-chitosan interactions, all the chitosan-containing films exhibited antimicrobial activity against Staphylococcus aureus, a relevant food poisoning. Mixing gelatin and chitosan may be a means to improve the physico-chemical performance of gelatin and chitosan plain films, especially when using fish gelatin, without altering the antimicrobial properties. © 2011 Elsevier Ltd.Peer Reviewe

Role of sulfites and 4-hexylresorcinol in microbial growth and melanosis prevention of deepwater pink shrimp (Parapenaeus longirostris) using a controlled atmosphere

A controlled atmosphere containing 48% CO2 and 7% O2 was used in association with refrigeration for storage of deepwater pink shrimp (Parapenaeus longirostris). Shrimp were treated with two different concentrations of sodium metabisulfite or 4-hexylresorcinol and subjected to the controlled atmosphere immediately after capture onboard ship or on arrival in port. Total volatile basic nitrogen, total viable counts, enterobacteria, lactic acid bacteria, and luminescent bacteria were determined, and black spot progression was evaluated. The combined effect of controlled atmosphere and melanosis inhibitors was used to delay black spot development as compared to the shrimp stored in ice alone. Storage under the controlled atmosphere without ice limited microbiological quality, namely, total viable counts, but enterobacterial growth was lower.Peer Reviewe

How individual value structures shape smart shopping experience and brand choices: an international perspective

This study explores the extent to which smart shopping, and particularly its effect on consumer attitudes towards store brands and national brands, is influenced by consumers' cultural values. Our conceptual model, based on Schwartz's value framework, was tested with a survey that sampled 1272 shoppers from six different countries (USA, UK, France, Germany, Italy and Spain). According to the results, the values that individuals acquire in their cultural environment significantly influenced their smart-shopper self-concept. Additionally, there were cross-country differences in consumers' value frameworks. As expected, smart shoppers' self-concept influenced their attitude towards both store brands and national brands, but was less influential in the former's case. These results have important implications for international marketing scholars and practitioners, especially regarding strategic aspects such as segmentation, positioning, and major communication strategies

The thrill of a smart purchase: Does country matter?

This is the accepted version of the following article: Quinones, M, Gómez-Suárez, M, Yagüe, M J(2021), The thrill of a smart purchase: Does country matter?. Int J Consum Stud. 2022; 46: 295–308, which has been published in final form at http://dx.doi.org/10.1111/ijcs.1267. This article may be used for non-commercial purposes in accordance with the Wiley Self-Archiving Policy authorservices.wiley.com/author-resources/Journal-Authors/licensing/self-archiving.htmlThe purpose of this article is to investigate the relationship of Schwartz's theory of basic individual values to smart shoppers' predisposition to purchase store brands, considering the mediating role of the smart shopper self-concept and the moderating role of the country of origin. After an initial qualitative analysis, survey data were collected from a sample of 868 shoppers in four western countries (Spain, France, Germany and the United States). Then, a series of statistical estimations was developed through structural equation modelling. The results of these sequential models showed metric equivalence, providing a basis for generating valid comparisons among the four countries. The final findings corroborate the idea that the individual's value structure has a direct and positive effect on the smart shopper self-concept and that this effect in turn influences the shopper's attitude towards store brands. The results also show that although the dimensions of the buyers' value structures are cross-country invariant, the set of values that best define smart shoppers differs significantly by country. Mixed results are found when the relationship between the smart shopper self-concept and the attitude towards store brands is analysed for each individual country. These outcomes offer international retail managers guidance on how to best stimulate smart shoppers' positive responses towards store brands.This research benefited from the Professorship Excellence Program in accordance with the multi-year agreement signed by the Government of Madrid and the Universidad Autónoma de Madrid-UAM (Line #3

Store brand evaluative process in an international context

This author accepted manuscript is deposited under a Creative Commons Attribution Non-commercial 4.0 International (CC BY-NC) licence. This means that anyone may distribute, adapt, and build upon the work for non-commercial purposes, subject to full attribution. If you wish to use this manuscript for commercial purposes, please contact [email protected] study was supported by the Spanish Ministry of Education (ECO2012-31517) and by the Spanish Ministry of Economy and Competitiveness (ECO2015-69103-R)

Functional and bioactive properties of collagen and gelatin from alternative sources: A review

The rising interest in the valorisation of industrial by-products is one of the main reasons why exploring different species and optimizing the extracting conditions of collagen and gelatin has attracted the attention of researchers in the last decade. The most abundant sources of gelatin are pig skin, bovine hide and, pork and cattle bones, however, the industrial use of collagen or gelatin obtained from non-mammalian species is growing in importance. The classical food, photographic, cosmetic and pharmaceutical application of gelatin is based mainly on its gel-forming properties. Recently, and especially in the food industry, an increasing number of new applications have been found for gelatin in products such as emulsifiers, foaming agents, colloid stabilizers, biodegradable film-forming materials and micro-encapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones. In the last decade, a large number of studies have dealt with the enzymatic hydrolysis of collagen or gelatin for the production of bioactive peptides. Besides exploring diverse types of bioactivities, of an antimicrobial, antioxidant or antihypertensive nature, studies have also focused on the effect of oral intake in both animal and human models, revealing the excellent absorption and metabolism of Hyp-containing peptides. The present work is a compilation of recent information on collagen and gelatin extraction from new sources, as well as new processing conditions and potential novel or improved applications, many of which are largely based on induced cross-linking, blending with other biopolymers or enzymatic hydrolysis. © 2011 Elsevier Ltd.Peer Reviewe

Functional and bioactive properties of collagen and gelatin from alternative sources: A review

The rising interest in the valorisation of industrial by-products is one of the main reasons why exploring different species and optimizing the extracting conditions of collagen and gelatin has attracted the attention of researchers in the last decade. The most abundant sources of gelatin are pig skin, bovine hide and, pork and cattle bones, however, the industrial use of collagen or gelatin obtained from non-mammalian species is growing in importance. The classical food, photographic, cosmetic and pharmaceutical application of gelatin is based mainly on its gel-forming properties. Recently, and especially in the food industry, an increasing number of new applications have been found for gelatin in products such as emulsifiers, foaming agents, colloid stabilizers, biodegradable film-forming materials and micro-encapsulating agents, in line with the growing trend to replace synthetic agents with more natural ones. In the last decade, a large number of studies have dealt with the enzymatic hydrolysis of collagen or gelatin for the production of bioactive peptides. Besides exploring diverse types of bioactivities, of an antimicrobial, antioxidant or antihypertensive nature, studies have also focused on the effect of oral intake in both animal and human models, revealing the excellent absorption and metabolism of Hyp-containing peptides. The present work is a compilation of recent information on collagen and gelatin extraction from new sources, as well as new processing conditions and potential novel or improved applications, many of which are largely based on induced cross-linking, blending with other biopolymers or enzymatic hydrolysis. © 2011 Elsevier Ltd.Peer Reviewe

Melanosis inhibition and SO2 residual levels in shrimps (Parapenaeus longirostris) after different sulfite-based treatments

The effectiveness of different sulfite-based treatments to prevent melanosis in fresh deepwater pink shrimp (Parapenaeus longirostris) was evaluated. Increasing the concentration of sulfites, different methods of application (immersion and dust) and synergy with other compounds, such as citric acid and chelants, were investigated. The level of SO2 residues in the muscle was determined in a selection of the most effective treatments. One-hour dip treatment with 50 g kg-1 sulfite, together with citric acid and chelants, was effective for melanosis prevention for at least one week. With this treatment, the statutory limit of 0.3 g kg -1 SO2 in edible part was not exceeded by the majority of samples analysed. © 2005 Society of Chemical Industry.Peer Reviewe