Interaction of Porcine Myofibrillar Proteins and Various Gelatins: Impacts on Gel Properties

Abstract

The objectives of this study were to determine the interaction between porcine myofibrillar proteins and various gelatins (bovine hide, porcine skin, fish skin, and duck skin gelatins) and their impacts on gel properties of porcine myofibrillar proteins. Porcine myofibrillar protein was isolated from pork loin muscle ( M . longissimus dorsi thoracis et lumborum ). Control was prepared with only myofibrillar protein (60 mg/mL), and gelatin treatments were formulated with myofibrillar protein and each gelatin (9:1) at the same protein concentration. The myofibrillar protein-gelatin mixtures were heated from 10°C to 75°C (2°C/min). Little to no impacts of gelatin addition on pH value and color characteristics of heat-induced myofibrillar protein gels were observed (p>0.05). The addition of gelatin slightly decreased cooking yield of heat-induced myofibrillar protein gels, but the gels showed lower centrifugal weight loss compared to control (p<0.05). The addition of gelatin significantly decreased hardness, cohesiveness, gumminess, and chewiness of heat-induced myofibrillar gels. Further, sodium dodecyl poly-acrylamide gel electrophoresis (SDS-PAGE) showed no interaction between myofibrillar proteins and gelatin under non-thermal conditions. Only a slight change in the endothermic peak (probably myosin) of myofibrillar protein-gelatin mixtures was found. The results of this study show that the addition of gelatin attenuated the water-holding capacity and textural properties of heat-induced myofibrillar protein gel. Thus, it could be suggested that well-known positive impacts of gelatin on quality characteristics of processed meat products may be largely affected by the functional properties of gelatin per se , rather than its interaction with myofibrillar proteins.

Effects of Gelatin Hydrolysates Addition on Technological Properties and Lipid Oxidation of Cooked Sausage

“…The pH value (pH 4.50) of pork skin gelatin was significantly lower than that of duck skin gelatin (pH 6.17); however, their hydrolysates showed similar pH values (p>0.05) since the final pH of gelatin hydrolysates were equally adjusted at the end of enzymatic hydrolysis process. According to a previous study, the final pH of gelatin is mainly affected by the acid/alkali treatment and neutralization in the gelatin extraction process ( Kim et al, 2012 ), and the general pH after neutralization is about 5.0–7.0 ( Noh et al, 2019 ). Thus, in this study, the pH difference between pork and duck skin gelatin could be associated with different manufacturing processes.…”

“…Previously, Lee and Chin (2016) reported that the addition of 1% pork skin gelatin had little effect on the water loss of cooked sausage. Recently, Noh et al (2019) reported that the positive impacts of gelatin on the water-holding capacity of processed meat products could be associated with the functional properties rather than the interaction between myofibrillar proteins and gelatin added. Thus, the inclusion level of 1% gelatin or gelatin hydrolysate might be insufficient to form a gel matrix to entrap moisture in the meat batter.…”

“…Commercial gelatin products used in the meat industry is mostly produced from pork skin and bovine hide ( Karim and Bhat, 2009 ), but gelatin extraction materials have been diversified now into poultry and fishery sources due to the risk of infectious diseases and religious reasons ( Tümerkan et al, 2019 ). In particular, poultry by-products such as feet and skins have been considered as promising materials for gelatin extraction ( Noh et al, 2019 ; Park et al, 2013 ). However, although some previous studies have found the techno-functional advantages of duck skin gelatin in processed meat products ( Kim et al, 2020 ), the efficiencies of pork and duck skin gelatin on the quality attributes of processed meat products have not been clearly compared.…”

Extraction of crude gelatin from duck skin: effects of heating methods on gelatin yield

“…However, this has negative implications because the disposal of by-products of duck production, including duck skin as biological waste, results in environmental pollution, which is a serious concern in the duck industry (Huda et al, 2013 ; Shim et al, 2018 ). Studies have shown that duck skin can be a potential alternative and novel source of collagen and gelatin (Noh et al, 2019 ). Kim et al ( 2017 ) have reported that the duck skin contains collagen, which can be used as a food additive.…”

Effects of hydrocolloids on the quality characteristics of cold-cut duck meat jelly

“…Globally, duck meat consumption accounts for ~4.53 million tons per annum [1], and duck meat consumption in Korea has increased consistently in recent years. Duck meat is not only highly preferred by consumers, but also it contains higher levels of unsaturated fat acids, iron, and niacin and lower levels of cholesterol and saturated fat compared to other meats [2,3]. According to Song et al [4], the nutritional characteristics of duck meat include omega-6 fatty acid, oleic acid, and excellent quality protein contents with considerable levels of essential amino acids.…”