Investigation of the peptides with calcium chelating capacity in hydrolysate derived from spent hen meat.

Calcium peptide chelates are developed as efficient supplements for preventing calcium deficiency. Spent hen meat (SHM) contains a high percentage of proteins but is generally wasted due to the disadvantages such as hard texture. We chose the underutilized SHM to produce peptides to bind calcium by proteolysis and aimed to investigate chelation between calcium and peptides in hydrolysate for a sustainable purpose. The optimized proteolysis conditions calculated from the result of response surface methodology for two-step hydrolysis were 0.30% (wenzyme/wmeat) for papain with a hydrolysis time of 3.5 h and 0.18% (wenzyme/wmeat) for flavourzyme with a hydrolysis time of 2.8 h. The enzymatic hydrolysate (EH) showed a binding capacity of 63.8 ± 1.8 mg calcium/g protein. Ethanol separation for EH improved the capacity up to a higher value of 68.6 ± 0.6 mg calcium/g protein with a high association constant of 420 M-1 (25°C) indicating high stability. The separated fraction with a higher amount of Glu, Asp, Lys, and Arg had higher calcium-binding capacity, which was related to the number of ─COOH and ─NH2 groups in peptide side chains according to the result from amino acid analysis and Fourier transform infrared spectroscopy. Two-step enzymatic hydrolysis and ethanol separation were an efficient combination to produce peptide mixtures derived from SHM with high calcium-binding capacity. The high percentage of hydrophilic amino acids in the separated fraction was concluded to increase calcium-binding capacity. This work provides foundations for increasing spent hen utilization and developing calcium peptide chelates based on underutilized meat.

Bee pollen powder as a functional ingredient in frankfurters.

The objective of this study was to determine whether the addition of different pollen powder concentrations (0.0, 0.5, 1.0 and 1.5 g/100 g) to frankfurters had an influence on antioxidant potential and oxidative changes during storage, without detrimental effect on the quality of sausages. After cold storage of frankfurters, significant (P < 0.05) reductions of psychrotrophic bacteria populations were achieved with higher amounts of pollen (1.0 and 1.5 g/100 g). Good antioxidant properties and maintained TBARS values were accomplished by incorporating pollen into the frankfurters. In terms of quality parameters, statistically significant changes were obtained regarding the color, but sensory characteristics of the products were not disturbed. Also, the incorporation of pollen did not cause changes in terms of texture profile analyses of frankfurters. It can be concluded that the natural component, bee pollen powder, can be used as an antioxidant in frankfurter formulations, but further research is needed to estimate whether it can be an adequate replacement for synthetic antioxidants.

Functional and Bioactive Properties of Peptides Derived from Marine Side Streams.

In fish processing, a great amount of side streams, including skin, bones, heads and viscera, is wasted or downgraded as feed on a daily basis. These side streams are rich sources of bioactive nitrogenous compounds and protein, which can be converted into peptides through enzymatic hydrolysis as well as bacterial fermentation. Peptides are short or long chains of amino acids differing in structure and molecular weight. They can be considered as biologically active as they can contribute to physiological functions in organisms with applications in the food and pharmaceutical industries. In the food industry, such bioactive peptides can be used as preservatives or antioxidants to prevent food spoilage. Furthermore, peptides contain several functional qualities that can be exploited as tools in modifying food ingredient solubility, water-holding and fat-binding capacity and gel formation. In the pharmaceutical industry, peptides can be used as antioxidants, but also as antihypertensive, anticoagulant and immunomodulatory compounds, amongst other functions. On the basis of their properties, peptides can thus be used in the development of functional foods and nutraceuticals. This review focuses on the bioactive peptides derived from seafood side streams and discusses their technological properties, biological activities and applications.

Pomegranate Peel as Suitable Source of High-Added Value Bioactives: Tailored Functionalized Meat Products.

In the last few years, the consumer's concern with the relationship between health and diet has led to the search of foods with functional properties beyond the nutritional. In this framework, the consumption of pomegranate has increased due to their sensorial attributes and remarkable amounts of bioactive compounds, which generate, at the same time, huge amounts of by-products. A search in the Scopus database for the last 10 years has revealed the rising interest in pomegranate peel (PP), the main residue from this fruit. The meat industry is a food sector that has had to search for new alternatives to substitute the use of synthetic preservatives by new natural additives, to extend the self-life and keep the quality attributes of their processed products. This review sets out the main bioactivities of PP extracts, and their incorporation in meat products is elaborated. PP is a good source of bioactive compounds, including phenolic acids, flavonoids and hydrolyzable tannins, which have beneficial health effects. It can be concluded that the reformulation of meat products with PP extracts is a suitable strategy for enhancing their technological characteristics, in addition to conferring functional properties that make them healthier and potentially more acceptable for the consumer.

Shelf life study of healthy pork liver pâté with added seaweed extracts from Ascophyllum nodosum, Fucus vesiculosus and Bifurcaria bifurcata.

The effect of the addition of seaweed extracts from three brown algae species [Ascophyllum nodosum (AN), Fucus vesiculosus (FV) and Bifurcaria bifurcata (BB)], which are a great source of natural antioxidants, on the oxidative stability of refrigerated low-fat pork liver pâtés was studied. In the studied pâtés, half of pork fat was replaced with a mixture consisting of canola and high-oleic sunflower oil (75:25, v/v), thus improving their fatty acid profile in terms of polyunsaturated fatty acids (PUFA). In order to avoid the oxidation of PUFA in the new samples, seaweed extracts (500 ppm) were added. In addition, some samples were formulated with a synthetic antioxidant (BHT at 50 ppm) (BHT) and a control batch (CON) (without antioxidant) was also prepared, for comparison purposes. Thus, in total, five batches of liver pâté were prepared: CON, BHT, AN, FV and BB. Pâté samples were analyzed at 0, 45, 90, 135 and 180 days of refrigerated storage at 4 °C. The addition of seaweed extracts did not modify significantly (P > 0.05) the chemical composition or microbial characteristics of healthy pork liver pâté, except for the protein content, which resulted in a significant increase (≈2-3%) in the batches manufactured with addition of seaweed extracts compared to control samples. At the end of storage (180 days), L* values were significantly lower in the FV and BB batches than in the other batches. Moreover, the a* and b* values were also significantly lower in CON batches than in the samples with antioxidants added. Differences in oxidative parameters (conjugated dienes, TBARs and carbonyls) among batches were observed at the end of the storage time, showing samples with seaweed extracts a similar degree of protection against oxidation compared to BHT formulated samples. A decline of the volatile compounds was noted in all the batches during storage. The total volatile compounds at the end of the storage were significantly lower in BTH, AN, or BB batches than in control batches.

Feasibility of discrimination of dairy creams and cream-like analogues using Raman spectroscopy and chemometric analysis.

Dairy cream and its analogues with sunflower oil, coconut oil and palm oil in different milk fat/vegetable fat ratios were prepared and analysed using Raman spectroscopy. The linear discriminant analysis was conducted in order to classify the samples. Samples were well separated and displayed distinguishing linear arrangement along the principal component that expressed the variation in lipid unsaturation. Good separation of sunflower oil and milk fat samples was obtained in contrast to the samples with coconut and palm oil, where the substantial overlapping occurred. The method permitted classifying of the samples in terms of the type of fat used. Calibrated model was extremely sensitive (100%) for dairy cream. The results indicated that it is possible to consider the Raman spectroscopy coupled with chemometric analysis as a rapid way for the detection of dairy cream adulteration with sunflower, coconut and palm oils.