Chicken skin gelatine as an alternative to pork and beef gelatines

Poultry meat-processing industry produces considerably large amounts of by-products (such as chicken skins, heads, feathers, viscera, bones and legs) containing significant volumes of proteins, particularly collagen. One of the possibilities of advantageous utilization of these under-used by-products can be their application as a raw material rich in collagen for preparation of gelatine, a partial hydrolysate of collagen. In the present study, chicken skins obtained as a by-product from the chicken-breast processing were purified from non-collagen proteins, pigments and fats. Collagen was treated with proteolytic enzymes and the gelatine extraction was performed in distilled water at temperatures of 40, 50, 60, 70 and 80 °C during the constant extraction time of 60 min. The influence of the technological conditions on gelatine functional properties including viscosity, clarity, water holding and fat binding capacity, emulsifying and foaming properties was explored. Certain functional properties of prepared gelatines were significantly affected by the extraction temperature, while on some other properties the extraction temperature had no significant effect. Viscosity of prepared chicken skin gelatines was in the range from 3 to 5.7 mPa.s -1 , clarity from 1.5 to 2%, water holding capacity from 3.8 to 5.6 mL.g -1 , fat binding capacity from 0.9 to 1.3 mL.g -1 , emulsion capacity from 35 to 50%, emulsion stability from 73 to 88%, foaming capacity from 18 to 61% and finally foaming stability was from 4 to 39%. Chicken skin gelatines were compared with commercial food grade pork and beef gelatines. Prepared chicken skin gelatines showed better viscosity, fat binding capacity and foaming stability than mammalian gelatines, while water holding capacity, emulsifying stability and foaming capacity were not as good as in beef and pork gelatines. Emulsifying capacity was comparable with commercial gelatines. Therefore, chicken skin gelatine has the potential as an alternative to traditional gelatines from mammalian sources, such as pork or beef bones and skins. © 2019 Potravinarstvo Slovak Journal of Food Sciences

Thermal stability of prepared chicken feet gelatine gel in comparison with commercial gelatines

Gelatine is, due to its functional properties, currently widely used not only in the food industry (in the production of confectionery, dairy products, canned food) but also in pharmacy (soft and hard capsules) and cosmetics (creams, lotions) where it applies its ability to form thermoreversible gel stronger than most other gelling agents. What is more, it provides further excellent properties including emulsifying, foaming, stabilizing, film-forming, water and fat binding, texturizing, thickening, and adhesive attributes which makes it a very important hydrocolloid. Gelatine is obtained from the raw material of animal tissues containing collagen, usually mammalian skin or bones. For religious reasons in some countries, pork or bovine gelatine must be replaced by an alternative form, such as poultry or fish gelatine. The quality of gelatine is assessed mostly by the strength of gelatine gel which strongly depends on ambient temperature or humidity. Extraction conditions may also significantly affect the quality of gelatine. This study examined possible changes in the strength of gelatine gels prepared from laboratory-produced chicken feet gelatine and compared them with commercially available pork and beef gelatines at temperatures of 23, 29, and 35 °C at 60 and 80% humidity. While at 23 °C thermal stability of prepared chicken gelatine was monitored higher than in commercial gelatines, experiments at 29 and 35 °C provided equivalent results for chicken and commercial gelatines. Therefore, prepared chicken gelatine offers a significant potential to become an alternative to traditional gelatines. The information about gelatine gels thermal stability is of great importance for applications not only in the food; but also in the pharmaceutical industry. © 2020 Potravinarstvo Slovak Journal of Food Sciences

Polyphenols content and antioxidant activity of paprika and pepper spices

Paprika spices (Capsicium annuum) and black pepper spices (Piper nigrum) are very popular seasonings for culinary and industrial utilization due to the change of sensory quality (taste, aroma, color) of foods and meals with their addition; their health promoting properties; and also, relevant antioxidant activity. Polyphenols are often responsible for the antioxidant capacity of plant products therefore in our study the content of polyphenols (TP) and antioxidant activity (TAA) were assessed in two common culinary spices - paprika spices (12, ground powder spices) and pepper spices (20, unground and ground, black, green, white and colored spices) of Czech, Austrian, and Slovak producers. These parameters were determined using spectrometric method, for total polyphenols method with Folin-Ciocaulteu reagent; the antioxidant activity (TAA) of aqueous and ethanolic extracts of spices was measured by DPPH method with IC50 evaluation. For paprika the total polyphenol content ranged from 14.67 to 28.78 mg GAE.g-1. However, there is only weak connection between the pungency of the spices and the polyphenolic amount, the hotter samples of paprika spices have slightly higher values of TP than sweet types. Also, more pungent paprika products showed a higher potency in scavenging of DPPH free radical than sweeter ones; and ethanolic extracts had slightly higher TAA values (8.73 to 16.17 mg AAE.g-1) than aqueous spice extracts (4.45 to 16.24 mg AAE.g-1). Phenolic amount for pepper spices was assessed in the range of 12.03 to 22.88 mg GAE.g-1. Generally, paprika spices contained more polyphenols than pepper spices. The values of TAA of pepper spices were in the range from 7.07 to 15.81 mg AAE.g-1 for aqueous extracts and from 8.25 to 15.93 mg AAE.g-1 for ethanolic extracts respectively. The highest TAA values were observed for white ground pepper and unground black pepper spices. Unground black pepper samples had higher TAA than ground black pepper. The extent of antioxidant activity of paprika and pepper spices was quite similar. The total phenolics contents in spices were correlated to antioxidant activity only slightly. © 2017 Potravinarstvo Slovak Journal of Food Sciences, License

Preparation of protein products from collagen-rich poultry tissues

Chicken stomachs are by-products obtained from the poultry processing in slaughterhouses. Their amount has been gradually increasing as a consequence of a continually rising poultry consumption. Since these animal tissues are still rich in proteins, mainly collagen, fat, and minerals, it is essential and beneficial to investigate the appropriate management and further processing. Collagen could be extracted from chicken stomachs and used as a raw material in the food, cosmetic, medical, and also pharmaceutical industry. This paper is to investigate possibilities of such extraction of collagen products, gelatines, or alternatively hydrolysates, from chicken stomachs after prior biotechnological treatment with the proteolytic enzyme Protamex. In this experiment, non-collagenous proteins were removed from stomachs using 0.03 M NaOH and 0.2 M NaCl. Subsequently, the tissue was defatted applying acetone and the enzyme Lipolase. Purified and dried collagen was then treated with the proteolytic enzyme Protamex. In the last step, gelatine was extracted from the tissue in hot water. The influence of selected processing parameters on the extraction efficiency and final product quality was monitored. The extraction conditions included the amount of the added enzyme (0.1 - 0.4%) and the extraction temperature of between 60 and 65 °C. The total gelatine yield ranged from 43.80 to 96.45% and the gel strength varied from 2 ±0 to 429 ±8 Bloom. The enzymatic treatment of the raw material is an economical and ecological alternative to traditional acid or alkaline treatments. Extracted gelatine with the gel strength of 100 - 300 Bloom would be suitable for the applications in the food industry in the production of confectionery, marshmallow, aspic or dairy products. © 2020 Potravinarstvo Slovak Journal of Food Sciences, License: CC BY 3.

Phenolic compounds, vitamins C and E and antioxidant activity of edible honeysuckle berries (lonicera caerulea l. var. kamtschatica pojark) in relation to their origin

Honeysuckles are frost tolerant plants providing early-ripening fruits with health-promoting properties which have been used in traditional medicine in China. This study evaluates the impact of the climatic conditions of two areas on the chemical composition and antioxidant activity (AOA; by DPPH-2,2-diphenyl-1-picrylhydrazyl and photochemiluminescence assays) of eight cultivars of honeysuckle berries (Lonicera caerulea L. var. kamtschatica Pojark) of various ripening times. Expectedly, chemical composition and AOA values varied depending on the cultivars, locality and selected methods. Berries from Lednice (the area with more sunshine) showed higher average contents of total monomeric anthocyanins (TMAC; pH differential absorbance method), vitamins C and E and total phenolics (high-performance liquid chromatography). In contrast, berries from zabcice (the area with more rain) performed higher average contents of total phenolics and flavonoids (UV/VIS spectroscopic analyses). Interestingly, fundamental amounts of chlorogenic acid were determined irrespective of the locality. Regarding TMAC and vitamin C content, early ripening Amphora from both areas has been assessed as the best cultivar; concerning the content of phenolic compounds, Fialka from both areas and Amphora from Lednice is considered as the most valuable. The obtained results may facilitate the selection of the most valuable cultivars for both producers and consumers.IGA/FT/2022/004Internal Grant Agency of Tomas Bata University in Zlin [IGA/FT/2022/004

Dietary intakes of minerals, essential and toxic trace elements for adults from Eragrostis tef L.: A nutritional assessment

This study analysed the contents of thirty-six mineral and trace elements in teff (Eragrostis tef L.) grains. What is more, dietary intakes were calculated. Inductively coupled plasma mass spectrometry (ICP-MS) was used to assess mineral and trace element contents. Consequently, the appropriate Recommended Dietary Allowance (RDA) or adequate intake (AI), and provisional tolerable weekly intake (PTWI) or provisional tolerable monthly intake (PTMI) values for adults were determined according to the Food and Agriculture Organization/World Health Organization (FAO/WHO) and Institute of Medicine (IOM) regulations. Teff is a significant contributor to RDAs and AIs for females in the following order: Mn > Cu > Zn ≥ Mg > Fe ≥ P and Ca. For males, teff contributes in the order, Mn > Cu > Fe > Zn ≥ P ≥ Mg > and Ca. The concentration of arsenic (65–9 μg/kg) in brown teff originating in Bolivia exceeded the average acceptable value set by Reg. No. 1881 of 6–50 μg/kg in cereals consumed in the EU. The PTWIs or PTMIs for Al, Cd, Sn and Hg were all under 7%, which is below the limits of toxic element intake related to the body weight of 65 kg for adult females and 80 kg for males, set by the FAO/WHO. Teff grains can be recommended as a valuable and safe source of minerals and trace elements. © 2018 by the authors. Licensee MDPI, Basel, Switzerland.internal grant of TBU in Zlin [IGA/FT/2018/006

Fruits of black chokeberry aronia melanocarpa in the prevention of chronic diseases

In recent years, growing attention has been focused on the utilization of natural sources of antioxidants in the prevention of chronic diseases. Black chokeberry (Aronia melanocarpa) represents a lesser known fruit species utilized mainly as juices, purees, jams, jellies and wine, as important food colorants or nutritional supplements. The fruit is valued as a great source of antioxidants, especially polyphenols, such as phenolic acids (neochlorogenic and chlorogenic acids) and flavonoids (anthocyanins, proanthocyanidins, flavanols and flavonols), particularly cyanidin-3-galactoside and cyanidin-3-arabinoside, as well as (-)-epicatechin units. The berries of A. melanocarpa, due to the presence and the high content of these bioactive components, exhibit a wide range of positive effects, such as strong antioxidant activity and potential medicinal and therapeutic benefits (gastroprotective, hepatoprotective, antiproliferative or anti-inflammatory activities). They could be also contributory toward the prevention of chronic diseases including metabolic disorders, diabetes and cardiovascular diseases, because of supportive impacts on lipid profiles, fasting plasma glucose and blood pressure levels. © 2017 by the authors.internal grant agency of Tomas Bata University in Zlin [IGA /FT/2017/006

Free and bound amino acids, minerals and trace elements in matcha (Camellia sinensis L.): A nutritional evaluation

This study provides an overview of free and bound amino acids, minerals and trace elements content in matcha including evaluation of their dietary intakes. The analyses employed IEC and ICP-MS methods. Theanine followed by Glu, GABA, Thr and Me were the most abundant free amino acids. Considering bound amino acids, Glu, Asp, Leu, Lys, Arg and Val were the most frequent. The amino acid score (AAS) for matcha (40.2 %) is comparable to the AAS for wheat and sunflower proteins. Ile and Thr were evaluated as limiting amino acids. Regarding recommended daily allowance (RDA), the contributions of Cys and Met were up to 8%. Matcha is contributor to Adequate Intake (AI) or RDA for males in the following order: Mn (up to 15 %) > Cu > Fe (up to 7%). Similarly, for females, matcha contributes to RDA or AI values in this order: Mn (up to 19 %) > Cu > Zn (up to 5%). It has not been proved that matcha is a significant source of Se and Cr. A daily serving portion of 5 g does not contribute to PTWI (Provisional tolerable weekly intake) and PTMI (Provisional tolerable monthly intake) for Al, Sn, Cd and Hg. © 2020 Elsevier Inc

Fatty acids composition of vegetable oils and its contribution to dietary energy intake and dependence of cardiovascular mortality on dietary intake of fatty acids

Characterizations of fatty acids composition in % of total methylester of fatty acids (FAMEs) of fourteen vegetable oils—safflower, grape, silybum marianum, hemp, sunflower, wheat germ, pumpkin seed, sesame, rice bran, almond, rapeseed, peanut, olive, and coconut oil—were obtained by using gas chromatography (GC). Saturated (SFA), monounsaturated (MUFA) and polyunsaturated fatty acids (PUFA), palmitic acid (C16:0; 4.6%–20.0%), oleic acid (C18:1; 6.2%–71.1%) and linoleic acid (C18:2; 1.6%–79%), respectively, were found predominant. The nutritional aspect of analyzed oils was evaluated by determination of the energy contribution of SFAs (19.4%–695.7% ERDI), PUFAs (10.6%–786.8% ERDI), n-3 FAs (4.4%–117.1% ERDI) and n-6 FAs (1.8%–959.2% ERDI), expressed in % ERDI of 1 g oil to energy recommended dietary intakes (ERDI) for total fat (ERDI—37.7 kJ/g). The significant relationship between the reported data of total fat, SFAs, MUFAs and PUFAs intakes (% ERDI) for adults and mortality caused by coronary heart diseases (CHD) and cardiovascular diseases (CVD) in twelve countries has not been confirmed by Spearman’s correlations. © 2015 by the authors; licensee MDPI, Basel, Switzerland.internal grant agency of Tomas Bata University in Zlin [IGA/FT/2015/010

Polyphenol content and antioxidant capacity of fruit and vegetable beverages processed by different technology methods

The purpose of the natural drinks production is the preservation of biologically active compounds in maximal amount in prepared drinks. The issue is the loss of these substances due to conventional conservation methods, such as pasteurization. Pascalization, a conservation method using high pressure, performs a new trend in conservation. According to available research, it causes only a minimal loss of bioactive compounds. Influence of conservation technology of fruit and vegetable beverages on the content of bioactive substances - polyphenols, flavonoids and on their antioxidative activity has been investigated. Their content has been compared in fresh juice samples, in samples conserved by pasteurization and after the appliance of high pressure treatment - pascalization (HPP). HPP has a positive effect on total antioxidative capacity of juices - broccoli with apple (increase of the amount from 189.12 mg.100 mL-1 to 217.12 mg.100 mL-1) and beetroot and on total polyphenol content within all samples of beverages except from carrot juice. Decrease of the amounts of flavonoids has been observed within all beverages. For drinks after pasteurization treatment there is evident the decrease of total polyphenols content and total antioxidant activity, besides carrot juice, where the antioxidant capacity value had increased from 37.24 to 43.14 mg.100 mL-1. The flavonoid content of fruit and vegetable juices after heat treatment had increased only in the juice prepared from broccoli with apple (from 40.71 mg.100 mL-1 to 45.14 mg.100 mL-1), the content in other juices had decreased. However, the decrease of the flavonoid content is lower after heat treatment in comparison to HPP, except the samples of cabbage juice with apple. With the exception of flavonoids, HPP has been proved as a gentle conservation technology enabling preserving higher amounts of bioactive substances with antioxidative properties if compared with the heat treatment. For the samples treated by HPP there was observed statistically significant difference in comparison with fresh juice in all factors mentioned above (p < 0.05). © 2016 Potravinarstvo