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Several chemical compounds of seven faba bean cultivars—Sampo, Louhi, Talia, Tiffany, Julia, Gloria, and Vroma—grown in Finland were determined. The effect of seed maturity on the levels of vicine/convicine (vc), trypsin inhibitors, condensed tannins, phytic acid, lectins, and oligosaccharides was analyzed. The overall vc ratio remained similar in all the samples, and the largest amounts of vc were found in the early stage of the bean and decreased during maturation. Talia and Gloria had lower trypsin inhibition than the other cultivars. The smallest amounts of condensed tannins were found in the Talia and Gloria cultivars, and the largest in the Tiffany and Julia cultivars. Overall, it seems that maturation decreased the amount of condensed tannins. The fully mature faba bean contained an average of 10.3 to 13.4 g/kg (DW) phytic acid, and there was no difference between the seven cultivars. The highest lectin activity was found in the Sampo, Julia, and Tiffany cultivars, and the lowest activity was in Vroma and the mature seeds of Talia and Louhi. The simple sugars (rhamnose, galactose, glucose, sucrose, and fructose) were dominant in the early developmental stage, whereas the amount of long chain oligosaccharides (stachyose and verbascose) increased during maturation of beans, and the level of raffinose was similar in all developmental stages. In conclusion, the content of chemical compounds depended on the maturation stage and the faba bean cultivar. The low content of stachyose, verbascose, and raffinose in young Tiffany and Julia beans is beneficial when consumed as green bean.

The current practice of fish processing generates increasing quantities of side streams and waste, such as skin, heads, frames, viscera, and fillet cut offs. These may account for up to 70% of the fish used in industrial processing. Low-value fish catches, and under-utilized fish species comprise another source of side streams. These side streams have been discarded in the environment leading to environmental problems or they have ended up as low commercial value products, such as feed for fur animals and aquaculture. However, several studies have shown that fish side streams contain valuable bioactive ingredients and fractions, such as fish oils, proteins and peptides, collagen, gelatin, enzymes, chitin, and minerals. These compounds and fractions may provide the opportunity to develop novel applications in health promoting foods, special feeds, nutraceuticals, pharmaceuticals, and cosmetic products. Better utilization of side streams and low-value fish would simultaneously improve both the environmental and ecological sustainability of production. This review summarizes the current knowledge on fish and fish side streams as sources of high-value components such as peptides with antimicrobial, antioxidative, antihypertensive, and antihyperglycemic properties, proteins such as fish collagen and gelatin, fish enzymes, fish oils and fatty acids, polysaccharides like glucosaminoglycans, chitin and chitosan, vitamin D, and minerals. Production technologies for recovering the high-value fractions and potential product applications are discussed. Furthermore, safety aspects related to the raw material, technologies, and fractions are considered.

Phenolic compounds from plant sources have significant health-promoting properties and are known to be an integral part of folk and herbal medicines. Consumption of phenolics is known to alleviate the risk of various lifestyle diseases including cancer, cardiovascular, diabetes, and Alzheimer's. In this context, numerous plant crops have been explored and characterized based on phenolic compounds for their use as supplements, nutraceutical, and pharmaceuticals. The present review highlights some important source of bioactive phenolic compounds and novel technologies for their efficient extraction. These techniques include the use of microwave, ultrasound, and supercritical methods. Besides, the review will also highlight the use of response surface methodology (RSM) as a statistical tool for optimizing the recoveries of the phenolic bioactives from plant-based matrices.

Increasing the utilization of plant proteins is needed to support the production of protein-rich foods that could replace animal proteins in the human diet so to reduce the strain that intensive animal husbandry poses to the environment. The seeds of non-drug Cannabis sativa L. commonly referred to as hemp, are an important source of nutrition. Hempseed typically contains over 30% oil and about 25% protein, with considerable amounts of dietary fiber, vitamins, minerals, and specific phenolic compounds. However, the utilization of hempseed in food products is still at the very beginning. Previously, few research groups have reported trials on extracting and purifying proteins from hempseed. However, most of these methods have focused on protein isolates using different precipitation techniques, but these methods may not be suitable for commercial scale production, due to their intensive costs. Also, precipitation techniques may adversely affect the functional properties of hempseed proteins. This review aims to provide an overview of the current knowledge of the hempseed protein extractions and the functional properties of the enriched protein fractions.

Enzymatic hydrolysis of the oil hemp seed (FINOLA variety) cake and defatted hemp seed cake by SC-CO2 was carried out using Flavorpro 750 MDP and Promod 439 L enzymes, and proximate composition, proanthocyanidins, phytic acid, lignanamides and cannabinoids were determined from the separated phases. CIELAB* color parameters were measured, while trained panelists evaluated taste, color, and smell in 1-9 Hedonic scale. Ten lignanamides, seven cannabisin-type and three grossamide-type, were found, from the cannabinoids, only cannabidiolic acid was detected. Protein, fat, ash, lignanamides and proanthocyanidins remained mostly in the sediments after the hydrolysis process in the Flavorpro treated samples, while dry matter, fat and ash was released mostly to liquids in Promod treated samples. The defatting process by SC-CO2 resulted in a higher lightness and the enzymatic processing did not have effect on the color attributes. Sediments from the enzymatic treatment were tastier, with better color and smell than liquids.

Milk oligosaccharides are of high interest due to their bioactive properties. This study is the first to characterise milk oligosaccharides from native North European cattle breeds, as represented by 80 milk samples collected from eight native breeds originated from Norway (Norwegian Doela cattle and Norwegian Telemark cattle), Sweden (Swedish Mountain cattle), Denmark (Danish Red anno 1970), Iceland (Icelandic cattle), Lithuania (native Lithuanian Black and White) and Finland (Western Finncattle and Eastern Finncattle). Using high-performance liquid-chromatography chip/quadrupole time-of-flight mass-spectrometry, 18 unique monosaccharide compositions and a multitude of isomers were identified. No N-glycolylneuraminic acid was identified among these breeds. Western Finncattle milk was most abundant in neutral, acidic and fucosylated oligosaccharides. Further, Eastern Finncattle milk was significantly higher in acidic oligosaccharides and Icelandic cattle milk significantly higher in fucosylated oligosaccharides, compared to the mean. This study highlights specific native breeds of particular interest for future exploitation of milk oligosaccharides and breeding strategies.

Increasing the utilisation of plant proteins is needed to support the production of protein-rich foods that could replace animal proteins in the human diet so as to reduce the strain that intensive animal husbandry poses to the environment. Lupins, quinoa and hempseed are significant sources of energy, high quality proteins, fibre, vitamins and minerals. In addition, they contain compounds such as polyphenols and bioactive peptides that can increase the nutritional value of these plants. From the nutritional standpoint, the right combination of plant proteins can supply sufficient amounts of essential amino acids for human requirements. This review aims at providing an overview of the current knowledge of the nutritional properties, beneficial and non-nutritive compounds, storage proteins, and potential health benefits of lupins, quinoa and hempseed.

4th International Conference on Food Digestion -- MAR, 2015 -- Naples, ITALY, WOS: 000384789000006, Within the active field of in vitro digestion in food research, the COST Action INFOGEST aimed to harmonize in vitro protocols simulating human digestion on the basis of physiologically inferred conditions. A harmonized static in vitro digestion (IVD) method was recently published as a primary output from this network. To validate this protocol, inter-laboratory trials were conducted within the INFOGEST network. A first study was performed using skim milk powder (SMP) as a model food and served to compare the different in-house digestion protocols used among the INFOGEST members. In a second inter-laboratory study applying the harmonized protocol, the degree of consistency in protein hydrolysis was investigated. Analysis of the hydrolyzed proteins, after the gastric and intestinal phases, showed that caseins were mainly hydrolyzed during the gastric phase, whereas beta-lactoglobulin was, as previously shown, resistant to pepsin. Moreover, generation of free amino acids occurred mainly during the intestinal phase. The study also showed that a few critical steps were responsible for the remaining inter-laboratory variability. The largest deviations arose from the determination of pepsin activity. Therefore, this step was further clarified, harmonized, and implemented in a third inter-laboratory study. The present work gives an overview of all three inter-laboratory studies, showing that the IVD INFOGEST method has led to an increased consistency that enables a better comparability of in vitro digestion studies in the future. (C) 2015 The Authors. Published by Elsevier Ltd.

5th International Conference on Foodomics - From Data to Knowledge -- JAN 10-12, 2018 -- Cesena, ITALY, WOS: 000456758800042, PubMed ID: 30599953, In this work, the effects of maturation time and simulated gastrointestinal digestion on the molecular and peptide profiles of "Bresaola Valtellina" were assessed through the foodomics approach, in this case food proteomics and peptidomics combined to other analytical and biological assays, aiming at depicting a holistic food quality. Human digestion of this Italian cured meat product was simulated using an in vitro static protocol and the degree of proteolysis and the in vitro bioactivity of the soluble free compounds in the digestates were evaluated by biochemical assays, e.g. SDS-PAGE, size exclusion HPLC, HPLC/MS, 1H NMR, enzymatic and antioxidant activities. The obtained results demonstrated that in vitro gastrointestinal digestion contributed to a considerable release of myofibrillar proteins by the muscle tissue. Data from SDS-PAGE, peptidomic and size exclusion HPLC assays showed that the in vitro digestion largely degraded proteins of muscle tissue to peptides smaller than 250 Da. The released peptides were likely responsible for the inhibitory activity on amylolytic enzymes and for the antioxidant properties elicited by the gastric digestates of Bresaola. Overall, the results demonstrated the negligible role of ripening in making meat proteins more bioaccessible, whereas they confirmed the highly in vitro digestibility of meat proteins from Bresaola. This study represents a new approach merging proteomics and foodomics to evaluate the effect of ripening and in vitro digestion on the bioactivity and bioaccessibility of proteins and peptides of meat products., COST actionEuropean Cooperation in Science and Technology (COST) [FA1005 INFOGEST], The authors participate in the COST action FA1005 INFOGEST (http://www.cost-INFOGEST.eu/).

There is a growing interest on insects as food in Western countries. Currently, EU legislation limits the use of insects as food, however, new regulation coming to force in 2018 will clarify the situation. In the ScenoProt project funded by Strategic Research Council of Finnish Academy insects are considered as potential protein source for human consumption, and therefore, some food technological properties of insects are studied in the project. Scientific research has proven mealworm larvae and silkworm pupae originated protein fraction equal to meat protein in emulsion sausages. Generally, it is also of interest how unfractionated, chitin containing insect flour would affect the sensory properties of sausages. The objective of the present study was to investigate the consumer attitudes to Polish style sausages containing unfractionated house cricket (Acheta domesticus) flour. Lean and fatty meat was purchased from local supplier, and three different sets of smoked and cooked sausages were made. The basic recipe contained pork, water, house cricket flour, nitrite salt, and spices. Salt content of sausages was approx. 1.8%. In the first set 1/5, and in the second and third set approx. 1/6 of lean meat was replaced with house cricket flour. The fat content was approx. 12% in the first and 19–20% in the second and third set of sausages. The third set included ordinary Polish style sausage as a reference. Cooking loss of the sausages was acceptable, below 10%. Odor, texture and taste were evaluated by ordinary consumers (n=26) for the first, by media people (n=34) for the second, and by representatives of food industry (n=17) for the third set. Because of potential allergic reaction in shellfish sensitive people, the consumers were informed about the contents of the sausages. Consumer willingness to eat sausages again was recorded for the first and second set and free comments were collected for all the sets. The evaluation scale had five points (1=extremely negative, 5=extremely positive).Only in the first set the evaluations on odor, texture, and taste of the sausages averaged lower than 3. Even the willingness to eat sausages again was approx. 3. This may reflect the interest of the consumers towards food containing insects in general. The increased fat content in the second and third sets of sausages may be one factor responsible for increase in the valuation of the sensory parameters as Finnish consumers are used to the fat content of around 20 % in cooked sausages. In the third set the control sausages showed slightly higher acceptance for texture than the house cricket sausages. In free comments, dryness, dark colour, floury texture, and liver flavor were most often mentioned. In conclusion, consumers may accept non-fractionated house cricket flour as a sausage ingredient but its strong flavor may limit the level of inclusion or lead towards stronger, masking, spicing in the house cricket sausages.

The aim of this study was to investigate the application of elicitors (500 μM ascorbic acid, 50 μM folic acid, 5 mM glutamic acid and 50 ppm chitosan in 5 mM glutamic acid) during lentil germination up to 8 days as a strategy to increase germination rate and to enhance the accumulation of γ-aminobutyric acid (GABA) and phenolic compounds. The effect of elicitation on the protein profile and antioxidant and angiotensin I converting enzyme (ACE) inhibitory activities of sprouted lentils was also evaluated. The application of elicitors did not negatively affect the germination yield of lentils and no significant changes on the protein pattern of lentils germinated in the presence of elicitors were observed. Chitosan/glutamic acid increased by 1.6-fold the GABA content in lentil sprouts, whilst ascorbic and folic acids as well as chitosan/glutamic acid were highly effective to enhance the total content of phenolic compounds and the antioxidant activity of sprouted lentils. All elicited lentil sprouts showed ability to inhibit ACE activity (IC50: 9.5–11.9 μg peptides/mL). Therefore, elicitation can be considered a promising approach to improve the content of compounds with antioxidant and potential antihypertensive activities in lentil sprouts., This work was cofounded by Ministerio de Economía y Competitividad (Spain) through the project AGL2010-16310 and the European Union through FEDER programme. E. Peñas in indebted to Spanish “Ramón y Cajal” Programme for financial support and R.I. Limón to CSIC and European Social Fund providing a PhD fellowship.

Reducing salt (NaCl) intake is an important public health target. The food industry and catering services are searching for means to reduce the salt content in their products. This review focuses on options for salt reduction in foods and the sensory evaluation of salt-reduced foods. Simple salt reduction, mineral salts and flavor enhancers/modifiers (e.g., umami compounds) are common options for salt reduction. In addition, the modification of food texture and odor-taste interactions may contribute to enhanced salty taste perception. Maintaining consumer acceptance of the products is a challenge, and recent examples of the consumer perception of salt-reduced foods are presented.

Fermented foods and beverages were among the first processed food products consumed by humans. The production of foods such as yogurt and cultured milk, wine and beer, sauerkraut and kimchi, and fermented sausage were initially valued because of their improved shelf life, safety, and organoleptic properties. It is increasingly understood that fermented foods can also have enhanced nutritional and functional properties due to transformation of substrates and formation of bioactive or bioavailable end-products. Many fermented foods also contain living microorganisms of which some are genetically similar to strains used as probiotics. Although only a limited number of clinical studies on fermented foods have been performed, there is evidence that these foods provide health benefits well-beyond the starting food materials.

This study investigates the inhibition of angiotensin I-converting enzyme (ACE) and lipid peroxidation of fermented rapeseed and flaxseed meals. Rapeseed and flaxseed meals were fermented with Lactobacillus helveticus, Lactococcus lactis ssp. lactis, Bacillus subtilis, and Kluyveromyces marxianus monocultures at 37°C or 30°C for 48 h. The ACE-inhibition potencies increased by 20–37% during fermentation with L. helveticus and B. subtilis, whereas fermentation with other strains did not produce a significant change in ACE inhibition. The lowest IC50 value of 0.36 mg/mL was found with flaxseed fermented by L. helveticus. The same strains were also able to produce compounds that inhibited lipid peroxidation. The results showed that L. helveticus and B. subtilis degraded effectively rapeseed and flaxseed proteins as the amount of low molecular weight compounds increased during fermentation. ACE inhibition was found in low molecular weight (300–500 Da) fractions. In fermented rapeseed, the inhibition of lipid peroxidation was found in 1200–1300 Da fractions and fermented flaxseed showed inhibition in several fractions, first around 1300 Da and at lower molecular weight fractions 300–500 Da. The results demonstrated that fermentation with L. helveticus or B. subtilis produce compounds that may have beneficial effect on cardiovascular health.

The high nutritive value and diverse functional properties of milk proteins are well known. In recent years, intense scientific research has been focused on the identification of factors within bovine milk that may be relevant to improving human health. The best characterized wheybased bioactive proteins include α-lactalbumin, β-lactoglobulin, immunoglobulins, lactoferrin, lactoperoxidase and growth factors. These proteins exhibit a wide range of biological activities that may influence the digestive function, metabolic responses to absorbed nutrients, growth and development of organs and disease resistance. Some whey proteins may reduce the risks of chronic human diseases reflected by the metabolic syndrome. Whey proteins are a good source of various bioactive peptides which are encrypted within the proteins and can be released during gastric digestion or food processing by enzymes or microbes. Whey proteinderived peptides have been shown to exert a wide range of bioactivities affecting the cardiovascular, immune and nervous systems. The efficacy of a few peptides has been established in animal and human studies. A number of commercial whey-based protein products with potentital health benefits are on the market and this is envisaged to increase on a global scale.

Human leukemic THP-1 promonocytes are widely used as a model for peripheral blood monocytes. However, superoxide production during respiratory burst (RB) of non-differentiated THP-1 (nd-THP-1) cells is very low. Here we present a rapid and low-cost method for measuring the chemiluminescence (CL) of opsonized zymosan (OZ) induced RB which allows detection of Escherichia coli lipopolysaccharide (LPS) induced priming of nd-THP-1 cells on the basis of CL reaction kinetics. Maximum CL intensity obtained was 2.20 ± 0.25 and 1.30 ± 0.11 relative light units, while CL peak time was achieved at 18.1 ± 2.6 and 28.7 ± 1.3 min in primed and non-primed cells, respectively. The priming of nd-THP-1 cells with LPS evoked typical TNF-α and IL-6 production. We tested the effects of bovine lactoferrin and protein fractions from Lactobacillus helveticus BGRA43 fermented milk for potential anti-inflammatory effects on LPS primed nd-THP-1 cells. Four fractions were found to inhibit the OZ-induced CL in a dose-dependent manner (IC50 3–30 µg/mL), while lactoferrin inhibited CL to a lesser extent (IC50 270 µg/mL). These results suggest that measuring CL response of nd-THP-1 cells can serve as a method for screening anti-inflammatory compounds which could be used in reducing the risk of phagocyte-mediated inflammatory diseases. Copyright © 2010 John Wiley & Sons, Ltd.

Four microbial proteases (Alcalase, Flavourzyme, Neutrase and Protamex) were used for the preparation of whey protein hydrolysates. The aim of this research was to find out whether these hydrolysates can be used as a source of whey derived antioxidants. Hydrolyzed samples, including their unhydrolyzed protein solutions were tested by the ABTS (2,2′-azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) decolorization assay, by the total radical-trapping potential method and by the assay of liposomes peroxidation (fluorescence photometry). Antioxidant properties were enhanced by hydrolysis in most of cases. Alcalase hydrolysates were found as the most effective antioxidants as determined by ABTS assay (~50% of antioxidant activity at 0.1 mg ml−1 of hydrolysate in reaction) and fluorescence photometry. Liposomes were oxidized ~50% less (1.1 μM of α-tocopherol equivalent) with Alcalase hydrolysates additive (at 5.85 mg ml−1 of hydrolysate in reaction). Hydrolysates did not inhibit the oxidation of liposomes at concentrations below 1.0 mg ml−1 in reaction. On the contrary, results of total trapping potential method did not agree with findings observed in other tests. In this assay, Neutrase hydrolysates showed the best antioxidant properties. Pro-oxidant properties were observed in solutions containing (prior to the enzyme Protamex addition only) intact whey protein as determined by the measurement of the liposome peroxidation. The ABTS assay was optimized for the evaluation of the antioxidant activity in whey protein hydrolysates. The reaction time should be prolonged to avoid underestimation of the antioxidant activity.

Milk was fermented with a total of 25 lactic acid bacteria to assay in vitro inhibitory activity towards angiotensin I converting enzyme (ACE). The tested strains belonged to Lactobacillus acidophilus, Lactobacillus casei, Lacobacillus helveticus, Lactobacillus jensenii, Lactobacillus reuteri, Lactobacillus rhamnosus, Lactococcus lactis ssp. lactis, Lactococcus. raffinolactis and Leuconostoc mesenteroides ssp. cremoris. The ACE inhibitory potencies of theses strains varied and seven of them showing the highest ACE inhibitory activity were selected for further studies. The development of ACE inhibitory activity during fermentation correlated with degree of hydrolysis. Modification of fermentation conditions or pH control did not affect the ACE inhibitory activity. ACE inhibitory compounds from Lb. jensenii fermented milk were isolated by reversed phase HPLC and identified by MS-analysis and amino acid sequencing. The active compounds were peptides from β-casein. The milk fermented with Lb. jensenii caused a transient reduction of blood pressure in spontaneously hypertensive rats.

Potent angiotensin I-converting enzyme (ACE) inhibitory peptide mixtures were obtained from the hydrolysis of β-lactoglobulin (βLg) using Protease N Amano, a food-grade commercial proteolytic preparation. Hydrolysis experiments were carried out for 8 h at two different temperatures and neutral pH. Based on their ACE inhibitory activity, samples of 6 h of digestion were chosen for further analysis. The temperature used for the hydrolysis had a marked influence on the type of peptides produced and their concentration in the hydrolysate. Protease N Amano was found to produce very complex peptide mixtures; however, the partially fractionated hydrolysates had already very potent ACE inhibitory activity. The novel heptapeptide SAPLRVY was isolated and characterised. It corresponded to βLg f(36–42) and had an IC 50 value of 8 μ m , which is considerably lower than the most potent ACE inhibitory peptides derived from bovine βLg reported so far.

Proteins were isolated from potato tubers (Solanum tuberosum) at different physiological states, and by-products from the potato industry were used to evaluate their ACE-inhibitory and radical-scavenging potencies. Protein isolates and by-products were autolysed or hydrolysed by alcalase, neutrase and esperase. Hydrolysis increased the inhibition of the angiotensin-converting enzyme (ACE) and the radical-scavenging activity. The ACE-inhibitory potencies of the hydrolysates were high (IC50 = 0.018 − 0.086) and the by-product fractions showed ACE-inhibition also before hydrolysis. All samples exhibited low radical-scavenging activity, and hydrolysis for 2 h with proteases was needed to produce an increase in the activity. Ultrafiltration through 10–3 kDa membranes efficiently separated the ACE-inhibitory compounds into permeate fractions. The results of this study suggest that potato is a promising source for the production of bioactive compounds as ingredients for developing functional foods with a beneficial impact on cardiovascular health.

This paper shows the potential role of different ovine casein fractions and their hydrolysates to exert antioxidant activity. ABTS·+ decolorization assay was used to evaluate the antioxidant activity of the casein fractions (β-, κ- and αs-caseins) before and after their hydrolysis by pepsin, trypsin and chymotrypsin. Although the antioxidant activity increased in all the fractions after hydrolysis, the effect was particularly remarkable in the κ-casein fraction, which increased its antioxidant activity almost threefold. Further assays in a linoleic acid oxidation system showed that κ-casein hydrolysate inhibited lipid peroxidation. Analysis of the ovine κ-casein hydrolysate by RP-HPLC–MS/MS allowed the identification of 12 peptide sequences with potential antioxidant properties. One of the most abundant peptides, the fragment HPHPHLSF [f(98–105)] was chemically synthesized. Results showed that this κ-casein-derived peptide was a potent inhibitor of linoleic acid oxidation with an activity similar to that obtained with the synthetic antioxidant BHT. Although other peptides might also contribute, HPHPHLSF was the one most likely to be responsible for the activity found in the κ-casein hydrolysate., This study has received financial support from the projects AGL2005-03381 and CM-S0505-AGR-0153 financed by Ministerio Educación y Ciencia and Comunidad de Madrid, respectively.

Food-derived bioactive peptides represent one source of health-enhancing components. Bioactive peptides can be released during gastrointestinal digestion or food processing from a multitude of plant and animal proteins, especially milk proteins. Milk protein-derived bioactive peptides are considered to promote diverse activities, including opiate-like, mineral-binding, immunomodulatory, antimicrobial, antioxidant, antithrombotic, hypocholesterolemic, and antihypertensive actions. The exact mechanisms behind these effects are not fully understood. Opioid peptides are opioid receptor ligands with agonistic or antagonistic activities. Caseinophosphopeptides can form soluble organophosphate salts and may function as carriers for different minerals, especially calcium. Immunomodulating casein peptides stimulate proliferation of human lymphocytes and phagocytic activities of macrophages. Antimicrobial peptides kill sensitive microorganisms. Antithrombotic peptides inhibit fibrinogen binding to a specific receptor region on the platelet surface and also inhibit aggregation of platelets. Antioxidant peptides prevent peroxidation of essential fatty acids. Angiotensin-converting enzyme (ACE) inhibitory peptides can exert an antihypertensive effect. By modulating and improving physiological functions, bioactive peptides may therapeutic applications for the prevention or treatment of chronic diseases. This article reviews the current knowledge of the existence of milk protein-derived bioactive peptides, in vitro bioactivity, production, and the present evidence of health effects exerted by bioactive peptides.

Development of molecular methods has enabled detailed studies of the proteolytic system of Lactobacillus helveticus, which has a central role in the release of bioactive peptides during the fermentation of milk. The impact of general aminopeptidase (PepN) and X-prolyl dipeptidyl aminopeptidase (PepX) activity of L. helveticus on the level of angiotensin I-converting enzyme (ACE) inhibitory activity in fermented milk was elucidated by taking advantage of peptidase-negative derivatives of L. helveticus CNRZ32. According to the results, increased level of ACE-inhibitory activity was attained in milk fermented by the peptidase-deficient mutants. The ACE-inhibitory activity determined with the PepN-deficient strain decreased towards the end of fermentation, suggesting that PepN gives rise to a provisional accumulation of ACE-inhibitory peptides before their hydrolysis to shorter peptides or free amino acids. The ACE-inhibitory activity determined with the PepX-deficient strain increased throughout the fermentation, indicating specific blocking of the further hydrolysis of ACE-inhibitory peptides.

Antioxidants may function by preventing the formation of radicals or by scavenging radicals or hydrogen peroxide and other peroxides. Milk contains several antioxidant factors, like vitamins and enzymes. Possible antioxidant activity of milk proteins and hydrolysates has also been shown. Peptides generated from the digestion of milk proteins are reported to have antioxidative activities. Milk-derived antioxidative peptides are composed of 5–11 amino acids including hydrophobic amino acids, proline, histidine, tyrosine or tryptophan in the sequence. The structure–activity relationship or the antioxidant mechanism of peptides is not fully understood. Antioxidant activity of the hydrolysates seems to be inherent to the characteristic amino acid sequences of peptides derived, depending on the protease specificity. The results suggest that the hydrolysates from milk proteins could be used as natural antioxidants in enhancing antioxidant properties of functional foods and in preventing oxidation reaction in food processing. Further studies are needed to elucidate the role of antioxidative peptides in the protective function in humans.

Milk proteins exert a wide range of nutritional, functional and biological activities. Many milk proteins possess specific biological properties that make these components potential ingredients of health-promoting foods. Increasing attention is being focused on physiologically active peptides derived from milk proteins. These peptides are inactive within the sequence of the parent protein molecule and can be liberated by (1) gastrointestinal digestion of milk, (2) fermentation of milk with proteolytic starter cultures or (3) hydrolysis by proteolytic enzymes. Milk protein derived peptides have been shown in vivo to exert various activities affecting, e.g., the digestive, cardiovascular, immune and nervous systems. Studies have identified a great number of peptide sequences with specific bioactivities in the major milk proteins and also the conditions for their release have been determined. Industrial-scale technologies suitable for the commercial production of bioactive milk peptides have been developed and launched recently. These technologies are based on novel membrane separation and ion exchange chromatographic methods being employed by the emerging dairy ingredient industry. A variety of naturally formed bioactive peptides have been found in fermented dairy products, such as yoghurt, sour milk and cheese. The health benefits attributed to peptides in these traditional products have, so far, not been established, however. On the other hand, there are already a few commercial dairy products supplemented with milk protein-derived bioactive peptides whose health benefits have been documented in clinical human studies. It is envisaged that this trend will expand as more knowledge is gained about the multifunctional properties and physiological functions of milk peptides.

Milk whey protein-derived tetrapeptide, α-lactorphin (Tyr-Gly-Leu-Phe), binds to opioid receptors and possesses opioid-like activities. α-Lactorphin has lowered blood pressure in hypertensive and normotensive rats after subcutaneous administration. The antihypertensive effect was abolished by an opioid receptor antagonist. In vitro, α-lactorphin has improved endothelium-dependent vasorelaxation in rat mesenteric arteries via nitric oxide-mediated mechanism. Based on these findings, milk products or other foods containing α-lactorphin may lower blood pressure. Central opioid receptors mediate sedation and antinociception, which would be undesirable in such products. We investigated whether α-lactorphin elicits effects typical of centrally active opioids. Effects on nociception, locomotor activity, motor coordination, rectal temperature and duration of pentobarbital anaesthesia were evaluated in mice after intraperitoneal administration. α-Lactorphin, in contrast to opioid receptor agonist morphine, elicited no effect in the above-mentioned tests in mice. We conclude that the effects of α-lactorphin on blood pressure in humans are worth studying further.

et al., The bioavailability of dietary lipophilic components may be either increased or decreased by manipulating the microstructure and/or physicochemical properties of the foods that contain them. This article stresses how knowledge of the molecular, physicochemical, and physiological processes that occur during lipid ingestion, digestion, and absorption can be used to rationally design food structures to control these processes and therefore impact the rate or extent of lipid digestion and/or absorption. These approaches include controlling the molecular characteristics of the lipid molecules, altering lipid droplet size or interfacial properties, and manipulating food matrix structure and composition. Improved knowledge of the molecular, physicochemical, and physiological processes that occur during lipid ingestion, digestion, and absorption will facilitate the rational design and fabrication of functional foods for improved health and wellness.