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This scientific opinion of EFSA deals with the risk assessment of the polymeric additive (butadiene, styrene, methyl methacrylate) copolymer cross-linked with 1,3-butanediol dimethacrylate, REF. No. 40560 for which the CEF Panel concluded that there is no safety concern for the consumer if the substance is used only up to 12% w/w in rigid poly(vinyl chloride) (PVC) materials at room temperature or below

This scientific opinion of EFSA deals with the risk assessment of the polymeric additive (butadiene, styrene, methyl methacrylate, butyl acrylate) copolymer cross-linked with divinylbenzene or 1,3-butanediol dimethacrylate, REF. No. 40563 for which the CEF Panel concluded that there is no safety concern for the consumer if the substance is used only up to 12% w/w in rigid poly(vinyl chloride) (PVC) materials at room temperature or below

This scientific opinion of EFSA deals with the risk assessment of the substance poly(12-hydroxystearic acid)-polyethyleneimine copolymer, CAS No. 124578-12-7, REF. No. 80350 for which the CEF Panel concluded that there is no safety concern for the consumer if the substance is prepared by the reaction of poly(12-hydroxystearic acid) with polyethyleneimine and used up to 0.1% w/w in plastics

The effect of curing agents (nitrate, glucose, ascorbic acid and chloride) and physical parameters (temperature, water activity and pressure) on porcine muscle cathepsin D has been studied. Chloride (in the assayed range 0 to 75 g Cl-/L) showed a strong inhibitory effect. Nitrate (in the assayed range 0 to 800 mg/L) and high concentrations of ascorbic acid (4 to 8 g/L) slightly inhibited cathepsin D. However, its activity increased when glucose was added up to 4 g/L. Cathepsin D activity was maximal when incubated at 33 to 53 degrees C, was affected by a decrease in water activity and unaffected by pressure.

Enzyme profile of the exudates from fresh and frozen/thawed pork has been assayed by using a semi-quantitative method (APIZYM). Only three enzymes (esterase-lipase, s-glucuronidase and α-glucosidase) showed significant differences (P < 0·01) between fresh and frozen/thawed pork. Different storage conditions were tested (freezing temperature: −10 to −60°C for 13 days and time of storage: 11 to 54 days at −18°C) but no significant differences were found among them. The APIZYM system would constitute a simple method for detecting frozen/thawed pork.

The effects of myoglobin on exopeptidases of Lactobacillus sake were determined. Inhibition of the aminopeptidases increased as the myoglobin concentration increased; aminopeptidase 3 was the most affected (90% inhibition). Aminopeptidases 1, 2, and 4 showed similar inhibition levels (around 60%). Myoglobin did not affect tripeptidase activity. Thus, myoglobin could limit amino acid generation in meat systems.

Cathepsins B, D, H and L as well as the glycosidases β-glucuronidase and N-acetyl-β-glucosaminidase were assayed for activity in fresh pork muscles stored for up to 20 days at 4°C and in 3- and 8-month dry-cured hams. Cathepsin B, H and L activities fell by 40–79% after 20 days while cathepsin D activity remained unchanged. All the enzymes were still active after 8 months of dry curing; with the recoveries found to be in the range 14–73%. Contaminant microorganisms did not appear to contribute to the observed proteinase activities. Cathepsins B, H and L activities from the 8-month ham have been confirmed as cysteine proteinases by the use of specific inhibitors. It was further confirmed that the cathepsin B and L activities in fresh pork and dry-cured ham were similar by isoelectrofocusing. We suggest that the presence of the curing salts may be important in stabilising the muscle enzymes during the curing process.

An enzyme sensor employing diamine oxidase from porcine kidney in combination with an oxygen electrode has been developed and optimised to estimate the content of total amines in dry-fermented sausages. The enzyme DAO was immobilised on a preactivated Immunodyne membrane using glutaraldehyde as cross-linking agent. The enzymatic determination was based on the measurement of the consumed O2 in a platinum electrode poised at −600 mV versus Ag/AgCl. The reaction was started by the direct injection of either the standard or meat extract on the enzymatic membrane. The immobilised enzyme could be used up to 30 analyses along the day without significant loss of sensitivity and could be stored at 4 °C showing good stability for at least 6 weeks. A good correlation was observed when comparing data obtained with the enzyme sensor to those obtained with a standard HPLC method. Thus, this sensor may be a reliable screening method to detect the presence of biogenic amines in dry-fermented sausages that can constitute a useful tool for quality control in the meat industry.

The angiotensin I-converting enzyme (ACE) inhibitory activities and antioxidant properties of thornback ray gelatin hydrolysates (TRGHs) prepared by treatment with proteolytic proteases from Bacillus subtilis A26, Raja clavata crude alkaline protease extract, Alcalase and Neutrase were investigated. All gelatin hydrolysates showed different degrees of hydrolysis and hydrophobic/hydrophilic peptides ratio. Moreover, they possess high protein content (70.04 ± 0.55–74.14 ± 0.28%). The antioxidant activity was assayed using various in vitro tests. The highest antioxidant activity was observed with hydrolysate obtained by treatment with A26 proteases (TRGH-A26) which exhibited a 1,1-diphenyl-2-picrylhydrazyl (DPPH) scavenging activity with a concentration that produces 50% of inhibition (IC50) of 1.98 ± 0.02 mg/ml of sample, reduced the ferric ions with an absorbance at 700 nm of 0.962 ± 0.07, prevents bleaching of β-carotene with 73.02 ± 1.90% inhibition and gave an antioxidative efficacy of 180 ± 0.08 µmol/ml α-tocopherol equivalents at 5 mg/ml in the phosphomolybdenum assay. However, gelatin hydrolysate treated with Alcalase (TRGH-Alcalase) was the most potent to prevent DNA oxidation. For the ACE inhibitory activity, all hydrolysates displayed ACE-inhibitory activity. TRGH-A26 and TRGH-Alcalase exhibited the highest activity with 85 ± 0.65 and 82 ± 0.49%, respectively, at 5 mg/ml. The results revealed that TRGHs could be used as ingredients to formulate functional foods.

Curing of ham involves a number of biochemical reactions, mainly related to lipolytic and proteolytic enzymes that contribute to the development of taste and flavour. Calpains are calcium-dependent enzymes that are known for their proteolytic activity in the first stages of meat tenderisation during postmortem storage. However, their activity in longer processing and in the presence of curing agents remains unclear. This study shows that the curing agents and process parameters have an important effect on m-calpain activity. This enzyme is activated with increasing concentrations of NaCl, obtaining a maximum at 0.34 M NaCl. Activation is also promoted by the addition of sucrose. In contrast, ascorbic acid, phosphates and particularly polyphosphates promote enzyme inhibition. Finally, calpain activity is not affected by nitrates and levels of water activity higher than 97%. Therefore, a careful selection of curing agent concentrations and process parameters is required for these types of processes, since the proteolytic activity is greatly affected and, as a consequence, the resulting tenderness and flavour of the final cured product.

The effect of different concentrations of myoglobin on the enzyme systems involved in lipid degradation were determined. Lipases, including both acid and neutral lipases and acid phospholipase, were inhibited by myoglobin. The neutral lipase was more susceptible to the inhibitory effect of myoglobin (35% of its initial activity at 1 mg/mL of myoglobin), followed closely by acid phospholipase ; acid lipase activity was affected to a lesser extent (less than 20% inhibition). This inhibition was also observed on the esterase activities, being greater on the neutral esterase activity (38% of its initial activity at I mg/mL of myoglobin) than on the acid one. In view of these results, myoglobin could be considered as an endogenous inhibitor which would determine the lipolytic activity in different type of muscles and therefore, the rate of generation of the free fatty acids.

Samples of muscle Semimembranosus were removed from light and heavy pork hams 3 days after slaughtering and analysed for chemical composition and proteolytic and lipolytic enzyme activity. Light hams were higher in moisture content and cathepsin (B and B+L) activity, and lower in peptidase (pyroglutamyl and dipetidyl IV) activity; the absence of further differences in proteolytic and in lipolytic enzymes could be due to large variation coefficients found within both ham classes. The use of principal components analysis displayed distinct patterns for light and heavy samples, with the latter being mainly characterised by greater peptidase-to-proteinase ratio and, to a lesser extent, by higher lipase activity. It was concluded that different chemical and enzyme patterns in fresh meat might be the cause of the wide variations in protein and lipid breakdown mechanisms that are often encountered in dry-cured pork derivatives.

A specific descriptive lexicon has been developed to evaluate the flavor of Spanish “Serrano” dry-cured ham. Dry-curing of pork legs produces a unique flavor difficult to define in regular meat terms. This lexicon for the flavor of dry-cured ham may be used by researchers to study flavor-development during the curing process. In this paper we have applied the lexicon to the study of dry-cured flavor developed in two different manufacturing processes that differ only in the length of the drying stage. The long processed dry-cured ham (12 months) is stronger for 8 of the 16 sensory attributes studied than the short processed dry-cured ham (7 months). During the long curing process of the ripening-drying stage, we found that the typical dry-cured flavor developed was defined by three factors: “cured flavor,”“off-flavor” and “pork flavor,” whereas in the short curing process typical dry-cured flavor was not fully developed.

The effect of biogenic polyamines (agmatine, cadaverine, putrescine, spermidine, and spermine) on the activity of pork muscle aminopeptidase and alanyl aminopeptidase was investigated. Agmatine (5 mM) showed a powerful inhibitory effect for both enzymes (more than 50% inhibition). Cadaverine and less intensely putrescine showed similar inhibitory effects for both enzymes. All assayed polyamines inhibited activity of both aminopeptidases except spermine and spermidine which did not affect aminopeptidase B. Thus, one of these inhibitors could be used to avoid the interference of alanyl aminopeptidase when assaying aminopeptidase B in muscle extracts.

Lipid composition of the muscle Semimembranosus was analyzed in the offspring of five different sire genetic types: Danish Duroc (DU), Dutch Large White (LW D ), English Large White (LW E ), Belgian Landrace x Landrace (BL x LR) and Belgian Landrace (BL), all of them mated to Landrace x Large White sows. The animals sired by DU boars showed the highest intramuscular fat, nonpolar lipid and free fatty acid contents. Fatty acid composition of triglycerides was little affected by genetic type. However, the fatty acid composition ofphospholipids was strongly affected, the highest monounsaturated fatty acid (MUFA) and the lowest polyunsaturated fatty acid (PUFA) percentages being found in the animals sired by BL x LR boars. On the other hand, the animals sired by BL boars, which showed the highest phospholipid content, showed the highest PUFA percentage. La teneur en matiere grasse intramusculaire et la composition en acides gras sont reliees a la qualite de la viande cuite. Cette etude examine les fractions lipidiques (acides gras, triglycerides et phospholipides) dans les muscles de 5 types genetiques de porc utilises dans l'industrie de la viande. Les resultats montrent que la composition en acides gras des triglycerides est peu influencee par le type genetique alors que celle des phospholipides l'est fortement.

The effect of endogenous dipeptides (carnosine and anserine) and peptidic fractions from meat extracts on aminopeptidase activity, alanyl and arginyl aminopeptidases purified from porcine skeletal muscle, was studied. Carnosine inhibited the activity of porcine arginyl aminopeptidase (RAP); the inhibition being stronger with the purified form of the enzyme than in the muscle extract. The RAP inhibition was competitive. One of the peptidic fractions isolated from meat extracts inhibited RAP activity But the degree of inhibition depended on the extent of purification. The major aminopeptidase present in muscle, alanyl aminopeptidase (AAP), was neither inhibited by natural dipeptides nor arty of the peptidic fractions. The study of meat inhibitory peptides provides a better understanding of the action of proteolytic enzymes during meat processing.

Following long dry-curing periods, Spanish “Serrano” ham develops a specific “dry-cured ham” flavor. To determine the effects of length of curing on flavor generation, replicate hams were processed for 7 or 12 mo prior to amino acid, peptide, and flavor evaluation by reverse phase HPLC, capillary zone electrophoresis, and sensory analysis, respectively. Generation of dry-cured and pork flavors correlated with the accumulation of amino acids. The relation of these components with sensory descriptors was examined by factor analysis. Results indicated that combinations and proportions of taste-active components produced the specific dry-cured flavor characteristic rather than an accumulation of any single flavor component.

Fermented meat products have a long tradition of use throughout human history, associated with health and safety. Spoilage bacteria are generally eliminated from these products during processing, the different steps of which (such as fermentation, curing, and drying) represent hurdles for these species. Microbial spoilage of fermented meat thus rarely occurs. However, raw meat harbors putative spoiling species and the initial microbiota of the batter follows different patterns of evolution during production. In order to limit possible development of defects, different strategies for spoilage control have been proposed in addition to the fermentation process per se, including modified atmosphere, high hydrostatic pressure, and biopreservation. Together, these contribute to ensure the microbial stability and safety of these fermented products.

International audience; Food products can be spoiled by bacteria, as they provide a rich nutrient source with physicochemical parameters, like pH and water activity, compatible with bacterial growth. In addition, the conditions used during food processing and storage, like temperature, addition of ingredients, and the use of modified atmosphere or vacuum packaging, exert a selective pressure that shapes the development of bacterial communities. Consequently, bacterial spoilage depends on the food matrices, on their production processes, and on their storage conditions. The main characteristics of bacterial spoilage of dairy, meat, and seafood products and products of vegetable origin are presented.

This chapter presents a review of proteomic studies dealing with lactic acid bacteria used as starters for the manufacture of various fermented foods. Most of the reported studies in the literature were performed under laboratory conditions mimicking conditions usually found during fermentation processes. A synthetic analysis is proposed for extracting the main features common to all these studies, or those characterizing either a species-specific or a stress-specific trait. A few articles reporting the application of proteomics directly in fermented matrices, aiming to analyze food safety or used as a tool for strain fingerprinting are also presented.

Panel members: Arturo Anadón, Mona-Lise Binderup, Wilfried Bursch, Laurence Castle, Riccardo Crebelli, Karl-HeinzEngel, Roland Franz, Nathalie Gontard, Thomas Haertlé, Trine Husøy, Klaus-Dieter Jany, Catherine Leclercq, Jean-Claude Lhuguenot, Wim Mennes, Maria Rosaria Milana, Karla Pfaff, Kettil Svensson, Fidel Toldrá, Rosemary Waring,Detlef Wölfle; International audience; This scientific opinion of EFSA deals with the risk assessment of the monomer 1,10-decanediamine, CAS No. 646-25-3, REF. No. 15260 for which the CEF Panel concluded that there is no safety concern for the consumer if the substance is only used as a co-monomer for manufacturing polyamide articles for repeated uses in contact with aqueous, acidic and dairy foodstuffs at room temperature or for short term contact up to 150°C and its migration does not exceed 0.05 mg/kg food.