Fatty acids of a salami-type sausage made of Baltic herring fillets, pork and lard

 The fatty acid composition of "fish wurst", a fermented salami-type sausage made of pork, lard and Baltic herring fillets (Clupea harengus var. membras) was investigated. Changes in the proportions of the 35 most abundant fatty acids were examined throughout the 1-month ripening period followed by a 4-month storage period. The fat composition of the product was stable (32–35%) and retained the characteristics of the main ingredients: oleic acid (37.4%, mean of three production batches) palmitic acid (23.7%) and linoleic acid (10.7%) from lard and fish, stearic acid (11.7%) mainly from lard, and palmitoleic acid (3.0%) and long-chain (C20–C24), polyunsaturated fatty acids (c.a. 6%) mainly from fish. During the 4-week ripening period a statistically significant increase (P≤0.05) was detected in the proportions of minor fatty acids only, i.e. eicosenoic acid (20 : 1n-9), eicosadienoic acid (20 : 2n-6), docosadienoic acid (22 : 2n-6) and docosatrienoic acid (22 : 3n-3). During the 4-month storage of the ripe sausage, the fatty acid composition stabilized. Only the proportion of stearic acid increased significantly during storage, from 11.7% to 12.5%. Received: 23 January 1998 / Revised version: 1 April 1998     

鱼肉羊肉猪肉复合香肠的开发研究

以新鲜的鱼肉、羊肉、猪肉为主要原料，根据其生物学和生物化学特性，运用正交试验设计和模糊数学理论，采用复合式即食香肠制作新工艺，研制了一种营养价值较高、风味独特、质构较好的鱼肉、羊肉、猪肉复合香肠。产品色泽均匀一致，淡红偏白，具有鱼肉、羊肉和猪肉的复合香味，肉质细嫩，口感良好，咸淡适宜，组织紧密，光滑有弹性。经产品质量检验，各项指标均符合肉与肉制品国家标准。主要原料配比为：鱼肉60g、羊肉54a、猪肉100a、猪肥腰15a.     

Changes in lipid composition and fatty acid profile of Nham,a Thai fermented pork sausage,during fermentation

Changes in lipid composition and fatty acid profile of Nham during fermentation were investigated. Total lipids of Nham were in the range 2–3%. The extracted lipid of initial Nham mix consisted mainly of triglycerides (TG), accounting for more than 75% of the total lipid, followed by phospholipids (PL) and a trace amount of diglycerides (DG) and free fatty acid (FFA). During fermentation, TG, DG and PL decreased with a concomitant increase in FFA, indicating lipolysis of Nham lipids during fermentation. Changes in fatty acids of the total lipids, non-polar and polar lipid fractions were observed during fermentation. In both total and non-polar lipid fractions, the major fatty acids found in a descending order were oleic (C18:1), linoleic (C18:2) and palmitic (C16:0) acids, which together accounted for 90% of the total fatty acids. Increases in fatty acid contents in both total and non-polar lipid fractions, were observed with a corresponding decrease in the quantity of fatty acids of phospholipids. As the fermentation proceeded, peroxide value generally increased while TBARS values decreased. Overall, lipid oxidation in Nham occurred during fermentation but did not cause the objectionable odour and taste in any Nham tested.     

Colour changes during manufacture of Galician chorizo sausage

 Galician chorizo sausage is a smoked-meat product containing chilli pepper. This study investigated changes in its colour (CIE colour coordinates L*, a* and b*, together with redness index, hue, chroma and perceived colour) during the curing process. Samples were obtained from three manufacturers (A, B and C) whose smoking and curing procedures differ markedly. Most of the colour measurement showed clear changes during curing. All measurement except external L* varied significantly among samples obtained from the different manufacturers. Pairwise comparisons indicated that in most cases there were significant differences between samples from manufacturer A (who smokes the product for only 6 h) and manufacturers B and C (who smoke the product for a longer period), but not between samples from manufacturers B and C. The pH, water activity and moisture content were also monitored; again, these variables differed significantly between A and B and between A and C, but not between B and C. Received: 8 October 1997 / Revised version: 19 January 1998     

Changes in free amino acids and biogenic amines of Egyptian salted-fermented fish (Feseekh) during ripening and storage

The aim of this study was to investigate changes in the formation of amino acids and biogenic amines in Egyptian salted-fermented fish (Feseekh) during ripening (20 days) and storage (40–60 days). The total concentration of free amino acids increased from 8 (dry weight; DW) to 72 g/kg (DW) after 60 days of storage. The predominant free amino acids were leucine, glutamic acid, lysine, alanine, valine, aspartic acid, isoleucine and citrulline. Their concentrations accounted for 68% of the total concentration of amino acids after 60 days. The total contents of biogenic amines ranged from 84 to 1633 mg/kg (DW) during the investigated period. Cadaverine was the major amine detected in Feseekh at all sampling stages and its concentration varied between 21 and 997 mg/kg (DW). The histamine content (211 mg/kg DW) only exceeded the maximum tolerance level (200 mg/kg) after 60 days. It could be concluded that Feseekh can be consumed without any health risks between 20 and 40 days but it can be hazardous after 60 days due to the biogenic amine content.     

Application and assessment of extruded edible casings manufactured from pectin and gelatin/sodium alginate blends for use with breakfast pork sausage

Casings formed from pectin (PN) containing 2.5% and 5% corn oil (CO) and olive oil (OO) and gelatine/sodium alginate blends (GSAB) containing 2.5% CO and OO respectively were used for sausage manufacture. Mechanical properties and water content of casings were assessed prior to application. Following sausage manufacture, product quality and shelf-life evaluation were assessed in terms of sensory attributes, instrumental colour, moisture loss and lipid oxidation. All manufactured casings were of good quality and initially produced intact and stable sausage products. However, with time, shrinkage of products occurred where GSAB casings were used. Sensory analysis of sausages showed that PN casings were more preferred to GSAB casings for sausage manufacture. CIE colour analysis supported sensory evaluation. Water losses from sausages using GSAB casings were lower compared to sausages using PN casings due to GSAB casings having higher ability to trap and absorb water compared to PN casings. Lipid oxidation developed over time for all sausage products, however, sausages manufactured using GSAB casings containing both CO and OO at 2.5% had better oxygen barrier properties compared to sausages manufactured using PN containing the same concentration of emulsified oils. Sausages manufactured using casings containing OO were more prone to lipid oxidation than those using CO. Importantly, sausages manufactured using PN casings containing 5.0% CO were extremely stable to lipid oxidation over a six day storage period and significantly, were <1 on the TBARS numbers scale.     

The effect of free fatty acids on the odour of pork investigated by sensory profiling and GC-O-MS

The precursors for fried flavour in pork include fatty acids, carbohydrates and amino acids. The aim of this study was to investigate the effect of free fatty acids on the odour of a pork model system and to identify important aroma compounds detected by GC-O. The odour of heat-treated minced pork to which a free fatty acid had been added was assessed by a sensory panel. The following fatty acids were compared with a control meat sample: C18:1, C18:2ω6, C18:3ω3, C18:3ω6, C20:4ω6 and C22:6ω3. The fatty acids were added at either 40 or 100 times the natural level present in the minced pork. The addition of fatty acids reduced the intensity of the meaty odour. C18:2ω6 resulted in an oily odour, while C18:3ω3 and C22:6ω3 resulted in a fishy odour. The effect of C18:1, C18:3ω6 and C20:4ω6 on the odour was smaller. An aroma analysis was performed by GC-O-MS, using eight panellists, on a control meat sample and on meat samples after addition of C18:2ω6, C18:3ω3 and C22:6ω3. Sixty-two odour-active areas were detected. An underlying compound was identified in 38 areas. A large number of long-chain aldehydes, alcohols and ketones were detected in the sample to which C18:2ω6 had been added, and this might explain the oily odour of these samples. Especially 1-penten-3-ol was detected in the samples to which C18:3ω3 and C22:6ω3 had been added, and this might explain the fishy odour of these samples.     

Prevalence of biogenic amines during ripening of a traditional dry fermented pork sausage and its relation to the amount of sodium chloride added

The presence of biogenic amines (BA) along the processing stages and storage period of "Painho de Portalegre" and its relationship with the NaCl concentration on their levels were evaluated. Total BA concentration of current "Painho de Portalegre" dry fermented sausage increased (P<0.001) with drying/smoking processing time, attaining 655mgkg(-1) dry matter (DM) at day 6, a level about six times higher than that obtained in seasoned raw material mixtures before casing stuffing (115mgkg(-1)DM). Between day 30 and 40 in the drying/smoking house, that amount increased 20-fold (2500mgkg(-1) DM) over the initial concentration. After one month of storage under vacuum at room temperature, the concentration decreased by almost half to 1561mgkg(-1)DM. Excluding tyramine, the other BA were already present in the minced raw materials. However the sum of cadaverine, putrescine, histamine and tyramine, was well below 5mgkg(-1) proposed as BA limit for meat of high hygienic quality. Cadaverine was the most concentrated BA at the last stage of the drying/smoking (1430-1254mgkg(-1)DM, after 30 and 40 days, respectively), almost double the concentration of putrescine (882-779mgkg(-1)DM), followed by tyramine, β-phenylethylamine and spermine (376-311, 24 and 27-23mgkg(-1)DM, respectively). Variation was detected among production batches, possibly due to poor control of the processing conditions in traditional manufactures and the effects of the prevailing weather conditions. A higher salt concentration in the final product, 6% compared to 3%, led to a significant reduction in the BA level (P<0.001). This difference was particularly relevant in the early stage of the drying/smoking phase, during which the greatest microbial development mainly occurred in relation to cadaverine, β-phenylethylamine, putrescine and tyramine levels.     

Determination of fatty acid composition and total trans fatty acids of Turkish biscuits by capillary gas-liquid chromatography

 In this research, fatty acid composition and total trans fatty acid contents of six types of biscuit produced by four different Turkish companies were determined by capillary gas-liquid chromatography. Total fat contents of the biscuit samples ranged between 8.5% and 26.0%. The highest fat content was determined in sesame biscuits (average 24.4%) and the lowest in petit beurre biscuits (average 13.5%). Total fat contents varied even for the same type of biscuit as a result of the use of different recipes by each company. The major fatty acids in the samples were C_16 : 0, C_18 : 0, trans C_18 : 1, C_18 : 1, trans C_18 : 2 and C_18 : 2. Depending on the biscuit type, total unsaturated fatty acid contents were between 52.1% and 72.8%. The ranges of total trans fatty acid contents in biscuit types were petit beurre 1.9–29.0%, sesame 15.0–23.1%, baby 3.0–30.5%, oat 17.6–22.4%, cocoa 1.5–22.9% and finger 1.0–24.7%. It is clear from the results that the percentage of trans fatty acids in the total fat content is significant because of the use of hydrogenated vegetable oils in biscuit production. Received: 26 July 1999 / Revised version: 9 September 1999     

Effect of tiger nut fibre addition on the quality and safety of a dry-cured pork sausage (“Chorizo”) during the dry-curing process

There is a growing interest in the revalorization of co-products from the food industry. Co-products from tiger nuts (Cyperus esculentus) milk production are a suitable fibre source. “Chorizo” is the most popular dry-cured meat product in Spain. The aim of this work was to study the effect of the tiger nut fibre addition (0, 5, and 7.5%) on the quality (composition, physicochemical, and sensorial properties) and safety (oxidation and microbial quality) of a Spanish dry-cured sausage, during the 28 days of its dry-curing process. Tiger nut fibre (TNF) addition decreased fat and increased moisture content. The addition of TNF significantly increased (p < 0.05) the total dietary fibre content of “Chorizo”. Lightness (L*), yellowness (b*) and redness index (a*/b*) were significantly (p < 0.05) affected by the fibre content. The addition of 5% and 7.5% TNF to chorizo provided rich fibre and a healthier product. Although there were slight changes in the physicochemical properties, its quality (traditional characteristics) and its safety remained.     

Bound sulphadimidine residues in raw fermented sausage: release under acidic conditions and bioavailability in rats

 Sulphadimidine (SDM), a drug frequently administered to pigs, is partially converted into other compounds by processing meat to produce raw, fermented sausage. With the aid of ¹⁴C-labelled SDM, evidence was obtained that part of the radioactive matter was covalently bound to the matrix. Part of these bound residues could be released in vitro by 4 M HCl at 21  °C or by 0.024 M HCl at 37  °C. Female rats were also able to release bound SDM residues and to excrete these in their urine, in amounts approaching those obtained by treatment with 4 M HCl. Both the parent compound and its main metabolite, N ⁴-acetyl-SDM, were observed in the urine of rats. Received: 29 December 1997 / Revised version: 20 February 1998     

Fatty acid and volatile compounds from salami manufactured with yerba mate (Ilex paraguariensis) extract and pork back fat and meat from pigs fed on diets with partial replacement of maize with rice bran

Four batches of salami were manufactured. Back fat and meat from pigs fed on diets with maize or maize partially substituted with rice bran (maize/rice bran, 62/38, w/w) were used to prepare two different batches, M and M/RB, respectively. The other two batches (M-YM or M/RB-YM) were prepared as batch M or M/RB, added a yerba mate (Ilex paraguariensis) extract. Salamis did not show differences in percentual general composition, texture analysis or sensory features. The TBAR values were affected by the storage time. The use of yerba mate extract controlled the lipid oxidation.     

Significance of fat supplemented diets on pork quality - Connections between specific fatty acids and sensory attributes of pork

The influence of two diets with different fatty acid compositions has been studied with regard to overall pork quality and significance of specific fatty acids on sensory attributes in fried chops and oven roasts. Twenty castrates and 20 females were in a balanced experimental set-up fed with a standard diet supplemented with α-tocopherol (200mg/kg feed) where the fat source was either 3% of palm oil or 3% rapeseed oil. After slaughter, despite differences in lipid composition and sensory attributes, no significant difference in overall meat quality parameters and flavour precursors was found. Comparison of the two diets showed that supplementation with rapeseed oil resulted in a significantly higher content of C18:3n-3 (polar lipid (PL), neutral lipid (NL)), C18:2n-6c (NL) and C20:2 (NL) in LD and C18:1n-9c, C18:2n-6c, C18:3n-3, C20:3n-3, C22:5n-3 in backfat, while supplementation with palm oil resulted in a higher content of C16:0 (NL), C16:1 (PL), C18:1n-9t (NL) in LD and C16:0, C17:0, C18:0, C16:1, C20:4n-6 in backfat. A positive and significant correlation between the contents of C18:2n-6c, C20:3n-6 in the PL fraction and the sensory attributes fried meat odour and sweet odour were found in fried pork chops from female pigs. Likewise, positive correlations were seen between the content of C18:1n-9c in the PL fraction and sensory attributes such as sourish odour, piggy odour and piggy flavour in whole oven roasts. These data substantiate the view that specific fatty acids in the PL fraction influences flavour attributes in pork.     

Evolution of amino acids and biogenic amines throughout storage in sausages made of horse,beef and turkey meats

The changes in concentration of free amino acids and biogenic amines, along 28 d of storage at 4 °C, were monitored in a wide range of European ripened sausages manufactured from horse, beef and turkey meats. Generally speaking, both chemical families became more concentrated with elapsing time – but rather distinct patterns were followed in each meat type: total free amino acids increased by 13-fold in the case of horse sausages, and 5-fold in the case of beef sausages, but decreased to one third in the case of turkey sausages; and total biogenic amines attained 730 mg/kg in turkey sausages, 500 mg/kg in beef sausages and 130 mg/kg in horse sausages by 28 d of refrigerated storage. For putrescine, maximum levels of 285 mg/kg were attained in turkey and 278 mg/kg in beef sausages; for cadaverine, maximum levels of 6 mg/kg in turkey and 9 mg/kg in beef; and for histamine, maximum levels of 263 mg/kg in turkey and 26 mg/kg in beef. Hence, public safety concerns may be raised in the case of turkey sausages.     

Fatty acid profiles of commercially important fish species from the Mediterranean, Aegean and Black Seas

The fat content and fatty acid compositions in the flesh of eight commercially important fish species from the seas of Turkey were evaluated. The fatty acid compositions of wild fish species ranged from 25.5% to 38.7% saturated (SFA), 13.2–27.0% monounsaturated (MUFAs) and 24.8–46.4% polyunsaturated acids (PUFAs). Among them, those occurring in the highest proportions were myristic acid (C14:0, 1.70–10.9%), palmitic acid (C16:0, 15.5–20.5%), palmitoleic acid (C16:1, 2.86–17.0%), stearic acid (C18:0, 3.32–8.18%), oleic acid (C18:1n9 cis, 6.11–20.8%), linoleic acid (C18:2n6, 0.93–4.03%), octadecatetraenoic acid (C18:4n3, 0.02–4.55%), cis-5, 8, 11, 14, 17-eicosapentaenoic acid (EPA, C20:5n3, 4.74–11.7%) and cis-4, 7, 10, 13, 16, 19-docosahexaenoic acid (DHA, C22:6n3, 7.69–36.2%). The proportions of PUFAs-n3 (ranging from 21.7 for mullet to 43.7 for scad) were higher than those of PUFAs-n6 (ranging from 1.24 for bogue to 4.34 for red scorpion fish). EPA and DHA were high in all fish species, increasing the value of these fish species.     

Fatty acids in muscles and liver of Tunisian wild and farmed gilthead sea bream, Sparus aurata

The total fat content and the fatty acids profile were analysed in the dorsal and ventral muscles and in the liver from wild and farmed gilthead sea bream (Sparus aurata). The amount of fish lipid was higher in farmed than in wild fish in all studied samples and the highest level of all was observed in liver. It was noted that, among all the samples studied for saturated fatty acids (SFA) and Monounsaturated fatty acids (MUFA), whether farmed or wild, palmitic (C16:0) and oleic (C18:1 n − 9) acids were the principal saturated and monounsaturated fatty acids. The results showed that farmed fish contained a higher level of n − 3 polyunsaturated fatty acids (PUFA), particularly docosahexaenoic acids (DHA) and eicosapentaenoic acids (EPA), whereas wild fish contained a higher level of n − 6 PUFA. Arachidonic acid (C20:4 n − 6) was the primary n − 6 PUFA in wild fish whereas in farmed fish, linoleic acid (C18:2 n − 6) was the major n − 6 PUFA. Farmed fish were characterized by higher n − 3/n − 6 ratio for all samples studied, due to the abundance of n − 3 PUFA, particularly DHA.