Dry fermented sausages elaborated with lipase from Candida cylindracea. Comparison with traditional formulations

The addition of microbial lipase to fermented sausages was studied. A sausage with lipase from Candida cylindracea and a control sausage with starter (Lactobacillus plantarum and Staphylococcus carnosus) were produced in a pilot plant. The acidity value and the amounts of the different free fatty acids (FFA) showed a higher intensity of lipolytic activity in sausages with lipase than in sausages with starter. In sausages with lipase, the percentage of saturated FFA was greater and that of polyunsaturated FFA was lower than in sausage with starter. Mono-unsaturated FFA percentage was similar in both sausages. TBA and peroxide values indicated that the increase of FFA produced by lipase action did not increase the rancidity. A slight increase in acetic, propionic and butyric acids was observed in sausage with lipase but this was not sufficient to develop excessive acidity in the product.     

浓缩型冻干发酵剂在鸭肉发酵香肠中的应用

将浓缩型冻干发酵剂应用于鸭肉发酵香肠中,对比液体发酵剂和自然发酵对香肠发酵过程中的影响。结果表明：接种冻干发酵剂的香肠48 h内pH值降到5.3以下,能够快速发酵产酸达到发酵香肠安全控制范围,且水分含量呈下降趋势,发酵末期降到30%左右;对各处理组鸭肉香肠的质构进行分析比较,接种冻干发酵剂处理组（S2处理组）以及液体发酵剂（L2处理组）的香肠硬度、弹性和咀嚼性均显著（P＜0.05）高于自然发酵（对照组）;此外,香肠发酵过程中酸价呈上升趋势,过氧化值先上升后下降,各处理组差异不显著（P＞0.05）,推断内源性脂酶比微生物发酵剂产生的脂酶发挥更大作用;各类型脂肪酸占总游离脂肪酸的比例大小顺序为：饱和脂肪酸＞单不饱和脂肪酸＞多不饱和脂肪酸,接种发酵剂的处理组游离脂肪酸总量显著高于对照组（P＜0.05）,表明发酵剂的添加对游离脂肪酸的释放起到一定促进作用,在一定程度上丰富了香肠风味的前体物质。     

Lipolysis in dry cured sausages as affected by processing conditions

Changes of phospholipids and free fatty acids during fermentation and ripening steps of the Spanish dry cured sausage ('salchichón') process have been analyzed by studying the effects of manufacturing conditions; namely starter addition, pre-ripening and drying temperature. Phospholipid concentration of all types of samples considered (with or without starter, preripened or not) showed no important changes during fermentation, but different behaviour was observed during ripening in relation to sample type and drying temperature. At 8 °C concentrations did not change in sausages without starter and suffered a moderate decrease in samples with starter. At 16 °C the decrease was pronounced in samples without starter and much more in those with starter. Pre-ripening had no effect on phospholipid concentration. Free fatty acids increase slightly with pre-ripening, but during fermentation pre-ripened samples showed no more variation, whereas in non-preripened samples an important increase was observed. These results were similar in samples with and without starter. During the ripening step, samples with starter dried at 8 °C showed a higher increase of free fatty acids than those without starter, with no influence of the pre-ripening. At 16 °C all samples showed a higher increase than any sample dried at 8 °C. The maximum was found with non-preripened samples without starter and the minimum with pre-ripened ones, also without starter. Sausages with starter showed an intermediate increase with no effect of pre-ripening.     

Lipid Fractions of Dry Fermented Sausages Change when Starter Culture and/or Aspergillus Lipase are Added

Six levels of Aspergillus sp. lipase were evaluated and 0.400u/g was selected. A sausage with a starter culture (Lactobacillus plantarum (10%)+Staphylococcus carnosus (90%)), one with lipase and one with both starter culture and lipase were produced in a pilot plant. A lower amount of Micrococcaceae was found in sausages without starter culture. Total FFA quantity at the 15th day was higher in sausages with lipase. Higher amounts of acetic, propionic and butyric acids were found in sausages with both lipase and starter culture. Odor intensity had slightly higher scores in sausages with added lipase.     

微生物酶与肉组织酶对干发酵香肠中游离脂肪酸的影响

以戊糖乳杆菌31-1和木糖葡萄球菌为发酵剂生产干发酵香肠,就发酵剂对干发酵香肠成熟过程中游离脂肪酸的影响进行了研究。研究结果表明,在灌肠后的1周内,脂肪的水解主要是由组织酶引起的,微生物对脂肪微弱的水解能力主要表现在干发酵香肠成熟的后期,并且发酵剂不能改变发酵香肠中游离脂肪酸的变化模式。     

Effect of the use of autochthonous Lactobacillus curvatus, Lactobacillus plantarum and Staphylococcus xylosus strains on microbiological and biochemical properties of the Sardinian fermented sausage

In this study, a starter culture was tentatively made by testing autochthonous Lactobacillus and Staphylococcus strains, isolated from traditional ‘Salsiccia Sarda’ sausage. Three sausage-making trials were carried out using an association of Staphylococcus xylosus + Lactobacillus curvatus (A), Staphylococcus xylosus + Lactobacillus plantarum (B), and Lactobacillus plantarum alone (C). Microbiological profiles, free amino acids, biogenic amines, and free fatty acids were evaluated after 21 days of ripening. Sausages A and B showed the highest number of lactic acid bacteria that produced a rapid acidification of substrates and reduced the number of spoilage microorganisms. Sausages made with L. plantarum alone or together with S. xylosus had the highest content of free amino acids, whereas the one produced with S. xylosus + L. curvatus showed the lowest content of total biogenic amines and best acceptance score. No significant differences among samples were found as to the free fatty acids concentration.     

Proteolytic and lipolytic starter cultures and their effect on traditional fermented sausages ripening and sensory traits

In this study, three starter formulations including Lactobacillus curvatus and Staphylococcus xylosus strains selected in vitro on the basis of their lipolytic and proteolytic activities were employed for the manufacture of traditional fermented sausages of southern Italy. Microbial population, proteolysis, lipolysis, changes in free amino acids (FAA) and free fatty acids (FFA) and development of characteristic taste and flavor of the final product were investigated. Proteolysis and lipolysis were observed in sausages inoculated with proteolytic and lipolytic S. xylosus coupled with L. curvatus, while the sausage started with only S. xylosus without lactobacilli was identical to the non-inoculated control, indicating that the proteolysis could be due to both microbial activity and endogenous proteases activated by the decrease in pH. The statistical analysis applied to the instrumental and sensory data showed that there was an effect of the starter used on the characteristics of the sausage obtained. In particular, the control samples showed very close features different from the sausages obtained by adding starter cultures. Finally, analyzing the sensory parameters the sausages ripened without starter addition and those started without the L. curvatus AVL3 showed similar features indicating an influence of the presence of the lactobacilli on the final organoleptic quality of the sausages. An appropriate choice of a combination of strains in a starter formulation is fundamental to obtain products of the expected quality.     

多菌发酵对如式香肠营养与风味的影响

以米酒乳杆菌L04、耳式葡萄球菌C131 和德巴利汉逊酵母Y163 为复合发酵剂研制一种新型如式香肠,以不接菌的自然发酵样品为对照,测定其游离氨基酸与脂肪酸、挥发性风味物含量。结果显示：优配方组起始菌数构成比L04:C131:Y163 为1:2:1 的氨基酸总量、必需氨基酸含量分别比对照组提高103%、54%;亚油酸、花生四烯酸分别提高59%、45%;脂肪酸构成饱和脂肪酸(SFA):单不饱和脂肪酸(MUFA):多不饱和脂肪酸(PUFA)之比由1.0:1.1:0.4 优化为1.0:1.2:0.5;醛类、酮类香气物质分别提高62.07%、13.96%,理想效果归于C131 作用以及与其他菌的巧妙搭配。     

烘烤中广式腊肠挥发性风味成分及脂质的变化

研究广式腊肠的风味形成机理,探索烘烤过程中广式腊肠的挥发性风味物质、游离脂肪酸、硫代巴比妥酸(TBA)值和羰基值的变化规律。结果显示,酯类和醇类化合物是烘烤过程中广式腊肠挥发性风味物质的主体成分;各类游离脂肪酸总含量在烘烤过程中呈增加的趋势,其中不饱和脂肪酸的质量分数在烘烤至32h 后呈下降的趋势,而饱和脂肪酸的质量分数则略有上升;TBA 值和羰基值的变化显著,但在广式腊肠烘烤过程中没有发现大量的醛、酮类物质存在,这可能与脂肪酸进一步与醇反应生成酯有关。所以,广式腊肠在烘烤过程中脂肪不断氧化水解,且氧化程度逐渐加深,酯类化合物不断增加。     

Quality and ripening changes of Ras cheese made by direct acidification

Trials were carried out to produce Ras cheese of good quality without the use of starter. Cheese was made from pasteurized cow's milk acidified with lactic acid or citric acid to pH 5.8 alone or coupled with mixing the curd with glucono δ lactone (4.5 g/kg curd). Control cheese was made from milk ripened with a starter culture of S. lactis. Resultant cheeses showed poor body and texture, weak flavour intensity and low levels of soluble nitrogen compounds and free volatile fatty acids. Incorporation into the cheese curd of mixtures containing Fromase 100 (fungal protease) and Piccantase B (fungal lipase) or Fromase 100 and Capalase K (animal lipase) enhanced flavour intensity, improved body characteristics and accelerated the formation of both soluble nitrogen compounds and free volatile fatty acids. The organoleptic properties of the experimental cheeses with added enzymes were comparable to those of the control cheese.     

外源脂肪酶改善腊鱼品质

该研究以鲢鱼为主要原料,植物乳杆菌、木糖葡萄球菌和酿酒酵母为混合发酵剂,发酵期间加入外源脂肪酶制作腊鱼产品。通过分析腊鱼的游离脂肪酸、pH值、白度、质构,以及结合感官评价结果探究发酵温度、脂肪酶添加量和添加时间对腊鱼品质的影响。结果表明,脂肪酶可有效改善腊鱼的品质。具体方法为:鲢鱼块接入发酵剂在20℃下发酵27 h后,加入0.04%(以鱼肉计)的外源脂肪酶(22000 U),继续在20℃下发酵45 h,然后经冲洗、烘干(30℃,3 h)、成熟(15℃,5 d)得到最终产品。与未加酶产品相比,加酶后发酵腊鱼的游离脂肪酸、pH发生较大改变,产品的色、香、味均有明显改善,说明外源脂肪酶可通过影响腊鱼在发酵过程中的脂肪代谢达到提升产品品质的目的。     

Effect of a food-grade enzyme preparation fromAspergillus oryzae on free fatty acid release in Manchego-type cheese from ovine and bovine milk

The addition of 50 mg Flavor Age (blend of lipase, proteinases and peptidases fromAspergillus oryzae) per kilogram of mixed ovine plus bovine milk for the manufacture of Manchego-type cheese caused the release of abundant free fatty acids (FFA), especially the short-chain fatty acids (C₄ to C₁₀). The effect accentuated with ripening time, the cheeses reaching a level of FFA around 2% at 120 days. The high concentration of FFA could have partially inhibited the growth of starter culture, as can be deduced from the higher residual lactose content of enzyme-treated cheeses. The results are compared and related to those obtained in a previous study on proteolysis and flavour development by the same enzyme preparation. They suggest that in the case of Man-chego-type cheese the liberation of FFA, although necessary, could be less important for flavour enhancement than the production of free amino acids.     

直投式发酵剂制备的哈尔滨风干肠在成熟过程中的理化及微生物特性变化

采用三种由自然发酵分离鉴定出的微生物,按一定比例混合制备复合发酵剂,将其用于哈尔滨风干肠中,研究其对风干肠的理化性质、微生物变化和游离氨基酸含量的影响。实验分为三组,分别为对照组,添加普通发酵剂组和添加直投式发酵剂组。结果表明:添加发酵剂的风干肠pH明显低于对照组,且添加直投式发酵剂的pH最低(P<0.05);添加发酵剂会使产品的游离氨基酸含量显著提高(P<0.05)、感官品质也较好(P<0.05),而各组水分活度变化差异不明显,这说明直投式发酵剂具有很好的活力和发酵性能,能够显著提高风干肠的质量,缩短发酵时间。     

Changes in selected biochemical and sensory parameters as affected by the superficial inoculation of Penicillium camemberti on dry fermented sausages

An atoxigenic strain of Penicillium camemberti was superficially inoculated on fermented sausages in an attempt to improve their sensory properties. The growth of this mould on the surface of the sausages resulted in an intense proteolysis and lipolysis, which caused an increase in the concentration of free amino acids, free fatty acids (FFA) and volatile compounds. Many of these were derived from amino acid catabolism and were responsible for the "ripened flavour", i.e. branched aldehydes and the corresponding alcohols, acids and esters. The development of the fungal mycelia on the surface of the sausages also protected lipids from oxidation, resulting in both lower 2-thiobarbituric acid (TBARS) values and lipid oxidation-derived compounds, such as aliphatic aldehydes and alcohols. The sensory analysis of superficially inoculated sausages showed clear improvements in odour and flavour and, as a consequence, in the overall quality of the sausages. Therefore, this strain is proposed as a potential starter culture for dry fermented sausage production.     

Pre-inoculation enrichment procedure enhances the performance of bacteriocinogenic Lactococcus lactis meat starter culture

Sodium nitrite and sodium chloride may inhibit growth and bacteriocinogenesis of protective starter cultures. To reduce sensitivity of a lacticin 3147-producing starter culture to nitrite, prior to production of salami, Lactococcus lactis DPC 4275 was placed in a number of pre-inoculation treatments, containing (a) 1% glucose, (b) 2.5 ppm manganese (Mn), (c) 250 ppm magnesium (Mg), (d) 2.5 ppm manganese + 250 ppm magnesium (Mn + Mg), and held at ambient temperature for 30 min and 4 degrees C for 2 h. The growth, pH reduction, and bacteriocin production was monitored in beaker sausage over a period of 10 days at 28 degrees C, corresponding to typical salami production time, and compared to untreated starter culture. The effect of 1% tryptone and inoculum level on growth and bacteriocin production was also determined. Challenge tests were performed using Listeria innocua DPC 1770 and Staphylococcus aureus MMPR3 as target strains. All treatments gave a significantly higher (P < 0.05) initial starter level than the untreated starter. Beaker sausage inoculated with either low (10(7)) or high (10(9)) levels of starter culture, treated with Mn + Mg reached significantly (P < 0.05) higher levels by day 10 than other treatments. Trends indicate that Mn + Mg also gave best pH reduction in sausage containing the low-level starter culture, sausage and significantly lower (P < 0.05) values for sausage produced with higher inoculum. Bacteriocin production was also higher in starter culture treated with Mn, or glucose. Pre-treatment with Mg gave a 2-fold increase in bacteriocin, the addition of Mn augmenting this increase further. The incorporation of tryptone gave no additional effect. In beaker sausage, both L. innocua and S. aureus populations showed significant reductions (P < 0.05) in the presence of the bacteriocinogenic strain compared to a non-bacteriocinogenic control strain.     

混合菌种干法发酵生产中式香肠及产品品质研究

本文采用不同的混合菌种木糖葡萄球菌-12和戊糖片球菌-ATCC33316(CHS-SP)、木糖葡萄球菌-12和干酪乳杆菌干酪亚种-1．001(CHS-SL)作为发酵剂，并以无引发剂组(CHS-CONT)作对照研制了3批不同的中式干发酵香肠产品，并对各产品的理化性质、微生物学性质及感官品质进行了研究。结果显示：产品水分活度0．8～0．82，pH4．85～4．98，残留NaNO23．84～7．11mg／kg，挥发性总氮(TVBN)17．77～19．05mg／100g；17种游离氨基酸中，谷氨酸和精氨酸含量较大，半胱氨酸含量甚微；与对照组相比，混合菌种发酵显著提高了香肠中总游离氨基酸含量，对产品的色泽和质构有明显的改善，并能有效地抑制产品中致病肠道杆菌、酵母菌以及霉菌的生长，但对总平板数没有影响；感官评价表明CHS-SL组发酵香肠品质最佳，对照组CHS-CONT最差。     

Dry fermented sausages made with a protease from Aspergillus oryzae and/or a starter culture

Sausages with a starter culture (Lactobacillus plantarum + Staphylococcus carnosus), a protease (Fungal Protease from Solvay Enzymes) and both enzyme/starter were produced from the same raw matter under the same conditions for 15 days of ripening. The lowest pH values were found in Fungal/starter sausages. Significantly higher amounts of free amino acids (FAA) were seen in sausages containing enzyme from the 3rd day of ripening, whereas amino acids from peptides (PAA) were significantly higher only after 15 days of ripening. Enzyme addition gave rise to changes in 10 of the 15 FAA analyzed. Histidine was the main amino acid from the peptide fraction that increased in both sausages containing added enzyme. Although trained panelists detected some sensorial benefits in the sausages with added enzyme, the effects were not as marked as might have been expected.     

成熟时间对羊肉发酵香肠品质及风味的影响

通过添加清酒乳杆菌及木糖葡萄球菌制作发酵羊肉香肠,采用气相色谱-质谱(GC-MS)联用技术测定不同成熟时间(0,3,4,5,6 d)香肠脂肪酸及风味组成,探究不同成熟时间对羊肉发酵香肠食用品质及风味累积的影响,旨在确定香肠成熟最佳时间.结果表明:随着成熟时间的延长,香肠pH值、水分活度(aw)显著(P<0.05)下降,...     

糖添加量对广式腊肠脂质降解的影响

研究了不同糖添加量(3%、6%、9%、12%,m/m)对广式腊肠脂质降解的影响规律。将广式腊肠中瘦肉和肥丁分别进行研究,利用固相萃取技术将脂质分为中性脂肪、磷脂和游离脂肪酸,采用气质联用分析中性脂肪和磷脂的脂肪酸组成、游离脂肪酸的组成及含量。结果表明:磷脂是广式腊肠中脂质降解的主要成分,中性脂肪也对游离脂肪酸的释放有一定作用;瘦肉部分的脂质是腊肠脂质降解的主要部分。糖添加量对中性脂肪和磷脂的多不饱和脂肪酸组成比例具有显著影响,糖添加量低时多不饱和脂肪酸组成比例高,尤其是对瘦肉部分的磷脂影响最为显著,糖添加量为12%时其比例为17.88%,而添加量为6%和3%时分别变为36.70%和33.94%;游离脂肪酸含量随糖添加量的减少而降低,表明糖对腊肠的脂质降解具有一定促进作用。由于多不饱和脂肪酸极易氧化导致其组成比例较低。     

Enhancement of Release of Short-Chain Fatty Acids from Milk Fat with Immobilized Microbial Lipase

Candida cylindracea or Rhizopus arrhizus lipase was entrapped in polymer gels prepared from photo-cross-linkable resin prepolymers. The immobilized enzyme was used in milk fat hydrolysis and effective in enhancing the release of short-chain fatty acids compared with free enzyme. The molar percentage of short-chain fatty acids (butyric acid to capric acid) released in the reaction increased significantly after enzyme immobilization. The gel composed of hydrophobic long-chain prepolymer gave the highest increase, with 5.9-fold and 4.5-fold increases for C. cylindracea and R. arrhizus lipase, respectively. Difference in substrate diffusion rate between milk fat triglycerides may be responsible for this behavior.