THE EFFECT OF ADDITION OF HAZELNUT OIL ON SOME QUALITY CHARACTERISTICS OF TURKISH FERMENTED SAUSAGE (SUCUK)

The effects on chemical and physical quality of the addition of beef fat with hazelnut oil were studied in sucuk. Two sucuk formulations were prepared by the addition of 2.5 and 5% hazelnut addition in which 11.11 and 20% of beef fat was substituted with hazelnut oil. The addition of hazelnut oil increased total fat of the product that affected the chemical, physical and sensorial characteristics of products. Added hazelnut oil decreased protein content but increased free fatty acids and thiobarbituric acid reactive substances values. The formulation with 2.5% hazelnut oil, corresponding to 11.11% substitution of beef fat with hazelnut oil, was judged as similar to control.

PRACTICAL APPLICATIONS

The results suggest that the addition of hazelnut oil in the production of sucuk could give a healthier option to consumers. This study showed that substitution of animal fat with hazelnut oil in fermented sausages is a useful application to develop a functional fermented meat product. Additionally, this study indicated that the hazelnut oil was found to be a good oil in fermented sausage and opened the door for new research with a different nut.     

RESPONSE SURFACE METHODOLOGY STUDY ON THE POSSIBILITY OF NITRITE REDUCTION BY GLUCONO-δ-LACTONE AND ASCORBIC ACID IN TURKISH-TYPE FERMENTED SAUSAGE (SUCUK)

The primary goal of this study was to determine the residual nitrite-reducing effects of glucono-δ-lactone (GDL) and ascorbic acid (AA) in Turkish-type fermented sausage. Response surface methodology was used to investigate the simultaneous effects of processing variables, e.g., nitrite (0–200 mg/kg sausage), GDL (0–0.5% w/w) and AA (0–500 mg/kg sausage) on pH, moisture, residual nitrite, proteolysis, lipolysis, peroxide, yield and sensory score of the sausage. AA significantly ( P <  0.01) decreased the residual nitrite level; however, quadratic effect of AA showed an inverse effect. GDL did not produce the same effect on the residual nitrite level. The processing variables had no prominent effect on the proteolysis, lipolysis and peroxide. GDL and AA addition showed a negative effect on the yield and sensory scores of the sausages. The regression model predicted the optimum residual nitrite content to be 0.75 mg/kg. The critical values for nitrite, GDL and AA to obtain this optimum level were 147.56 mg/kg, 0.17% and 565 mg/kg, respectively.

PRACTICAL APPLICATIONS

Residual nitrite level is a major problem in the Turkish-type fermented sausage product with respect to some health concerns, residual nitrite causes a possible formation of the carcinogenic N -nitrosamines. The results of this study can be applied to reduce the residual nitrite level in sausage and to find the optimum levels of nitrite, glucono-δ-lactone and ascorbic acid levels to maintain the characteristic sausage quality properties. Based on the results, ascorbic acid can be used to reduce the residual nitrite levels in the sausage.     

EFFECTS OF NISIN AND MODIFIED ATMOSPHERE PACKAGING (MAP) ON THE QUALITY OF EMULSION‐TYPE SAUSAGE

ABSTRACT

The aim of this work was to study the effects of nisin (30 ppm) and modified atmosphere packaging (MAP) on the chemical, microbial and sensory properties of emulsion‐type sausage stored under two different atmospheres (%CO₂/%N₂/%CO/%O₂): 39.5/60/0.5/0 and 39.5/20/0.5/40. The samples were stored at 3 ± 1C for 42 days. Microbial count, values of pH, CIE L*, a* and b* color parameters, lipid oxidation, production of nitrosomyoglobin and sensory properties were assessed throughout the storage period. The data showed that nisin was able to reduce the growth of mesophilic, psychrotrophic and lactic acid bacteria. In addition, the MAP did not show any significant effects on microbial growth. However, free O₂ MAP, in combination with nisin, reduced the growth of yeast and mold. MAP could produce a stabilized red color and minimize the oxidative reactions in the samples. Packaging conditions had no significant effect on pH and sensory properties.

PRACTICAL APPLICATIONS

The results of this study confirmed that nisin can reduce the growth rate of lactic acid bacteria, psychrotrophic and mesophilic bacteria in emulsion‐type sausage, and free O₂ MAP, in combination with nisin, inhibits the growth of yeast and mold. The use of 30 ppm nisin, in combination with MAP containing 39.5% CO₂ and 0.5% CO gases, can lead to better quality preservation of the emulsion‐type sausages stored at low temperature and can extend their shelf life.     

INFLUENCE OF ANTIMICROBIAL COMPOUND(S) EXTRACTED FROM MILK FERMENTED BY STREPTOCOCCUS THERMOPHILUS ON KEEPING QUALITY OF MEAT AND MILK

The potential of a methanol-acetone (M-A) extract prepared from milk fermented by Streptococcus thermophilus in extending the shelf-life of meat and milk was investigated. In experiment I, increasing amounts (0, 0.1, 0.2 and 0.3 ml) of M-A extract with or without ascorbic acid were added to 20 g aliquots of ground beef subsequently stored at 5–7° C for 0, 3 and 6 days. Total and gramnegative bacterial counts and pH in ground beef treated with M-A extract were significantly (P<0.01) less than the corresponding values in control beef on days 3 and 6 for all dose levels tested with significant (P<0.01). In experiment II, rib-eye steaks were sprayed with H₂O or 0.1, 0.2 and 0.3 ml of M-A extract and stored at 5–7° C for 0, 3 and 6 days. The total and gram-negative bacterial counts on the surface of steaks sprayed with M-A extract were significantly (P<0.01) lower than the counts in control steaks. Also, in experiment III, inhibition of bacterial growth by M-A extract was significant (P<0.01 or 0.05) both in milk stored at either room temperature or 5–7° C. M-A extract inhibited the growth of Pseudomonas fluorescens inoculated into milk.     

INFLUENCE OF COMBINED MICROWAVE‐VACUUM DRYING ON DRYING KINETICS AND QUALITY OF DRIED TOMATO SLICES

ABSTRACT

The study investigated the influence of four microwave powers on the drying kinetics and quality of tomato slices in a microwave‐vacuum dryer at vacuum pressures of 0.04, 0.05 and 0.06 MPa. The results showed that increase in microwave‐vacuum drying conditions increased drying rates and resulted in decreased drying time from 84 to 14 min. The nonenzymatic browning index increased with microwave power whereas the overall flavor degradation was between 18.99 and 20.80%. The brightness and the yellowness of the dried tomatoes generally increased but there was a slight reduction in redness when compared with the fresh. The effective moisture diffusivity increased with microwave power and was 7.22 × 10^?9, 9.10 × 10^?9, 14.99 × 10^?9 and 25.19 × 10^?9 m²/s at respective microwave powers of 200, 300, 500 and 700 W.

PRACTICAL APPLICATIONS

Microwave‐vacuum drying is one of the advanced methods with numerous advantages including high thermal efficiency, shorter drying time and improved product quality. Tomato is the second most important vegetable with enormous health benefits, which include reduction of cholesterol, improvement of vision, maintenance of gut, lowering of hypertension, alleviation of diabetes, and prevention of urinary tract infections and gallstones. The quality of dried products obtained using the microwave‐vacuum dryer provides industries with method that can be used to enhance the quality of dried tomatoes. The dried product is a valuable ingredient in the preparation of soups and sauces, as well as in cosmetics and pharmaceutical formulations.

     

INCLUDING CHESTNUTS AND SUGAR BEET PULP IN DIETS FOR PIGS: THE EFFECTS ON THE QUALITY OF PORK MEAT AND THE SENSORY PROPERTIES OF DRY-CURED SAUSAGE (CHORIZO GALLEGO)

This research was aimed at evaluating how the inclusion of dried chestnuts and dried sugar beet pulp in diets for pigs affected the quality of pork meat and the sensory properties of dry-cured sausage ( chorizo gallego ). The meat from pigs that received a diet with chestnuts and sugar beet pulp (CBP) showed lower thiobarbituric acid values and higher water-holding capacity than meat from pigs fed a conventional diet (C). Significant differences were also observed between both batches in color parameters and fatty acid composition of the meat. In the sensory analysis of chorizo, the sausages manufactured with meat from pigs fed the CBP diet were significantly better rated than those with meat from pigs fed a C diet in appearance, odor, flavor, texture and overall score.

PRACTICAL APPLICATIONS

The inclusion of dried chestnuts and dried sugar beet pulp in diets for pigs during the fattening period allowed us to recover some of the ingredients more traditionally used in the feeding of pigs. This inclusion modifies some parameters of the resulting pork meat quality; (it decreases lipid oxidation and increases water-holding capacity and polyunsaturated fatty acid content) and also improves the sensory properties of any dry-cured product made with this pork meat.     

INFLUENCE OF CUT AND PACKAGING FILM ON SENSORY QUALITY OF FRESH-CUT BUTTERHEAD LETTUCE (LACTUCA SATIVA L., CV. WANG)

ABSTRACT

The purpose of the present work was to study the influence of cut (manual and using a sharp knife) and packaging film (bioriented polypropylene and polyolefin PD‐961) on the sensory quality of fresh‐cut butterhead lettuce stored under passive modified atmosphere at 5C. Results showed that lettuce cut by hand had a lower respiration rate and deterioration rate than those cut with a knife. This difference could be attributed to a difference in the level of wounding, which can be explained by the fact that cutting by hand caused the tear to follow the naturally weaker areas of the lettuce, leading to less tissue damage than that engendered by the use of a sharp knife.

PRACTICAL APPLICATIONS

Results suggest that lettuce leaves cut by hand showed a lower sensory deterioration rate than those cut with a sharp knife. While not industrially applicable, the cutting of lettuce by hand might be appealing to small ventures such as buffets, restaurants and catering services. The sensory analysis carried out suggests that the use of polyolefin PD‐961 is preferred over bioriented polypropylene for packaging fresh‐cut lettuce, in view of achieving a better quality of the produce.