COLOR DEVELOPMENT DURING NATURAL FERMENTATION AND CHEMICAL ACIDIFICATION OF SALAMI-TYPE PRODUCTS

Physico-chemical Properties and Sensorial Appreciation of a New Fermented Probiotic Beverage Enriched with Pea and Rice Proteins

OBJECTIVES

The purpose of this study was to evaluate the physico-chemical stability, the sensorial properties, and the microbial quality of a fermented beverage enriched with pea and rice proteins (PRF) during storage at 4 °C. To investigate the effect of the protein enrichment and fermentation, the PRF beverage quality was compared with non-fermented and non-enriched beverages.

METHODS

The beverage was supplemented with a 50/50 mixture of pea and rice protein concentrate to 13% concentration. Following inoculation with 108 CFU/mL of lactic acid bacteria, it was incubated at 37 °C for 14 h.

RESULTS

Results showed that the enrichment with protein induced an increase in pH, titratable acidity and viscosity of the PR products, while the fermentation led to a decrease of pH and viscosity. However, a significant increase of the viscosity of PRF from 39 to 57 cP was observed during the 143 days of storage (P ≤ 0.05). The PRF beverage contained significantly more peptides < 200 Da than the non-fermented one (PRNF) and these small peptides were also released during the storage. Despite the physico-chemical modifications, the sensorial properties of the PRF product were appreciated over the storage, particularly for the texture. Furthermore, the beverage maintained a high concentration of viable probiotics during the entire storage with 8.4 log colony form unit (CFU)/mL after 143 days.

CONCLUSION

Applying probiotics and the mixture of rice and pea proteins in the fermented beverage can enhance nutritional and nutraceutical value of the product.

Effects of Lemon Extract Powder and Vinegar Powder on the Quality Properties of Naturally Cured Sausages with White Kimchi Powder

This study investigated the effects of lemon extract powder and vinegar powder on the physicochemical and microbiological characteristics of pork sausages naturally cured using white kimchi powder during storage for 30 days. Six batches were included: control (0.01% sodium nitrite and 0.05% sodium ascorbate); treatment 1 (0.3% white kimchi powder and 0.5% lemon extract powder); treatment 2 (0.3% white kimchi powder and 1.0% lemon extract powder); treatment 3 (0.3% white kimchi powder and 0.5% vinegar powder); treatment 4 (0.3% white kimchi powder and 1.0% vinegar powder); and treatment 5 (0.3% white kimchi powder, 0.5% lemon extract powder, and 0.5% vinegar powder). Treatment 2 had significantly lower pH values and higher cooking loss than the other batches (p<0.05). Treatments 1, 2, and 5 had similar (p>0.05) CIE a* as the control, while treatments 3 and 4 showed significantly lower values (p<0.05). The residual nitrite content in naturally cured products was lower than the control (p<0.05), while treatments 1 and 2 showed significantly higher nitrosyl hemochrome content and curing efficiency (p<0.05). TBARS values were similar for all treatments and the control (p>0.05). Treatments 1 and 2 showed significantly reduced aerobic plate counts (APC; p<0.05) than the control and other treatments. However, across all batches, TBARS values and APC significantly increased during storage (p<0.05). Our results suggest that lemon extract powder, rather than vinegar powder, may offer a promising alternative for supplementing the functions of nitrite in naturally cured sausages.

Effect of starter culture type, cooking process and storage time at -18 °C on chemical, color and microbiological qualities of fermented sucuk doner kebab

The aim of this study was to produce fermented sucuk doner kebab and investigate the effects of starter culture type, heat treatment (82 °C) and storage time (0, 30, 90, 180 days) at -18 °C on pH, total acidity, thiobarbituric acid, residual nitrite-nitrate, color and microbiological quality. In this study, three types of starter cultures were used. These were commercial starter culture, L.sakei + S.xylosus + L.curvatus, isolated starter culture (1), L.sakei + S.xylosus + L.curvatus and isolated starter culture (2), L.sakei + S.xylosus + L.plantarum. There was also control product which contains no starter culture. The major pH decrease was observed in samples containing isolated starter cultures. Cooking and storage caused an increase in pH. Isolated starter culture was more effective than commercial starter culture in reducing residual nitrite-nitrate. Isolated starter cultures caused an increase in L* color values. The highest lactic acid bacteria count was found in sample containing commercial starter culture. Cooking was effective in inhibiting Enterobacteriaceae.

Comparison of Meat Quality Traits in Salami Added by Nitrate-free Salts or Nitrate Pickling Salt during Ripening

The intent of this study was to scrutinize the consequence of salt type [sun-dried salt, refined salt, baked salt, or nitrate pickling salt (NP)] on the physicochemical and microbiological features of salami formulated by soaking with Aspergillus spp. before ripening. The effects of nitrate-free salts added were not significant. Nitrate pickling salt samples were significantly higher in protein level, whereas those were lower in fat level during ripening (p<0.05). The pH of salamis treated with NP was higher than that of other salt treatments, while weight losses of those was lower (p<0.05). During the ripening and drying, NP produced lower extent of volatile basic nitrogen and lipid oxidation than those with other salts (p<0.05). The total aerobic population counts of NP samples revealed lower than that of other samples over the ripening time. The addition of NP in salamis produced redder sausages. The salamis containing NP found to be better physicochemical and microbiological quality attributes than the other salt types.

Effect of Quality Grade and Storage Time on the Palatability, Physicochemical and Microbial Quality of Hanwoo Striploin Beef

The effects of quality grade and storage time on physicochemical, sensory properties and microbial population of Hanwoo striploin beef were investigated. After a total of 30 Hanwoo beef were slaughtered, the cold carcasses were graded by official meat grader at 24 h postmortem. The carcasses were categorized into five groups (quality grade 1++, 1+, 1, 2, and 3) and were vacuum-packaged and stored. The samples were kept for 1, 4, 6, 8, 11, 13, 15, 18, 20, 22 and 25 d for analyses. As the quality grade was increased, moisture, protein and ash contents decreased (p<0.05). Higher quality grade corresponded with higher fat contents. The shear force values decreased with increasing quality grade and showed decreases sharply during the first 4 d (p<0.05). pH, water holding capacity, cooking loss, and volatile basic nitrogen for grade 1++ groups were lower than for grade 3 (p<0.05). CIE L* and b* values increased as increased quality grade (p<0.05). Meat color decreased until 13 d and fluctuated after 15 d of storage (p<0.05). Regarding the sensory scores, higher quality grade corresponded with higher juiciness, tenderness, flavor, fatty and palatability scores (p<0.05). Generally, increased storage time for 15 d improved sensory scores attributes. Results indicate that a high quality grade could positively influence physicochemical and sensory properties.

Effect of GdL Addition on Physico-chemical Properties of Fermented Sausages during Ripening

This study investigated the effects of glucono-δ-lactone (GdL) addition on physicochemical and microbiological characteristics of fermented sausages during ripening and drying. Five batches of sausages were produced under ripening conditions: without GdL and with 0, 0.1, 0.25, 0.5 and 0.75% of GdL addition. Samples from each treatment were taken for physicochemical and microbiological analyses on the 0, 1, 3, 5, 7, 10, 15, 20 and 25th day of ripening. Chemical analysis showed a significant decrease in moisture content of sausages with increasing amounts of GdL added (p<0.05). The moisture contents decreased, whereas the fat, protein and ash contents increased throughout ripening (p<0.05). Increasing levels of GdL caused a decrease in the pH values (p<0.05), which can have an inhibitory effect against microflora. Water holding capacity content of samples decreased with increasing GdL concentration (p<0.05). The shear force values of fermented sausages showed the highest in T4 (p<0.05). During ripening, the shear force values of sausages were increased on the 25th day compared to day 0 (p<0.05). The higher GdL level produced lighter and more yellow sausages. The addition of 0.75% GdL was effective in controlling bacteria counts. Addition of GdL in sausages resulted in the physicochemical and microbiological attributes equal to or better than no addition of GdL without any harmful effect.

Use of tocopherol extract and different nitrite sources and starter cultures in the production of organic botifarra catalana, a cooked cured sausage

This research evaluates the effects of adding a tocopherol mix (0 or 200 mg/kg), two nitrite sources (sodium nitrite or a nitrate-rich vegetable concentrate) and the use of Staphylococcus carnosus together with fermentation types that varied in temperature (12 h at 4 ℃ or 16 ℃) on different quality parameters and acceptability of cooked cured sausages after vacuum packing and storage at 4 ℃ for 120 days. In the presence of S. carnosus, residual nitrate and nitrite levels were reduced. Sausages containing vegetable concentrates and without S. carnosus resulted in higher amounts of residual nitrate and lower curing efficiency. The lowest values in redness and acceptability were observed in those sausages without starter cultures. The addition of tocopherols had no effect on oxidative status and susceptibility to oxidation. However, the highest amount of hydroperoxides was related with nitrite decreased formation. Overall, vegetable concentrates can be used as curing agents if fermentation with a nitrate-reducing starter culture is allowed.