Sodium Diacetate Research Articles

An evaluation of the effectiveness of four chemical additives on the fermentation characteristics, in vitro digestibility and aerobic stability of total mixed ration silage based on soy sauce residue.

The study aimed to compare the impact of four chemical additives on fermentation characteristics, aerobic stability and in vitro digestibility of total mixed ration (TMR) silage based on soy sauce residue. The TMR (35% soy sauce residue + 45% Napier grass + 20% concentrate) was placed into silos (10 L). The experiment followed the completely random design, treated with different chemical additives: (1) distilled water (control); (2) 0.1% potassium sorbate (SP); (3) 0.1% sodium benzoate (SS); (4) 0.5% calcium propionate (SC); (5) 0.5% sodium diacetate (SD). Total of 100 silos (5 treatments × 4 aerobic exposure days × 5 replicates) were ensiled for 60 days. After exposure to the air, the samples were analyzed for the dynamic change of fermentation parameters at 4, 9 and 15 days, and the data was analyzed as repeated measures. The content of butyric acid and ammonia nitrogen was maintained at a low level. The highest (p < 0.05) lactic acid (LA) content and the lowest (p < 0.05) pH value were measured in SP. At the first 4 days of aerobic exposure, TMR silages treated with four chemical additives were more stable relative to the control, as indicated by the low pH value and yeast counts. Furthermore, the highest (p < 0.05) LA content and the lowest (p < 0.05) pH value indicated that SP performed superior aerobic stability compared with other chemical additives. The SP shows higher (p < 0.05) 72 h cumulative gas production (GP72) and in vitro neutral detergent fiber digestibility (IVNDFD) relative to the control. In conclusion, the SP performed superior in improving fermentation characteristics, aerobic stability and in vitro digestibility of TMR silages based on soy sauce residue.

Leuconostoc gelidum Is the Major Species Responsible for the Spoilage of Cooked Sausage Packaged in a Modified Atmosphere, and Hop Extract Is the Best Inhibitor Tested.

Cooked sausages packaged in a modified atmosphere (MAP: 20% CO2, 70% N2, <0.2% O2) with evident yellow stains were analyzed. The aims of this work were to study the microbial cause of the spoilage and to evaluate different antimicrobial compounds to prevent it. Leuconostoc gelidum was identified as the primary cause of the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. Leuconostoc gelidum was the main bacteria responsible for the yellow coating in spoiled cooked sausage, as confirmed by its intentional inoculation on slices of unspoiled sausage. The yellow color was also evident during growth in the model system containing cooked sausage extract, but the colonies on MRS agar appeared white, demonstrating that the food substrate stimulated the production of the yellow pigment. The spoilage was also characterized by different volatile compounds, including ketones, ethanol, acetic acid, and ethyl acetate, found in the spoiled cooked sausage packages. These compounds explained the activity of Leuc. gelidum because they are typical of heterofermentative LAB, cultivated either on food substrates or in artificial broths. Leuc. gelidum also produced slight swelling in the spoiled packages. The efficacy of different antimicrobials was assessed in model systems composed of cooked sausage extract with the antimicrobials added at food product concentrations. The data showed that sodium lactate, sodium acetate, and a combination of sodium lactate and sodium diacetate could only slow the growth of the spoiler-they could not stop it from occurring. Conversely, hop extract inhibited Leuc. gelidum, showing a minimal inhibitory concentration (MIC) of approximately 0.008 mg CAE/mL in synthetic broth and 4 mg CAE/kg in cooked sausage slices. Adding hop extract at the MIC did not allow Leuc. gelidum growth and did not change the sensorial characteristics of the cooked sausages. To our knowledge, this is the first report of the antimicrobial activities of hop extracts against Leuc. gelidum either in vitro or in vivo.

Investigating bacteriophages as a novel multiple-hurdle measure against Campylobacter: field trials in commercial broiler plants

Campylobacter mitigation along the food production chain is considered effective for minimizing the public health burden of human campylobacteriosis. This study is the first combining different measures in a multiple-hurdle approach, using drinking water additives and feed additives in single and combined application schemes in commercial broiler plants. Broiler chickens in the study groups were naturally contaminated with Campylobacter. Application of an organic acid blend via drinking water, consisting of sodium propionate, potassium sorbate, and sodium diacetate, resulted in significant reductions of up to 4.9 log10 CFU/mL in fecal samples and in cecal samples at slaughter. The application of a phage mixture, consisting of Fletchervirus phage NCTC 12673 and Firehammervirus phage vB_CcM-LmqsCPL1/1, resulted in reductions of up to 1.1 log10 CFU/mL in fecal samples 1 day after dosing. The sole administration of curcumin via feed resulted in small and inconsistent reductions. In the group receiving a combination of all tested measures, reductions of up to 1.1 log10 CFU/mL were observed. Based on the results of our field trials, it was shown that both the sole application and the combined application of mitigation measures in primary production can reduce the Campylobacter load in broiler chickens, while no synergism could be observed.

Effect of sodium diacetate on fermentation, aerobic stability, and microbial diversity of alfalfa silage.

Alfalfa (Medicago sativa L.) is a vital source of forage protein for ruminants, yet its ensiling poses challenges due to high buffering capacity and low water-soluble carbohydrates (WSC). This study investigated the impact of sodium diacetate (SDA) on alfalfa silage quality and aerobic stability. SDA was applied at four different rates to wilted alfalfa on a fresh basis: 0g/kg, 3g/kg, 5g/kg, and 7g/kg, and silages were ensiled in laboratory-scale silos for 45days, followed by 7days of aerobic exposure. A 16S rRNA gene sequencing assay using GenomeLab™ GeXP was performed to determine the relationship between dominant isolated lactic acid bacteria species and fermentation characteristics and aerobic stability on silage. The results showed that Lentilolactobacillus brevis, Pediococcus pentosaceus and Enterococcus faecium were the most prevalent bacteria when silos were opened, whereas Weissella paramesenteroides, Bacillus cereus, B. megaterium and Bacillus spp. were most prevalent bacteria after 7days of aerobic exposure. Dry matter, pH, and WSC content were not affected by SDA, but doses above 5g/kg induced a homofermentative process, which increased lactic acid concentration and lactic acid to acetic acid ratio, decreased yeast count during aerobic exposure, and improved aerobic stability. These findings offer useful information for optimizing SDA usage in silage, assuring improved quality and longer storage, and thereby improving animal husbandry and sustainable feed practices.

Nisin and Organic Acid Salts Improved the Microbial Quality, Extended the Shelf Life, and Maintained the Sensory Attributes of Semidry Beef Luncheon Marketed at Adverse (35-40 °C) Ambient Summer Temperatures.

Semidry beef luncheon may undergo deteriorative changes during storage at ambient temperatures in tropical and subtropical regions including Egypt. This study was conducted in a meat plant in Egypt with the aim of overcoming the economic losses from the returns of spoiled unsold beef luncheon displayed in grocery stores at adverse summer temperatures of 37 °C or more. Ten approaches were applied using different preservatives, comprising sodium nitrite, nisin, potassium sorbate, and organic acid salts (a combination of sodium lactate, sodium acetate, and sodium diacetate). In addition, the product was cooked at different temperatures and was stored for 21 days at 37 °C, during which time the shelf life, microbial quality, pH, and sensory attributes were investigated. By Day 21 of storage, the luncheon contained 50 mg/kg sodium nitrite, 25 mg/kg nisin, and 1000 mg/kg organic acid salts and, when cooked at a final core temperature of 92 °C, exhibited reductions in aerobic plate count, anaerobic plate count, lactic acid bacterial count, and mold and yeast counts by 4.32, 3.54, 3.47, and 1.89 log10 CFU/g, respectively, when compared with the control. The sensory attributes and pH were also maintained in the final products of such treatment, with no product return and the avoidance of economic loss. This study presents a novel approach for solving the major problem of the deteriorative changes that occur in semidry luncheon sausage and similar meat products which require rejection with a huge economic loss, especially in tropical and semitropical areas of the world that have similar problems of high climatic temperatures and a low availability of energy or technological resources.

Effect of dispersant on the performances of an ice slurry-wet precooling system

This study addresses the problem of prolonged precooling time and excessive weight loss of fruits and vegetables during postharvest processes. Ice slurry precooling system shows potential but faces challenges like low undercooling and ice blockage. Dispersants are introduced to optimize heat and moisture transfer as well as the flow characteristics of the ice slurry. This research investigates the effects of four dispersants on the performance of an ice slurry-based wet precooling system through experiments. Key parameters analyzed include temperature and humidity in the chamber, cooling rate, and weight loss rate of the tested load. Results show that the addition of dispersants effectively reduces the freezing temperature, enhancing the cooling rate in the system. Among the four dispersants tested, sodium diacetate yields the lowest freezing temperature of −6.4 °C and the highest cooling rate of 0.3 °C min−1. Furthermore, dispersants influence moisture transfer between ice slurry and circulating air, impacting the humidity within the precooling chamber. Notably, the addition of sodium diacetate results in the lowest weight loss rate of 2.74 %. This research shows the potential of using dispersants in ice slurry-based wet precooling systems to enhance the postharvest preservation of fruits and vegetables.

Dietary sodium diacetate inclusion relieved hepatic glycogen deposition, oxidative stress, and intestinal microbial imbalance of largemouth bass (Micropterus salmoides) fed high dietary carbohydrate

The present investigation was designed to identify whether sodium diacetate could improve the growth performance, antioxidant capacity, glucose metabolism and intestinal microbiome balance of largemouth bass (Micropterus salmoides) feeding high dietary carbohydrate. Three isonitrogen and isolipid diets comprising 0 g/kg, 1 g/kg, and 2 g/kg of sodium diacetate were manufactured. Each diet was fed to 105 juvenile largemouth bass of 5.8 g for nine weeks. The results demonstrated that dietary sodium diacetate significantly reduced the content of serum glucose and hepatic glycogen (P < 0.05). Meanwhile, dietary sodium diacetate incorporation significantly enhanced the expression of insulin receptor a (ira), insulin receptor b (irb), phosphoinositide-3-kinase regulatory subunit 1 (pi3kr1) and AKT serine/threonine kinase 1 (akt1) (P < 0.05), which were associated to the insulin pathway and partly correlated with the increased expression of genes related to glycolysis, such as glycerol kinase (gk) and phosphofructokinase liver type (pfkl). Moreover, the amount of malondialdehyde (MDA) was dramatically reduced with the addition of dietary sodium diacetate (P < 0.05). Additionally, the antioxidant capability was enhanced with the raise of nuclear factor erythroid derived 2 (nfr2) and the decrease of kelch like ECH associated protein 1 (keap1) being identified as a possible mediator (P < 0.05). The analysis of bacterial 16S rRNA V3–4 region indicated that the intestinal microbiota profile was significantly altered at both phylum and genus level with dietary sodium diacetate inclusion (P < 0.05), with decreased relative abundance of Mycoplasm, which belonged to Firmicutes. In conclusion, the addition of sodium diacetate to the ration improved glucose metabolism, antioxidant capacity and intestinal flora of largemouth bass and the optimal level of addition was 2 g/kg.

Assessment of the safety of the feed additives acetic acid, calcium acetate and sodium diacetate for fish (FEFANA asbl).

Following a request from the European Commission, EFSA was asked to deliver a scientific opinion on the safety of acetic acid, calcium acetate and sodium diacetate as technological feed additives (preservatives) for salmonids/fish. The additives are already authorised for use for all animal species other than fish. In previous opinions, the FEEDAP Panel concluded that a maximum concentration of 2,500 mg acetic acid/kg complete feed (or 1,000 mg/L water for drinking) was safe for poultry, pigs and pet animals. Ruminants were considered to exhibit a higher tolerance. Due to lack of data for salmonids, the Panel could not conclude on the safety of acetic acid and its salts for fish. The applicant has provided supplementary information consisting in a tolerance study in Atlantic salmon (Salmo salar) and a literature search to support the safety of acetic acid in fish. Considering all the available information, the FEEDAP Panel concluded that acetic acid (and its salts by analogy) is considered safe for fish up to the maximum recommended supplementation level of 2,500 mg acetic acid/kg complete feed.

The Effect of Commonly Used Organic Acids on the Microbiota of Cured Deli-Style Turkey Breast

The purpose of this study was to investigate changes in the microbial community structure consisting of spoilage lactic acid bacteria (LAB) when sodium lactate (SL) and SL + sodium diacetate (SD) are included in RTE meat product formulations at concentrations commonly used for controlling Listeria monocytogenes. Sliced cooked, vacuum-packaged turkey breast samples containing no SD or SL (control [C]), 0.125% SD, and the combination of 2.5% SL + 0.125%SD (SLSD) were inoculated with a target of 3 log colony-forming units (CFU)/g of 5 different LAB species (Lactobacillus sakei, Leuconostoc mesenteroides [bacon and deli-shaved ham isolates], Lactococcus lactis, and Enterococcus faecium) and stored at 4°C for 35 d. Microbial community changes were analyzed utilizing 16S ribosomal RNA (rRNA) gene sequencing for the V4 region from the samples collected at days 0, 7, 14, 21, and 35. No significant difference (P&amp;gt;0.05) was observed between the richness of microbial community for all treatments. According to Bray-Curtis dissimilarity matrix and permutational analysis of variance, a significant difference in β-diversity was observed only between C and SLSD (P&amp;lt;0.05) because of the antimicrobial effect of the addition of SL that slowed down changes in microbial community composition until day 14. L. sakei remained a dominant strain throughout 35 d of storage regardless of treatment, whereas L. mesenteroides existed with a very low abundance. Two of the five strains were not seen after day 7. No significant effect (P&amp;gt;0.05) was observed for the SD treatment compared with C in the microbiota. According to the results from this study, only SLSD affected the microbial community structure at the beginning of the storage. This study demonstrated that the incorporation of SL in the formulation slowed down the microbial spoilage and the changes in the microbiota of RTE meat products.

Control of grey mould by sodium diacetate treatments and its effects on postharvest quality of ‘Red Globe’ grapes

This paper studied the effects of sodium diacetate (SDA) treatment on the decay of grapes caused by Botrytis cinerea and on postharvest preservation during storage, The results show that more than 3 g/L of SDA could completely inhibit the growth of B. cinerea in vitro. Grapes treated with 5 g/L SDA significantly improved the activities of antioxidant enzymes and upregulated the expression level of PR gene families. SDA treatments significantly reduced the rotting rate and maintained good quality of grapes in storage. The results are of significance to reveal the induction mechanism of SDA on disease resistance of grapes.

The fabrication of films based on polymer and containing nanoclay, sodium diacetate, and tert‐butyl hydroquinone for packaging rainbow trout

This study investigates the fabrication of films based on a polymer containing nanoclay, sodium diacetate (SDA), and tert-butyl hydroquinone (TBHQ) for packaging rainbow trout fillets. The films were prepared by the addition of 2% SDA (SDA film), 2% TBHQ (TBHQ film), and a combination of both (1% SDA+1% TBHQ) into polyethylene polymer (93.00%) and montmorillonite nanoclay (5.00%). A film lack of nanoclay, SDA, and TBHQ was prepared and considered a control film. A film was also prepared by the addition of 95g polyethylene+5g nanoclay (Nanoclay). Morphological properties of the films were investigated by a scanning electron microscope (SEM). In vitro antioxidant properties and antibacterial activities of the films and their effects as the coating on fish samples were evaluated against Listeria monocytogenes, Salmonella typhimurium, and Escherichia coli. The effects of films on oxidative stability, antibacterial activity, pH, total volatile basic nitrogen (TVBN), and total viable count (TVC) of fish samples were assessed. The SEM results showed the homogenous dispersion of SDA and TBHQ into films. The SDA, TBHQ, and ST films showed antibacterial activity against L. monocytogenes, S. typhimurium, and E. coli compared with the control film as the coating and under in vitro conditions (p<0.05). The TBHQ and ST films exhibited higher antioxidant activity and prevented the oxidation as the coating. The films prepared from the SDA, TBHQ, and ST prevented an increase in TVC and TVBN (p<0.05). The ST films can prevent spoilage in fish samples and can be utilized in the food industry. PRACTICAL APPLICATION: We successfully prepared films with the help of nanoclay, sodium diacetate (SDA), and tert-butyl hydroquinone (TBHQ) on polyethylene for packaging fish fillets. Films containing SDA, TBHQ, and nanoclay showed antibacterial activity and prevented spoilage. The films can be used for packaging fish fillets.

Activity of Binary Combinations of Natural Phenolics and Synthetic Food Preservatives against Food Spoilage Yeasts.

Natural compounds are a suitable alternative to synthetic food preservatives due to their natural origin and health-promoting properties. In the current study, phenolic-phenolic and phenolic-synthetic combinations were tested for their antibiofilm formation, anti-planktonic growth, and anti-adhesion properties against Debaryomyces hansenii, Wickerhamomyces anomalus (formerly Pichia anomala), Schizosaccharomyces pombe, and Saccharomyces cerevisiae. The phenolics were vanillin and cinnamic acid, while the synthetic preservatives were sodium benzoate, potassium sorbate, and sodium diacetate. The vanillin-cinnamic acid combination had synergistic effect in all the tested yeasts for the biofilm inhibition with a fractional inhibitory concentration index (FICI) of ≤0.19 for W. anomalus, 0.25 for S. pombe, 0.31 for S. cerevisiae, and 0.5 for D. hansenii. Most of the phenolic-synthetic combinations had indifferent interaction regarding biofilm formation. The vanillin-cinnamic acid combination also had higher activity against spoilage yeasts adhesion on the abiotic surface and planktonic growth compared to the phenolic-synthetic combinations. For the phenolic-synthetic anti-planktonic activity, synergistic interaction was present in all the vanillin-synthetic combinations in S. pombe, vanillin-sodium benzoate and vanillin-potassium sorbate in S. cerevisiae, vanillin-sodium benzoate in W. anomalus, and cinnamic acid-sodium diacetate in S. pombe. These results suggest a novel antimicrobial strategy that may broaden the antimicrobial spectrum and reduce compound toxicity against food spoilage yeasts.

Influences of Organic Acid Salts and Bacterial Additives on Fermentation Profile, Aerobic Stability, and In Vitro Digestibility of Total Mixed Ration Silage Prepared with Wet Hulless Barley Distillers’ Grains

This study aimed to investigate the impacts of three organic acid salts and two bacterial additives on the fermentation profile, in vitro digestibility and gas production, and aerobic stability of total mixed ration (TMR) silage prepared with 10% fresh weight (FW) of wet hulless barley distillers’ grains (WHDG), 35% FW of common vetch, 15% FW of whole-crop oat, 10% FW of hulless barley straw, and 30% FW of mixed concentrate. The total mixed ration (555 g kg−1 FW) was ensiled with six treatments: (1) no additives (control); (2) calcium propionate (CAP; 0.5% FW); (3) potassium sorbate (POS; 0.1% FW); (4) sodium diacetate (SDA; 0.5% FW); (5) Lactobacillus buchneri (LB; 1 × 106 cfu g−1 FW); and (6) Lactobacillus casei (LAC; 1 × 106 cfu g−1 FW). All silos (20 L) were opened for the fermentation profile and in vitro digestibility analysis after 95 days of fermentation, and then subjected to an aerobic stability experiment for 14 days. All the TMR silage was well preserved with a low pH (4.32~4.51), acceptable levels of butyric acid (1.34~1.56 g kg−1 dry matter), and ammonia nitrogen (69.1~87.1 g kg−1 total nitrogen). All the groups were steady during aerobic exposure, while the SDA treatment was more stable with lower populations of undesirable microorganisms on day 14. The CAP, POS, and SDA treatments evidently (p &lt; 0.05) enhanced the in vitro digestibility of dry matter (54.8~57.5 vs. 48.4%) and neutral detergent fiber (48.4~51.6 vs. 41.1%) compared to the control. By comprehensive consideration, SDA is recommended as additive to enhance fermentation quality, aerobic stability, and in vitro digestibility of TMR silage containing 10% FW of WHDG.

Application of sodium diacetate, potassium lactate and calcium lactate as a microbial decontaminant during processing and storage of the traditional meatballs (rista)

The traditional meat products undergo microbial spoilage and lipid oxidation like other meat products because of their suitability as a medium for microbial growth, which in turn affect safety, quality and shelf life. In the case of traditional meat products like rista, ghostabha, kebab and several other products prepared in Kashmiri wazwan, organic acids or their salts have not been used to date. The present study was therefore aimed to evaluate the effect of different organic acid salts and storage conditions on various quality parameters of traditional meat products. Sodium diacetate (0.25%), potassium lactate (2.5%) and calcium lactate (2.5%) were used in three batches of traditional meat products. Sodium diacetate (SDA) treated samples showed lower total plate count (TPC) under refrigerated storage as compared to ambient storage. The SDA-treated sample retained the lowest value for TBARS (1.9 mg MDA/kg) and free fatty acid (3.2%) on the 15th day of refrigerated storage. Significantly (P ≤ 0.05) higher values for L*, a* and b* were maintained by SDA treated samples as compared to control, potassium lactate (PL) and calcium lactate (CL) treated samples under refrigeration conditions throughout the storage period. Organic acid treatment improved the quality attributes of the meat product during the storage period. The use of organic acids as a preservative in these products will help in reducing the use of synthetic agents. Further increase in the shelf life of traditional meat products by application of organic acids will help in their commercialization, marketing and round the year availability.Graphical

Effects of sodium diacetate and microbial inoculants on fermentation of forage rye

Rye (Secale cereale L.) is a valuable annual forage crop in Korea but there is limited information about the impact of chemical and biological additives on fermentation characteristics of the crop. This experiment was conducted to investigate fermentation dynamics of wilted forage rye treated with the following six additives; control (no additive), sodium diacetate applied at 3 g/kg wilted forage weight (SDA3), 6 g/kg wilted forage weight (SDA6), inoculations (106 CFU/g wilted forage) of Lactobacillus plantarum (LP), L. buchneri (LB), or LP+LB. The ensiled rye sampled at 1, 2, 3, 5, 10, 20, 30, and 45 days indicated that the acidification occurred fast within five days of storage than the rest of the storage period. The microbial inoculants decline the pH of ensiled forage, more rapidly than the control or SDA treated, which accompanied by the decrease of water-soluble carbohydrates and increase of lactic acid. Compared with the control silage, all treatments suppressed ammonia-nitrogen formation below to 35 g/kg DM throughout the sampling period. Suppression of total microbial counting occurred in SDA6, LP, and LP + LB. The lactic acid production rates were generally higher in microbial inoculation treatments. Acetic acid concentration was lowest in the LP-treated silage and highest in the SDA- and LB-treated silages. The in vitro dry matter (DM) digestibility and total digestible nutrients were the highest in the silage treated with SDA (6 g/kg) at day 45 of ensiling. Based on lower ammonia-nitrogen concentrations and higher feed value, ensiling forage rye treated with SDA at 6 g/kg is promising through enhanced silage quality.

Increasing the Quality of Blood Tofu in an Industrial Slaughterhouse of Thailand

Blood tofu, or cooked duck blood curd, is a Chinese delicacy in East Asia. Its quality and shelf-life are low due to microorganism contamination during production. Therefore, the present study was performed to investigate the role of sodium diacetate (SD), sodium chloride (NaCl), and polyethylene glycol 400 (PEG) combinations in increasing the quality of blood tofu. A total of 45 cooked duck blood curd samples were randomly divided into 3 groups with 3 replicates per group. The first two groups were used to investigate the effect of SD, NaCl, and PEG combinations on microbiological and physical analyses for non-inoculated samples. Another group was used to determine the effect of antimicrobial combinations on Lactobacillus plantarum, Pseudomonas fluorescens, Salmonella typhimurium, Escherichia coli, and Staphylococcus aureus in inoculated samples that were inoculated with these bacteria. All groups were treated with control-sterilized water, 0.15% SD (w/v) + 1.25% NaCl (w/v), 0.30% SD (w/v) + 1.25% NaCl (w/v), 0.15% SD (w/v) + 0.15% PEG (w/v), and 0.15% SD (w/v) + 1.25% NaCl (w/v) + 0.15% PEG (w/v). The results indicated that soaking cooked duck blood curd samples in antimicrobial agent combinations could reduce mesophile and psychrophile bacteria counts in non-inoculated samples. Additionally, 0.15% SD + 1.25% NaCl + 0.15% PEG combination had a higher reduction in mesophile and psychrophile counts, compared to soaking the samples in 0.30% SD + 1.25% NaCl, 0.15% SD + 1.25% NaCl and 0.15% SD + 0.15% PEG combinations. Similarly, this combination showed a significant decrease in lactic acid bacteria, Pseudomonas, Salmonella, Escherichia coli, and Staphylococcus aureus counts in inoculated samples. Furthermore, soaking the samples in 0.15% SD + 1.25% NaCl + 0.15% PEG combination did not negatively affect the samples’ physical quality. Soaking the samples in 0.15% SD + 1.25% NaCl + 0.15% PEG combination inhibited the growth of mesophile, psychrophile, and Pseudomonas in non-inoculated samples after storage for 10, 6, 10, and 8 days in a slaughter warehouse at 7℃, respectively, and extended shelf-life of samples for 16 days. Regarding physical quality changes, this treatment delayed the reduction of pH, hue, hardness, and chewiness of the samples after storage for 10, 8, 12, and 10 days, respectively. Thus, SD, NaCl, and PEG combination had a high preservative potential for cooked duck blood curd used in industrial slaughterhouses. Keywords: Blood curd, Duck, Organic acid salt, Polyethylene glycol, Quality changes

Viability of Listeria monocytogenes and Salmonella spp. on Slices of a German-Style Bologna Containing Blends of Organic Acid Salts During Storage at 4 or 12°C

Viability of cells of Listeria monocytogenes or Salmonella spp. was quantified on slices of a German-style bologna manufactured by a local butcher to contain no added antimicrobials or to include 0.9% or 1.3% of a blend of potassium acetate and sodium diacetate (K-Ace) or 2.5% of a blend of potassium lactate and sodium diacetate (K-Lac) as ingredients. After slicing (ca. 7.1 cm L by 6.7 cm W, ca. 0.5 cm thick, ca. 22.4 g each), a single slice of bologna was placed into a nylon–polyethylene bag and surface inoculated with 250 µL per side of a five-strain mixture of either cells of L. monocytogenes or Salmonella spp. to achieve an initial level of ca. 3.5–4.0 log CFU/slice. The packages were vacuum-sealed and then stored at 4 or 12°C for 90 and 30 days, respectively. Without antimicrobials added to the formulation, L. monocytogenes numbers increased by ca. 5.4 and 6.0 log CFU/slice at both 4 and 12°C during the entire 90- and 30-day storage period, respectively. Likewise, levels of Salmonella also increased by ca. 6.0 log CFU/slice at 12°C in the absence of added antimicrobials; however, levels of this pathogen decreased by ca. 1.7 log CFU/slice after 90 days at 4°C. With the inclusion of 0.9% or 1.3% K-Ace or 2.5% K-Lac in the bologna formulation, levels of L. monocytogenes decreased by ca. ≤0.7 log CFU/slice after 90 days at 4°C, whereas levels of Salmonella decreased by ca. 1.6–2.3 log CFU/slice. After 30 days at 12°C, levels of L. monocytogenes increased by ca. ≤3.4 log CFU/slice on product containing 0.9% K-Ace or 2.5% K-Lac but remained relatively unchanged on slices formulated with 1.3% K-Ace. For Salmonella, in the presence of 0.9% or 1.3% K-Ace or 2.5% K-Lac, pathogen levels decreased by ca. ≤0.7 log CFU/slice at 12°C after 30 days. Our data validate that the inclusion of K-Ace (0.9% or 1.3%) or K-Lac (2.5%) as ingredients is effective for controlling L. monocytogenes and Salmonella on slices of bologna during refrigerated storage.

Assessment of organic acid salts on fermentation quality, aerobic stability, and in vitro rumen digestibility of total mixed ration silage.

The work aimed to investigate the effects of four organic acid salts on fermentation quality, aerobic stability, and in vitro rumen digestibility of total mixed ration (TMR) silage prepared with citric acid residue, wet brewers' grains, and Napier grass. The TMR was ensiled with the following: (1) no additives (control), (2) 0.1% sodium benzoate (SB), (3) 0.1% potassium sorbate (PS), (4) 0.5% sodium diacetate (SDA), (5) 0.5% calcium propionate (CAP) on a fresh weight basis. All silos (10 L) were opened after 60days of ensiling to determine fermentation profiles and in vitro rumen digestibility, and then were subjected to a 9-day aerobic stability test. Four organic acid salts significantly (p < 0.05) increased dry matter contents, lactic acid bacteria count, and decreased ethanol content and yeast count compared with the control. The SDA and CAP significantly (p < 0.05) increased water-soluble carbohydrates, lactic acid, and crude protein contents, and decreased pH, ammonia nitrogen, neutral detergent fiber, and hemicellulose contents compared with other TMR silages after 60days of ensiling. Organic acid salts significantly (p < 0.05) prolonged the hours of aerobic stability and significantly (p < 0.05) increased cumulative gas production and potential gas production compared with the control. The treatments of SDA and CAP significantly (p < 0.05) improved aerobic stability as indicated by higher (p < 0.05) lactic acid and water-soluble carbohydrates contents, and lower (p < 0.05) pH, ammonia nitrogen, ethanol contents, and yeast count compared with the control. The treatments of SDA and CAP significantly (p < 0.05) increased in vitro rumen parameters, as indicated by higher (p < 0.05) in vitro digestibility of dry matter, crude protein, and neutral detergent fiber after 60days of ensiling. Overall, these results indicated that the addition of SDA and CAP could ensure the good fermentation quality and improve aerobic stability of TMR silages. By comprehensive consideration, CAP was recommended for improving fermentation quality, aerobic stability, and in vitro rumen digestibility of TMR silages prepared with wet brewers' grains, citric acid residue, and Napier grass.

Nematicidal Activity of Organic Food Additives

Organic food additives are popular in various spheres of human activity: the food industry, agriculture, veterinary and human medicine, the chemical industry, and other sectors. Due to the relatively short time of their breakdown in the environment, their non-toxicity to various organisms in certain concentrations, and their large annual amounts of production, application, and influx into the environment, it is an important task to study their influence on ecology. To help reduce toxic pressure on the environment, we studied the influence of 32 organic food additives on larvae of the nematodes Strongyloides papillosus, Haemonchus contortus, Muellerius capillaris, which are parasites of the digestive tracts of ruminants. This article presents the results of in vitro studies of organic food additives (acetic, propionic, lactic, sorbic, adipic, fumaric, malic, citric, ascorbic, and dehydroacetic acids, sodium formate, calcium formate, potassium acetate, calcium acetate, sodium diacetate, calcium propanoate, sodium lactate, potassium sorbate, sodium sorbate, calcium sorbate, trisodium citrate, monosodium glutamate, sodium dehydroacetate, sodium benzoate, potassium benzoate, calcium benzoate, biphenyl, dibutylhydroxytoluene, hexamethylenetetramine, 2-phenylphenol, natamycin, and nisin) on nematode larvae at various stages of their development. Propionic acid and 2-phenylphenol, used in the food industry, exerted notable nematicidal effects on larvae of S. papillosus, M. capillaris, and H. contortus: 1% concentrations of the substances killed 85% of these larvae, except H. contortus, which were tolerant to 2-phenylphenol in 52% of cases. Other tested food additives at 1% concentrations could not kill more than 70% of invasive nematode larvae in 24 h. The research determined various degrees of toxicity of the studied substances to invasive (third age) and non-invasive (first and second age) larvae, which are related to a decrease in the feeding intensity of parasitic nematodes on the stage of third age larvae. Thus, some organic food additives, introduced into the environment with food wastes, are able to affect the vitality of certain nematode species to a varying extent.

Effects of sodium diacetate or microbial inoculants on aerobic stability of wilted rye silage.

The primary goal was to identify the effectiveness of chemical or biological additives in delaying the deterioration of early-harvested wilted rye silage after exposure to air. Rye harvested as a whole plant at the early heading stage was wilted for 24 h. The wilted forage was divided into treatments including sodium diacetate (SDA) at 3 (SDA3) and 6 g/kg (SDA6), Lactobacillus plantarum (LP), L. buchneri (LB), or their equal mixture (LP+LB) at 1×106 colony-forming unit/g fresh matter. After 60 d of conservation in 20-L silos, lactic acid was greater in LP and LP+LB silages than other treatments (102 vs 90.2 g/kg dry matter [DM]). Acetic acid was greatest in SDA6 (32.0 g/kg DM) followed by LB (26.1 g/kg DM) and was lowest in LP treatment (4.73 g/kg DM). Silage pH was lower with microbial inoculation and the lowest and highest values were observed in LP and untreated silages, respectively. After 60 d, neutral detergent fiber concentration was lowest in SDA6 silages, resulting in the greatest in vitro DM digestibility (846 g/kg DM). Aerobic stability was longest in SDA6 (176 h) followed by LB treatment (134 h). Instability after aerobiosis was greatest in LP silages (68 h), about 8 h less than untreated silages. After aerobic exposure, yeast and mold numbers were lowest in SDA6 silages, resulting in DM loss minimization. Exhaustion of acetic acid and lactic acid after aerobic exposure was lowest with SDA6 but greatest with untreated and LP silages. Treatment of early-cut wilted rye forage with SDA at 6 g/kg resulted in silages with higher feeding value and fermentation quality, and substantially delayed deterioration after aerobic exposure, potentially qualifying SDA at this load for promotion of silage quality and delaying aerobic spoilage of early-harvested (low DM) rye forage.