Cold Storage Stability Research Articles

Effect of chitosan and its derivatives on food processing properties of potato starch gel: Based on molecular interactions

Potato starch gel foods are appreciated for their distinctive taste; however, they face challenges such as high paste viscosity, susceptibility to aging, and poor cold-storage stability, limiting their industrial production. This study aimed to enhance potato starch characteristics by investigating the effects of alum, chitosan, carboxymethyl chitosan, and quaternized chitosan on its pasting, rheological, and textural properties. Results revealed that the addition of 1% chitosan, carboxymethyl chitosan, and quaternized chitosan significantly reduced the gelatinization viscosity of potato starch. Moreover, the addition of alum or chitosan provided better shear resistance and reduced shear-thinning behavior. The potato starch gel prepared with chitosan was harder than that prepared with alum. These findings highlight the influential roles of alum, chitosan, and their derivatives in potato starch and provide a theoretical foundation for their application in potato starch gel foods.

Impact of frozen storage on quality and cold storage stability of smoked deep-skinned fillets from well-fed Atlantic mackerel

To ensure year-round availability and stability of Atlantic mackerel caught in Icelandic waters during summer after intensive feeding, freezing is essential. Due to the high lipid content and sensitive lipid composition of the fish caught at this time, the fish industry requires detailed research to understand the mechanisms underlying the degradation processes occurring during storage and processing, in order to develop high-value hot-smoked products. Therefore, the impact of frozen storage at − 25 ± 1.8 °C (for 6, 9, and 20 months) prior to hot-smoking, was investigated on the physicochemical, microbial, and sensory quality of deep-skinned, smoked fillets from well-fed Atlantic mackerel caught in late August. The stability of hot-smoked fillets stored at 1 ± 0.6 °C was then monitored for 28 days. Total aerobic viable counts (TVC) remained below acceptable thresholds due to the combined effects of brining, freezing, and hot-smoking, while Listeria monocytogenes was not detected in the hot-smoked products. Slow formation of oxidation products was observed during the chilled storage, especially in the fish frozen for 9 months. Minor lipid deterioration was also detected during sensory analysis, but all spoilage indices remained within acceptable thresholds for shelf-life. Frozen storage for up to 20 months thus effectively maintained the sensory acceptability and suitability of deep-skinned mackerel fillets, making them an excellent choice for the fish-smoking industry.

Development, characterization and use of rosemary essential oil loaded water-chestnut starch based nanoemulsion coatings for enhancing post-harvest quality of apples var. Golden delicious

The study aimed at evaluating the influence of water-chestnut starch-based coatings loaded with rosemary essential oil (REO) at concentrations of 0.10%, 0.25% and 0.50% (w/v) on postharvest cold storage stability of apple var. Golden delicious for 120 days. Average droplet diameter of nanoemulsions was in range of 315–450 nm and it increased with increase in the REO concentration. Minimum weight loss was observed in fruits treated with coating material containing 0.50% REO. Samples coated with starch+0.50% REO exhibited highest firmness value of 68.22 ± 1.02 N under controlled atmosphere storage (CAS). Anthocyanins, ascorbic acid, total phenolic content and antioxidant activity were retained in all samples coated with formulated emulsion. Antifungal assay against Pencillium expansum indicated that 0.50% REO had maximum antifungal activity. Increase in REO concentration from 0.10 to 0.50% in starch coating formulations resulted in reduced lesion diameter in coated samples under both the storage conditions. Lesion diameter (LD) was found highest in control (39.40 ± 0.20 mm) under ambient conditions. Coated fruit samples showed a significant (p≤0.05) reduction in LD under both the ambient and CAS conditions however, more pronounced effect was reported under CAS. Fruits coated with edible coatings enriched with different REO concentrations under CAS exhibited significantly (p≤0.05) lower chilling injury index (ST+0.50%REO < ST+0.25%REO<0.10%REO) compared to control.

Combined effects of prior plasma-activated water soaking and whey protein isolate-ginger extract coating on the cold storage stability of Asian sea bass (Lates calcarifer) steak

The combination of prior plasma-activated water soaking (PS) before whey protein isolate-crude ginger extract coating (WC) on the cold storage stability (4 °C) of Asian sea bass steaks (ASBS) was first investigated in the present study. The total viable count of control, WC, PS, and PS + WC exceeded the acceptable limit on Days 8, 15, 25, and 30 of storage, respectively. Throughout storage, all three treated samples had a total psychotropic count (TPC) and a Pseudomonas spp. count below the permitted level, with the TPC of control exceeding the limit on Day 20. The PS + WC reduced off-flavour development measured by total volatile base-nitrogen, trimethylamine, and propanal, as well as lipid, protein, and myoglobin oxidations (p < 0.05) compared to PS or control. The PS + WC reduced the discolouration, drip loss, and textural softening of ASBS (p < 0.05), which was comparable to PS and WC (p > 0.05). Thus, conjunction of PS and WC was an effective hurdle technique for extending the shelf-life of ready-to-cook ASBS. This approach was practical and industrially applicable. • PAW soaking plus WPI-ginger extract coating improved shelf-life of sea bass steaks. • With this hurdle, microbial indices were within the acceptable level up to 30 days. • Off-flavour development was reduced and oxidative stability was improved. • Shelf-life of chilled sea bass steaks was extended up to 30 days.

벼 품종의 쌀 묵 가공 적합성

Purpose: This study evaluated the suitability of rice varieties for the preparation of 100% rice mook, a starch-based Korean food with a jelly-like consistency, typically made of buckwheat or acorns. Methods: Six varieties of dry-milled rice flours, Saemimyeon, Dodamssal, Saegoami, Milyang333, Saeilmi, and Shingil, were gelatinized using a rapid visco analyzer (RVA) canister and stored at either 4℃ or frozen for 24 hr and one week. Results: Dodamssal, Saegoami, Milyang333, and Saemimyeon behaved like hard gels and hence could be used to prepare mook. Milyang333 and Saemimyeon, the rice varieties with the lowest water absorption, exhibited significantly (p < 0.05) higher peak and setback viscosity than the other varieties. Additionally, they exhibited the best cold storage stability, highest springiness, and lowest adhesiveness in the texture profile analysis (TPA) among all the varieties studied. Dodamssal, the variety with the highest amylose content and a weak gelatinization viscosity pattern, exhibited fracturability and low springiness. In the sensory test, similar to the TPA test, Dodamssal exhibited high hardness, high brittleness, and a lack of elasticity, whereas Milyang333 and Saemimyeon exhibited high elasticity without brittleness. Conclusion: Amylose content, which is used as the primary index for determining processing suitability does not provide sufficient information to predict suitability for mook processing. The results show that rice varieties with a high amylose content, low water absorption, and high gelatinization viscosity can be used to produce mook, and Milyang333 and Saemimyeon appear to fulfill these criteria.

Effects of Auricularia auricula-judae polysaccharide on pasting, gelatinization, rheology, structural properties and in vitro digestibility of kidney bean starch

Auricularia auricula-judae polysaccharide (AP) has unique molecular structures and multiple bioactivities with excellent gel-forming property and thermal tolerance. However, few researches focus on the interactions between AP and legume starches. In this study, the effects of AP on the pasting, gelatinization, rheology, microstructure, and in vitro digestibility of kidney bean starch (KBST) were evaluated. The pasting, gelling and structural properties of AP-KBST mixtures were characterized by rapid visco analyzer, rheometry, texture analyzer, laser particle analyzer, low-field nuclear magnetic resonance, Fourier transform infrared spectroscopy and scanning electron microscopy, respectively. And an in vitro method was employed to measure the digestibility of AP-KBST composites. The pasting viscosity, swelling degree of starch granules, viscoelasticity, gel strength, cold storage stability and water-retention capacity of KBST were enhanced with increasing AP concentration. The combination of AP and KBST exhibited a higher short-range ordered and a firmer and denser structure than that of KBST alone. Moreover, AP increased the contents of resistant starch and slowly digestible starch, which were positively correlated with the storage modulus and the degree of order, thereby suggesting that the formation of strong and ordered gel network structure by synergistic interactions between AP and KBST was responsible for the reduced starch digestibility.

A new approach in improving granular cold water swelling starch properties using xanthan gum and β-lactoglobulin/xanthan gum electrostatic coupled gel

Granular cold water swelling (GCWS) starches are capable of creating cold-set gels without any heat treatment. However, similar to their thermally gelatinized counterparts, there are some techno-functional challenges related to these physically modified starches. The main objective of this study was to investigate the probable improvement of physical and mucoadhesive properties of alcoholic-alkaline modified GCWS tapioca and corn starches (GCWSTS and GCWSCS, respectively) in the presence of xanthan gum (XG) or β-lactoglobulin-XG electrostatic coupled gel (βlg-XG ECG). Results showed that the viscosity, consistency, pseudo-plasticity, structure recovery, and cold storage stability were improved, and the turbidity development and susceptibility against temperature rise and successive freeze-thaw cycles decreased by increasing the XG to starch ratio from 1:99 to 10:90 in the XG/GCWSTS mixtures, and from 5:95 to 10:90 in XG/GCWSCS mixtures, compared to the respective GCWS starches. The XG to starch ratios of 1:99 and 2.5:97.5 negatively influenced the characteristics of GCWSCS, except for its mucoadhesion. The maximum work of adhesion was obtained at XG to TS ratio of 5:95. Partial substitution of the starch with βlg-XG ECG increased shear-thinning behavior, percent recovery, and work of adhesion, although to a lower degree compared with XG. In contrast, the ECG could substantially reduce the long-term retrogradation and after-five-cycles freeze-thaw syneresis of the GCWS starches much more than XG, despite having a lower concentration. The results of this study suggested that the XG and βlg-XG ECG are capable of extending the applications of GCWS starches in the heat-sensitive functional formulations and 3D printable foods.

Impact of sage seed gum and whey protein concentrate on the functional properties and retrogradation behavior of native wheat starch gel

Herein, some physicochemical, rheological, and textural properties, as well as retrogradation kinetics of native wheat starch (NWS) gel in the presence of sage seed gum (SSG) and whey protein concentrate (WPC) were investigated. The substitution of NWS with SSG increased the swelling power of starch granules, viscosity, and pseudoplasticity of NWS gel, while the NWS replacement with WPC decreased the swelling power and viscosity of NWS gel. SSG had an outstanding effect on reducing the syneresis of NWS gel during storage at 4 °C and −18 °C, indicating the improvement of cold storage stability of starch gel. From the back-extrusion test, it was found that substitution of NWS with SSG enhanced hardness, cohesiveness, adhesive force, and adhesiveness of starch gel, while these textural attributes were weakened by substitution of NWS with WPC. The SSG effect on retrogradation behavior of NWS gel was concentration-dependent and it retarded the retrogradation of NWS gel at the 5% substitution level. The NWS substitution with WPC reduced the retrogradation kinetics rate, which was more pronounced at the 10% substitution level. However, it was proved that the interactions of SSG and WPC led to a noticeable decrease of retrogradation kinetics rate, indicating the significant retarding effect of these blends on the NWS retrogradation rate. These results show that although WPC weakened the starch network, it had a positive effect on restricting the retrogradation process of NWS gel. As a result, a suitable mixture of NWS-WPC-SSG could effectively improve the functional properties of the starch gel.

Glass transition temperature, rheological, and gelatinization properties of high amylose corn starch and waxy cassava starch blends

In the present study, the physicochemical properties of high amylose corn starch (HACS) with waxy cassava starch (WCS) blends were investigated at different ratios. Glass transition temperature, pasting properties, rheological properties, and textural properties of the starch blends were studied by various techniques. The interactions of the starch blends were studied by plotting and comparing the correlation between the proportions of starch and physicochemical properties. The obtained results indicated that the glass transition temperature, pasting properties, rheological properties showed non-additive effects. In addition, the textural properties of starch blends were significantly improved, which was in a positive relationship with HACS contents. The mixture of HACS and WCS could lead to unexpected physicochemical properties of starch blends, which is beneficial for creating novel texture food products. Practical applications Blending of different starches is a clean-label alternative to modify the properties starches, and the interaction between different starches could lead to unexpected physicochemical properties of starch blends. High amylose corn starch is an important resistant starch with lots of beneficial health effects such as lowering blood lipid levels, increasing laxation, and preventing gall stone formation. Waxy cassava starch is less susceptible to retrogradation and has greater cold-storage stability. The blending of high amylose corn starch and waxy cassava starch has great potential for developing starch-based products with particular functionalities.

Comparative stability of ficin and papain in acidic conditions and the presence of ethanol

Proteolytic enzymes are used for proteolysis and peptide synthesis which can be run in various conditions including low pH value and the presence of ethanol. The most common cysteine protease applied in acidic-alcoholic conditions is well-characterized papain. Ficin, which is closely related to papain in terms of proteolytic activity and substrate specificity, could potentially be applied in the alcoholic beverage industry and peptide synthesis. The aim of this study was to compare papain and ficin stability in process conditions. Comparative stability study showed that ficin as a mixture of different isoforms has a broader range of stability in respect of pH and cold storage stability, in comparison to papain. It retains about 70% of initial activity after 3-week cold storage at low pH and in the presence of ethanol. Unlike ficin, papain loses about 70% of initial activity in the same incubation period as it is more prone to non-native aggregation that was confirmed by FTIR analysis. The presence of multiple isoforms of ficin stabilizes the protease against cold denaturation and aggregation, making it more suitable for biotechnological and laboratory usage than single papain isoform. It is more cold-stable in alcoholic-acidic and acidic conditions suggesting possible replacement of papain with even lower enzyme concentration.

Utilization of chemically modified pearl millet starches in preparation of custards with improved cold storage stability

Custards were prepared using five ingredients: milk powder, modified pearl millet starch, sugar, vanilla essence and water. The effect of adding hydroxypropylated starch (HPS), succinylated starch (SUS), oxidised starch (OXS) and acetylated starch (ACS) on cold storage stability, pasting, textural and sensory properties was studied and compared to custards containing native pearl millet starch (NS). Interestingly, all chemically modified starches reduced syneresis and no water weeping was observed in custard sample incorporating hydroxypropylated starch (HPC) even after 7days of cold storage. Viscoamylographic analysis revealed that custard containing succinylated starch (SUC) had the highest peak viscosity (108.8 BU), whereas HPC showed the least set back viscosity (19.0 BU). Sensory results suggested that assessors preferred HPC over other custards. Custards are preferred for their chewy semi-solid texture. Incorporation of hydroxypropylated starch (HPS) increased hardness, gumminess and chewiness which subsequently led to higher sensory scores during subjective analysis. Also, no retrogradation peak was observed for HPS and acetylated starch (ACS) when rescanned after 14 days. Thus, it could be concluded that HPS could be used in custards to confer low temperature stability by reducing syneresis.

Effect of succinylation on functional and morphological properties of starches from broken kernels of Pakistani Basmati and Irri rice cultivars

Starch extracted from broken kernels of Basmati and Irri rice varieties of Pakistani rice were subjected to modification by addition of succinic anhydride at levels of 2%, 4% and 5% based on dried weight of starch. The succinyl content of Irri rice starch increased with the concentration of succinic anhydride. Scanning electron micrographs revealed presence of dents and fusion of rice starch granules. Swelling power and water retention capacity (WRC) significantly improved after succinylation while on refrigerated storage percent decline in paste clarity of modified rice starches was stable as compared to native Basmati (BC) and Irri (IC) rice starches. Succinylation also reduced solubility, pasting temperature (PT) and gel hardness of starch gels. Improvement was observed in cold storage stability of rice starch succinates as evident from textural profile analysis.

Post succinylation effects on morphological, functional and textural characteristics of acid-thinned pearl millet starches

The effect of succinylation on acid-thinned pearl millet starches hydrolyzed to different levels using 0.1 M and 1 M HCl solutions were studied in terms of morphological, physicochemical, pasting, and textural characteristics. Scanning electron micrographs showed erosion and indentations on surface of dual modified succinylated acid-thinned starches. The results revealed that succinylation of native and acid-thinned starches increased the swelling power and paste clarity significantly. The re-association tendency was greatly reduced in dual modified starches as no retrogradation peak was observed during thermal analysis even after 14 days of refrigerated storage at 4 °C. Also, succinylated acid-thinned starches demonstrated better cold-storage stability with respect to various textural attributes like hardness, chewiness, springiness and cohesiveness when compared to acid-thinned and native starches. Succinylated starch showed 22.6% retrogradation as opposed to 49.1% for unmodified starch. In a nutshell, succinylation is a promising method to overcome high susceptibility of retrogradation in acid-thinned starches.

24. Investigating hydroxyl radicals (OH) and 8-hydroxy-2′-deoxyguanosine as generic biomarkers of cryoinjury and cold storage stability

24. Investigating hydroxyl radicals (OH) and 8-hydroxy-2′-deoxyguanosine as generic biomarkers of cryoinjury and cold storage stability

탈모방법과 성별이 돈육질 및 냉장저장성에 미치는 영향

본 연구는 도축과정 중 탕침법과 박피법의 탈모기법이 돈육질에 미치는 영향을 분석하고 이를 통해 생산된 식육의 냉장 저장성에 미치는 효과를 규명하고자 실시하였다. 탈모기법에 따른 온도체중과 등지방은 탕박을 실시한 처리구가 박피 처리구보다 높은 수치를 나타내었으며 등심 근의 온도에서도 등지방이 두껍고 도체중이 무거웠던 탕박 거세돈이 가장 높은 수치를 나타내었다. pH와 육색에서는 처리구 간 유의적인 차이를 보이지 않았지만 보수력의 경우는 탕박과 박피 처리에 따른 차이가 뚜렷하게 나타났으며 탕박법에 의해 탈모된 처리구에서 보수력이 저하되는 것으로 분석되었다. 냉장 저장 중 지방산패에 의한 TBA 측정의 변화를 분석한 결과 저장 1일 탕박 거세 돈의 경우가 가장 높게 나타났으나 다른 처리구와 더불어 대부분 신선한 상태를 유지하였다. Metmyoglobin의 경우 저장일 별 처리구 간 유의적인 차이를 보이지 않았으나 TBA측정치의 변화와 유사한 경향을 보였다. 총균수의 경우도 처리구 간 유의적 차이를 보이진 않았으며 저장 7일과 14일 사이에 급속하게 미생물이 증식하는 것으로 관찰되었고 14일 이후에는 완전 부패하였다. The aims of this work were to compare the effects of dehairing methods and sex on pork quality and cold storage stability. For this study, one half of40 pigs were dehaired by scalding in the same abattoir, and the other half by dehiding. Each treatment consisted of one half gilts and one half castrated male pigs. Meat quality traits were measured at 24 hr after slaughter, and thiobarbituric acid (TBA), metmyoglobin contents and total plate counts (TPC) were evaluated at 1, 7, 14 and 21 days of cold storage. The carcass weight and backfat thickness of pigs dehaired by scalding were significantly higher than those dehided (p<0.05). Compared to scalded carcasses, dehided carcasses had a lower longissimus dorsi muscle temperature (p<0.05). Furthermore, dehided carcasses had significantly lower drip loss than scalded carcasses (p<0.05). However, meat color parameters were not affected by the dehairing method. During cold storage, TBA values of scalded carcasses were slightly higher initially, whereas the dehided carcasses had higher TBA values at 21 days (p<0.05). The total plate counts (TPC) associated with scalding and dehiding treatment were not significantly different at any point during cold storage. The TPC exponentially increased in both scalded and dehided carcasses from 7 to 14 days of cold storage.

Studies on the Breeding for Improving Starch Properties in Sweet Potato

To develop new uses for sweet potato starch, we studied about breeding for improving starch properties in sweet potato. The amylose content of the germplasm collections of sweet potato ranged from 11.2 to 15.3%. There were varietal and geographical differences in the amylose content of sweet potato. Analysis of the varietal and annual variations in starch properties suggested that selection for pasting temperature, setback and amylose content can be effective. The variations of amylose content in sweet potato and its related diploid wild species could be increased by crossing and mutagenesis, and variants with a low/high amylose content could be selected. Furthermore, a new sweet potato cultivar was developed, featuring low gelatinization temperatures and altered starch fine structure. Gelatinization temperatures and pasting temperatures of Quick Sweet starch were approximately 20°C lower than those of ordinary sweet potato cultivars. The chain-length distribution of amylopectin showed that Quick Sweet starch had a higher proportion of short chains (DP6-11) than the ordinary cultivars. Starch retrogradation, evaluated by leaked water percentage and hardness of starch gels after cold storage, indicated that Quick Sweet starch had excellent cold storage stability.

Starch Properties of New Sweet Potato Lines Having Low Pasting Temperature

AbstractSome new sweet potato lines were developed from progenies of a new cultivar, Quick Sweet, having a low pasting temperature. Starch granules from these lines demonstrated an abnormal morphology characterized by cracking into fragments. Starch and amylose contents were different among these lines. Pasting temperatures of these lines determined by the Rapid Visco Analyser were 53.8 to 66.6°C, i.e. 10 to 20°C lower than that of the control. Peak viscosities of some lines were similar to that of the control. Starch retrogradation, evaluated by percentage of leaked water and hardness of starch gels after cold storage, revealed that the control starch retrograded during storage for two to six weeks, but the starches of some lines retrograded much more slowly than the control starch and exhibited excellent cold storage stability. The pasting temperature had significant positive correlations with the percentage of leaked water and the hardness. These results indicate that Quick Sweet is a useful breeding material for improving pasting and retrogradation properties in sweet potato starch.

Determination of Minerals in Apples by ICP–AES

A laboratory experiment is described that involves the elemental analysis of apples by inductively coupled plasma–atomic emission spectroscopy (IICP–AES). The results of the experiment allow students to predict the cold-storage stability of apples. During the experiment the sample-preparation techniques and digestion procedures involved in elemental analysis of solid organic samples are introduced and the optimization of the ICP–AES is explored. The method detailed can easily be adapted for the analysis of a wider range of elements. The laboratory experiment may also be undertaken using atomic absorption spectroscopy (AAS) with only minor modifications in the sample-preparation procedure.

Effects of sugars and sugar alcohols on thermal transition and cold stability of corn starch gel

Various sugars and sugar alcohols (ribose, xylose, glucose, fructose, mannose, sucrose, maltose, isomaltose, trehalose, xylitol, mannitol, and sorbitol) were compared in their effects on thermal transitions and cold-storage stability of a corn starch–sugar gel (40% starch, starch:sugar=10:1 or 10:3 dry solids basis) using a differential scanning calorimetry. As the molar concentration of sugar increased, the onset temperature and enthalpy for starch melting were increased. Among the sugars, the samples with disaccharides exhibited higher onset temperature and enthalpy than those with monosaccharides at the same molar concentration. Under cold storage (4 or −20 °C), the sugars facilitated amylopectin recrystallization. Fructose and isomaltose produced higher degrees of amylopectin recrystallization than did other sugars. Sugar alcohols produced slightly greater recrystallization than did the corresponding sugars. Ice melting temperature and glass transition temperature ( T′ g) of the freeze-concentrated phase were decreased as the molar concentration of sugars increased, and there was no or little dependence on the chemical structure of sugars. Ice melting enthalpy for the gels showed no clear dependence on sugar concentration or structure. Sucrose addition lowered the ice melting enthalpy (ice formation by rapid freezing), whereas isomaltose or trehalose addition raised it. By cold storage, the T′ g of the starch gels was increased, whereas the ice melting enthalpy was decreased, as a result of water consumption for starch recrystallization. In the gel system (40% starch), sugar addition (10 or 30% based on starch) enhanced starch recrystallization, but decreased the ice melting and glass transition temperatures.

The effect of lactose derivatives lactulose, lactitol and lactobionic acid on the functional and technological properties of potentially probiotic Lactobacillus strains

Lactulose, lactitol and lactobionic acid are unabsorbable lactose derivatives with prebiotic potential. They are utilised in varying extent by different Lactobacillus and Bifidobacterium species/strains. To explore the possibility of improving the properties of probiotic strains with a specific prebiotic, the effect of the lactose derivatives on the technological and functional properties of putative probiotic Lactobacillus strains was studied in vitro. The properties studied were growth in different conditions (aerobic versus anaerobic with varying substrate concentrations), acid and bile tolerance, antimicrobial activity, and stability during cold storage. In general lactose derivatives did not effect the technological or functional properties of the Lactobacillus strains. However, our results suggest that lactulose might improve the bile tolerance and cold-storage stability of Lactobacillus salivarius. Finding synbiotic pairs where the prebiotic would benefit the specific probiotic strain is not a simple task, but worth pursuing for, since this kind of capacity would give added value to the synbiotic product.