Calcium lactate effect on the shelf life of osmotically dehydrated guavas

The effect of calcium lactate on osmodehydrated guavas in sucrose and maltose solutions was monitored during storage under passive modified atmosphere for 24 d at 5 °C. Sample texture and color characteristics, microbial spoilage, sensory acceptance, structural changes, and gas composition inside the packages were periodically evaluated. Calcium lactate inhibited microbial growth on guavas, with yeast and mold counts in the order of 10(2) CFU/g throughout storage. The calcium salt reduced respiration rate of guava products, showing O(2) and CO(2) concentrations around 18% and 3% inside the packages. A firming effect on fruit texture, with up to 5 and 2 times higher stress and strain at failure values and tissue structure preservation could also be attributed to calcium lactate use. However, fruits treated with calcium lactate, osmodehydrated in maltose and sucrose solutions, showed sensory acceptance scores below the acceptability limit (4.5) after 13 and 17 d of storage, respectively.     

Nondestructive tests for measuring the firmness of guava fruit stored and treated with methyl jasmonate and calcium chloride

Ripening is one of the most important processes to occur in fruits and involves changes in colour, flavour and texture. An important goal in quality control of fruits is to substitute traditional sensory testing methods with reliable and quantitative methods. In this study, methyl jasmonate (MJ) (220 μL L^?1) and calcium chloride (at 1%) were applied to guava fruits stored at 6 °C. The compression test (CT) and acoustic impact test were used to monitor the shelf life of guavas. The results obtained using both techniques showed that Young’s modulus diminishes as a function of time in all samples; however, the texture of samples treated for 20 days with MJ deteriorated unacceptably, a condition which did not occur in the samples treated with calcium chloride. The control samples had a shelf life of 20 days. In conclusion, it appears that the acoustic impact test is more appropriate than the CT and has the additional advantage of being a nondestructive technique.     

Microscopic features, mechanical and thermal properties of osmotically dehydrated guavas

The effects of an osmotic dehydration process using sucrose and maltose solutions at 40 and 60 °Brix on microscopic features and some mechanical and thermal properties of guava tissue were studied. Also the addition of calcium lactate to the sugar solutions, aiming at preserving the structure of the processed fruits, was investigated. The guava texture (stress at failure) and the structure as observed by light microscopy were both evaluated, and differential scanning calorimetry (DSC) was used to verify the interaction between calcium ions and cell wall pectin in the guava tissue. The calcium content of the differently treated samples was also related to microscopic features, mechanical and thermal properties of guavas. The osmotic process using sucrose and maltose solutions caused severe structural damage to the guava tissue, and this effect was intensified at higher sugar concentrations and by the use of sucrose solutions. The addition of calcium lactate promoted maintenance of the guava structure, showing turgid cells with well-defined cellular contours, resulting in an increase in hardness and indicating bonding between the Ca²⁺ and cell wall pectin, which was confirmed by the DSC experiments.     

Influence of the type of calcium salt on the cation absorption and firmness of black ripe olives

The preservation of olives intended for processing as black ripe olives must be done in a salt-free environment although it involves the use of calcium addition to retard olive softening. Calcium chloride and calcium lactate were added by up to 1600 mg Ca L⁻¹ (i) in the preservation liquid of olives before darkening and (ii) in the cover packing brine. The highest texture and calcium absorption were found in the latter case. In addition, the sensory characteristics of the final product were not affected by the use of any of the calcium salts studied at concentrations of up to 1600 mg Ca L⁻¹. Calcium chloride and calcium lactate can be employed to obtain higher texture and calcium content in black ripe olives, although it is advisable to add the cation to the cover packing brine of pitted olives rather than to the preservation liquid.     

Effects of calcium chloride and calcium lactate applications with osmotic pretreatment on physicochemical aspects and consumer acceptances of dried papaya

This study explored the effects of calcium chloride (CaCl₂) and calcium lactate (Ca‐L) pretreatments prior to osmotic dehydration on physicochemical characteristics and consumer acceptance of dried papaya. Three different calcium concentrations [0.5, 1.5 and 2.5% (w/v)] were applied to samples before they were soaked in a 30 °Brix sucrose solution and subsequently dried at 70 °C. The results showed that the dried samples treated with calcium exhibited significantly lower moisture content, water activity, apparent density and shrinkage, while volume was higher when compared to the control. Calcium applications did not obviously influence sugar content of samples and maintained the quality of dried papaya in terms of colour and textural characteristics. Calcium chloride at 2.5% (w/v) was found to particularly impart undesirable bitterness to the dried papaya. In contrast, using 2.5% (w/v) Ca‐L provided the best acceptance scores. Thus, the use of Ca‐L could be an alternative to CaCl₂ in the pretreatment of fruits prior to drying as it offers improved quality.     

Reduction of sodium and increment of calcium and ω‐3 polyunsaturated fatty acids in dry fermented sausages: effects on the mineral content,lipid profile and sensory quality

BACKGROUND: A combined technological approach was applied in the development of healthier dry fermented sausages: a partial substitution of the pork back fat by pre‐emulsified linseed oil and a partial replacement of sodium chloride with calcium ascorbate at two different levels, leading to low amounts of salt (14gSalt and 10gSalt, with 14 g and 10 g NaCl per kg of mixture, respectively). RESULTS: The developed products (14gSalt and 10gSalt) showed adequate results for a_w (0.85 and 0.87) and pH (4.98 and 5.21), and low lipid oxidation values (1.4 × 10^?4 and 1.5 × 10^?5 g malondialdehyde (MDA) kg^?1). The lipid modification led to a significantly higher supply of ω‐3 (23.3 g kg^?1) compared to the control (3.2 g kg^?1). Simultaneously, reductions of 38% and 50% in sodium content and a calcium supply of 4 and 5.2 g kg^?1 were achieved in the 14gSalt and 10gSalt formulations, respectively, compared to the control products (26 g salt and 0.87 g kg^?1 Ca). Instrumental analysis of colour and texture and sensory studies demonstrated that the organoleptic quality of the new formulations was similar to that of traditional products. CONCLUSIONS: The developed dry fermented sausages showed healthier properties than traditional ones owing to their reduced sodium and higher calcium content and a significant supply of ω‐3 fatty acids. © 2012 Society of Chemical Industry     

Effect of Osmotic Dehydration and Pectin Edible Coatings on Quality and Shelf Life of Fresh-Cut Melon

The aim of this work was to investigate the influence of osmotic dehydration and pectin edible coating on quality parameters of fresh-cut melon. Fruits were osmodehydrated in 40°Bx sucrose solution containing 0.5% calcium lactate or dipped in 0.5% calcium lactate solutions. Then, samples were coated with 1% pectin. Melon pieces dipped in sanitizing solution (nontreated sample) were used as control. Weight loss, respiration rate, firmness, color parameters (lightness, chroma, and whiteness index), sensory acceptance, microbial growth, and structural changes of fruits were evaluated during storage at 5 °C for 14 days. The shelf life of the control sample was limited to 9 days due to microbial growth and sensory rejection, while treated samples showed a shelf life of 14 days. Higher preservation of firmness in coated samples was attributed to the action of calcium salt on melon structure, causing a strengthening of the cell wall. Calcium lactate also inhibited microbial growth along storage, improving microbiological stability of fresh-cut melon. The use of calcium lactate dips and pectin edible coatings hindered weight loss and maintained fruit color characteristics during the storage time. However, these pretreatments probably masked melon taste, reducing the sensory acceptance scores at the end of shelf life study. The combination of osmotic dehydration and pectin coatings was a good preservation alternative for fresh-cut melon, since it improved fruit sensory acceptance, promoting the reduction of product respiration rate, as well as the maintenance of quality parameters during 14 days.     

Enhancement of freezing stability in mashed potatoes by the incorporation of kappa‐carrageenan and xanthan gum blends

BACKGROUND: To ameliorate the detrimental effects of freezing and thawing, blends of κ‐carrageenan (κ‐C) and xanthan gum (XG) were added to frozen/thawed mashed potatoes (F/TM potatoes). Product was tested by textural and rheological measurements, other quality parameters and sensory analyses. The effects of variation in levels of κ‐C (1.5–4.5 g kg^?1) and XG (0.5–2.5 g kg^?1) concentrations were studied. RESULTS: Instrumental measurements and sensory analyses indicated that 4.5 g kg^?1κ‐C and 2.5 g kg^?1 XG provided better thickening. κ‐C provided the appropriate texture, while XG imparted creaminess to the product, which could be associated with an increase in the amount of XG–water interactions. Addition of κ‐C had a major impact on textural properties, gel strength and viscoelastic behaviour, whereas XG influenced steady properties, colour, water‐holding capacity (WHC) and overall acceptability (OA). CONCLUSION: The OA of F/TM potatoes was mostly improved by addition of cryoprotectant blends, which is ascribed to improvement of F/TM potatoes texture by retarding starch retrogradation, increasing WHC, and enhancing the principal characteristics determining consumer acceptance. Creaminess was the most crucial factor for OA of the products. Addition of both polysaccharides at a low concentration (each cryoprotectant at 1.5 g kg^?1) is recommended. Copyright © 2009 Society of Chemical Industry     

Sensory properties of some synthetic high‐intensity sweeteners in water solutions

BACKGROUND: When sucrose is eliminated from products to meet consumers' demand for calorie‐free products and substitutes are used, sweetness becomes an important characteristic. The objective of this study was to compare sensory properties of four sucrose substitutes: aspartame, acesulfame K, sodium saccharin and sodium cyclamate in water solutions. RESULTS: The lowest concentrations of sweeteners such as 0.35 g kg^?1 for aspartame and acesulfame K showed an equi‐sweet level relative to approx. 55 g kg^?1 aqueous sucrose solution, whereas 2.3 g kg^?1 sodium cyclamate and 0.4 g kg^?1 sodium saccharin relative to approx. 65 g kg^?1. Aspartame had almost the same sweetness potency as acesulfame K, whereas the remaining sweeteners differed completely. The four sweeteners showed their specific sensory profiles. Besides the characteristics of sweetness and bitterness, metallic and astringent attributes plus warming and cooling effects were found. CONCLUSIONS: Of the four sweeteners, aspartame and sodium cyclamate can be considered as the best sucrose substitutes due to their similar sensory profiles to the sucrose. The data showing the interdependence between sweetness intensity of the sweeteners and sucrose are useful as a quick and easy indicator of the sweetener amount having equi‐sweet levels relative to sucrose. Copyright © 2009 Society of Chemical Industry     

Improvements in Canned Lowbush Blueberry Quality

Individually quick frozen lowbush (wild) blueberries (Vaccinium angusrifolium) were canned with 0, 1500, or 3000 ppm calcium from chloride or lactate salts and 0, 0.25, or 0.50% citric acid in water. Physical and pH changes were measured at 0, 6, and 12 mo, and sensory evaluations were made at 3 and 9 mo post-canning. Calcium increased firmness and berry calcium content. Calcium chloride and citric acid reduced pH and increased hue angle and off-flavor; calcium lactate increased drained weight and pH but reduced hue. Response surface methodology predicted changes in calcium lactate-treated berries, but not CaCl₂-treated berries. Optimal conditions were 1200–1800 ppm calcium lactate at 3–6 mo storage.     

Comparison of calcium lactate with chlorine as a washing treatment for fresh‐cut lettuce and carrots: quality and nutritional parameters

The efficacies of calcium lactate and chlorine washing treatments of fresh‐cut lettuce and carrots were compared during storage at 4 °C over 10 days. The gas composition of packages, colour, enzyme activity, texture, sensory attributes, microflora and levels of ascorbic acid and carotenoids were evaluated at 1, 3, 7 and 10 days. Calcium lactate treatment was not significantly different to chlorine treatment (p < 0.05) in terms of maintaining colour, texture and acceptability of fresh‐cut lettuce and carrots during the entire storage period. The washing treatments did not affect levels of ascorbic acid of fresh‐cut lettuce or carrots. Carotenoid levels were higher in calcium lactate‐treated carrots than chlorine‐treated samples at the end of storage. Mesophilic, psychrotrophic and lactic acid bacteria counts were not significantly different between treatments for both vegetables. Copyright © 2005 Society of Chemical Industry     

Post-harvest application of diphenylamine and ethoxyquin for the control of superficial scald on Bramley's seedling apples

Recent changes in the antioxidant regulations in the UK and the need to evaluate the effectiveness of scald control chemicals in the presence of other post-harvest chemicals led to a comparative study of the effects of diphenylamine (DPA) and ethoxyquin on scald development in Bramley's Seedling apples. A range of concentrations (1000–4000 mg litre^?1 a.i.) of DPA completely controlled scald on Bramley apples kept in controlled atmosphere storage for 241 days; ethoxyquin at equivalent rates was less effective. Only partial control of scald was achieved with 500 mg litre^?1 a.i. DPA. None of the treatments injured the fruit. Control of scald by 2000 mg litre^?1 a.i. DPA or ethoxyquin was not impaired by adding thiophanate-methyl (l g litre^?1 a.i.) or calcium chloride (10 g litre^?1) although the measure of control was reduced when both fungicide and calcium chloride were added. Calcium chloride caused lenticel injury which was aggravated by adding ethoxyquin but reduced by incorporating DPA. The concentrations of ethoxyquin and DPA residues on the fruit immediately after treatment were within the limits required by UK legislation (see reference 1) of 3 mg kg^?1 and 10 mg kg^?1, respectively, even where 4000 mg litre^?1 had been applied. An initial residue concentration of 2.3 mg kg^?1 DPA was associated with complete control of scald. Residue levels, particularly of DPA, declined rapidly during the first month of storage.     

Sweet potato-based pasta product: optimization of ingredient levels using response surface methodology

Sweet potato flour was used for the development of a pasta product. The system known as response surface methodology was used to analyse the effect of sweet potato flour, soyflour, water, Arabic gum and carboxy methyl cellulose (CMC) on quality responses (sensory, solids loss and hardness) of the pasta product. A rotatable central‐composite design was used to develop models for the responses. Responses were affected most by changes in soyflour and gum levels and to a lesser extent by sweet potato flour and water levels. Individual contour plots of the different responses were superimposed and regions meeting the maximum sensory score (33.8), minimum solids loss (16.6%) and maximum texture hardness (5616 g) were identified at 674 g kg^?1 sweet potato flour, 195 g kg^?1 water, 110 g kg^?1 soyflour, 10.6 g kg^?1 Arabic gum and 10.1 g kg^?1 CMC levels.     

Osmotic Dehydration of Pineapple with Impregnation of Sucrose, Calcium, and Ascorbic Acid

Mass transfer was evaluated during osmotic dehydration of pineapple in solutions with until four components aiming to investigate the solutes concentration influence on impregnation. In the first step, the experimental trials for optimization of solution concentration were based on 2³ factorial design. In the second step, effective diffusion coefficients were determined. Equations representing the influence of the concentration of sucrose, calcium lactate, and ascorbic acid in osmotic solutions on water loss and gains of sucrose, calcium, and vitamin C were found. Results showed that both calcium lactate and sucrose concentration affected calcium and sucrose gain. On the other hand, only vitamin C gain was significantly affected by the ascorbic acid concentration in the studied concentration range. However, when comparing diffusivities in pineapple immersed in sucrose solutions, with and without calcium lactate, with and without ascorbic acid, it was possible to verify that diffusivities of water, sugar, and calcium increased in presence of ascorbic acid in solution. Calcium in solution diminished the water and sucrose diffusivities. High calcium and vitamin C contents were obtained in 1 h immersion in the solutions studied.     

Effect of calcium on the storage life of oro (Antiaris africana)

The effects of calcium on the ascorbic acid, chlorophyll, titratable acidity and texture (firmness) of stored oro (Antiaris africana (Mill)) friuits (average weight 100 g ) were studied. Three groups of the fruits were dipped in 20 g litre^?1, 40 g litre^?1 CaCl₂ solutions and deionised water respectively for I0 min. The fourth group, which was untreated, served as the control and was also packaged in heat-sealed cellophane bags. The fruits were displaced and stored at ambient temperature (28 ± 2°C). The calciumtreated fruits which kept better were firmer and had a slight colour change (chlorophyll) which also produced a progressive increase in ascorbic acid level during storage. The titratable acidity of the fruits did not fluctuate as signijcantly as that of the untreated (control) fruits.     

Pectin and calcium chloride treatment for low‐fat fried green gram splits

Fried green gram (Phaseolus mungo L) splits are a traditional savoury relished by consumers of all age groups as an anytime snack. The high oil content in such products is of concern owing to its association with obesity and related health disorders. The present work evaluates the effect of soaking green gram splits in calcium chloride solution (2.5–10 g kg^?1) for 3 h followed by air drying and a subsequent dip in 10–30 g l^?1 pectin solution for 10 min, again followed by air drying, on the oil content in the fried product prepared from them. After frying in groundnut oil at 170 ± 5 °C for 2 min, the oil content in the pretreated fried product was reduced to 211.7 g kg^?1, compared with 335 g kg^?1 for the untreated control. Attempts to further reduce the oil content by applying a second coating of pectin were unsuccessful. Copyright © 2005 Society of Chemical Industry     

Effects of sodium caseinate‐ and milk protein concentrate‐based edible coatings on the postharvest quality of Bing cherries

Bing cherries were coated with sodium caseinate‐ or milk protein concentrate‐based edible coatings. Besides the proteins (100 g kg^?1), the coating formulations also included glycerol (about 300 g kg^?1 protein) and either beeswax or a stearic–palmitic acid blend at a concentration of 0, 100 or 300 g lipid phase kg^?1 of protein. All coatings, especially those containing 300 g kg^?1 stearic–palmitic acid blend, successfully reduced water loss of the fruits. The edible coatings had a beneficial effect on the sensory quality of the cherries, and there were significant (p < 0.05) effects of the coating treatments on soluble solids, titratable acidity and pH. Copyright © 2004 Society of Chemical Industry     

Effects of Modified Atmosphere Packaging on the Physicochemical Characteristics of Ciku ( Achras sapotaL) at Various Storage Temperatures

The physicochemical changes in ciku during storage at various temperatures and the effect of various techniques of modified atmosphere packaging (MAP) at 5, 10, 15°C and ambient were examined by monitoring fruit texture, weight loss, soluble solids content, pH, sucrose, fructose, glucose, pectin, tannin, ascorbic acid and microbial infection. Under MAP, ciku could be stored for 4 weeks at 10°C and 3 weeks at 15°C, while without MAP the storage life was shorter by 1 week. Packaging in low-density polyethylene film (LDPE) was highly effective in maintaining the texture and weight of cold-stored fruits. Fruits stored at 5°C experienced chilling injury, observed as their inability to ripen properly, even after 3 days at room temperature in the presence of 50 g kg⁻¹ calcium carbide. The ascorbic acid content was highest in vacuum-packed fruits followed by the other LDPE packagings. LDPE packaged fruits also received the highest sensory scores for taste, colour, texture and overall acceptability in cold-stored ciku. The unsealed nature and heating involved in shrink wrapping did not favourably affect the storage life of ciku. MAP alleviated the chilling injury which occurred in ciku stored at 10°C but not at 5°C.     

Effects of legume processing on calcium,iron and zinc contents and dialysabilities

Legumes are a good source of calcium, iron and zinc, but are also a source of phytates and dietary fibre components that can negatively affect the bioavailability of these minerals. To estimate the latter, an in vitro dialysis method can be applied that gives the dialysability of a mineral as an estimate of its availability for absorption. Calcium, iron and zinc contents and dialysabilities in three legumes (beans, chickpeas and lentils) and the effects of cooking treatments and industrial processing on these parameters were studied. Beans had the highest calcium content (1.54 g kg^?1 dry matter (DM)) and chickpeas the lowest iron content (46.9 mg kg^?1 DM), whilst the zinc contents were similar in all three raw legumes (33.7–36.9 mg kg^?1 DM). Traditional and microwave cooking reduced the mineral contents by 9.7–36.4% for calcium, 14.2–31% for iron and 11.1–28.9% for zinc. The dialysabilities of calcium with respect to the values for the raw products were also reduced by these cooking techniques. Industrially processed legumes had higher dialysabilities of calcium, iron and zinc than traditionally or microwave cooked legumes. © 2001 Society of Chemical Industry     

Fat reduction in emulsion sausage using an enzyme‐modified potato starch

BACKGROUND: A heat‐stable amylase‐modified potato starch (MPS) was prepared and used as a fat replacer in reduced‐fat emulsion sausages. The effects of fat level (50, 150 and 300 g kg^?1) and MPS addition (20 and 40 g kg^?1) on energy, colour, sensory, and textural properties of emulsion sausages were investigated. RESULTS: The addition of 20 or 40 g kg^?1 of MPS in reduced‐fat sausage (50–150 g kg^?1 fat) reduced total energy (15.1–49.4%), increased lightness, but lowered redness of the products (P < 0.05). The 150 g kg^?1 or 50 g kg^?1 fat sausages containing 20 g kg^?1 MPS had a similar hardness to the 300 g kg^?1 fat control (P > 0.05). Sensory evaluation indicated that the presence of MPS in reduced‐fat sausages increased (P < 0.05) the product's tenderness. CONCLUSION: Overall, the 150 g kg^?1 fat emulsion sausages with 20 g kg^?1 MPS were comparable to the 300 g kg^?1 fat control sausage in colour, texture profile, and sensory properties, but was lower in energy, suggesting that the MPS can be used as a potential fat replacer in sausage products. Copyright © 2008 Society of Chemical Industry