Changes In Water Holding Capacity Research Articles

Mass transfer kinetics of ultrasonic- and vacuum-ultrasonic-assisted static brine of chicken breast (Pectoralis major).

The aim of this study was to investigate the effect of different ultrasound treatment (UT) conditions (Control, UT-150, UT-300, UT-450, Vacuum-UT-150, Vacuum-UT-300, Vacuum-UT-450) on the brining kinetics and meat quality of chicken breast. The results showed that vacuum-ultrasonic-assisted treatment greatly accelerated the transfer of moisture and NaCl, and the highest yield was obtained by ultrasonic power of 450W. The mass transfer kinetics (k1 and k2) were significantly related to vacuum pretreatment and ultrasonic power. The values of k1 for total and moisture weight changes decreased with the increase of ultrasonic power, whereas the values of k2 increased with vacuum pretreatment. The application of ultrasound treatment with vacuum improved the NaCl effective diffusion coefficients (De) from 1.189×10-9 to 1.308-1.449×10-9 m2/s, and the highest De was found with Vacuum-UT-450. The treatment of ultrasound and vacuum can reduce shear force and enhance the water-holding capacity (WHC). According to the analysis of water distribution, vacuum and ultrasound could decrease the T23 values, indicating that the mobility of water decreased. The result of microscopic observation further supported that the disruption of myofibrils was related to the tenderness and WHC changes, which was caused by vacuum and ultrasound treatment. Thus, Vacuum-UT brining could be employed as an emerging technology for improving the efficiency of brining and meat quality of other meat. PRACTICAL APPLICATION: Vacuum-ultrasonic-assisted static brine is an effective and feasible treatment to replace tumbling treatment for maintaining the integrity of the muscle bundles and accelerating the brining rate.

Effects of ageing on longissimus thoracis et lumborum muscle of local beef

The ageing process significantly influences the quality parameters of beef, including water holding capacity (WHC), drip loss, tenderness, pH, and cooking loss. This study aimed to investigate the impact of ageing on these parameters and establish ageing as a valuable method for enhancing beef (LTL muscle) tenderness while minimally affecting other quality attributes. Using beef samples subjected to ageing periods of 1 day, 3 days, and 7 days, and 9 days, a comprehensive analysis was conducted to assess changes in WHC, drip loss, tenderness, pH, and cooking loss over time. The research findings revealed nuanced variations in these parameters across the ageing periods. While WHC, drip loss, pH, and cooking loss exhibited minimal changes throughout the ageing process, a notable improvement in tenderness was observed with increasing ageing duration. This enhancement in tenderness underscores the effectiveness of ageing in softening beef muscle fibers and improving eating quality. Moreover, the study explored the underlying mechanisms driving the observed changes in beef quality during ageing, including proteolysis, collagen degradation, and moisture redistribution. Understanding these mechanisms is crucial for optimizing ageing conditions and maximizing the beneficial effects on beef tenderness. Overall, the findings of this study contribute to the body of knowledge on the effects of ageing on beef quality parameters and provide practical insights for meat industry professionals and stakeholders. By establishing ageing as a valuable process for enhancing beef tenderness, this research has implications for meat processing practices, product development, and consumer satisfaction.

Development of a Ready-to-Eat Fish Product Enriched with Fish Oil Entrapped in a κ-Carrageenan Egg White Fish Protein Hydrolysate Dry Powder.

This work describes the development of a ready-to-eat (RTE) product based on an equal mixture of fish mince from three undervalued fish species with different fat contents and protein gelling capacity, which was enriched with fish oil entrapped in a κ-carrageenan egg white fish protein hydrolysate powder, obtained by either spray drying (SD) or heat drying (HD) at 80 °C (HD80). Previously, the spray-dried (SD) powder and heat-dried powders obtained at 45 °C, 60 °C and 80 °C (HD45, HD60 and HD80) were characterised in terms of water solubility, lipid oxidation (TBARS), hygroscopicity and ζ potential. All HD powders showed higher hygroscopicity and lower TBARS than the SD powder. The dry powder was incorporated into a blend composed of salt-ground batter and raw mince to improve binding and textural properties. Changes in water-holding capacity, colour, shear strength and microorganisms were monitored during the processing steps. The RTE product presented a high protein content and a noticeable amount of long-chain ω-3 fatty acids. The use of undervalued fish species together with fish oil and a protein hydrolysate from fish waste contribute to improving the sustainability of fishery resources, being conducive to obtaining a potentially functional RTE product.

돈육 등심, 우육 등심, 닭 가슴살의 습식 숙성 기간에 따른 이화학적 특성 변화

In this study, the physicochemical characteristics of pork loin, beef loin, and chicken breast with various wet aging periods were analyzed to derive an appropriate wet aging period for each livestock. Pork loin and chicken breast were stored at 4°C for 0, 1, and 2 weeks, and beef loin was stored at 4°C for 0, 1, 2, 3, and 4 weeks, and proximate compositions, water holding capacity (WHC), cooking yield, shear force, volatile basic nitrogen (VBN), thiobarbituric acid reactive substances (TBARS), and sensory evaluation were analyzed. In case of WHC, pork loin was the highest in weeks 0 and 1, and beef loin showed similar values in weeks 0 to 2, and increased in weeks 3, 4 (p<0.05). Chicken breast showed no significant changes of WHC. Cooking yield showed no significant differences during the aging period in all samples. All samples had the lowest shear force at the 2nd week of aging during all aging periods. In case of VBN, pork loin showed an increasing tendency in weeks 0 and 2, and chicken breast were significantly increased (p<0.05), beef loin showed no significant changes, and TBARS, pork loin and chicken breast showed no significant changes in weeks 1 and 2, beef loin showed similar values in weeks 1 to 3. In the sensory evaluation, all samples showed the best results in weeks 2. As a result, the most appropriate wet aging period is considered to be 2 week for pork loin, beef loin and chicken breast.

Changes in Water Holding Capacity and Shear Force in Fallow Deer Muscles during Ageing

The aim of the study was to determine changes in water-holding and water-binding capacities in relation to the tenderness of fallow deer semimembranosus (SM) and longissimus thoracis et lumborum (LTL) muscles during ageing. In the study, muscles obtained from 18-month-old farm-raised fallow deer bucks were used. The quality of the meat was determined during ageing for 48 h, 168 h, and 288 h post slaughter. It was noted that ageing had a negative effect on water retention in fallow deer meat. It decreased the ability of meat tissue to bind added water (p < 0.01) and increased cooking losses (p < 0.01), though it also increased tenderness (p < 0.01). Generally, SM showed lower (p < 0.001) tenderness than LTL. SM and LTL muscles were similar in terms of free water content, ability to bind added water, and cooking losses (p > 0.05). The way the meat was heated (cooked in water vs. roasted in the dry air) affected only cooking losses (p < 0.05), which were higher in roasted samples but had no effect either on volume loss or meat tenderness. In conclusion, the main factor affecting the water holding and binding capacities, as well as fallow deer meat tenderness, is ageing. The time enough to obtain tender meat is 168 h for LTL, whereas SM should be aged for 288 h.

Physicochemical properties and structural changes of chicken breast meat subjected to radio frequency tempering combined with conventional thawing treatments

Being able to thaw frozen meat in a reasonable time without impairing quality is crucial for industry and households. Radio frequency (RF) techniques have been used to defrost frozen foods. The influences of RF (50 kW, 27.12 MHz) tempering combined with water immersion (WI, 20°C) thawing (RFWI) or air convection (AC, 20°C) thawing (RFAC) on the physicochemical and structural changes of chicken breast meat were investigated, and the results were compared with those of the fresh meat (FM) and the meat samples subjected to WI and AC only. The thawing processes were terminated when the core temperatures of the samples reached 4°C. The results indicated that AC was the most time-consuming technique, whereas RFWI required the least amount of time. The moisture losses, contents of the thiobarbituric acid-reactive substance, total volatile basic nitrogen, and total viable counts of the meat subjected to AC were higher. Relatively less changes in water-holding capacity, coloration, oxidation, microstructure, protein solubility, and high sensorial acceptance were observed for RFWI and RFAC. This study demonstrated that the meat thawed using RFWI and RFAC was of satisfactory quality. Therefore, the RF techniques can be effective alternatives to the time-consuming conventional thawing methods and benefit the meat industry.

Myofibrillar protein composite gels: effect of esterified potato starch, lard and peanut oil on the gel properties.

Heat-induced composite gels were prepared with 20 g kg-1 myofibrillar protein (MP) sol, 20 g kg-1 modified starch and 100 g kg-1 lipid pre-emulsified by MP in 0.6mol L-1 NaCl, at pH6.2. The effects of esterified potato starch (EPS) and emulsified lipid (lard or peanut oil) on the rheology, texture properties and nuclear magnetic resonance characterization of MP gel were evaluated. The addition of starch and lipid significantly improved the gel strength and water holding capacity (WHC) of the MP gel. Analysis of the relaxation time compared with the WHC tests showed that the variation range of the transverse T22 relaxation time of a gel was positively proportional to changes in WHC of the composite gel, and the lower the T22 relaxation time, the better the WHC of composite gel. Moreover, MP gel with starch and emulsified lard added at the same time has the lowest T2 relaxation time, and also the best WHC of the gel. Environmental scanning electron microscopy showed that emulsified oil droplets embedded the gaps in the protein network, and the gelatinized starch contributed to restrict the oil droplet size, resulting in thicker MP gel. Emulsified lipid and modified starch have an important influence on the rheology and microstructure of MP gels, indicating the subtle interaction between starch, lipid and protein. The results suggest the potential feasibility of modified starch and vegetable oil to improve the textural properties in comminuted meat products. © 2021 Society of Chemical Industry.

An understanding of the changes in water holding capacity of rehydrated shiitake mushroom (Lentinula edodes) from cell wall, cell membrane and protein

Water holding capacity (WHC) is an important factor for the evaluation of rehydrated shiitake mushroom as WHC largely affects sensory attributes. Here, WHC of the rehydrated shiitake mushroom as affected by different hot-air drying temperature was investigated from aspects of cell membrane integrity, status of cell wall fibrous material and protein denaturation. Among the three factors, protein denaturation played the most important role to affect the WHC of rehydrated mushroom as protein denaturation was closely related to the maintenance of porous structure after rehydration. Effect of status of the cell wall fibrous material to the WHC changes was relatively weak and was largely correlated to the WHC changes at high temperature (>80 °C). Cell membrane was unlikely to contribute to WHC changes of the rehydrated shiitake mushroom due to the loss of integrity.

Effects of high hydrostatic pressure on color, texture, microstructure, and proteins of the tilapia (Orechromis niloticus) surimi gels.

The tilapia (Orechromis niloticus) surimi gels were prepared with high hydrostatic pressure (0, 100, 200, 300, and 400 MPa for 15 min) treatments to investigate the changes in water-holding capacity, color, gel strength, microstructure, texture, and proteins of the gels. Compared it with cooked gel (40°C/30 min + 90°C/30 min). The whiteness of heat-induced and HHP-induced gels were significant (p < .05) higher than that of untreated samples. The gels formed by pressurization were dense and flexible, and formed by cross-linking based on hydrogen bonding. SDS-PAGE patterns showed no major change in the actin and tropomyosin protein profiles of gels induced by HHP-300. Raman spectroscopy confirmed disulfide bonds played an important role in gel formation. A lower intensity ratio observed in HHP-induced protein supported the tyrosine residues involved in hydrogen bond formation. The changes of secondary structure suggested decreased α-helix content and increased β-sheet.

Storage time prediction of glazed frozen squids during frozen storage at different temperatures based on neural network

ABSTRACT In this study, quality changes in water-holding capacity, weight loss, color, texture properties, and total sulfhydrylcontent of glazed frozen squids during frozen storage at −5, −10, −20, −30 and −40°C, were determined. In addition, backpropagation neural network (BP-NN) and long short-term memory neural network (LSTM-NN) model were established to predict storage time of glazed frozen squids, and then these two models were performed with a comparative study. The results showed that the influence on the quality of the squids during frozen storage at different temperatures had significant difference (P < .05), and at the lower storage temperatures, the declined rate of squids’ quality was slower, especially. However, changes in the total SH content of squid stored at −30 and −40°C, were not significant differences in the first 60 days. The squid frozen at −5°C for 80d, reached the end of the shelf life. Both BP-NN and LSTM-NN model ware reliable models for predicting the storage time of glazed frozen squid. Experimental results of the LSTM-NN model provided an improvement in the accuracy of prediction compared with those obtained by using the BP-NN model, in which the mean absolute percentage error (MAPE) was 5.01% that was lower than the results by BP-NN model (7.67%). However, the LSTM-NN model had some shortcomings in terms of training time compared with the BP-NN model. The use of LSTM-NN provides a technique to predict accurately the storage time of glazed frozen squid.

Wheat batter physical properties as influenced by starch/flour types and egg contents

Batter liquid–solid phase interactions can play a critical role in determining the functionality, including adherence, appearance and texture of end use coated product. Batter chemical composition is a key factor affecting batter characteristics. The effect of substituting wheat flour with fractions of rice flour, native corn starch, modified waxy corn starch, tapioca starch and lupine flour ranging from 26 to 56% of the solid phase and egg levels ranging from 6 to 35% of the liquid phase on the rheological properties of batter systems was studied. Results indicated that lupine flour had the greatest water holding capacity (WHC) ranging from 93.9 to 119.3% of various lupine flour percent to egg levels used. Flow behaviour index of batter flour treatments ranged from 0.91 to 1.87; values that were significantly (P < 0.05) greater than a 100% control wheat flour. Consistency coefficient of treatments ranged from 0.01 to 0.37 mPa sn; values that were significantly lower than wheat flour (i.e., 5 mPa sn). Egg level used in this study had minimal effect on treatment rheological properties. The changes in WHC and viscoelastic properties of treatments were attributed to changes in protein and fibre contents and structure as a result of replacing wheat flour with starch/flour. Protein–starch–lipid matrix formation and variation in water absorption kinetics of treatments most probably wrought batter functionality. The increase in pasting properties with the increase in starch/flour contribution suggested an increased contribution of starch in forming a net effect of batter treatments pasting viscosities. Results of this study provide vital information for the potential use of starch types to enhance the rheological properties of coating applications including adhesion and water holding capacity of substituted batter treatment.

Effect of cooking on physicochemical and structural properties of jumbo squid ( Dosidicus gigas ) muscle

Jumbo squid (Dosidicus gigas) is an important commercialized fishery in Mexico; however, during its post-catch processing, several physicochemical changes occur in flesh, which could result in texture modifications. In this research, changes in water-holding capacity, protein solubility (PS), firmness, fibrils microstructure, and color of squid muscle (mantle, fins, and arms) during cooking (30 min at 100 °C) were evaluated. Throughout cooking were exhibited different shrinkage and weight loss behavior among three anatomical regions (p < .05). After cooking, PS of muscle from fins and arms remained similar, meanwhile, mantle muscle PS decreased 75%. Shear force (SF) magnitude order (p < .05) registered in fresh muscle was fins > arms > mantle, whereas at ending cooking, mantle muscle required the lowest SF. Microscopic analysis revealed a major quantity of collagen fibers in fins and arm muscle suggesting its possible relation to their hardness, in both fresh and cooked state. Practical applications Jumbo squid (Dosidicus gigas) is an important marine resource in Mexico and many Asiatic and European countries. Its muscle (fins, arms, and mantle) edible items are commercialized and consumed in fresh, brined, and cooked presentations. Squid muscle protein structures (fibril and stromal) are organized different than fish as well as beef, pork and poultry; therefore its textural, physicochemical and sensorial (quality parameters) changes induced by cooking are distinctive. Squid meat acceptance by consumers is related mainly by texture than the taste or color attributes. Therefore, from economic point of view of domestic and large-scale markets, the establishment of best cooking conditions of squid became essential.

Changes in Protein Oxidation, Water-Holding Capacity, and Texture of Bighead Carp (Aristichthys Nobilis) Fillets Under Chilled and Partial Frozen Storage

ABSTRACTThis study aimed to evaluate the contribution of protein oxidation to the changes in the water-holding capacity (WHC) and texture of bighead carp (Aristichthys nobilis) fillets under chilled and partial frozen storage (4°C and −3°C). The results indicated that less protein oxidation occurred to fillets at −3°C than at 4°C, which was reflected by the higher value of salt-soluble protein contents (SSP), total sulfhydryl content (SH), Ca2+-ATPase activity, lower water-soluble protein contents (WSP), total disulfide content (SS), and surface hydrophobicity (So-ANS). However, the fillets had better WHC and texture at 4°C, as well as lower drip loss and higher centrifugal loss, hardness, and springiness. A significant linear relationship existed between protein oxidation parameters with WHC and texture characteristics for fillets under both types of storage, but the process of freezing and then thawing, instead of protein oxidation, was the main factor affecting the texture and WHC of fillets at −3°C.

Change in Water-Holding Capacity in Mushroom with Temperature Analyzed by Flory-Rehner Theory

The change in water-holding capacity of mushroom with the temperature was interpreted using the Flory-Rehner theory for swelling of polymeric networks, extended with the Debye-Huckel theory for electrolytic interactions. The validity of these theories has been verified with independent sorption measurements. The change in water-holding capacity with temperature could be quantified as changes in three model parameters: the Flory-Huggins interaction parameter between the biopolymers and the aqueous solvent phase, the cross-link density of the network, and the biopolymer volume fraction at the relaxed state. The elastic pressure is analyzed using the Flory-Rehner theory, which is traditionally used to describe the swelling of polymers. From the explicit knowledge of the elastic pressure, we can determine how model parameters, such as the cross-link density, depend on temperature. We argue that the dependencies of model parameters can be understood as a consequence of protein denaturation. Having knowledge on how all contributions to the swelling pressure depend on temperature, and composition, we can compute the water-holding capacity of mushroom for a wide range of temperatures and mechanical loads.

Effect of free-range days on a local chicken breed: Growth performance, carcass yield, meat quality, and lymphoid organ index

An experiment was conducted to evaluate the effect of free-range days on growth performance, carcass yield, meat quality, and lymphoid organ index of a local chicken breed. In total, 1,000 one-day-old male Suqin yellow chickens were raised for 21 d. On d 21, 720 birds with similar BW (536 ± 36 g) were selected and randomly assigned to free-range treatment at 21, 28, 35, and 42 d of age (assigned to free-range treatment for 21, 14, 7, and 0 d, respectively). Each treatment was represented by 5 replicates (pens) containing 36 birds (180 birds per treatment). All the birds were raised in indoor floor pens measuring 1.42 × 1.42 m (2 m2, 18 birds/m2) in conventional poultry research houses before free-range treatment. In the free-range treatment, the chickens were raised in indoor floor houses measuring 3 × 5 m (15 m2, 2.4 birds/m2). In addition, they also had an outdoor free-range paddock measuring 3 × 8 m (24 m2, 1.5 birds/m2). The BW of birds after being assigned to free-range treatment for 7 d decreased significantly compared with that in the conventional treatment (P < 0.05). However, there was no effect of the free-range days on the BW at 42 d of age (P > 0.05). The daily weight gain, feed per gain, daily feed intake, and mortality from 21 to 42 d of age were unaffected by free-range days (P > 0.05). At 42 d of age, the breast yield increased linearly with increasing free-range days (P < 0.05), whereas the thigh, leg, thigh bone, and foot yields decreased linearly (P < 0.05). The lung yield showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The water-holding capacity of the thigh muscle decreased linearly with increasing free-range days (P < 0.05), whereas there was no significant difference in the meat color, shear force, and muscle pH (P > 0.05). The absolute thymus weight and thymus:BW ratio showed a significant increasing and then decreasing quadratic response to increasing free-range days (P < 0.05). The findings of this study suggest that increasing free-range days advantageously affects breast yield, but decreases thigh, leg, thigh bone, and foot yields as well as the water-holding capacity of thigh. No evidence was found that increasing free-range days caused changes in growth performance, meat quality, and lymphoid organs except for changes in water-holding capacity and thymus.

Kinetics of Release of Water and Nutrients from Codfish (Gadus morhua L.) through a Heavy-Salting

Through the typical 6 days heavy-salting, codfish releases 25% (w/w) of its physiological water due to the incorporation of high amounts of salt, 20% (w/w). Besides changes in water-holding capacity, major effects imparted by salt are modifications in muscle proteins conformation with subsequent denaturation and loss, and release of free amino acids. Water is liberated from codfish according to a power-law kinetics, which describes biological reactions under molecular crowding. Proteins and amino acids are released by pseudo-first and pseudo-second order kinetics, which describe proteolysis. Despite the loss of nutrients through salting, the nutritional value of codfish can be considered unchanged. A reduction by weight of 0.45% in muscle proteins, 1.24% aspartic acid, 1.4% glutamic acid, 2% arginine, 11% creatine, 0.2% glycine, 0.5% lysine, 0.4% methionine, 0.3% phenylalanine, 3.4% taurine and 3% tryptophan is noticed. Practical Application Codfish (Gadus morhua L.) has a high nutritional value and is almost exclusively constituted of proteins on a dry base. Salt-cured codfish continues to be widely produced thanks to the simplicity of the process and because it is highly appreciated by consumers. Heavy-salting, a dry-salting, induces important changes in the muscle structure of codfish, leading to a loss of nutrients such as muscle proteins and free amino acids. Nevertheless, the nutritional value of codfish is unchanged. Kinetics found for the release of nutrients from codfish might be likely extended to other white fish undergoing the same salting process.

Reduction in fat uptake of doughnut by microparticulated wheat bran

Wheat flour–microparticulated wheat bran (MWB) mixture and composites were prepared, and their potential as an oil repellent was evaluated in doughnuts. As MWB content increased, the oil-holding capacity decreased, and there were significant changes in water-holding capacity (p < 0.05). As MWB content increased, the fat content of doughnuts decreased. In addition, the wheat flour–MWB composite was more effective for preventing fat uptake than the wheat flour–MWB mixture. The hardness of the composite was higher than the mixture, although volume and weight decreased and surface colour became darker than that of the mixture. As the proportion of wheat bran in the doughnut formulation increased, the inner crust achieved a uniform cell size and cellular integrity was improved. Based on these data, wheat flour–MWB composites are appropriate for use in doughnut formulas with low fat uptake.

Effect of hydroxycinnamic acids on lipid oxidation and protein changes as well as water holding capacity in frozen minced horse mackerel white muscle

The antioxidant effectiveness of different hydroxycinnamic acids for inhibiting the formation of off-flavours associated to rancidity in minced frozen horse mackerel white muscle stored at −10 and −18 °C was studied. The influence of lipid oxidation on protein aggregation, protein denaturation and water holding capacity was also determined. Caffeic acid, o-coumaric acid and ferulic acid were the antioxidants tested. The order of antioxidant effectiveness was caffeic acid > ferulic acid > o-coumaric acid accordingly with previous results obtained in chilled horse mackerel. A strong dependence of antioxidant effectiveness to the ratio lipid/antioxidant concentration was observed. There was no evidence to suggest that antioxidants reduce protein aggregation or water holding capacity changes. Protein aggregation was not accompanied by gross protein denaturation, as monitored by differential scanning calorimetry. No evidence was found for a link between extent of lipid oxidation and degree of protein aggregation or water holding capacity changes.

Changes in water-holding capacity of halibut muscle during cold storage

A useful tool for describing quality in muscle foods post mortem is to measure the water-holding capacity (WHC) of muscle. Two storage experiments were carried out to study the changes of WHC in halibut muscle during chilled storage for 15 and 18 days, respectively. To investigate the effect of normal spoilage bacteria on WHC, the storage experiments were performed both in the presence and absence of bacteria. Bacterial growth was inhibited by soaking the muscle in 3 mM NaN 3 prior to storage . A centrifugal technique was used to measure WHC. Under normal conditions, the liquid loss (LL) initially increased followed by a decrease after approximately 8 days. When bacterial growth was inhibited, no such reduction in LL was observed before day 18. Under normal storage conditions, no increase in muscle pH due to bacterial growth that could explain the improved WHC, was detected. The expelled water was analysed in order to investigate the mechanisms behind the changing WHC during storage. In both experiments, the total amount of protein lost from the muscle tissue correlated to the amount of LL. Hydroxyproline could only be observed in the LL from muscle heated to 50°C and no significant changes were observed during storage. This indicates that extensive solubilisation of collagen did not occur during the storage period. Hexuronic acid was detected in the LL but no time-dependent increase could be observed. In the normal samples, the amount of hexuronic acid in the LL actually appeared to decrease in the last part of the storage period. Gelatinolytic activities in the muscle tissue during storage were investigated by gelatine zymography. The results showed that samples with spoilage bacteria present had higher gelatinolytic activities. The increased proteolytic activities are likely to result in more degradation of proteins including core protein of proteoglycans, which then contribute to the increased WHC.

Paper mill residuals and compost effects on soil carbon and physical properties.

Use of organic by-products as soil amendments in agricultural production exemplifies a strategy for converting wastes to resources. The overall objective of this research was to evaluate the short- and intermediate-term effects of repeatedly amending sandy soil with paper mill residuals (PMR) and composted PMR in a vegetable rotation in Wisconsin's Central Sands. Specifically, we investigated the effects of PMR and composted PMR on total soil C and related these to changes in water-holding capacity and plant-available water (PAW). Amendment effects on irrigation requirements were estimated with a simple soil water balance model. The experimental design was replicated five times as a randomized complete block with four organic amendments: raw PMR, PMR composted alone (PMRC), PMR composted with bark (PMRB), and peat applied at two rates and a non-amended control. All amended treatments significantly increased total soil C relative to the nonamended control following applications in 1998 and 1999. One year following the second serial amendment, all PMR treatments increased PAW by 5 to 45% relative to the control. There was a significant positive linear relationship between total soil C and PAW. All amended treatments reduced the average amount of irrigation water required for potato production by 4 to 30% and the number of irrigation events by 10 to 90%. There was a clear trend of greater reduction in irrigation requirements with more carbon added. The cumulative effects of repeated additions of PMRB suggest that certain composts might sustain elevated PAW and reduce irrigation requirements beyond one year.