Development and evaluation of a vacuum impregnation system for enhancement of biochemical properties of food materials.

Vacuum impregnation is a novel methodology for adding various substances to porous foods. This study aimed to develop a cost effective automate system for vacuum impregnation of food materials to enhance their nutritional, functional and sensory properties depending on the functionality of the impregnation solution. The developed vacuum impregnation system includes a vacuum chamber, vacuum pump and an automation setup for creating and maintaining vacuum conditions, feeding impregnated solutions to the samples and releasing vacuum. Fresh-cut spinach leaves were impregnated with ascorbic acid (AsA) and calcium chloride (Cacl2) (10% concentration) in the setup in order to test the effect of the process on some biochemical properties. Statistical analysis revealed significant effect of vacuum impregnation on the biochemical properties (total soluble solids, total phenolic content, flavonoid content and free radical scavenging activity) and color of spinach leaves during storage up to 4 days. Impregnation process showed significant increase in the total phenolic and flavonoid content of the spinach leaves. Increment up to 78% in antioxidant activity was seen for the uncoated impregnated leaves as compared to 59% activity in untreated samples. Thus, products with desired parameters can be produced with this process with minimal impact on their properties at a lower cost and in a shorter time period.

Optimization of process parameters of refractance window drying for aonla slices and comparison with other drying techniques.

BACKROUND: Aonla is as a good source of antioxidants due to its high ascorbic acid and polyphenol contents. However, because of its high acidity and astringent taste, aonla is rarely consumed in its fresh form. As the constituents in aonla are heat sensitive, it is essential to find a suitable drying method for preservation. Therefore, refractance window drying (RWD) of aonla slices was studied as it has the potential of retaining heat-sensitive compounds. RESULTS: The effect of RWD process variables, namely water temperature (75, 82.5, 90 °C) and slice thickness (2, 4, 6 mm), on different quality parameters of dehydrated aonla was studied. Increasing water temperature resulted in significantly higher ascorbic acid content, titratable acidity and product temperature, while total phenolic content, free radical scavenging activity and moisture content decreased. With the exception of product temperature, higher slice thickness led to an increase in the values of all the parameters. At the optimized processing conditions of 83 °C water temperature and 4 mm slice thickness, the ascorbic acid content, total phenolic content, free radical scavenging activity, titratable acidity and moisture content values were found to be 269.03 mg (100 g)-1, 242.33 mg (100 g)-1, 87.11%, 3.62% and 4% respectively. The aonla slices subjected to RWD also possessed 4-6% higher phytochemical content than osmotically dried and hot-air-dried samples. CONCLUSION: This research highlights the effectiveness of RWD in preserving heat-sensitive compounds in food like aonla. The RW-dried slices had a smoother and more uniform microstructure compared to osmotically dried and hot-air-dried samples. © 2024 Society of Chemical Industry.

Enhancing phytochemical parameters in broccoli through vacuum impregnation and their prediction with comparative ANN and RSM models.

Amidst increasing demand for nutritious foods, the quest for effective methods to enhance health-promoting attributes has intensified. Vacuum impregnation (VI) is a promising technique to augment produce properties while minimizing impacts on biochemical attributes. In light of broccoli's growing popularity driven by its nutritional benefits, this study explores the impact of VI using ascorbic acid and calcium chloride as impregnation agents on enhancing its phytochemical properties. Response surface methodology (RSM) was used for optimization of the vacuum impregnation process with Vacuum pressure (0.6, 0.4, 0.2 bar), vacuum time (3, 7, 11 min), restoration time (5, 10, 15 min), and concentrations (0.5, 1.0, 1.5%) as independent parameters. The influence of these process parameters on six targeted responses viz. total phenolic content (TPC), total flavonoid content (TFC), ascorbic acid content (AAC), total chlorophyll content (TCC), free radical scavenging activity (FRSA), and carotenoid content (CC) were analysed. Levenberg-Marquardt back propagated neural network (LMB-ANN) was used to model the impregnation process. Multiple response optimization of the vacuum impregnation process indicated an optimum condition of 0.2 bar vacuum pressure, 11 min of vacuum time, 12 min of restoration time, and 1.5% concentration of solution for vacuum impregnation of broccoli. The values of TPC, TFC, AAC, TCC, FRSA, and CC obtained at optimized conditions were 291.20 mg GAE/100 g, 11.29 mg QE/100 g, 350.81 mg/100 g, 1.21 mg/100 g, 79.77 mg, and 8.51 mg, respectively. The prediction models obtained through ANN was found suitable for predicting the responses with less standard errors and higher R2 value as compared to RSM models. Instrumental characterization (FTIR, XRD and SEM analysis) of untreated and treated samples were done to see the effect of impregnation on microstructural and morphological changes in broccoli. The results showed enhancement in the TPC, TFC, AAC, TCC, FRSA, and CC values of broccoli florets with impregnation. The FTIR and XRD analysis also supported the results.

Gaseous ozone treatment of chickpea grains: Effect on functional groups, thermal behavior, pasting properties, morphological features, and phytochemicals.

The applicability of ozone has been increased to include pulse grains because of their increased production and significance as plant-based protein source. In many developed countries, there is a growing demand for products made from chickpeas grains. Whole chickpea grains were treated with ozone gas (500-1000 ppm) for 20-30 min. The structural, thermal, pasting properties, and phytochemicals of the ozone-treated, as well as control samples, were evaluated. Minor structural changes in the functional groups in the protein and starch molecules were observed in the treated sample. Ozonation caused significant changes in the pasting properties such as peak viscosity, trough viscosity, breakdown viscosity, final viscosity, setback viscosity, and peak temperature values. Microstructure revealed a reduction in the particle sizes of chickpea powders with the severity of ozone treatment. The total flavonoids (41.35-48.94 mg QE), alkaloids (1120.24-1453.57µg/g), and xanthoprotein (0.995-1.387 µg/g) increased significantly (p < 0.05) with ozone treatment. Commercially, chickpea grains can be ozone treated for achieving desired functional characteristics in a target product. PRACTICAL APPLICATION: Before consuming grain that has been treated with gaseous ozone, it is vitally important for all consumers to have a solid understanding of the facts presented here regarding variations in the chickpea nutritional profile. The impact of ozone treatment on functional groups, thermal behavior, pasting properties, and morphological features in chickpeas reveals vital information regarding changes occurred on macromolecules such as starch, proteins, and bioactive compounds. Since ozonation aids in extraction of health-beneficial bioactive compounds and brings about change in the starch and protein morphology, making them more digestible, it can be highly useful in preparation of health foods.

Gaseous ozone treatment of chickpea grains, part I: Effect on protein, amino acid, fatty acid, mineral content, and microstructure.

The effect of gaseous ozone (500-1000 ppm) treatment on the protein, amino acid, and fatty acid profiles, mineral content, and the microstructure of the chickpea grains were evaluated. Though protein content was not altered significantly, SDS PAGE profiling exhibited minor modifications in the protein bands of the treated chickpea. The essential amino acids (EAA) and total amino acids (TAA) slightly decreased, ratio of EAA to TAA increased, while the calculated protein efficiency ratio decreased. Significant decrease in the SH content and non-significant increase in SS content was observed at higher doses of ozone. The overall saturated and unsaturated fatty acids (%) were in the range of 13.05-13.49 and 86.51-87.61, respectively. The minerals were stable and the HCl extractability decreased in the ozonated samples. There was some minor degradation of intracellular cell wall and distribution of starch and protein bodies in the ozonated sample.

Mass transfer dynamics of simultaneous water gain and solid loss during soaking of pigeon pea grains.

Pigeon pea is the most prominently used protein source for human consumption. This is one of the leading pulse utilized in various applications in food processing. Soaking is one of the mandatory unit operation required to convert it from raw to a consumable form. Insights into its mass transfer dynamics enable the design and optimization of processing conditions with due consideration of retention of its quality and nutrition. In the present investigation, the mass transfer dynamics of simultaneous water gain and solid loss taking place during soaking was studied . The experimental samples were soaked at 35, 50, 75, 85, and 100 °C to represent the lower and upper gelatinization temperatures. The water diffusivities varied from 5.492 × 10-10 to 13.84 × 10-10 m²/s when soaking temperature was increased from 35 to 100 °C. Similarly, solid diffusivities vary between 6.27 × 10-10 at 35 °C and 9.48 × 10-10 m²/s at 100 °C. The activation energies of both the phenomenon were estimated using the Arrhenius equation. The mass transfer process has been identified with three distinct stages. The first stage was characterized by void filling, expansion, and solid hydration. The second stage was marked at 5% of solid loss and characterized by solid loss, while the third stage contributed to the starch gelatinization process. Simultaneous water gain and solid loss in the grain was observed throughout the process at varying rates. The insights into mass transfers from this study can help in further modeling of pigeon pea soaking behavior. PRACTICAL APPLICATION: Soaking is one of the mandatory step for further utilization of legume grains. Various desirable and undesirable changes take place during the soaking process. Pigeon pea being a leading legume, understanding of the dynamics of various chemical, physical, and compositional changes during soaking is very much required for a process design. Also the representation of these behaviors in mathematical models is essential to further understand and optimize the operations for maximum retention of quality attributes, minimum wastage, and low-energy consumption.

Effect of composition and storage time on some physico-chemical and rheological properties of probiotic soy-cheese spread.

Probiotic soy-cheese spread was prepared by fermenting soymilk with specific probiotic starter culture, and there after processing the coagulated mass. Soy cheese spread samples had more than 109 cfu/g of viable probiotic count at the time of preparation; and had around 17.6% protein, 25.3% fat and 19.8% total soluble sugar. Compared to commercially available dairy cheese spread, probiotic soy cheese spread had significantly higher protein and anti-oxidant activity. Soy cheese spreads, prepared from pure soymilk as well as by mixing with dairy milk, were studied with respect to the differences in their rheological behavior during storage at refrigerated conditions. A dynamic oscillatory test was used to measure the viscoelastic properties of spreads at 0, 7, 14, 21 and 28 days of storage. It was observed that the storage modulus (G') was higher than the loss modulus (G″) throughout the storage period indicating that the soy cheese spreads exhibit predominantly elastic behavior. The cheese spread sample prepared by adding okara in soymilk had the highest values of G' and complex viscosity (1120 Pa and 11.5 Pa s, respectively at an angular frequency of 100 s-1). G', G″ and viscosity of cheese spread did not change significantly up to 14 days, with values of 650, 225 Pa and 7.43 Pa s, respectively for the sample prepared from soymilk alone. However, these values increased thereafter which might be an indication of structural changes in the cheese spread samples.

Jejunal perforation due to ingested buffalo bone mimicking acute appendicitis.

BACKGROUND: Foreign body ingestion is seen quite frequently in clinical practice, intestinal perforation due to this is rare. The foreign body often mimics another cause of acute abdomen and requires an emergency surgical intervention. The majority of patients do not recall ingesting sharp foreign bodies. CASE PRESENTATION: We report an interesting case of a fifty five year-old man who presented with pain in the right iliac fossa with localised tenderness which was clinically diagnosed as acute appendicitis. During the operation, the presence of purulent collection and the inflamed bowel with flakes raised suspicion of bowel perforation. The assessment of the proximal small bowel revealed two small perforations in the jejunum. A hard, bony and sharp object was extracted and the perforations were closed. Post-operative recovery was uneventful. Detailed food history was taken following the recovery of the patient from surgery. It revealed the history ingestion of home prepared buffalo meat. The extracted object was identified as 'buffalo bone' by the patient and the care taker of the patient. The jejunum was perforated by the ingested buffalo bone causing local peritonitis in right iliac fossa. CONCLUSION: Intestinal perforation by ingested foreign bodies should be suspected in acute abdomen. It requires a high degree of suspicion and awareness on the part of the clinician.