Cassava pomace-based biodegradable packaging materials: a review.

Starch-based biodegradable packaging materials are gaining popularity as an alternative to the adverse environmental effects caused by conventional packaging materials. Despite the fact that cassava can withstand harsh environmental conditions and convert a greater quantity of solar energy into carbohydrates, its postharvest shelf life is extremely short. The preparation of cassava starch is an important method for extending the storage life of cassava. When one ton of cassava is processed, approximately 900 kg of cassava pomace, also known as cassava bagasse and cassava pulp, are produced. Due to the high residual starch and fibre content, reinforced packaging materials made from cassava pomace predominate. In the present manuscript, many possible uses of cassava pomace in packaging materials are discussed.  Furthermore, the performance attributes of packing materials assume a crucial role in the evaluation of the quality of the respective materials. The manuscript discusses various performance characteristics of packaging materials derived from cassava pomace. The features discussed include water vapour permeability, moisture content, solubility, thickness, colour, light barrier properties, mechanical properties, FT-IR analysis, thermal stability, biodegradation, contact angle, and the presence of plasticizers. Though cassava starch film has become a favourable substitute for conventional packaging materials, commercialization is limited due to having drawbacks, and the current solutions are also catalogued in this review.

Use of fenugreek seed gum in edible film formation: major drawbacks and applicable methods to overcome.

Researching on potential biopolymer sources with the aim of developing edible films with better mechanical and barrier properties has become innovative as it would be a key factor to minimize the use of synthetic polymers in food packaging. Therefore, different biopolymers such as galactomannan have been gaining attention recently. Fenugreek seed gum is a rich source of galactomannan which is minimally researched on its applicability in edible film making. The degree of galactose substitution and polymerization are the main factors that determine the functional properties of galactomannan. A strong and cohesive film matrix cannot be produced from fenugreek seed gum as its molecular interaction is weakened due to the high galactose substitution with a high galactose/mannose ratio, 1:1. Structural modifications of galactomannan in fenugreek seed gum will lead to films with the required mechanical properties. Hence, this review summarizes recent scientific studies on the limitations of fenugreek seed gum as a film forming agent and the specific modification techniques that can be applied in order to increase its film forming capability and performance.

Comparison of Different Hydrocolloids on the Novel Development of Muffins from "Purple Yam" (Dioscorea alata) Flour in Sensory, Textural, and Nutritional Aspects.

Hydrocolloids can act as gluten substitutes to form the structural equivalents of the gluten network in gluten-free bakery products. "Purple yam" (Dioscorea alata) is one of the underutilized yams in Sri Lanka with high nutritional potential. The overall objective of this study was to develop gluten-free muffins using "Purple yam" (Dioscorea alata) flour with hydrocolloids (pectin, xanthan gum, and guar gum) and investigate the nutritional composition and selected properties of the muffins. The texture profiles of gluten-free muffins were analyzed through the following parameters: hardness, adhesiveness, cohesiveness, etc. The chromameter values were obtained and sensory evaluations for gluten-free muffins were carried out. The highest moisture content was recorded in pectin-incorporated muffins (17.70 ± 0.50%). The protein content of all three types of muffins was around 5%. The highest fat content was recorded in pectin-incorporated muffins (19.26 ± 0.51%). The ash content of all three types of muffins was around 2%. Potassium was the most predominant element found in each muffin. The hardness of guar gum-incorporated muffin (6379.3 ± 135.9 g) was greater than that of the pectin-incorporated one (6082.3 ± 23.4 g). Xanthan gum-incorporated muffins had significantly decreased cohesiveness (0.19 ± 0.04). The highest springiness was obtained in pectin-incorporated muffin (37.13 ± 1.61 mm). The descending order of the chewiness of muffin is pectin - added > xanthan gum - added > guar gum - added sample. According to the sensory evaluation, pectin-incorporated muffin was the best as it had obtained the highest sum of ranks for appearance, color, taste, after taste, and overall acceptability.

Influence of Cooking Methods on Antioxidant Activities of Selected Leafy Vegetables Gymnema lactiferum, Wattakaka volubilis, and Argyreia populifolia in Sri Lanka.

Green leafy vegetables (GLVs) are abundant in bioactive compounds and constitute a crucial part of a balanced diet. Sri Lankan green leafy vegetables which are edible and available for consumption have not been thoroughly investigated, whilst their consumption can deflate the risk of arising several degenerative diseases, such as cancer and cardiovascular diseases. The present study was aimed at evaluating the antioxidant capacities of the leafy vegetables, Gymnema lactiferum (Kurignan), Wattakaka volubilis (Aguna), and Argyreia populifolia (Girithilla), with different thermal treatments (70°C, 120°C, and 170°C) which are used in domestic cooking processes. Heat treatments significantly affect the antioxidant capacity and polyphenolic content of most vegetables analyzed, either increasing or decreasing the concentration of these compounds. In the presence of thermal treatments, Gymnema lactiferum (14.52-20.28 mg GAE/g DW) and Wattakaka volubilis (19.75-27.13 mg GAE/g DW) showed a significantly higher (p < 0.05) total phenolic content. The temperature treatment did not alter the ABTS radical scavenging activity in Gymnema lactiferum. In contrast, an increment of ferric reducing antioxidant power (41.26-54.85 mg TE/g DW) and DPPH radical scavenging activity (0.11-0.26 mg TE/g DW) was observed. Wattakaka volubilis treated at 170°C appeared to have a significantly higher amount (104.93 ± 1.41 mg TE/g DW) of ferric reducing antioxidant power compared to its raw form. All cooking processes with their corresponding thermal treatments caused a significantly lower (p < 0) amount of antioxidant capacity in Argyreia populifolia.

Functional, Physicochemical, and Antioxidant Properties of Flour and Cookies from Two Different Banana Varieties (Musa acuminata cv. Pisang awak and Musa acuminata cv. Red dacca).

Banana (Musa acuminata) is grown abundantly in tropical and subtropical countries, and it is consumed as raw or processed. Banana is a significant source of nutrients, and it has been found to contain carbohydrates and other nutritional components. The present study was conducted to evaluate the proximate composition, antioxidant composition, and physicochemical properties of flour obtained from two different banana varieties (Musa acuminata cv. Pisang awak and Musa acuminata cv. Red dacca) and to evaluate the proximate composition and antioxidant composition of cookies prepared by incorporating both banana flours. Several sets of cookie samples were prepared separately by incorporating each banana flour where wheat flour and banana flour combinations were 85%-15%, 75%-25%, 70%-30%, and 0-100%. These samples were evaluated for sensory attributes, and two best cookie formulations were selected (70% wheat flour and 30% banana flour) for the analysis. Both Awak and Dacca had obtained similar amount of carbohydrates p < 0.05 while Dacca had recorded a higher amount of moisture, fat, protein, ash, and phytonutrients such as polyphenols, antioxidants, and flavonoids. Dacca flour had obtained higher values for physicochemical properties like water holding capacity (WHC) and oil holding capacity (OHC). L ∗, a ∗, and b ∗ values were evaluated for banana flour incorporated cookies. Lightness and the redness of cookies were prominent while yellowness was not prominent. There was no significant difference in texture parameters but hardness was higher in banana cookies as they contained a higher content of protein and fiber.

Preparation of liquid-core hydrogel beads using antioxidant-rich Syzygium caryophyllatum fruit pulp as a healthy snack.

Reverse spherification is a common technique used in molecular gastronomy to produce innovative products with an improved texture by shaping a liquid into an edible semisolid sphere that gives a burst in the mouth sensation. In this study, liquid-core hydrogel beads (LHBs) were prepared using Syzygium caryophyllatum fruit pulp adapting reverse-phase molecular gastronomy as a minimal processing technique to promote it as a healthy snack. Three types of hydrogel beads were formulated while considering the stability of LHBs. Long-term hardening of fruit juice in sodium alginate solution and the addition of plasticizer was used as two methods to increase the textural stability of LHBs. Results revealed that the addition of the plasticizer imparted to improve all the physical and textural properties of beads; however, it affects the transparency of the hydrogel membrane as well. Although the plasticizer increased the textural stability of LHBs, prolong inlaying them in it (the plasticizer) contribute to occur adverse consequences on the quality. Hence, the inlaying of LHBs in glycerol for 2 min was selected as the best treatment (HBP1). Since HBP1 had a low hardness (125.00 g) and high resilience (0.21), it imparted a chewing gum-like texture to LHBs. Hence, it (HBP1) can be used as a healthy snack. While HBP1 was capable of retained 90% antioxidant activity of fresh fruit of S. caryophyllatum, total polyphenolic content, 2,2-diphenyl-2-picryl-hydrazyl scavenging activity %, and ferric reducing antioxidant power value of this formulation were 59.50 GAE/g of dried LHBs, 68.96% and 139.69 TE/g of dried LHBs, respectively.

Effect of Steam Blanching, Dehydration Temperature & Time, on the Sensory and Nutritional Properties of a Herbal Tea Developed from Moringa oleifera Leaves.

The core purpose of the current study is to explore the use of Moringa oleifera leaves, to produce a herbal tea with acceptable sensory properties and nutritional properties by utilizing the steam blanching technique, different dehydration temperatures and time, which can be accepted in the Sri Lankan market. Six sets of samples were prepared where temperature and time combinations were 55°C-6 h, 60°C-4.30 h, 65°C-3 h for the unblanched samples & 55°C-6 h, 60°C-5.30 h & 65°C-4 h for the steam blanched samples. These samples were evaluated, employing a trained panel of 5 tea tasters and a semi trained panel of 35 members. The sample code 706 (steam blanched, 65°C-4 h) was selected as the sample with best sensory attributes. The blanched and unblanched samples dried at 65°C were tested for their proximate, mineral, vitamin, antioxidant and phytochemical contents. The effects of steam blanching on these two samples were evaluated & compared. This study highlights that steam blanching significantly increased the carbohydrates, fat, Mn, Fe, vitamin A, vitamin E and the DPPH scavenging activity whereas steam blanching significantly reduced the protein, fiber, Na, K, Ca, Total phenolic contents and flavonoids content but vitamin C, Zn, Cu and Mg contents were unaffected by steam blanching.