Bioactive Components and Anticancer Activities of Spray-Dried New Zealand Tamarillo Powder.

Tamarillo fruit contains many phytochemicals that have beneficial therapeutic and nutritional properties. Spray-drying is widely used to preserve fruit puree in powder form. However, to obtain high-quality fruit powder, the optimisation of spray-drying conditions is necessary, as a high drying temperature can damage sensitive bioactive compounds. This study investigated the effects of spray-drying on the microstructure, polyphenolics, total flavonoids, total carotenoids, antioxidant activity, and anticancer capacity of tamarillo powder. Response surface methodology (RSM) was used to optimise the spray-drying process to produce tamarillo powder. The independent variables were inlet drying temperature (120-160 °C), flow rate (1-5 g/mL), and maltodextrin concentration (0-10%). These variables influenced the microstructural attributes, bioactive components, and cytotoxicity of the spray-dried tamarillo powder. The increase in polyphenols and antioxidant activities were favoured under high-temperature spray drying conditions and a low carrier concentration. The optimised spray-drying conditions for producing tamarillo powder with high antioxidant and anticancer activities, high yield, and stable bioactive compounds were found to be at 146.8 °C inlet temperature, and a flow rate of 1.76 g/mL.

Pulsed Electric Field Pretreatments Affect the Metabolite Profile and Antioxidant Activities of Freeze- and Air-Dried New Zealand Apricots.

Pulsed electric field (PEF) pretreatment has been shown to improve the quality of dried fruits in terms of antioxidant activity and bioactive compounds. In this study, apricots were pretreated with PEF at different field strengths (0.7 kV/cm; 1.2 kV/cm and 1.8 kv/cm) at a frequency of 50 Hz, and electric pulses coming in every 20 µs for 30 s, prior to freeze-drying and air-drying treatments. PEF treatments were carried out at different field strengths. The impact of different pretreatments on the quality of dried apricot was determined in terms of physical properties, antioxidant activity, total phenolic content, and metabolite profile. PEF pretreatments significantly (p < 0.05) increased firmness of all the air-dried samples the most by 4-7-fold and most freeze-dried apricot samples (44.2% to 98.64%) compared to the control group. However, PEF treatment at 1.2 kV/cm did not have any effect on hardness of the freeze-dried sample. The moisture content and water activity of freeze-dried samples were found to be significantly lower than those of air-dried samples. Scanning electron microscopy results revealed that air drying caused the loss of fruit structure due to significant moisture loss, while freeze drying preserved the honeycomb structure of the apricot flesh, with increased pore sizes observed at higher PEF intensities. PEF pretreatment also significantly increased the antioxidant activity and total phenol content of both air-dried and freeze-dried apricots. PEF treatment also significantly (p < 0.05) increased amino acid and fatty acid content of air-dried samples but significantly (p < 0.05) decreased sugar content. Almost all amino acids (except tyrosine, alanine, and threonine) significantly increased with increasing PEF intensity. The results of this study suggest that PEF pretreatment can influence the quality of air-dried and freeze-dried apricots in terms antioxidant activity and metabolites such as amino acids, fatty acids, sugar, organic acids, and phenolic compounds. The most effective treatment for preserving the quality of dried apricots is freeze drying combined with high-intensity (1.8 kv/cm) PEF treatment.

Effects of Laccase and Transglutaminase on the Physicochemical and Functional Properties of Hybrid Lupin and Whey Protein Powder.

Plant-based protein is considered a sustainable protein source and has increased in demand recently. However, products containing plant-based proteins require further modification to achieve the desired functionalities akin to those present in animal protein products. This study aimed to investigate the effects of enzymes as cross-linking reagents on the physicochemical and functional properties of hybrid plant- and animal-based proteins in which lupin and whey proteins were chosen as representatives, respectively. They were hybridised through enzymatic cross-linking using two laccases (laccase R, derived from Rhus vernicifera and laccase T, derived from Trametes versicolor) and transglutaminase (TG). The cross-linking experiments were conducted by mixing aqueous solutions of lupin flour and whey protein concentrate powder in a ratio of 1:1 of protein content under the conditions of pH 7, 40 °C for 20 h and in the presence of laccase T, laccase R, or TG. The cross-linked mixtures were freeze-dried, and the powders obtained were assessed for their cross-linking pattern, colour, charge distribution (ζ-potential), particle size, thermal stability, morphology, solubility, foaming and emulsifying properties, and total amino acid content. The findings showed that cross-linking with laccase R significantly improved the protein solubility, emulsion stability and foaming ability of the mixture, whereas these functionalities were lower in the TG-treated mixture due to extensive cross-linking. Furthermore, the mixture treated with laccase T turned brownish in colour and showed a decrease in total amino acid content which could be due to the enzyme's oxidative cross-linking mechanism. Also, the occurrence of cross-linking in the lupin and whey mixture was indicated by changes in other investigated parameters such as particle size, ζ-potential, etc., as compared to the control samples. The obtained results suggested that enzymatic cross-linking, depending on the type of enzyme used, could impact the physicochemical and functional properties of hybrid plant- and animal-based proteins, potentially influencing their applications in food.

Identifying sensory attributes of Korean rice wine (makgeolli) using sensory evaluation and chemical analysis.

Makgeolli is a traditional alcoholic beverage in Korea; however, research on makgeolli is limited in foreign markets such as New Zealand. This study seeks to identify sensory descriptors that best describe makgeolli among New Zealand consumers. Four methods of making makgeolli have been identified based on different processing times and the number of fermentation stages. Chemical analysis and sensory evaluation were carried out to establish the different sensory and flavor properties of the four different makgeolli samples. Chemical analysis using SPME-GC-MS was employed to understand the volatile compounds present in the four makgeolli samples, while two sensory tests were carried out simultaneously using Check-All-That-Apply (CATA) and Just-About-Right (JAR). A total of 45 volatile compounds were identified using SPME-GC-MS, and examples of major volatiles include 2-methyl-1-propanol (alcoholic flavor), limonene (citrus-like flavor), and hexanal (green/grass-like flavor). One hundred and twenty-nine subjects (n = 68 females) completed the sensory evaluation and were analyzed for this study. Female subjects tend to rate overall acceptance of makgeolli higher than male subjects; both subjects preferred 1SF-YN with the highest mean hedonic score, and the least preferred makgeolli was 1SF-N. From CATA, attributes such as apple, apricot, peach, sweet taste, and bubbly texture were statistically significant when describing makgeolli. For JAR, a high proportion of subjects indicated that sourness was too much in three of the four makgeolli samples. PRACTICAL APPLICATION: Research on rice wine in Western markets such as New Zealand is limited, and this study gives insight into how New Zealand consumers perceive Korean rice wine (makgeolli). Sensory participants in this study indicated that makgeolli is too sour and lacks sufficient sweetness in the majority of the samples examined. When launching makgeolli to the New Zealand market, practitioners need to optimize sweetness and reduce sourness to increase overall liking. Sensory terms used by subjects describing makgeolli include cider, apple, and sour.

Characterisation of Korean rice wine (makgeolli) prepared by different processing methods.

Four methods of preparing makgeolli, a traditional Korean turbid rice wine, were reported in this study. The four processing routes include single-stage simultaneous saccharification and fermentation of glutinous rice with nuruk - a Korean starter culture (1SF-N), single-stage fermentation with nuruk and yeast (1SF-YN), two-stage fermentation (2SF) and three-stage fermentation (3SF). Chemical analysis was used to determine how the different processing routes could affect the rice wine's properties in terms of alcohol content, pH, colour, mineral content, proximate composition, antioxidant activity, total phenolic content, sugar, free amino acid, and organic acid profile. Sensory analysis using polarised projective mapping (PPM) and 62 participants found that sweetness is the most desirable attribute for makgeolli among New Zealand consumers with sourness and bitterness as less desirable. The 2SF makgeolli sample had the highest concentration of glucose (8.2 mg/mL) and maltose (107 mg/mL) and in the PPM experiment was the most preferred out of the four processing methods. The 1SF-N makgeolli sample had the highest alcohol (13% ABV), crude protein (4.9%), antioxidant activity, total phenolic (621 mg GAE/L) and free amino acids content, however, it was the least overall liked makgeolli sample. Overall, the novelty of this research includes formulating a traditional Korean turbid rice wine in a Western country environment and evaluating consumer perception of makgeolli beyond the normal clientele in South Korea. From these results it is suggested that the properties of makgeolli can be manipulated via processing to suit the brewer's sensory needs that best fits the consumer market.

Converting avocado seeds into a ready to eat snack and analysing for persin and amygdalin.

Avocado seeds account for 13% of the waste from industrial production of cold-pressed avocado oil (CPAO). Therefore, the aim of this study was to valorise avocado seeds by converting it into an extruded snack product using a friction cooker and comparing their textural and physical characteristics to extruded brown rice and malted barley ready to eat (RTE) snacks. Concentration of toxins; amygdalin and persin were compared in extruded avocado seed and fresh avocado seeds. Avocado seed extrudates were significantly lower in lateral expansion, apparent density, porosity, hardness, and crispiness compared to brown rice extrudates. Antioxidant capacity and total phenolic content (TPC) was highest in freeze-dried avocado seeds. Antioxidant capacity and TPC of avocado seed extrudates were significantly higher than brown rice and malted barley. The concentrations of both amygdalin and persin in the RTE avocado seed snack were present at non-toxic levels (2.6 × 10-6 mg/g and 0.68 mg/g respectively).

Metabolite profiling identifies chemical markers associated with the cytotoxic properties of roasted fermented avocado seeds.

Studies have demonstrated avocado seeds are a good source of bioactive compounds. This study investigated the effects of roasting on the metabolites and anticancer activities of fermented avocado seeds. All three anti-cancer activities of fermented avocado seeds were higher at lower roasting temperature and time. The best inhibition effect was found against Hep G2 followed by the MDA-MB-231 and MCF-7 cancer cell lines. Untargeted metabolite profiling using gas chromatography-mass spectrometry resulted in identification of 208 metabolites. In total, 41 metabolites identified had VIP values more than 1 using PLS-R that were related to anticancer activities. All amino acids and most sugars were higher at lower roasting temperature and positively correlated to anticancer activity. The roasting conditions for optimal antioxidant and anticancer activities were determined to be 121 °C for 9 min. Findings showed that fermented avocado seed powder has the potential to become a functional food ingredient with beneficial bioctive properties.

A comprehensive chemical analysis of New Zealand honeydew honey.

Demand for honeydew honey (HDH) is growing, both from consumers and the food industry, due to its potential antimicrobial, anti-inflammatory, and antioxidant properties. However, information on the chemical profile of HDH remains scant, particularly on New Zealand honeydew honey (NZHDH). This paper aims to provide a comprehensive chemical analysis of NZHDH produced from honeybees, which feed on nectar exuded by the scale insect Ultracoelostoma assimile. This insect feeds on most species of the Southern Beech (Nothofagus spp.). The proximate composition, mineral profile, sugar profile, phenolic profile, amino acid profile, and antioxidant activity of NZHDH was determined and compared to results for HDH and other varieties of honey previously reported in literature. It was determined that the antioxidant activity of NZHDH is comparable to several studies on Manuka honey, which is widely considered as the "gold standard" for its antioxidant activity. This demonstrated that NZHDH indeed had excellent antioxidant properties. This study was the first time that a quantitative amino acid profile has been produced for NZHDH. The major amino acids were proline, L-aspartic acid, L-glutamic acid, L-alaine, and L-phenylalanine. The major phenolic compounds were pinocembrin, abscisic acid, and pinobanksin. Of the phenolic compounds quantified in this study, only p-hydroxybenzoic acid has previously been quantified in NZHDH.

A Comprehensive Chemical and Nutritional Analysis of New Zealand Yacon Concentrate.

Global interest in yacon (Smallanthus sonchifolius) is growing due to its potential as a functional food, attributable to its unique profile of bioactives and high fructooligosaccharide (FOS) content, which vary between cultivars. Our objective was to conduct a comprehensive chemical and nutritional analysis of New Zealand yacon concentrate (NZYC)-a sweet syrup derived from the roots of cultivar 'New Zealand', which was first grown in the 1980s. The major minerals in NZYC were potassium, phosphorus, and calcium. The FOS content ranged from 17.6 to 52.7 g/100g. Total phenolic content ranged from 565 to 785 mg gallic acid equivalents per 100 g; chlorogenic acid and caffeic acid were the major phenolic compounds. The major amino acids were L-arginine, L-glutamic acid, L-proline, L-aspartic acid, and asparagine. The major organic acids were citric, malic, quinic, and fumaric acids. Antioxidant activity ranged from 1084.14 to 3085.78 mg Trolox equivalents per 100 g depending on the assay used. The glycaemic index (GI) value was 40 ± 0.22, classifying it as a low-GI food. These results support the classification of NZYC as a nutraceutical food product for future diet therapy applications.

Optimising the Spray Drying of Avocado Wastewater and Use of the Powder as a Food Preservative for Preventing Lipid Peroxidation.

Avocado wastewater (AWW) is the largest by-product of cold pressed avocado oil. The aim of this study was to valorise AWW by converting it into spray dried powder for use as a lipid peroxidation inhibiting food preservative. To increase the powder yield of AWW, addition of carriers and spray drying parameters (temperature and feed flow rate) were optimised. The highest AWW powder yield was 49%, and was obtained using 5% whey protein concentrate (WPC), with a feed flow rate of 5.8 g/min and an inlet drying temperature of 160 °C. The liquid chromatography mass spectrophotometry (LC-MS) analysis showed that AWW encapsulated with WPC had the highest retention of α-tocopherol (181.6 mg/kg powder). AWW with 5% WPC was tested as a preservative in pork fat cooked at 180 °C for 15 min. Thiobarbaturic acid reactive substances (TBARS) assay showed that the effectiveness of AWW powder was comparable to commercial additives such as butylated hydroxytoluene (BHT), butylated hydroxyanisole (BHA), and sodium erythorbate (E316).

Converting industrial organic waste from the cold-pressed avocado oil production line into a potential food preservative.

The production of commercial cold pressed avocado oil (CPAO) generates large quantity of organic wastes such as pomace, seeds, peels and wastewater. During the early harvest season, for every 1000 kg of avocado fruits processed, roughly 80 kg of oil is produced and wastewater accounted for the highest proportion (500 kg). Therefore, it is important to find an alternative application for this wastewater rather than its direct disposal into landfills. Proximate analysis, total phenolic content (TPC) and antioxidant assays were conducted on the avocado wastes. Avocado wastewater (AWW) was spray dried into powder at different temperatures from 110 °C to 160 °C, which concomitantly increased the TPC and antioxidant capacities of the AWW powder. The powder was further applied as a preservative in pork sausages and was found to be effective in preventing lipid oxidation.