Search

Further investigations of almond degradation under typical industrial storage conditions from a quantitative perspective are warranted. This study modeled effects of packaging, temperature (TEMP), relative humidity (RH) and roasting on chemical attributes of almonds stored according to common industry practices throughout 16 months. Roasted samples were stored in high‐barrier bags (HBB) or polypropylene bags (PPB) at multiple combinations of TEMP and RH. Raw samples were held in unlined cardboard cartons (UC) or PPB under the same conditions. Almonds were assessed bimonthly for oxidation products, free fatty acids, moisture content and water activity. Results indicated roasting almonds improved quality preservation. Models showed HBB (rather than PPB) to provide benefits to stability comparable to reductions in storage TEMP of ~15 to 30 °C. PPB (rather than UC) showed benefits to peroxide formation of similar magnitude. Our data shows HBB to be a superior packaging choice, and UC to associate with the greatest rates of degradation.

Raw almonds are a major commodity, yet much is unknown about how storage conditions determine their shelf life. The storage stability, as measured by consumer assessments and chemical measures, of raw almonds was determined for samples stored in cardboard boxes and polypropylene packaging for 2 years at 4, 15, 25, and 35 °C, and at 50% and 65% relative humidity (RH). Samples stored in unlined cartons always failed (>25% rejection) before their counterparts stored in polypropylene bags under identical environmental conditions. Models determined that polypropylene packaging (as opposed to unlined cardboard cartons) extended the time until sample rejection by more than 7 months. Temperature and RH were both negatively associated with storage time until failure. Flavor was a greater contributor to consumer acceptability than texture or odor, while peroxide values and free fatty acids were of greater importance in predicting raw almond consumer quality than measures of conjugated dienes or 2‐thiobarbituric acid‐reactive substances. The results of this study will allow almond producers to determine packaging types and environmental storage conditions that provide shelf life of a specified time.

BACKGROUND Almonds contain considerable amounts of potential prebiotic components, and the roasting process may alter these components. The aim of this study was to compare the in vitro fermentation properties and in vivo prebiotic effect of raw and roasted almonds. RESULTS In vitro, predigested raw and roasted almonds promoted the growth of Lactobacillus acidophilus (La‐14) and Bifidobacterium breve (JCM 1192), and no significant differences were found between these two nuts. In a 4‐week animal trial, daily intake of raw or roasted almonds promoted the population of Bifidobacterium spp. and Lactobacillus spp. and inhibited the growth of Enterococcus spp. in faeces and caecal contains of rats. Compared with roasted almonds, raw almonds had a greater bifidobacteria promotion effect. Besides, significantly higher β‐galactosidase activity and lower β‐glucuronidase and azoreductase activities in faeces or caecal contents of rats were observed with raw almonds than with roasted almonds. While, in terms of metabolic effects, the ingestion of roasted almonds resulted in significantly greater intestinal lipase activities. CONCLUSION Both raw and roasted almonds exhibit potential prebiotic effects, including regulation of intestinal bacteria and improved metabolic activities. The roasting process may slightly reduce the prebiotic effects of almonds but significantly improve the metabolic effects.© 2016 The Authors. Journal of the Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.

UNLABELLED The objectives of this study were to measure sensory texture attributes of 5 types of almonds (blanched slivered, natural sliced, whole blanched, whole dry roasted, and natural whole) conditioned at 4 different moisture levels, to measure liking of a subset of these products, and to compare the sensory texture measurements with consumer liking ratings. Thirteen panelists trained to evaluate almond texture rated the texture attributes of the 20 almond samples. A panel of 113 almond consumers rated their liking of a subset of 8 of these almonds. Compared with the whole almonds, sliced and slivered almonds had less hardness, less crunchiness, less cohesiveness, less tooth packing, and required fewer chews and swallows to consume. Compared with slivered almonds, sliced almonds were more powdery, had more surface roughness, more loose particles, and were crisper. Compared with slivered almonds, sliced almonds were less hard, broke into fewer pieces, had less moistness and cohesiveness of mass, less fatty film, and required fewer chews and fewer swallows to consume. Dry roasted almonds were generally harder, more crisp, more crunchy, and produced more loose particles than natural almonds, which were, in turn, more hard, crisp, and crunchy than blanched almonds. As moisture content increased, moistness of mass and cohesiveness of mass increased. Crispness, number of pieces, hardness, crunchiness, persistence of crunch, and particulate mass decreased with increasing moisture content. Consumer texture liking ratings were highly positively correlated with the attributes crispness, crunchiness, and persistence of crunch. PRACTICAL APPLICATION In addition to roasting and blanching, water content of almonds is important for key texture properties. Almond producers can use this information to provide customers with almonds having texture properties important to consumers.

In-shell or shelled almonds inoculated with Salmonella were sprayed with water, acetic acid, citric acid, acidified sodium chlorite, peroxyacetic acid, or a mixture of citric, hydrochloric, and phosphoric acids before testing for Salmonella on xylose-lysine-deoxycholate (XLD) agar and tryptic soy agar (TSA). Spraying acids on in-shell almonds reduced about 0.48 to 1.88 and 0.22 to 0.67 log colony-forming units (CFU)/g of Salmonella on XLD agar and TSA counts, respectively, on the in-shell almonds but had no effect on the edible portion of the almonds (shelled almonds). When spraying acids on shelled almonds, a single spray application (1.6 mL acid solution/25 g of shelled almonds) with 1 min holding caused 0.72 to 1.93 and 0.38 to 1.35 log CFU/ g reductions of Salmonella counts on XLD agar and TSA, respectively. Increasing the holding time to 5 min did not enhance the reductions. When spraying shelled almonds, increasing the number of application (1 to 3 times) enhanced Salmonella reduction. Except for the peroxyacetic acids, increasing total holding time (5 to 120 min) improved the efficacies. Furthermore, increasing acid concentrations improved the efficacies of acetic, citric, and peroxyacetic acid treatments. Estimated 5-log reductions on both TSA and XLD counts can be achieved under laboratory conditions using 10% citric acid by (1) the combination of shelling, 1 spraying, and 3 d of storage, (2) the combination of shelling, 2 sprayings, and 1 d of storage, or (3) the combination of shelling and 3 sprayings. Acidic sprays may be utilized for enhancing the microbiological safety of raw nuts.

Nanostructuring of magnetically hard and soft materials is fascinating for exploring next-generation ultrastrong permanent magnets with less expensive rare-earth elements. However, the resulting hard/soft nanocomposites often exhibit random crystallographic orientations and monomorphological equiaxed grains, leading to inferior magnetic performances compared to corresponding pure rare-earth magnets. This study describes the first fabrication of a novel bimorphological anisotropic bulk nanocomposite using a multistep deformation approach, which consists of oriented hard-phase SmCo rod-shaped grains and soft-phase Fe(Co) equiaxed grains with a high fraction (≈28 wt%) and small size (≈10 nm). The nanocomposite exhibits a record-high energy product (28 MGOe) for this class of bulk materials with less rare-earth elements and outperforms, for the first time, the corresponding pure rare-earth magnet with 58% enhancement in energy product. These findings open up the door to moving from a pure permanent-magnet system to a stronger nanocomposite system at lower costs.