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Non-enzymatic browning develops in dry-cooked foods and those with high carbohydrate develop acrylamide, a neurotoxin and potential carcinogen. However, some non-enzymatic browning products have reducing properties. We hypothesized that non-enzymatic browning and reducing power, a measure of antioxidant activity, of processed yam are affected by pre-treatment. Peeled yam cultivars (KM, RKD and SO89) in chunks were pre-soaked (0, 3, 6, 12, 18, and 24 h) in distilled water or pre-blanched (0, 1, 2, 3, 4, and 5 min) in steam. Pre-treated samples were deep-fried at 180 °C for 15 min or roasted at 220 °C for 30 min. Soluble solids, titratable acidity and pH of yam tissues and soaking water were determined. pH of the soaked yam tissues showed a positive relation with non-enzymatic browning. Pre-soaked fried KM and roasted RKD showed a significant decrease in non-enzymatic browning intensities. The reducing power of the cooked yams ranged between 78.94 and 185.92 % of ascorbic acid, and was affected by the different pre-treatment and dry-cooking methods., Highlights • Soaking effectively in decreased non-enzymatic browning in both fried and roasted products of yam varieties. • Blanching affected non-enzymatic browning in the processed yam tissues differently for the different varieties. • pH, titratable acidity and soluble solids are important in non-enzymatic browning of soaked yam tissues. • Pre-treated yams have high reducing power as antioxidant activity. • Reducing power of processed yam is dependent on the variety and the processing method., Yams; blanching; soaking; non-enzymatic browning; reducing power.

Different proportions of orange‐fleshed sweet potatoes (OFSP) were used to substitute cassava mash and fermented spontaneously to produce composite gari—a gritty‐crispy ready‐to‐eat food product. Both the amount of OFSP and the fermentation duration (FD) caused significant increases in the β‐carotene content of the composite gari. OFSP addition reduced the luminance while roasting made the composite gari yellower when compared with the cake used. Addition of OFSP negatively affected the swelling capacity of the gari although not significant. The taste, texture, flavor, and the overall preferences for the composite gari decreased due to the addition of the OFSP but FD improved them. The sample with 10% OFSP and FD of 1.81 days was found to produce the optimal gari. One portion of the optimal gari would contribute to 34.75, 23.2, 23.2, 27, 17, and 16% of vitamin A requirements among children, adolescent, adult males, adult females, pregnant women, and lactating mothers, respectively. The study demonstrated that partial substitution of cassava with OFSP for gari production would have the potential to fight the high prevalence rate of vitamin A deficiency among less developed regions of Africa. PRACTICAL APPLICATIONS: Gari is a major staple for Ghanaians and people in the West African subregion due to its affordability and swelling capacity. It is mainly eaten raw with water, sugar, groundnut, and milk as gari‐soakings or with hot water to prepare gelatinized food called gari‐kai in Ghana or “eba” among Nigerians. However, gari is limited in β‐carotene, a precursor of vitamin A. Orange‐fleshed sweet potato (OFSP) is known to contain a large amount of β‐carotene, a vitamin A precursor. There is severe clinical vitamin A deficiency (VAD) prevalence among Ghanaians and many African countries. Therefore, addition of OFSP to gari would have the potential to fight the high prevalence rate of VAD among less developed regions of Africa.

Puroindoline (PIN) proteins are the molecular basis for wheat kernel texture classification and affect flour milling performance. This study investigated the effect of PINs on empirical rheology and pasting properties in Triticum turgidum ssp. durum and Triticum aestivum . Soft wheat (cv. Alpowa), durum wheat (cv. Svevo) and their derivatives in which PINs were deleted (Hard Alpowa) or expressed (cv. Soft Svevo). Presence of PINs affected flour particle size and damaged starch. PINs increased the pasting temperature and breakdown viscosity, while the effect on peak viscosity and setback were not consistent. Presence of PINs was negatively associated with GlutoPeak gluten aggregation energy and farinograph dough stability, suggesting a weakening of the gluten matrix. As regards dough extensibility, the role of PINs was evident only in common wheat: 5DS distal end deletion increased the resistance to extension, without affecting the dough extensibility. This study showed PINs to have different impact on pasting and rheological properties of T. aestivum and T. turgidum ssp. durum flours.

The effects of temperature (≥25°C) on dough rheological properties and gluten functionality have been investigated for decades, but no study has addressed the effect of low temperature (

The effect of puroindolines (PINs) on structural characteristics of wheat proteins was investigated in Triticum turgidum ssp. durum (cv. Svevo) and Triticum aestivum (cv. Alpowa) and in their respective derivatives in which PIN genes were expressed (Soft Svevo) or the distal end of the short arm of chromosome 5D was deleted and PINs were not expressed (Hard Alpowa). The presence of PINs decreased the amount of cold-SDS extractable proteins and the accessibility of protein thiols to specific reagents, but resulted in facilitated solvation of gluten proteins, as detected by tryptophan fluorescence measurements carried out on minimally mixed flour/water mixtures. We propose that PINs and gluten proteins are interacting in the grain or flour prior to mixing. Hydrophobic interactions between PINs and some of the gluten proteins modify the pattern of interactions among gluten proteins, thus providing an additional mechanistic rationale for the effects of PINs on kernel hardness.

Aims: The aim of the study was to assess the effect of gamma irradiation dose on quality attributes of minimally processed pineapple. Study Design: Physico-chemical quality parameters such as Total Soluble Solids (TSS), Titratable Acidity (TA), pH, Total Sugars (TS), Reducing Sugars (RS), Vitamin C, as well as Sensory and microbial quality of irradiated cut pineapples were studied over a period of 12 days at 5oC. Place and Duration of Study: This study was carried out at the Radiation Technology Center of Biotechnology and Nuclear Agriculture Research Institute, between May and Original Research Article

The effects of gamma irradiation on chitosan samples were determined in terms of physicochemical and functional properties. Shrimp chitosan was extracted from shell using a chemical process involving demineralization, deproteinization, decolorization and deacetylation. Commercial snow chitosan was also used. Samples (in a solid state) were given irradiation dose of 25 kGy at a dose rate of 1.1013 kGy/h in air and 0 kGy samples were used as controls. Results showed that moisture contents were between 8.690% and 13.645%. There were no significant differences (P>0.05) in the degree of deacetylation of the chitosan samples. Significant differences (P

The current study analyses consumer judgements about some existing as well as newly introduced brands of a processed cassava food product (fufu flour) by means of market testing. Except for colour, the respondents' evaluation of the sensory attributes of the various fufu flours that they have consumed did not have much significant differences. Also, no significant differences in sensory attributes were identified when the fufu flour brands were compared with traditional fufu, except for hand-feel, smoothness and elasticity. In addition, no significant differences were observed in the prices of the various fufu flour brands in comparison with the equivalent price of traditional fufu. The study finds diversification of the marketing outlet for fufu flour as a major factor that could contribute to improving the awareness of the product.

Acrylamide has been discovered in foods, especially high carbohydrate foods that are dry-cooked (baked, fried or roasted) at high temperatures which also create the conditions for non-enzymatic browning. Baking, frying and roasting are common food preparation methods in Ghana. Fifteen different high carbohydrate foods in Ghana, that undergo dry-cooking, have been investigated for non-enzymatic browning and acrylamide production. The products that showed notable non-enzymatic browning and acrylamide levels include fried sweet potato, plantain chips from the fresh produce, with their respective non-enzymatic browning and acrylamide values as 0.095 ± 0.006 optical density (OD), 1043 ± 47.6 parts per billion (ppb); 0.034 ± 0.03 OD, 568 ± 22.9 ppb. Roots and tuber products had relatively high non-enzymatic browning and acrylamide levels while plantain products showed low levels of non-enzymatic browning and acrylamide.